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Sample records for chorus giganteus gastropoda

  1. Marching Choruses

    DEFF Research Database (Denmark)

    Lech, Marcel Lysgaard

    2009-01-01

      This article re-examines the evidence for choral marching in the Athenian theatre, which has fostered ideas on the dramatic choruses as military training for young men, ephebes. But the late lexicographical sources are not relating to the dramatic choruses of the fifth-century and are in consta...

  2. Chorus in Agamemnon

    Institute of Scientific and Technical Information of China (English)

    叶宬

    2012-01-01

      Agamemnon is the first play in Orestea trilogy. It deals with the murder of Agamemnon by his wife Clytemnestra. As is known to al , chorus plays a very important role in Greek tragedy. The chorus is, for sure, consistent pretty much across the play of Agamemnon. It keeps accompany of Agamemnon, analyzing his behavior, criticizing his wrong deed. The intensity that chorus produces creates ups and downs of the plot. It is an inseparable part of the play.

  3. The Function of the Tragic Greek Chorus.

    Science.gov (United States)

    Weiner, Albert

    1980-01-01

    Discusses the function of the chorus in Greek tragedy and highlights interpretations of Aristotle's statements on the chorus. Concludes that the chorus' role was that of alienating the audience and was basically theatrical, not dramatic. (JMF)

  4. CHORUS : Fotografare l'invisible

    CERN Multimedia

    Jean Leyder

    1996-01-01

    5 maggio 1994, siamo al Centro Europeo per la Fisica delle particelle elementare, al CERN di Ginevra, ultime registrazioni su CHORUS, un microscope gigante per vedere delle particelle infinitamente piccole, delle particelle che si muovono alla velocita della luce ...

  5. New results of investigations of whistler-mode chorus emissions

    Directory of Open Access Journals (Sweden)

    O. Santolík

    2008-07-01

    Full Text Available This review summarizes selected recent results obtained during investigation of whistler-mode chorus emissions in the Earth's magnetosphere. Special attention is paid to results published during the last five years, with a focus on the results of the CLUSTER project. The nonlinear nature of chorus emissions is demonstrated using both theoretical results and measurements. Selected areas of research on whistler-mode chorus are covered and the paper especially reports new results on substructure and amplitudes of chorus wave packets, on new observations of frequency differences of chorus wave packets at different points in space and on their possible interpretations, on results concerning determination of position and size of the source region of chorus, on recent observational and theoretical results which lead to improved description of propagation of chorus from its source, and, finally, on comparison of chorus measurements with corresponding values deduced from nonlinear theory and simulations.

  6. Ducted propagation of chorus waves: Cluster observations

    Directory of Open Access Journals (Sweden)

    K. H. Yearby

    2011-09-01

    Full Text Available Ducted propagation of whistler waves in the terrestrial magnetosphere-ionosphere system was discussed and studied long before the first in-situ spacecraft measurements. While a number of implicit examples of the existence of ducted propagation have been found, direct observation of ducts has been hampered by the low sampling rates of measurements of the plasma density. The present paper is based on Cluster observations of chorus waves. The ability to use measurements of the spacecraft potential as a proxy for high time resolution electron density measurements is exploited to identify a number of cases when increased chorus wave power, observed within the radiation belts, is observed simultaneously with density enchantments. It is argued that the observation of ducted propagation of chorus implies modification of numerical models for plasma-wave interactions within the radiation belts.

  7. The trigger system of the CHORUS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Beuzekom, M.G. van [NIKHEF, Amsterdam (Netherlands); Boes, J.C. [NIKHEF, Amsterdam (Netherlands); Born, E.A. van den [NIKHEF, Amsterdam (Netherlands); Jaspers, M.J.F. [NIKHEF, Amsterdam (Netherlands); Konijn, J. [NIKHEF, Amsterdam (Netherlands); Oldeman, R.G.C. [NIKHEF, Amsterdam (Netherlands); Poel, C.A.F.J. van der [NIKHEF, Amsterdam (Netherlands); Reen, T. van [NIKHEF, Amsterdam (Netherlands); Stolte, J. [NIKHEF, Amsterdam (Netherlands); Uiterwijk, J.W.E. [NIKHEF, Amsterdam (Netherlands); Visschers, J.L. [NIKHEF, Amsterdam (Netherlands); Pesen, E. [Middle East Technical University, Ankara (Turkey); Zeyrek, M.T. [Middle East Technical University, Ankara (Turkey); Dewulf, J.P. [Inter-University Institute for High Energies (ULB-VUB), Brussels (Belgium); Bal, F. [CERN, EP Division, 1211 Geneva 23 (Switzerland); Beyer, R. [CERN, EP Division, 1211 Geneva 23 (Switzerland); Gorbunov, P. [CERN, EP Division, 1211 Geneva 23 (Switzerland); Ferreira, R. [CERN, EP Division, 1211 Geneva 23 (Switzerland); Friend, B. [CERN, EP Division, 1211 Geneva 23 (Switzerland); Jong, M. de [CERN, EP Division, 1211 Geneva 23 (Switzerland); Ludovici, L. [CERN, EP Division, 1211 Geneva 23 (Switzerland); Panman, J. [CERN, EP Division, 1211 Geneva 23 (Switzerland); Bonnet, L. [Universite Catholique de Louvain, Louvain-la-Neuve (Belgium); Gregoire, G. [Universite Catholique de Louvain, Louvain-la-Neuve (Belgium)

    1999-05-01

    A new apparatus for detection of {nu}{sub {mu}}{yields}{nu}{sub {tau}} oscillation has been successfully constructed and operated by the CHORUS Collaboration for the CERN-WA95 experiment. The design, implementation and performance of the electronic trigger system is described. A trigger efficiency of 99% was measured for {nu}{sub {mu}} charged-current events and 90% for neutral-current events.

  8. Breeding chorus indices are weakly related to estimated abundance of boreal chorus frogs

    Science.gov (United States)

    Corn, P.S.; Muths, E.; Kissel, A.M.; Scherer, R. D.

    2011-01-01

    Call surveys used to monitor breeding choruses of anuran amphibians generate index values that are frequently used to represent the number of male frogs present, but few studies have quantified this relationship. We compared abundance of male Boreal Chorus Frogs (Pseudacris maculata), estimated using capture–recapture methods in two populations in Colorado, to call index values derived from automated recordings. Single index values, such as might result from large monitoring efforts, were unrelated to population size. A synthetic call saturation index (CSI), the daily proportion of the maximum possible sum of index values derived from multiple recordings, was greater in larger populations, but the relationship was not highly predictive.

  9. A generation mechanism for chorus emission

    Directory of Open Access Journals (Sweden)

    V. Y. Trakhtengerts

    Full Text Available A chorus generation mechanism is discussed, which is based on interrelation of ELF/VLF noise-like and discrete emissions under the cyclotron wave-particle interactions. A natural ELF/VLF noise radiation is excited by the cyclotron instability mechanism in ducts with enhanced cold plasma density or at the plasmapause. This process is accompanied by a step-like deformation of the energetic electron distribution function in the velocity space, which is situated at the boundary between resonant and nonresonant particles. The step leads to the strong phase correlation of interacting particles and waves and to a new backward wave oscillator (BWO regime of wave generation, when an absolute cyclotron instability arises at the central cross section of the geomagnetic trap, in the form of a succession of discrete signals with growing frequency inside each element. The dynamical spectrum of a separate element is formed similar to triggered ELF/VLF emission, when the strong wavelet starts from the equatorial plane. The comparison is given of the model developed using some satellite and ground-based data. In particular, the appearance of separate groups of chorus signals with a duration 2-10 s can be connected with the preliminary stage of the step formation. BWO regime gives a succession period smaller than the bounce period of energetic electrons between the magnetic mirrors and can explain the observed intervals between chorus elements.

    Key words. Magnetospheric physics (Energetic particles · trapped. Space plasma physics (wave-particle interactions; waves and instabilities

  10. Animal choruses emerge from receiver psychology

    Science.gov (United States)

    Greenfield, Michael D.; Esquer-Garrigos, Yareli; Streiff, Réjane; Party, Virginie

    2016-01-01

    Synchrony and alternation in large animal choruses are often viewed as adaptations by which cooperating males increase their attractiveness to females or evade predators. Alternatively, these seemingly composed productions may simply emerge by default from the receiver psychology of mate choice. This second, emergent property hypothesis has been inferred from findings that females in various acoustic species ignore male calls that follow a neighbor’s by a brief interval, that males often adjust the timing of their call rhythm and reduce the incidence of ineffective, following calls, and from simulations modeling the collective outcome of male adjustments. However, the purported connection between male song timing and female preference has never been tested experimentally, and the emergent property hypothesis has remained speculative. Studying a distinctive katydid species genetically structured as isolated populations, we conducted a comparative phylogenetic analysis of the correlation between male call timing and female preference. We report that across 17 sampled populations male adjustments match the interval over which females prefer leading calls; moreover, this correlation holds after correction for phylogenetic signal. Our study is the first demonstration that male adjustments coevolved with female preferences and thereby confirms the critical link in the emergent property model of chorus evolution. PMID:27670673

  11. A generation mechanism of chorus emissions using BWO theory

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Ashutosh K; Singh, K K; Singh, A K; Patel, R P [Department of Physics, M. M. H. P. G. College, Ghaziabad (India); Singh, R, E-mail: abhay_s@rediffmail.co [Indian Institute of Geomagnetism, Navi Mumbai (India)

    2010-02-01

    In this paper, discrete VLF chorus emissions recorded at low latitude ground station Jammu (geomag. Lat. = 22{sup 0} 26{sup /} N, L = 1.17) are reported and their characteristics based on complete spectral analysis have been carried out. These discrete chorus emissions are generated during a strong geomagnetic storm period of 2-7 May, 1998. We have computed the sweep rate, repetition period, source region, and drift rate of the individual chorus elements. It is observed that the sweep rate increases with time. To explain the various temporal and spectral features of these emissions, a possible generation mechanism has been presented based on the backward wave oscillator (BWO) regime in the magnetospheric cyclotron maser. On the basis of this model, we have computed some discrete chorus emission parameters as well as magnetospheric parameters relevant to the generation process. A comparison of the computed and observed magnetospheric parameters has been presented. These results show a good agreement with the BWO model.

  12. Laboratory simulation of magnetospheric chorus wave generation

    Science.gov (United States)

    Van Compernolle, B.; An, X.; Bortnik, J.; Thorne, R. M.; Pribyl, P.; Gekelman, W.

    2017-01-01

    Whistler mode chorus emissions with a characteristic frequency chirp are important magnetospheric waves, responsible for the acceleration of outer radiation belt electrons to relativistic energies and also for the scattering loss of these electrons into the atmosphere. A laboratory experiment (Van Compernolle et al 2015 Phys. Rev. Lett. 114 245002, An et al 2016 Geophys. Res. Lett.) in the large plasma device at UCLA was designed to closely mimic the scaled plasma parameters observed in the inner magnetosphere, and shed light on the excitation of discrete frequency whistler waves. It was observed that a rich variety of whistler wave emissions is excited by a gyrating electron beam. The properties of the whistler emissions depend strongly on plasma density, beam density and magnetic field profiles.

  13. Hepatoprotective Effects of Panus giganteus (Berk.) Corner against Thioacetamide- (TAA-) Induced Liver Injury in Rats.

    Science.gov (United States)

    Wong, Wei-Lun; Abdulla, Mahmood Ameen; Chua, Kek-Heng; Kuppusamy, Umah Rani; Tan, Yee-Shin; Sabaratnam, Vikineswary

    2012-01-01

    Panus giganteus, a culinary and medicinal mushroom consumed by selected indigenous communities in Malaysia, is currently being considered for large scale cultivation. This study was undertaken to investigate the hepatoprotective effects of P. giganteus against thioacetamide- (TAA-) induced liver injury in Sprague-Dawley rats. The rats were injected intraperitoneally with TAA thrice weekly and were orally administered freeze-dried fruiting bodies of P. giganteus (0.5 or 1 g/kg) daily for two months, while control rats were given vehicle or P. giganteus only. After 60 days, rats administered with P. giganteus showed lower liver body weight ratio, restored levels of serum liver biomarkers and oxidative stress parameters comparable to treatment with the standard drug silymarin. Gross necropsy and histopathological examination further confirmed the hepatoprotective effects of P. giganteus. This is the first report on hepatoprotective effects of P. giganteus. The present study showed that P. giganteus was able to prevent or reduce the severity of TAA-induced liver injury.

  14. Hepatoprotective Effects of Panus giganteus (Berk. Corner against Thioacetamide- (TAA- Induced Liver Injury in Rats

    Directory of Open Access Journals (Sweden)

    Wei-Lun Wong

    2012-01-01

    Full Text Available Panus giganteus, a culinary and medicinal mushroom consumed by selected indigenous communities in Malaysia, is currently being considered for large scale cultivation. This study was undertaken to investigate the hepatoprotective effects of P. giganteus against thioacetamide- (TAA- induced liver injury in Sprague-Dawley rats. The rats were injected intraperitoneally with TAA thrice weekly and were orally administered freeze-dried fruiting bodies of P. giganteus (0.5 or 1 g/kg daily for two months, while control rats were given vehicle or P. giganteus only. After 60 days, rats administered with P. giganteus showed lower liver body weight ratio, restored levels of serum liver biomarkers and oxidative stress parameters comparable to treatment with the standard drug silymarin. Gross necropsy and histopathological examination further confirmed the hepatoprotective effects of P. giganteus. This is the first report on hepatoprotective effects of P. giganteus. The present study showed that P. giganteus was able to prevent or reduce the severity of TAA-induced liver injury.

  15. Production of Particleboards with Bamboo (Dendrocalamus giganteus Reinforcement

    Directory of Open Access Journals (Sweden)

    Ulysses José Zaia

    2015-01-01

    Full Text Available The focus of this research was to study the utilization of residues from bamboo (Dendrocalamus giganteus lamination in the manufacturing of panels for structural purposes. Bamboo particleboards were produced under three conditions: pure boards, reinforced with bamboo laminas, and with treated particles. Castor oil-based polyurethane was the resin binder, in view of using lower toxicity materials. The mechanical tests were performed according to Brazilian Standard (NBR 14810-3 (2006 and European Standard (EN 310 (2000. The results were superior to those recommended by these and other standards for internal adhesion resistance, modulus of rupture, and elasticity in static bending, as well as to the results of other studies. Starch treatment was an unnecessary stage. According to the conditions of this process, the studied panels showed a good potential for construction use. Moreover, the bamboo particleboards are an economically viable, environmentally friendly, and sustainable alternative for the use of waste generated during the processing of Dendrocalamus giganteus bamboo species, allied with castor oil-based polyurethane resin. The reinforced particleboard and its production process are being licensed as an Innovation Patent in Brazil, (BR 1020130133919-1-2013.

  16. Monotest in the complement fixation test: the Chorus system

    Directory of Open Access Journals (Sweden)

    Laura Meli

    2009-06-01

    Full Text Available The complement fixation test (CFT is a method used for the detection of antibodies against pathogens of infectious diseases, it has been proved to be a useful diagnostic method in the detection of acute disease in many medical laboratories.The test performed manually is time consuming and needs very skilled personnel.This study evaluates the automated Chorus CFT system with 87 serum samples in comparison with manual method using Virion-Serion reagents, against a panel of antigens, such as Adenovirus, Influenza A and B virus, Respiratory Syncythial Virus, Parainfluenza Mix, Mycoplasma Pneumoniae, and Echinococcus. The Chorus system includes standardized reagents and a monotest device to perform the single assay. In comparison to the manual CFT method, the correlation is 91.6% (7/83.The results obtained show that the automated Chorus system can be applied for detecting complement fixation antibodies against different infectious disease agents.

  17. Chorusing, synchrony and the evolutionary functions of rhythm

    Directory of Open Access Journals (Sweden)

    Andrea eRavignani

    2014-10-01

    Full Text Available A central goal of biomusicology is to understand the biological basis of human musicality. One approach to this problem has been to compare core components of human musicality (relative pitch perception, entrainment, etc. with similar capacities in other animal species. Here we extend and clarify this comparative approach with respect to rhythm. First, whereas most comparisons between human music and animal acoustic behavior have focused on spectral properties (melody and harmony, we argue for the central importance of temporal properties, and propose that this domain is ripe for further comparative research. Second, whereas most rhythm research in non-human animals has examined animal timing in isolation, we consider how chorusing dynamics can shape individual timing, as in human music and dance, making group behavior key to understand the adaptive functions of rhythm. To illustrate the interdependence between individual and chorusing dynamics, we present a computational model of chorusing agents relating individual call timing with synchronous group behavior. Third, we distinguish and clarify mechanistic and functional explanations of rhythmic phenomena, often conflated in the literature, arguing that this distinction is key for understanding the evolution of musicality. Fourth, we expand biomusicological discussions beyond the species typically considered, providing an overview of chorusing and rhythmic behavior across a broad range of taxa (orthopterans, fireflies, frogs, birds, and primates. Finally, we propose an Evolving Signal Timing hypothesis, suggesting that similarities between timing abilities in biological species will be based on comparable chorusing behaviors. We conclude that the comparative study of chorusing species can provide important insights into the adaptive function(s of rhythmic behavior in our proto-musical primate ancestors, and thus inform our understanding of the biology and evolution of rhythm in human music and

  18. Chorusing, synchrony, and the evolutionary functions of rhythm.

    Science.gov (United States)

    Ravignani, Andrea; Bowling, Daniel L; Fitch, W Tecumseh

    2014-01-01

    A central goal of biomusicology is to understand the biological basis of human musicality. One approach to this problem has been to compare core components of human musicality (relative pitch perception, entrainment, etc.) with similar capacities in other animal species. Here we extend and clarify this comparative approach with respect to rhythm. First, whereas most comparisons between human music and animal acoustic behavior have focused on spectral properties (melody and harmony), we argue for the central importance of temporal properties, and propose that this domain is ripe for further comparative research. Second, whereas most rhythm research in non-human animals has examined animal timing in isolation, we consider how chorusing dynamics can shape individual timing, as in human music and dance, arguing that group behavior is key to understanding the adaptive functions of rhythm. To illustrate the interdependence between individual and chorusing dynamics, we present a computational model of chorusing agents relating individual call timing with synchronous group behavior. Third, we distinguish and clarify mechanistic and functional explanations of rhythmic phenomena, often conflated in the literature, arguing that this distinction is key for understanding the evolution of musicality. Fourth, we expand biomusicological discussions beyond the species typically considered, providing an overview of chorusing and rhythmic behavior across a broad range of taxa (orthopterans, fireflies, frogs, birds, and primates). Finally, we propose an "Evolving Signal Timing" hypothesis, suggesting that similarities between timing abilities in biological species will be based on comparable chorusing behaviors. We conclude that the comparative study of chorusing species can provide important insights into the adaptive function(s) of rhythmic behavior in our "proto-musical" primate ancestors, and thus inform our understanding of the biology and evolution of rhythm in human music and

  19. On the numerical modelling of VLF chorus dynamical spectra

    Directory of Open Access Journals (Sweden)

    D. Nunn

    2009-06-01

    Full Text Available This paper presents a study of the use of a one-dimensional Vlasov Hybrid Simulation (VHS computer code to simulate the dynamical spectra (i.e. frequency versus time spectrograms of ELF/VLF chorus signals (from ~a fraction to ~10 kHz. Recently excellent measurements of chorus have been made in the source region close to the geomagnetic equator aboard the four spacecraft Cluster mission. Using Cluster data for wave amplitude, which is up to 300 pT, local gyrofrequency, cold plasma density, and L-shell, observed chorus signals are reproduced with remarkable fidelity and, in particular, sweep rates in the range 1–10 kHz result as observed. Further, we find that the sweep rate is a falling function of increasing cold plasma density, again in accord with observations. Finally, we have satisfactorily simulated the rather rare falling frequency elements of chorus which are sometimes observed aboard Cluster in the generation region. For both rising and falling chorus we have presented detailed structural analyses of the generation regions. The main contributor to the frequency sweep rate is primarily the establishment of wave number/frequency gradients across the generation region by the out of phase component of the resonant particle current. The secondary contributor is the shortening of the wavelength of resonant particle current relative to that of the wave field. In view of the close agreement between observation and simulation, we conclude that nonlinear electron cyclotron resonance is indeed the mechanism underlying the generation of chorus signals just outside the plasmasphere.

  20. Generation of Multiband Chorus in the Earth's Magnetosphere: 1-D PIC Simulation

    Science.gov (United States)

    Gao, Xinliang; Ke, Yangguang; Lu, Quanming; Chen, Lunjin; Wang, Shui

    2017-01-01

    Multiband chorus waves, where the frequency of upper band chorus is about twice that of lower band chorus, have recently been reported based on THEMIS observations. The generation of multiband chorus waves is attributed to the mechanism of lower band cascade, where upper band chorus is excited via the nonlinear coupling process between lower band chorus and the associated density mode with the frequency equal to that of lower band chorus. In this letter, with a one-dimensional (1-D) particle-in-cell (PIC) simulation model, we have successfully reproduced multiband chorus waves. During the simulation, the significant density fluctuation is driven by the fluctuating electric field along the wave vector of the pump wave (lower band chorus), which can be directly observed in this self-consistent plasma system. Then, the second harmonic of the pump whistler-mode wave (upper band chorus) is generated. After quantitatively analyzing resonant conditions among wave numbers, we can confirm that the generation is caused due to the coupling between the pump wave and the density fluctuation along its wave vector. The third harmonic can also be excited through lower band cascade if the pump whistler-mode wave has a sufficiently large amplitude. Our simulation results not only provide a theoretical support to the mechanism of lower band cascade to generate multiband chorus but also propose a new pattern of evolution for whistler-mode waves in the Earth's magnetosphere.

  1. Habitat preferences of coral-associated wentletrap snails (Gastropoda: Epitoniidae)

    NARCIS (Netherlands)

    Gittenberger, A.; Hoeksema, B.W.

    2013-01-01

    Examination of about 60,000 scleractinian corals of the families Dendrophylliidae, Euphylliidae and Fungiidae for the presence of associated wentletrap snails (Gastropoda: Epitoniidae) revealed various ectoparasitic life history strategies. Twenty Indo-Pacific wentletrap species were found, which we

  2. Generation mechanism of whistler-mode chorus emissions

    Science.gov (United States)

    Omura, Yoshiharu

    We describe the nonlinear dynamics of resonant electrons interacting with a coherent whistler-mode wave and the formation of electromagnetic electron holes or hills in the velocity phase space. In the presence of the inhomogeneity due to the frequency variation and the gradient of the magnetic field, the electron holes or hills result in resonant currents generating rising-tone emissions (1, 2) or falling-tone emissions (3), respectively. After formation of a coherent wave at the maximum linear growth rate, triggering of the nonlinear wave growth takes place when the wave amplitude is close to the optimum wave amplitude (4). The wave amplitude also has to be above the threshold amplitude (2) so that the nonlinear wave growth can occur as an absolute instability at the magnetic equator. The triggering process is repeated at progressively higher frequencies in the case of a rising-tone emission, generating subpackets of a chorus element. We also describe the mechanism of nonlinear wave damping due to quasi-oblique propagation from the equator (2), which results in the formation of a gap at half the electron cyclotron frequency, separating a long rising-tone chorus emission into the upper-band and lower-band chorus emissions (5). *References (1) Y. Omura,Y. Katoh, and D. Summers, Theory and simulation of the generation of whistler-mode chorus, J. Geophys. Res., 113, A04223, 2008. (2) Y. Omura, , M. Hikishima, Y. Katoh, D. Summers, and S. Yagitani, Nonlinear mechanisms of lower band and upper band VLF chorus emissions in the magnetosphere, J. Geophys. Res., 114, A07217, 2009. (3) Nunn, D., and Y. Omura, A computational and theoretical analysis of falling frequency VLF emissions, J. Geophys. Res., 117, A08228, 2012. (4) Omura, Y., and D. Nunn, Triggering process of whistler mode chorus emissions in the magnetosphere, J. Geophys. Res., 116, A05205, 2011. (5) S. Kurita, Y. Katoh, Y. Omura, V. Angelopoulos, C. M. Cully, O. Le Contel, and H. Misawa, THEMIS observation of

  3. Chorus from Two Brain Hemispheres with Chinese Pentatonic Scale

    Institute of Scientific and Technical Information of China (English)

    WU Dan; YAO De-zhong

    2014-01-01

    In order to listen to brain activity as a piece of music, we proposed a scale-free brainwave music (SFBM) technology, which translates the scalp EEG into music notes according to the power law of both EEG and music. In this paper, the methodology was further extended to chorus music of two channels from the two hemispheres. Firstly, EEG data from two channels symmetrically located on the left and right hemispheres are translated into MIDI sequences by SFBM, respectively, where the EEG parameters modulate the pitch, duration and volume of each music note. Then, the two sequences are fiitered into a chorus of the Chinese pentatonic scale or the Western major scale. The resulted Chinese and Western music at different sleep stages illustrate distinct differences in harmony, and the music with Chinese pentatonic scale sounds more harmonious.

  4. Review of recent results from NOMAD and CHORUS

    CERN Document Server

    Meyer, J P

    2000-01-01

    NOMAD and CHORUS are two short baseline neutrino oscillation experiments searching for nu /sub mu / to nu /sub tau / oscillations in the CERN SPS wide band neutrino beam. CHORUS has analysed about 60% of the data and finds no tau /sup -/ candidate. A limit is set at P/sub osc/( nu /sub mu / to nu /sub tau /)<4.0*10/sup -4/ (90% C.L.). NOMAD has almost finished the analysis and sees no excess of events. A limit is set at P/sub osc/( nu /sub mu / to nu /sub tau /)<4.2*10 /sup -4/ (90% C.L.). Combining this two results with the unified approach one can set a limit at P/sub osc/( nu /sub mu / to nu /sub tau /)<1.3*10/sup -4/. (7 refs).

  5. The influence of co-cultivation on expression of the antifungal protein in Aspergillus giganteus.

    Science.gov (United States)

    Meyer, Vera; Stahl, Ulf

    2003-01-01

    The afp gene of Aspergillus giganteus encodes a small, highly basic polypeptide with antifungal activity, named Antifungal Protein (AFP). The protein is secreted by the mould and inhibits the growth of various filamentous fungi. In this paper we report that co-cultivation of A. giganteus with various microorganisms alters afp expression. It was found that co-cultivation modulates afp expression on the level of transcription, using a reporter system based on the beta-glucuronidase gene. The presence of Fusarium oxysporum triggered afp transcription whereas dual cultures of A. giganteus and A. niger resulted in suppression of afp transcription. Growth tests performed with several carbon and nitrogen sources, revealed that the influence of co-cultivation is strongly dependent on the medium composition.

  6. Augmentation and Maximization of Per-Capita Call Active Space Through Chorusing in Anuran Amphibians

    Science.gov (United States)

    Fox, James Henderson

    It is poorly understood why anuran males form choruses. Although various reasons have been proposed, empirical support is lacking. This study proposed, developed, and evaluated the chorus active space (CAS) augmentation theory, which states that anuran choruses are formed and organized so as to augment and maximize per-capita CAS beyond that which could be achieved by an isolated male. This study involved three phases. First, computer models of hypothetical choruses indicated that CAS, as defined, is necessarily augmented for chorusing males. These models provided the necessary information from which optimal interindividual distances (IIDs), corresponding to maximal CASs, could be estimated differentially for linear and planar chorus configurations. The second phase examined Acris crepitans and Hyla cinerea choruses for optimal intermale spacing. A. crepitans, which utilizes mixed chorus geometries (either linear or planar, depending on available resources), cannot optimize IID within any observed pond-type breeding site; however, observed spacing would be optimal along a stream bank, where chorusing often occurs, for a chorus population of 61, approximately the minimum value at which CAS characteristics are stabile. H. cinerea males, which form only planar choruses, space orders of magnitude closer than optimal. Suboptimal spacing in this species is understandable, considering the would-be size of an optimally spaced chorus. In the final phase of this study, a database of CAS-related data was compiled mostly from published sources and was examined for variable relationships predicted on the basis of CAS augmentation theory. The findings suggest that very few planar geometry species may maximize CAS; whereas, a much larger number of mixed geometry species, perhaps as well as linear geometry species, may maximize CAS. These findings loosely agree with the field study findings and suggest that CAS augmentation theory applies to at least a subset of anuran species and

  7. COMPARATIVE FOLIAR EPIDERMAL STUDIES IN CYMBOPOGON CITRATUS (STAPF. AND CYMBOPOGON GIGANTEUS (HOCHST. CHIOV. IN NIGERIA

    Directory of Open Access Journals (Sweden)

    Abayomi Ezekiel FOLORUNSO

    2007-08-01

    Full Text Available The foliar epidermal studies were carried out on Cymbopogon citratus and Cymbopogon giganteus with the aim of determining the patterns of variation in their epidermal characteristics and assessing their value in species identification and classification. The characters of diagnostic importance in the identification of C. citratus are the micro hairs, which are sparsely distributed in the adaxial epidermis and prickle hairs present in both abaxial and adaxial epidermis. The diagnostic character for C. giganteus is the papillae seen alongside their long cells.

  8. A Three-Dimensional Ray Tracing Study on Whistler-Mode Chorus During Geomagnetic Activities%A Three-Dimensional Ray Tracing Study on Whistler-Mode Chorus During Geomagnetic Activities

    Institute of Scientific and Technical Information of China (English)

    周庆华; 史建魁; 肖伏良

    2011-01-01

    A three-dimensional ray tracing study of a whistler-mode chorus is conducted for different geomagnetic activities by using a global core plasma density model. For the upperband chorus, the initial azimuthal wave angle affects slightly the projection of ray trajectories onto the plane (Z, √(x^2 + y^2)), but controls the longitudinal propagation. The trajectory of the upper-band chorus is strongly associated with the plasmapause and the magnetic local time (MLT) of chorus source region. For the high geomagnetic activity, the chorus trajectory moves inward together with the plasmapause. In the bulge region, the plasmapause extends outward, while the chorus trajectory moves outward together with the plasmapause. For moderately or high geomagnetic activity, the lower-band chorus suffers low hybrid resonance (LHR) reflection before it reaches the plasmapause, leading to a weak correlation with the geomagnetic activity and magnetic local time of the chorus source region. For low geomagnetic activity, the lower-band chorus may be reflected firstly at the plasmapause instead of suffering LHR reflection, exhibiting a propagation characteristic similar to that of the upper-band chorus. The results provide a new insight into the propagation characteristics of the chorus for different geomagnetic activities and contribute to further understanding of the acceleration of energetic electron by a chorus wave.

  9. The mid-high latitude whistler mode chorus waves observed around substorm onsets

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Using the data of LFEW/TC-2, we studied the dawn side chorus around substorm onsets during a strong geomagnetic storm in November 2004. During this storm, LFEW/TC-2 observed 14 dawnside chorus events. Nine of them were associated with substorms and occurred within 40 min around the substorm onsets. The fre-quencies of waves have a very good correlation with the half equatorial electron cyclotron frequencies. Chorus can be excited in the region near magnetic equato-rial plane and then propagate to the mid and high latitudes. When the wave fre-quencies reach the local lower hybrid frequencies, chorus can be reflected due to the lower hybrid resonance. The time delay between the chorus and its echo is about 28 min. Previous observations show that the chorus can propagate at most to the magnetic latitudes of 40°. LFEW/ TC-2 found for the first time that the chorus in space could propagate to the magnetic latitude of 70°. Since most of the previous chorus observations are made close to the magnetic equatorial plane, our results are important for the studies of excitation and propagation of whistler mode wave, and relevant relativistic electron acceleration in the magnetosphere.

  10. The mid-high latitude whistler mode chorus waves observed around substorm onsets

    Institute of Scientific and Technical Information of China (English)

    YANG JunYing; CAO JinBin; YAN ChunXiao; LI LiuYuan; MA YuDuan

    2008-01-01

    Using the data of LFEW/TC-2, we studied the dawn side chorus around substorm onsets during a strong geomagnetic storm in November 2004. During this storm, LFEW/TC-2 observed 14 dawnside chorus events. Nine of them were associated with substorms and occurred within 40 min around the substorm onsets. The fre-quencies of waves have a very good correlation with the half equatorial electron cyclotron frequencies. Chorus can be excited in the region near magnetic equato-rial plane and then propagate to the mid and high latitudes. When the wave fre-quencies reach the local lower hybrid frequencies, chorus can be reflected due to the lower hybrid resonance. The time delay between the chorus and its echo is about 28 min. Previous observations show that the chorus can propagate at most to the magnetic latitudes of 40°. LFEW/TC-2 found for the first time that the chorus in space could propagate to the magnetic latitude of 70°. Since most of the previous chorus observatlons are made close to the magnetic equatorial plane, our results are Important for the studies of excitation and propagation of whistler mode wave, and relevant relativistic electron acceleration in the magnetosphere.

  11. Standard Works for Chorus: "Ein Deutsches Requiem.""How Lovely Is Thy Dwelling Place."

    Science.gov (United States)

    Heffernan, Charles W.

    1983-01-01

    While high school choirs used to perform extended choral works, in recent years the emphasis has been on shorter works and unaccompanied chorus. Describes "A German Requiem" by Brahms and recommends performance of its fourth movement to develop the musical growth of a chorus. (CS)

  12. Evolution of chorus emissions into plasmaspheric hiss observed by Van Allen Probes

    Science.gov (United States)

    Zhou, Qinghua; Xiao, Fuliang; Yang, Chang; Liu, Si; He, Yihua; Wygant, J. R.; Baker, D. N.; Spence, H. E.; Reeves, G. D.; Funsten, H. O.

    2016-05-01

    The two classes of whistler mode waves (chorus and hiss) play different roles in the dynamics of radiation belt energetic electrons. Chorus can efficiently accelerate energetic electrons, and hiss is responsible for the loss of energetic electrons. Previous studies have proposed that chorus is the source of plasmaspheric hiss, but this still requires an observational confirmation because the previously observed chorus and hiss emissions were not in the same frequency range in the same time. Here we report simultaneous observations form Van Allen Probes that chorus and hiss emissions occurred in the same range ˜300-1500 Hz with the peak wave power density about 10-5 nT2/Hz during a weak storm on 3 July 2014. Chorus emissions propagate in a broad region outside the plasmapause. Meanwhile, hiss emissions are confined inside the plasmasphere, with a higher intensity and a broader area at a lower frequency. A sum of bi-Maxwellian distribution is used to model the observed anisotropic electron distributions and to evaluate the instability of waves. A three-dimensional ray tracing simulation shows that a portion of chorus emission outside the plasmasphere can propagate into the plasmasphere and evolve into plasmaspheric hiss. Moreover, hiss waves below 1 kHz are more intense and propagate over a broader area than those above 1 kHz, consistent with the observation. The current results can explain distributions of the observed hiss emission and provide a further support for the mechanism of evolution of chorus into hiss emissions.

  13. CHORUS – providing a scalable solution for public access to scholarly research

    Directory of Open Access Journals (Sweden)

    Howard Ratner

    2014-03-01

    Full Text Available CHORUS (Clearinghouse for the Open Research of the United States offers an open technology platform in response to the public access requirements of US federal funding agencies, researchers, institutions and the public. It is focused on five principal sets of functions: 'identification', 'preservation', 'discovery', 'access', and 'compliance' . CHORUS facilitates public access to peer-reviewed publications, after a determined embargo period (where applicable, for each discipline and agency. By leveraging existing tools such as CrossRef, FundRef and ORCID, CHORUS allows a greater proportion of funding to remain focused on research. CHORUS identifies articles that report on federally funded research and enables a reader to access the ‘best available version’ free of charge, via the publisher. It is a scalable solution that offers maximum efficiency for all parties by automating as much of the process as is possible. CHORUS launched in pilot phase in September 2013, and the production phase will begin in early 2014.

  14. Source location of chorus emissions observed by Cluster

    Directory of Open Access Journals (Sweden)

    M. Parrot

    Full Text Available One of the objectives of the Cluster mission is to study sources of various electromagnetic waves using the four satellites. This paper describes the methods we have applied to data recorded from the STAFF spectrum analyser. This instrument provides the cross spectral matrix of three magnetic and two electric field components. This spectral matrix is analysed to determine, for each satellite, the direction of the wave normal relative to the Earth’s magnetic field as a function of frequency and of time. Due to the Cluster orbit, chorus emissions are often observed close to perigee, and the data analysis determines the direction of these waves. Three events observed during different levels of magnetic activity are reported. It is shown that the component of the Poynting vector parallel to the magnetic field changes its sense when the satellites cross the magnetic equator, which indicates that the chorus waves propagate away from the equator. Detailed analysis indicates that the source is located in close vicinity of the plane of the geomagnetic equator.

    Key words. Magnetospheric physics (plasma waves and instabilities; storms and substorms; Space plasma physics (waves and instabilities

  15. Modelling substorm chorus events in terms of dispersive azimuthal drift

    Directory of Open Access Journals (Sweden)

    A. B. Collier

    2004-12-01

    Full Text Available The Substorm Chorus Event (SCE is a radio phenomenon observed on the ground after the onset of the substorm expansion phase. It consists of a band of VLF chorus with rising upper and lower cutoff frequencies. These emissions are thought to result from Doppler-shifted cyclotron resonance between whistler mode waves and energetic electrons which drift into a ground station's field of view from an injection site around midnight. The increasing frequency of the emission envelope has been attributed to the combined effects of energy dispersion due to gradient and curvature drifts, and the modification of resonance conditions and variation of the half-gyrofrequency cutoff resulting from the radial component of the ExB drift.

    A model is presented which accounts for the observed features of the SCE in terms of the growth rate of whistler mode waves due to anisotropy in the electron distribution. This model provides an explanation for the increasing frequency of the SCE lower cutoff, as well as reproducing the general frequency-time signature of the event. In addition, the results place some restrictions on the injected particle source distribution which might lead to a SCE.

    Key words. Space plasma physics (Wave-particle interaction – Magnetospheric physics (Plasma waves and instabilities; Storms and substorms

  16. Signal interactions and interference in insect choruses: singing and listening in the social environment.

    Science.gov (United States)

    Greenfield, Michael D

    2015-01-01

    Acoustic insects usually sing amidst conspecifics, thereby creating a social environment-the chorus-in which individuals communicate, find mates, and avoid predation. A temporal structure may arise in a chorus because of competitive and cooperative factors that favor certain signal interactions between neighbors. This temporal structure can generate significant acoustic interference among singers that pose problems for communication, mate finding, and predator detection. Acoustic insects can reduce interference by means of selective attention to only their nearest neighbors and by alternating calls with neighbors. Alternatively, they may synchronize, allowing them to preserve call rhythm and also to listen for predators during the silent intervals between calls. Moreover, males singing in choruses may benefit from reduced per capita predation risk as well as enhanced vigilance. They may also enjoy greater per capita attractiveness to females, particularly in the case of synchronous choruses. In many cases, however, the overall temporal structure of the chorus is only an emergent property of simple, pairwise interactions between neighbors. Nonetheless, the chorus that emerges can impose significant selection pressure on the singing of those individual males. Thus, feedback loops may occur and potentially influence traits at both individual and group levels in a chorus.

  17. Frequencies of wave packets of whistler-mode chorus inside its source region: a case study

    Directory of Open Access Journals (Sweden)

    O. Santolik

    2008-06-01

    Full Text Available Whistler-mode chorus is a structured wave emission observed in the Earth's magnetosphere in a frequency range from a few hundreds of Hz to several kHz. We investigate wave packets of chorus using high-resolution measurements recorded by the WBD instrument on board the four Cluster spacecraft. A night-side chorus event observed during geomagnetically disturbed conditions is analyzed. We identify lower and upper frequencies for a large number of individual chorus wave packets inside the chorus source region. We investigate how these observations are related to the central position of the chorus source which has been previously estimated from the Poynting flux measurements. We observe typical frequency bandwidths of chorus of approximately 10% of the local electron cyclotron frequency. Observed time scales are around 0.1 s for the individual wave packets. Our results indicate a lower occurrence probability for lower frequencies in the vicinity of the central position of the source compared to measurements recorded closer to the outer boundaries of the source. This is in agreement with recent research based on the backward wave oscillator theory.

  18. Decoding Group Vocalizations: The Acoustic Energy Distribution of Chorus Howls Is Useful to Determine Wolf Reproduction

    Science.gov (United States)

    López-Bao, José Vicente; Llaneza, Luis; Fernández, Carlos; Font, Enrique

    2016-01-01

    Population monitoring is crucial for wildlife management and conservation. In the last few decades, wildlife researchers have increasingly applied bioacoustics tools to obtain information on several essential ecological parameters, such as distribution and abundance. One such application involves wolves (Canis lupus). These canids respond to simulated howls by emitting group vocalizations known as chorus howls. These responses to simulated howls reveal the presence of wolf litters during the breeding period and are therefore often used to determine the status of wolf populations. However, the acoustic structure of chorus howls is complex and discriminating the presence of pups in a chorus is sometimes difficult, even for experienced observers. In this study, we evaluate the usefulness of analyses of the acoustic energy distribution in chorus howls to identify the presence of pups in a chorus. We analysed 110 Iberian wolf chorus howls with known pack composition and found that the acoustic energy distribution is concentrated at higher frequencies when there are pups vocalizing. We built predictive models using acoustic energy distribution features to determine the presence of pups in a chorus, concluding that the acoustic energy distribution in chorus howls can be used to determine the presence of wolf pups in a pack. The method we outline here is objective, accurate, easily implemented, and independent of the observer's experience. These advantages are especially relevant in the case of broad scale surveys or when many observers are involved. Furthermore, the analysis of the acoustic energy distribution can be implemented for monitoring other social canids that emit chorus howls such as jackals or coyotes, provides an easy way to obtain information on ecological parameters such as reproductive success, and could be useful to study other group vocalizations. PMID:27144887

  19. Bounce-Averaged Acceleration of Energetic Electrons by Whistler Mode Chorus in the Magnetosphere

    Institute of Scientific and Technical Information of China (English)

    XIAO Fu-Liang; CHEN Liang-Xu; ZHOU Qing-Hua; HE Hui-Yong; WEN Yong-Jun

    2007-01-01

    @@ We construct the bounce-averaged diffusion coefficients and study the bounce-averaged acceleration for energetic electrons in gyroresonance with whistler mode chorus. Numerical calculations have been performed for a band of chorus frequency distributed over a standard Gaussian spectrum specifically in the region near L = 4.5, where peaks of the electron phase space density occur. It is found that whistler mode chorus can efficiently accelerate electrons and can increase the phase space density at energies of about 1 MeV by more than one order of magnitude about one day, in agreement with the satellite observations during the recovery phase of magnetic storms.

  20. Tartu segakoor "Chorus Forselianus" esines Krakovis / Jan Willemson, Madis Linnamägi

    Index Scriptorium Estoniae

    Willemson, Jan

    2011-01-01

    Krakovis 1.-3.10. 2010 toimunud 2. koorilaulufestivalist „Cracovia Music Festival”, kus osales üheksa koori üle Euroopa. Eestit esindas festivalil B. G. Forseliuse Seltsi segakoor „Chorus Forselianus”

  1. Greek Chorus: an Ageless Voice%希腊合唱团:永恒的声音

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The chorus in an ancient Greek drama is typically composed of ten to fifteen men who rhythmically chant a dramatic refrain. They are viewed as one entity in the play as opposed to a group of people.

  2. A decade of innovation in pharmaceutical R&D: the Chorus model.

    Science.gov (United States)

    Owens, Paul K; Raddad, Eyas; Miller, Jeffrey W; Stille, John R; Olovich, Kenneth G; Smith, Neil V; Jones, Rosie S; Scherer, Joel C

    2015-01-01

    Chorus is a small, operationally independent clinical development organization within Eli Lilly and Company that specializes in drug development from candidate selection to clinical proof of concept. The mission of Chorus is to achieve proof of concept rapidly and at a low cost while positioning successful projects for 'pharma-quality' late-stage development. Chorus uses a small internal staff of experienced drug developers and a network of external vendors to design and implement chemistry, manufacturing and control processes, preclinical toxicology and biology, and Phase I/II clinical trials. In the decade since it was established, Chorus has demonstrated substantial productivity improvements in both time and cost compared to traditional pharmaceutical research and development. Here, we describe its development philosophy, organizational structure, operational model and results to date.

  3. Performance of the CHORUS lead-scintillating fiber calorimeter

    CERN Document Server

    Buontempo, S

    1997-01-01

    We report on the design and performance of the lead-scintillating fiber calorimeter of the CHORUS experiment, which searches for νμ-ντ oscillations in the CERN Wide Band Neutrino beam. Two of the three sectors in which the calorimeter is divided are made of lead and plastic scintillating fibers, and they represent the first large scale application of this technique for combined electromagnetic and hadronic calorimetry. The third sector is built using the sandwich technique with lead plates and scintillator strips and acts as a tail catcher for the hadronic energy flow. From tests performed at the CERN SPS and PS an energy resolution of σ(E)/E=(32.3±2.4)%/E(GeV)+(1.4±0.7)% was measured for pions, and σ(E)/E=(13.8±0.9)%/E(GeV)+(−0.2±0.4)% for electrons.

  4. Effect of Steam Explosion Pretreatment on the Specific Methane Yield of Miscanthus x giganteus

    OpenAIRE

    Franz Theuretzbacher; Javier Lizasoain; Simona Menardo; Paal Jahre Nilsen; Andreas Gronauer; Alexander Bauer

    2014-01-01

    A highly promising energy crop for biogas production can be Miscanthus x giganteus. It has multiple advantages, which include low soil requirements and the existence of genotypes adapted to dry conditions in comparison to other energy crops. Miscanthus cannot be used in the biogas plant without a pretreatment due to the recalcitrant nature of lignocelluloses. One of the most efficient pretreatment methods for lignocellulosic biomass is steam explosion. This includes heating the biomass...

  5. Observational evidence of generation mechanisms for very oblique lower band chorus using THEMIS waveform data

    Science.gov (United States)

    Gao, Xinliang; Mourenas, Didier; Li, Wen; Artemyev, Anton V.; Lu, Quanming; Tao, Xin; Wang, Shui

    2016-07-01

    Chorus waves are intense coherent whistler mode waves with frequency chirping which play a dual role in both loss and acceleration of radiation belt electrons in the Earth's magnetosphere. Although the generation of parallel chorus waves has been extensively studied by means of theory, simulations, and observations, the generation mechanism of very oblique chorus waves still remains a mystery. In this study, we have analyzed hundreds of very oblique discrete (rising or falling tone) lower band chorus events collected from 7 years of Time History of Events and Macroscale Interactions during Substorms (THEMIS) waveform data to investigate their potential generation mechanisms. Comparisons between wave normal angles directly measured onboard THEMIS in the dawn-day sector at L = 5-9 and inferred from theoretical models on the basis of measured wave characteristics (frequency sweep rate, mean frequency, and amplitude) show that these very oblique waves are more commonly generated through cyclotron resonance with anisotropic electron streams. However, a second generation mechanism via Landau resonance with low-energy electron beams seems to be also operating on the nightside at L 8.5. Moreover, very oblique lower band chorus waves with large frequency chirping rates or small magnetic field amplitudes are more likely excited via cyclotron resonance, while waves with small frequency chirping rates or large magnetic field amplitudes are preferentially generated through Landau resonance. This comprehensive statistical study provides interesting insight into the possible generation mechanisms of very oblique lower band chorus waves in the Earth's magnetosphere.

  6. Chorus source region localization in the Earth's outer magnetosphere using THEMIS measurements

    Directory of Open Access Journals (Sweden)

    O. Agapitov

    2010-06-01

    Full Text Available Discrete ELF/VLF chorus emissions, the most intense electromagnetic plasma waves observed in the Earth's radiation belts and outer magnetosphere, are thought to propagate roughly along magnetic field lines from a localized source region near the magnetic equator towards the magnetic poles. THEMIS project Electric Field Instrument (EFI and Search Coil Magnetometer (SCM measurements were used to determine the spatial scale of the chorus source localization region on the day side of the Earth's outer magnetosphere. We present simultaneous observations of the same chorus elements registered onboard several THEMIS spacecraft in 2007 when all the spacecraft were in the same orbit. Discrete chorus elements were observed at 0.15–0.25 of the local electron gyrofrequency, which is typical for the outer magnetosphere. We evaluated the Poynting flux and wave vector distribution and obtained chorus wave packet quasi-parallel propagation to the local magnetic field. Amplitude and phase correlation data analysis allowed us to estimate the characteristic spatial correlation scale transverse to the local magnetic field to be in the 2800–3200 km range.

  7. Effect of Chorus Latitudinal Distribution on Evolution of Outer Radiation Belt Electrons

    Institute of Scientific and Technical Information of China (English)

    XIAO Fuliang; LI Junqiu; TANG Lijun; HE Yihua; LI Jiangfan

    2009-01-01

    Primary result on the impact of the latitudinal distribution of whistler-mode chorus upon temporal evolution of the phase space density (PSD) of outer radiation belt energetic electrons was presented.We evaluate diffusion rates in pitch angle and momentum due to a band of chorus frequency distributed at a standard Gaussian spectrum,and solve a 2-D bounce-averaged momentum-pitch-angle Fokker-Planck equation at L=4.5.It is shown that chorus is effective in accelerating electrons and can increase PSD for energy of ~1 MeV by a factor of 10 or more in about one day,which is consistent with observation.Moreover,the latitudinal distribution of chorus has a great impact on the acceleration of electrons.As the latitudinal distribution increases,the efficient acceleration region extends from higher pitch angles to lower pitch angles,and even covers the entire pitch angle region when chorus power reaches the maximum latitude λm=45°.

  8. Emergence of Electron Distributions Related to Banded Chorus Excitation

    Science.gov (United States)

    Liu, K.; Min, K.; Fu, X.; Gary, S. P.; Winske, D.; Cowee, M.

    2014-12-01

    Two-dimensional electromagnetic particle-in-cell simulations are performed to investigate the emergence of electron velocity distributions with an "anisotropy gap" in the radiation belts. Such distributions have been shown to be able to excite banded chorus as anisotropic electrons with T⊥/T||>1 at different T|| , where || and ⊥ denote directions relative to the background geomagnetic field, can drive the whistler anisotropy instability in the upper- and lower-bands, independently. Energy-dependent convection and loss of the electrons in the radiation belts can generally lead to anisotropic electrons which, subsequently, excite whistler waves. As a simplification of reality, the simulations in the present study start with an electron distribution which is constantly anisotropic at all energies. The anisotropic electrons lead to growth of whistlers in the system. The enhanced waves, in turn, scatter the electrons and reduce their anisotropy. Interestingly, the reduction of anisotropy is more dramatic for electrons with intermediate energies. An anisotropy gap arises as a natural consequence of the self-consistent wave-particle interactions and, in the quasi-steady phase of the simulations, produces the banded structure in the spectrum of the enhanced whistler waves.

  9. The SPS Target Station for CHORUS and NOMAD Neutrino Experiments

    CERN Document Server

    Péraire, S; Zazula, J M

    1996-01-01

    A new SPS target station, T9, has been constructed for the CHORUS and NOMAD neutrino experiments at CERN. The heart of the station is the target box : 11 beryllium rods are aligned in a cast aluminium box ; they are cooled by a closed circuit helium gas with adjusted flow to each rod. The box is motorised horizontally and vertically at both ends, to remotely optimise the secondary particle production by aligning the target with the incident proton beam. Radiation protection around the station is guaranteed by more than 100 tons of shielding material (iron, copper, marble). This presentation describes briefly the various components of the target station ; it emphasises particularly the thermal and mechanical calculations which define a safe maximum beam intensity on the beryllium rods. Over the first two years of successful operation, the station has received more than 2€1019 protons at 450 GeV/c, with intensity peaks of 2.8€1013 protons per machine cycle.

  10. Potential uses of biomass from fast-growing crop miscanthus×giganteus

    Directory of Open Access Journals (Sweden)

    Babović Nada V.

    2012-01-01

    Full Text Available There is an increasing interest in perennial grasses as a renewable source of bioenergy and feedstock for second-generation cellulosic biofuels. Switchgrass (Panicum virgatum and miscanthus (Miscanthus×giganteus, belonging to the parennial grasses group, are the major lignocellulosic materials being studied today as sources for direct energy production, biofuels, bioremediation and other. They have the ability to grow at low cost on marginal land where they will not compete with the traditional food crops. Miscanthus×giganteus possesses a number of advantages in comparison with the other potential energy crops such as are: high yields, low moisture content at harvest, high water and nitrogen use efficiencies, low need for annual agronomic inputs such as fertilizers and pesticides, high cellulose content, non-invasive character, low susceptibility to pests and diseases and broad adaptation to temperate growing environments. The main problems are low rate of survival during the first winter after the creation of plantation and the relatively high establishment costs. Miscanthus×giganteus is grown primarily for heat and electricity generation but can also be used to produce transport fuels. Miscanthus biomass has a very good combustion quality due to its low water concentration as well as its low Cl, K, N, S and ash concentrations compared to other lignocellulose plants. It is expected that miscanthus will provide cheaper and more sustainable source of cellulose for production of bioethanol than annual crops such as corn. Miscanthus has great promise as a renewable energy source, but it can only be realised when the grass production has been optimised for large-scale commercial cultivation. However, further research is still needed to optimise agronomy of miscanthus, to develop the production chain and pre-treatment as well as to optimise energy conversation route to produce heat, electricity, and/or fuels from biomass, if miscanthus is to

  11. Dawn chorus variation in East-Asian tropical montane forest birds and its ecological and morphological correlates

    NARCIS (Netherlands)

    Chen, W.-M.; Lee, Y.-F.; Tsai, C.-F.; Yao, C.-T.; Chen, Y.-H.; Li, S.-H.; Kuo, Y.-M.

    2015-01-01

    Many birds in breeding seasons engage in vigorous dawn singing that often turns to a prominent chorus. We examined dawn chorus variation of avian assemblages in a tropical montane forest in Taiwan and tested the hypothesis that onset sequence is affected by eye sizes, foraging heights, and diet of b

  12. Roosting behaviour and habitat selection of Pteropus giganteus reveals potential links to Nipah virus epidemiology.

    Science.gov (United States)

    Hahn, Micah B; Epstein, Jonathan H; Gurley, Emily S; Islam, Mohammad S; Luby, Stephen P; Daszak, Peter; Patz, Jonathan A

    2014-04-01

    1. Flying foxes Pteropus spp. play a key role in forest regeneration as seed dispersers and are also the reservoir of many viruses, including Nipah virus in Bangladesh. Little is known about their habitat requirements, particularly in South Asia. Identifying Pteropus habitat preferences could assist in understanding the risk of zoonotic disease transmission broadly, and in Bangladesh, could help explain the spatial distribution of human Nipah virus cases. 2. We analysed characteristics of Pteropus giganteus roosts and constructed an ecological niche model to identify suitable habitat in Bangladesh. We also assessed the distribution of suitable habitat in relation to the location of human Nipah virus cases. 3. Compared to non-roost trees, P. giganteus roost trees are taller with larger diameters, and are more frequently canopy trees. Colony size was larger in densely forested regions and smaller in flood-affected areas. Roosts were located in areas with lower annual precipitation and higher human population density than non-roost sites. 4. We predicted that 2-17% of Bangladesh's land area is suitable roosting habitat. Nipah virus outbreak villages were 2.6 times more likely to be located in areas predicted as highly suitable habitat for P. giganteus compared to non-outbreak villages. 5. Synthesis and applications. Habitat suitability modelling may help identify previously undocumented Nipah outbreak locations and improve our understanding of Nipah virus ecology by highlighting regions where there is suitable bat habitat but no reported human Nipah virus. Conservation and public health education is a key component of P. giganteus management in Bangladesh due to the general misunderstanding and fear of bats that are a reservoir of Nipah virus. Affiliation between Old World fruit bats (Pteropodidae) and people is common throughout their range, and in order to conserve these keystone bat species and prevent emergence of zoonotic viruses, it is imperative that we

  13. DIVERSITAS DAN KERAPATAN MANGROVE, GASTROPODA DAN BIVALVIA DI ESTUARI PERANCAK, BALI

    OpenAIRE

    2011-01-01

    Penelitian ini bertujuan membandingkan diversitas dan kerapatan mangrove dengan kepadatan gastropoda dan bivalvia di mangrove alami dan rehabilitasi. Pengukuran ekosistem mangrove menggunakan transek kuadrat 10 m x 10 m. Kelimpahan dan kepadatan gastropoda dan bialvia menggunakan transek kuadrat berukuran 1 m x 1 m. Analisis nMDS, cluster untuk melihat hubungan karekteristik mangrove alami dan rehabilitasi dianalisis secara deskriptif dan analisis regresi untuk mendetermi...

  14. Simultaneous disappearances of plasmaspheric hiss, exohiss, and chorus waves triggered by a sudden decrease in solar wind dynamic pressure

    Science.gov (United States)

    Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui; Spence, H. E.; Reeves, G. D.; Baker, D. N.; Blake, J. B.; Funsten, H. O.; Wygant, J. R.

    2017-01-01

    Magnetospheric whistler mode waves are of great importance in the radiation belt electron dynamics. Here on the basis of the analysis of a rare event with the simultaneous disappearances of whistler mode plasmaspheric hiss, exohiss, and chorus triggered by a sudden decrease in the solar wind dynamic pressure, we provide evidences for the following physical scenarios: (1) nonlinear generation of chorus controlled by the geomagnetic field inhomogeneity, (2) origination of plasmaspheric hiss from chorus, and (3) leakage of plasmaspheric hiss into exohiss. Following the reduction of the solar wind dynamic pressure, the dayside geomagnetic field configuration with the enhanced inhomogeneity became unfavorable for the generation of chorus, and the quenching of chorus directly caused the disappearances of plasmaspheric hiss and then exohiss.

  15. Studi Penilaian Ekosistem Mangrove Hasil Tanam Berdasarkan Keberadaan Gastropoda di Pulau Pramuka, Kepulauan Seribu, Jakarta

    Directory of Open Access Journals (Sweden)

    Yayan Mardiansyah Assuyuti

    2016-07-01

    Full Text Available The aims of mangrove replanted are to protect and good quality of coastal ecosystems and small islands, but it is have influenced to change of habitat and ecology function. This study conducted at Pramuka Island, Seribu islands, Jakarta, in June 2016. Data of gastropoda using 1 m2 square random sampling and divide depend on height are 0-1, 1-2 and 2-3 m. The aims of study are to determine (i diversity, density, (ii vertical distribution, (iii size shell, (iv correlation of density with distribution, (v correlation of size shell with vertical distribution, (vi correlation of individual with height gastropoda, and (vii assessment of mangrove replanted depend on gastropoda. The species of Terebralia sp. and Littorina sp. are found in mangrove replanted. The total value of diversity and density of mangrove gastropoda are 0.6 and 31.3 ind/m2, respectively. Vertical distribution of gastropoda Terebralia sp. found in 0-1 m and Littorina sp. in 0-3 m. The density and individual of Terebralia sp. have high value and size shell largest than Littorina sp. Gastropoda found indicated that the mangrove ecosystem in Pramuka island is still young and is in a transition state.

  16. Rapid flattening of butterfly pitch angle distributions of radiation belt electrons by whistler-mode chorus

    Science.gov (United States)

    Yang, Chang; Su, Zhenpeng; Xiao, Fuliang; Zheng, Huinan; Wang, Yuming; Wang, Shui; Spence, H. E.; Reeves, G. D.; Baker, D. N.; Blake, J. B.; Funsten, H. O.

    2016-08-01

    Van Allen radiation belt electrons exhibit complex dynamics during geomagnetically active periods. Investigation of electron pitch angle distributions (PADs) can provide important information on the dominant physical mechanisms controlling radiation belt behaviors. Here we report a storm time radiation belt event where energetic electron PADs changed from butterfly distributions to normal or flattop distributions within several hours. Van Allen Probes observations showed that the flattening of butterfly PADs was closely related to the occurrence of whistler-mode chorus waves. Two-dimensional quasi-linear STEERB simulations demonstrate that the observed chorus can resonantly accelerate the near-equatorially trapped electrons and rapidly flatten the corresponding electron butterfly PADs. These results provide a new insight on how chorus waves affect the dynamic evolution of radiation belt electrons.

  17. Signal recognition by frogs in the presence of temporally fluctuating chorus-shaped noise.

    Science.gov (United States)

    Vélez, Alejandro; Bee, Mark A

    2010-10-01

    The background noise generated in large social aggregations of calling individuals is a potent source of auditory masking for animals that communicate acoustically. Despite similarities with the so-called "cocktail-party problem" in humans, few studies have explicitly investigated how non-human animals solve the perceptual task of separating biologically relevant acoustic signals from ambient background noise. Under certain conditions, humans experience a release from auditory masking when speech is presented in speech-like masking noise that fluctuates in amplitude. We tested the hypothesis that females of Cope's gray treefrog (Hyla chrysoscelis) experience masking release in artificial chorus noise that fluctuates in level at modulations rates characteristic of those present in ambient chorus noise. We estimated thresholds for recognizing conspecific advertisement calls (pulse rate=40-50 pulses/s) in the presence of unmodulated and sinusoidally amplitude modulated (SAM) chorus-shaped masking noise. We tested two rates of modulation (5 Hz and 45 Hz) because the sounds of frog choruses are modulated at low rates (e.g., less than 5-10 Hz), and because those of species with pulsatile signals are additionally modulated at higher rates typical of the pulse rate of calls (e.g., between 15-50 Hz). Recognition thresholds were similar in the unmodulated and 5-Hz SAM conditions, and 12 dB higher in the 45-Hz SAM condition. These results did not support the hypothesis that female gray treefrogs experience masking release in temporally fluctuating chorus-shaped noise. We discuss our results in terms of modulation masking, and hypothesize that natural amplitude fluctuations in ambient chorus noise may impair mating call perception.

  18. Observations and modeling of forward and reflected chorus waves captured by THEMIS

    Directory of Open Access Journals (Sweden)

    O. Agapitov

    2011-03-01

    Full Text Available Discrete ELF/VLF chorus emissions are the most intense electromagnetic plasma waves observed in the radiation belts of the Earth's magnetosphere. Chorus emissions, whistler-mode wave packets propagating roughly along magnetic field lines from a well-localized source in the vicinity of the magnetic equator to polar regions, can be reflected at low altitudes. After reflection, wave packets can return to the equatorial plane region. Understanding of whistler wave propagation and reflection is critical to a correct description of wave-particle interaction in the radiation belts. We focus on properties of reflected chorus emissions observed by the THEMIS (Time History of Events and Macroscale Interactions During Substorms spacecraft Search Coil Magnetometer (SCM and Electric Field Instrument (EFI at ELF/VLF frequencies up to 4 kHz at L≥8. We determine the direction of the Poynting flux and wave vector distribution for forward and reflected chorus waves. Although both types of chorus waves were detected near the magnetic equator and have similar, discrete structure and rising tones, reflected waves are attenuated by a factor of 10–30 and have 10% higher frequency than concurrently-observed forward waves. Modeling of wave propagation and reflection using geometrical optics ray-tracing allowed us to determine the chorus source region location and explain observed propagation characteristics. We find that reflected wave attenuation at a certain spatial region is caused by divergence of the ray paths of these non-ducted emissions, and that the frequency shift is caused by generation of the reflected waves at lower L-shells where the local equatorial gyrofrequency is larger.

  19. Two new records of Pyramidellidae (Gastropoda, Heterobranchia) from China seas

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhiyun; ZHANG Suping

    2011-01-01

    This paper reports two species of the family Pyramidellidae (Gastropoda,Heterobranchia),Otopleura nitida (A.Adams,1854) and Rugadentia manzakiana (Yokoyama,1922).The former was from the South China Sea and the latter was from the Yellow Sea and East China Sea.The study was based on the collections deposited in the Marine Biological Museum,Chinese Academy of Sciences.This is for the first time that these species have been recorded in China seas.In the current contribution,we describe and illustrate these two species,and compare them with similar species.

  20. Nonlinear sub-cyclotron resonance as a formation mechanism for gaps in banded chorus

    CERN Document Server

    Fu, Xiangrong; Dong, Chuanfei; Gary, S Peter

    2015-01-01

    An interesting characteristic of magnetospheric chorus is the presence of a frequency gap at $\\omega \\simeq 0.5\\Omega_e$, where $\\Omega_e$ is the electron cyclotron angular frequency. Recent chorus observations sometimes show additional gaps near $0.3\\Omega_e$ and $0.6\\Omega_e$. Here we present a novel nonlinear mechanism for the formation of these gaps using Hamiltonian theory and test-particle simulations in a homogeneous, magnetized, collisionless plasma. We find that an oblique whistler wave with frequency at a fraction of the electron cyclotron frequency can resonate with electrons, leading to effective energy exchange between the wave and particles.

  1. Preliminary Assessment of Tecplot Chorus for Analyzing Ensemble of CTH Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Agelastos, Anthony Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stevenson, Joel O. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Attaway, Stephen W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Peterson, David

    2015-04-01

    The exploration of large parameter spaces in search of problem solution and uncertainty quantifcation produces very large ensembles of data. Processing ensemble data will continue to require more resources as simulation complexity and HPC platform throughput increase. More tools are needed to help provide rapid insight into these data sets to decrease manual processing time by the analyst and to increase knowledge the data can provide. One such tool is Tecplot Chorus, whose strengths are visualizing ensemble metadata and linked images. This report contains the analysis and conclusions from evaluating Tecplot Chorus with an example problem that is relevant to Sandia National Laboratories.

  2. Growth characteristics and nutrient depletion of Miscanthus x ogiformis Honda 'Giganteus' suspension cultures

    DEFF Research Database (Denmark)

    Holme, Inger Bæksted

    1998-01-01

    The growth characteristics and nutrient depletion in suspension cultures of Miscanthus ogiformis Honda ‘Giganteus' grown in media containing either Murashige and Skoog or N6 basal nutrient salts were studied during a culture period of 15 days. Proline was added to both media in concentrations from...

  3. Vigas de concreto reforçadas com bambu Dendrocalamus giganteus. I: análise experimental Concrete beams reinforced with bamboo (Dendrocalamus giganteus. I: experimental analysis

    Directory of Open Access Journals (Sweden)

    Humberto C. Lima Júnior

    2005-12-01

    Full Text Available Neste trabalho, apresenta-se e se discute um estudo experimental sobre o comportamento estrutural de vigas de concreto reforçadas com bambu. Ensaiaram-se dez vigas de concreto armado, sendo oito vigas armadas longitudinalmente com varas de bambu Dendrocalamus giganteus e duas vigas de referência, armadas com barras de aço. Duas variáveis foram estudadas: a taxa de armadura longitudinal (1,6 e 3,2% e a relação área/perímetro das varas de bambu (0,25 e 0,33 cm. Para cada combinação de variáveis foram confeccionadas duas vigas. Curvas força vs. deslocamento e força vs. deformação dos materiais são apresentadas e discutidas. Constatou-se que o comportamento estrutural das vigas de concreto reforçadas com bambu segue a teoria de flexão de Bernoulli-Kirchoff, sendo possível a aplicação dos procedimentos usuais de dimensionamento do concreto armado no projeto desses elementos. Observou-se, também, que a capacidade de carga dessas vigas se assemelha à das vigas de aço; contudo, estas são mais rígidas que aquelas.In this paper, an experimental study about bamboo reinforced concrete beams is presented and discussed. Ten reinforced concrete beams were tested, where eight of them were reinforced with Dendrocalamus giganteus bamboo-splint and two reference beams were reinforced with steel bars. Two factors were studied: the longitudinal reinforcement ratio (1.6 and 3.2% and the area/perimeter ratio of the bamboo-splint (0.25 and 0.33 cm. For each factor combination, two beams were cast. Force vs. displacement and force vs. strain curves are presented and discussed. It was found out that the structural behaviour of bamboo-concrete beams follow the Bernoulli-Kirchoff bending theory. Therefore, the usual design procedures of reinforced concrete can be used to design the bamboo-concrete beams. The load capacity of the bamboo-concrete beams is almost the same as that of reinforced with steel; nevertheless, are more stiffer than those

  4. Student Voice Use and Vocal Health during an All-State Chorus Event

    Science.gov (United States)

    Daugherty, James F.; Manternach, Jeremy N.; Price, Kathy K.

    2011-01-01

    This field-based case study documented students' (N = 256) voice use and voice health perceptions during a 3-day all-state high school chorus event through daily surveys, phonation duration data, analysis of rehearsal voice use behaviors, and field notes. Among the primary results are the following: (a) First and final day survey comparisons…

  5. 合唱艺术中的音色问题%The Timbre in Chorus

    Institute of Scientific and Technical Information of China (English)

    杜勇

    2011-01-01

    The art of Chorus is a kind of vocal music manifestation which uses voice to express music works, and a kind of "vocal symphonic music" genre which has very rich expressive capacity. Chorus is a collective music performance and music of multi - vocal - parts. What it emphasizes are balance, harmony, and general character. The present form of chorus focuses on "four mixed vocal parts", requiring that each part has different characteristics, different timbre. The timbre plays an important role in chorus and cannot be neglected.%合唱艺术是用人声来表现音乐作品的声乐表现形式,也是一种表现力极为丰富的“声乐交响”音乐体裁。合唱是集体音乐的表演,是多声部的音乐,强调的是均衡、和谐、共性。现在的合唱形式普遍以“混声四部”合唱为主,要求每个声部都有不同的特点,不同的音色,音色在合唱中起着重要的作用,是不能忽视的。

  6. Singing the Praise of Hong Kong’s Return——A Hong Kong chorus visits Beijing

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    AN 82-member Hong Kong chorus recently held a concert in Beijing to express their happiness at Hong Kong’s return to China. The Hong Kong Arts Chorus entitled their concert, "When the wind sweeps through, paddy fields produce fragrance to merge both banks--hail the return of Hong Kong." The verse which the chorus had adopted as the title of their concert in Beijing comes from a well-known song on the mainland,"My Motherland." By adopting this famous

  7. High Resolution Spectral Analysis of Hiss and Chorus Emissions in Ground Based Data

    Science.gov (United States)

    Hosseini Aliabad, S. P.; Golkowski, M.; Gibby, A. R.

    2015-12-01

    The dynamic evolution of the radiation belts is believed to be controlled in large part by two separate but related classes of naturally occurring plasma waves: ELF/VLF chorus and hiss emissions. Although whistler mode chorus has been extensively studied since the first reports by Storey in 1953, the source mechanism and properties are still subjects of active research. Moreover, the origin of plasmaspheric hiss, the electromagnetic emission believed to be responsible for the gap between the inner and outer radiation belts, has been debated for over four decades. Although these waves can be observed in situ on spacecraft, ground-based observing stations can provide orders of magnitude higher data volumes and decades long data coverage essential for certain long-term and statistical studies of wave properties. Recent observational and theoretical works suggest that high resolution analysis of the spectral features of both hiss and chorus emissions can provide insight into generation processes and be used to validate existing theories. Application of the classic Fourier (FFT) technique unfortunately yields a tradeoff between time and frequency resolution. In additional to Fourier spectra, we employ novel methods to make spectrograms with high time and frequency resolutions, independently using minimum variance distortionless response (MVDR). These techniques are applied to ground based data observations of hiss and chorus made in Alaska. Plasmaspheric hiss has been widely regarded as a broadband, structure less, incoherent emission. We quantify the extent to which plasmaspheric hiss can be a coherent emission with complex fine structure. Likewise, to date, researchers have differentiated between hiss and chorus coherency primarily using qualitative "naked eye" approaches to amplitude spectra. Using a quantitative approach to observed amplitude and we present more rigorous classification criteria for these emissions.

  8. Electron acceleration at Jupiter: input from cyclotron-resonant interaction with whistler-mode chorus waves

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    2013-10-01

    Full Text Available Jupiter has the most intense radiation belts of all the outer planets. It is not yet known how electrons can be accelerated to energies of 10 MeV or more. It has been suggested that cyclotron-resonant wave-particle interactions by chorus waves could accelerate electrons to a few MeV near the orbit of Io. Here we use the chorus wave intensities observed by the Galileo spacecraft to calculate the changes in electron flux as a result of pitch angle and energy diffusion. We show that, when the bandwidth of the waves and its variation with L are taken into account, pitch angle and energy diffusion due to chorus waves is a factor of 8 larger at L-shells greater than 10 than previously shown. We have used the latitudinal wave intensity profile from Galileo data to model the time evolution of the electron flux using the British Antarctic Survey Radiation Belt (BAS model. This profile confines intense chorus waves near the magnetic equator with a peak intensity at ∼5° latitude. Electron fluxes in the BAS model increase by an order of magnitude for energies around 3 MeV. Extending our results to L = 14 shows that cyclotron-resonant interactions with chorus waves are equally important for electron acceleration beyond L = 10. These results suggest that there is significant electron acceleration by cyclotron-resonant interactions at Jupiter contributing to the creation of Jupiter's radiation belts and also increasing the range of L-shells over which this mechanism should be considered.

  9. Dermoglyphus giganteus sp, nov. : eine neue Art der Federmilben aus der Familie Dermoglyphidae (Astigmata, Analgoidea) vom Sperlingstäubchen Columbigal/ina passerina (Aves, Columbiformes)

    OpenAIRE

    Dabert, Jacek; Ehrnsberger, Rainer

    2012-01-01

    Es wird die neue Art Dermoglyphus giganteus sp.n. aus der Federmilbenfamilie Dermoglyphidae (Astigmata, Analgoidea) vom Sperlingstäubchen Collumbigallina passerina (Columbiformes) beschrieben. Es werden Angaben zum Mikrohabitat und zur Lebensweise dieser Art gemacht. The new species Dermoglyphus giganteus sp.n. of the feather mite family Dermoglyphidae (Astigmata, Analgoidea) from the Common Ground-Dove Columbigallina passerina (Columbiformes) is described. The life conditions and microha...

  10. Comparing the performance of Miscanthus x giganteus and wheat straw biomass in sulfuric acid based pretreatment.

    Science.gov (United States)

    Kärcher, M A; Iqbal, Y; Lewandowski, I; Senn, T

    2015-03-01

    The objective of this study was to assess and compare the suitability of Miscanthus x giganteus and wheat straw biomass in dilute acid catalyzed pretreatment. Miscanthus and wheat straw were treated in a dilute sulfuric acid/steam explosion pretreatment. As a result of combining dilute sulfuric acid- and steam explosion pretreatment the hemicellulose hydrolysis yields (96% in wheat straw and 90% in miscanthus) in both substrates were higher than reported in literature. The combined severity factor (=CSF) for optimal hemicellulose hydrolysis was 1.9 and 1.5 in for miscanthus and wheat straw respectively. Because of the higher CSF value more furfural, furfuryl alcohol, 5-hydroxymethylfurfural and acetic acid was formed in miscanthus than in wheat straw pretreatment.

  11. EVALUATION OF FIBER DIMENSIONS OF Dendrocalamus giganteus (Wall Munro BAMBOO CULMS AT DIFFERENT AGES

    Directory of Open Access Journals (Sweden)

    Nelson Potenciano Marinho

    2014-03-01

    Full Text Available http://dx.doi.org/10.5902/1980509813342This study aimed to evaluate the fiber dimension of Dendrocalamus giganteus culms in 2-6 years old. Samples from basal portion of culms were macerated and sliced in sliding microtome for dimension fibers evaluation and histological cut production. Results showed that fibers increased in length with culms age, being the smallest and the biggest lengths 3266 and 3878.57 μm, observed in 3º and 6º years, respectively. The fibers showed smaller and bigger wall thickness in 6º and 2º years, with value of 7.11 and 10.46 μm, respectively. The anatomical tissue of culms varied from 12.8, 47.6 and 39.6 for vascular bundles, fibers and parenchyma, respectively.

  12. The effect of daytime rain on the Indian Flying Fox (Mammalia: Chiroptera: Pteropodidae Pteropus giganteus

    Directory of Open Access Journals (Sweden)

    S. Baskaran

    2016-02-01

    Full Text Available Excessive water loss during the day due to heat stress in bats of the genus Pteropus appears to be inevitable, because these bats are exposed to direct sunlight.  Rain also affects the rest pattern of the Indian Flying Fox Pteropus giganteus during the day.  When rain occurred during the day, most of the bats hung in a slanting position and did not exhibit any movements.  After rain, they licked both ventral and dorsal surfaces of the wing membrane and scratched their body with their thumb claws.  They also licked the water droplets that remained on the leaves and branches of the tree.  Even though their rest had been affected by the rain the bats utilized the water droplets to quench their thirst, cool their body and clean their fur.  The construction of water reservoirs near Pteropus roosts will help to assure their long-term conservation. 

  13. Increased metal concentrations in giant sungazer lizards (Smaug giganteus) from mining areas in South Africa.

    Science.gov (United States)

    McIntyre, Trevor; Whiting, Martin J

    2012-11-01

    Environmental contaminants from anthropogenic activity such as mining can have profound health effects on the animals living in adjacent areas. We investigated whether inorganic contaminants associated with gold-mining waste discharges were accumulated by a threatened species of lizard, Smaug giganteus, in South Africa. Lizards were sampled from two mining sites and two control sites. Blood samples from the most contaminated mining site had significantly greater concentrations of lithium, sodium, aluminum, sulfur, silicon, chromium, manganese, iron, nickel, copper, tungsten, and bismuth than the remaining sites. Contaminant concentrations were not significantly related to lizard body condition, although these relationships were consistently negative. The adult sex ratio of the population inhabiting the most contaminated site also deviated from an expected 1:1 ratio in favour of female lizards. We demonstrate that lizards at these mining sites contained high concentrations of heavy metals that may be imposing as yet poorly understood costs to these lizards.

  14. Diversity and taxonomy of Vietnamese Pollicaria (Gastropoda, Pupinidae

    Directory of Open Access Journals (Sweden)

    Russell L. Minton

    2017-02-01

    Full Text Available Species in the genus Pollicaria (Gastropoda: Pupinidae are conspicuous members of the southeast Asian land snail fauna. Originally erected in 1856, both the genus and its constituent species have been reorganized multiple times with the most recent treatment published in 2013. Collections of Vietnamese Pollicaria during 2014 and 2015 raised questions of the utility of currently used diagnostic shell characters and identification keys in species identification. An examination of the authors’ collections, combined with museum specimens, suggested that at least three species of Pollicaria occur or have historically occurred in Vietnam. It is suggested that P. rochebruni is a senior synonym of P. crossei and treat both taxa as conspecific. A second species, P. mouhoti, was believed to only occur in Cambodia, Laos, and Thailand. A possible third species, based only on previous karyotypic work, is discussed. Our data further suggest that shell features such as color and size lack consistent utility in species-level identifications in Pollicaria.

  15. Solar Wind Compression Generation of Coincident EMIC and Whistler Mode Chorus and Hiss Waves

    Science.gov (United States)

    Halford, Alexa; Mann, Ian

    2016-07-01

    Electron radiation belt dynamics are controlled by the competition of multiple acceleration and loss mechanisms. Electromagnetic ion cyclotron (EMIC), chorus, and hiss waves have all been implicated as potential loss mechanisms of radiation belt electrons along with Chorus waves proposed as a mechanism for accelerating the lower energy source population to MeV energies. Understanding the relative importance of these waves as well as where and under what conditions they are generated is vital to predicting radiation belt dynamics. Although the size of the solar wind compression on 9 January 2014 event discussed here was modest, it has given us an opportunity to observe clearly how a magnetospheric compression can lead to the generation of EMIC, chorus, and hiss waves. The ICME generated shock encountered the Earth's magnetosphere on 9 January 2014 at ~20:11 UT, and the Van Allen Probes observe the coincident excitation of EMIC and Chorus waves outside the plasmasphere, and hiss weaves inside the plasmasphere. As the shock encountered the magnetosphere, an electric field impulse was observed to generate an increase in temperature anisotropy for both ions and electrons. This increased temperature anisotropy led to increased wave growth on both the ion and electron cyclotron branches. The simultaneous generation of multiple types of waves may lead to significant impacts on the acceleration and loss of radiation belt electrons, especially during geomagnetic compressions observed during the substorms, and the storm sudden commencement and main phases of geomagnetic storms, as well as during quiet time sudden impulse events. For example, the excitation of both EMIC and chorus waves at the same place, and at the same time, may complicate studies seeking a causal connection between specific individual plasma wave bursts and observations of particle precipitation into the atmosphere. During this relatively small event BARREL had three payloads in conjunction with the Van

  16. Reestablecimiento de Choromytilus chorus (Molina, 1782) (Bivalvia: Mytilidae) en el norte de Chile Reestablishment of Choromytilus chorus (Molina, 1782) (Bivalvia: Mytilidae) in northern Chile

    OpenAIRE

    Miguel Avendaño; Marcela Cantillánez

    2011-01-01

    Hasta fines del siglo pasado no existían registros de la presencia de Choromytilus chorus al norte de los 23°S, pese a antecedentes que señalaban su existencia en épocas pasadas. Ciertos cambios relacionados con las masas de agua costeras de esta zona, habrían generado la ausencia o escasez que presentaba el entorno costero actual. Sin embargo, hace una década atrás, su presencia en el norte de Chile, comienza a tener connotación pesquera. En el presente trabajo se confirma su reestablecimien...

  17. Reestablecimiento de Choromytilus chorus (Molina, 1782 (Bivalvia: Mytilidae en el norte de Chile Reestablishment of Choromytilus chorus (Molina, 1782 (Bivalvia: Mytilidae in northern Chile

    Directory of Open Access Journals (Sweden)

    Miguel Avendaño

    2011-07-01

    Full Text Available Hasta fines del siglo pasado no existían registros de la presencia de Choromytilus chorus al norte de los 23°S, pese a antecedentes que señalaban su existencia en épocas pasadas. Ciertos cambios relacionados con las masas de agua costeras de esta zona, habrían generado la ausencia o escasez que presentaba el entorno costero actual. Sin embargo, hace una década atrás, su presencia en el norte de Chile, comienza a tener connotación pesquera. En el presente trabajo se confirma su reestablecimiento en las regiones de Antofagasta y Tarapacá, mediante prospecciones realizadas en seis lugares donde se registró su presencia, así como mediante la captación de semilla en colectores suspendidos. Se indica interacción con Aulacomya ater, a la cual ha desplazado a estratos más profundos, mientras que su reestablecimiento, iniciado en las regiones de Atacama y Antofagasta, y que se amplió posteriormente a la región de Tarapacá; permite postular la hipótesis que la dinámica de estos bancos, respondería a una estructura de metapoblación, dado el sistema de corrientes y vientos que predominan en la zona norte, permitiendo la advección larval de poblaciones existentes en la región de Coquimbo.Despite indications of its presence in past ages, until the end of the last century, no records showed Choromytilus chorus north of 23°S. Certain changes related to coastal water masses in the zone could be responsible for the present lack or scarcity of this species in the coastal area. However, a decade ago, this species appeared in northern Chile in the context of fisheries. This study confirms the re-establishment of C. chorus in the Antofagasta and Tarapaca regions through surveys at six sites where the species had been registered and spat collection using suspended collectors. This species has interacted with Aulacomya ater, displacing it towards deeper habitats. The re-establishment of C. chorus began in the Atacama and Antofagasta regions and

  18. Pitch Angle Distribution Evolution of Energetic Electrons by Whistler-Mode Chorus

    Institute of Scientific and Technical Information of China (English)

    ZHENG Hui-Nan; SU Zhen-Peng; XIONG Ming

    2008-01-01

    We develop a two-dimensional momentum and pitch angle code to solve the typical Fokker-Planck equation which governs wave-particle interaction in space plasmas. We carry out detailed calculations of momentum and pitch angle diffusion coefficients, and temporal evolution of pitch angle distribution for a band of chorus frequency distributed over a standard Gaussian spectrum particularly in the heart of the Earth's radiation belt L = 4.5,where peaks of the electron phase space density are observed. We find that the Whistler-mode chorus can produce significant acceleration of electrons at large pitch angles, and can enhance the phase space density for energies of 0.5~1 MeV by a factor of 10 or above after about 24h. This result can account for observation of significant enhancement in flux of energetic electrons during the recovery phase of a geomagnetic storm.

  19. CHORUS OF MUSHROOMS (CORO DE SETAS) DE HIROMI GOTO: MIGRACIÓN, IDENTIDAD E HISTORIAS.

    OpenAIRE

    Irene, Starace

    2010-01-01

    A partir de los años Setenta del siglo pasado, en Canadá empezó a ser publicada una producción de notable calidad por autores de origen japonés. La novela que voy a analizar, Chorus of mushrooms, de Hiromi Goto, publicada en 1994, es una de estas obras y explora los temas de la migración, del idioma, de las historias como medio para encontrar una identidad.

  20. Self-to-other ratios measured in an opera chorus in performance

    Science.gov (United States)

    Ternström, Sten; Cabrera, Densil; Davis, Pamela

    2005-12-01

    Four volunteer members of the chorus of Opera Australia, representing four different voice categories, wore binaural pairs of wireless microphones during a penultimate dress rehearsal on the Opera Theater stage of the Sydney Opera House. From the recordings, data were obtained on sound levels and on the self-to-other ratios (SORs). The sound levels were comparable to those found in loud music in chamber choir performance. The average SOR ranged from +10 to +15 dB. Compared to chamber choirs in other types of room, the SOR values were high. On a separate occasion, the stage support parameters ST1 (early reflections) and ST2 (late reflections) were measured over the whole stage area. ST1 was about -16 dB, which is typical for opera stages, and -20 dB for ST2, which is unusually low. It is concluded that the SOR in the opera chorus depends mostly on choir formation, which is highly variable, and that an opera chorus artist generally can hear his or her own voice very well, but little of the others and of the orchestra. This was confirmed by informal listening to the recordings.

  1. Nonlinear dynamics of electrons interacting with oblique whistler mode chorus in the magnetosphere

    Science.gov (United States)

    Hsieh, Yi-Kai; Omura, Yoshiharu

    2017-01-01

    We perform test particle simulations for relativistic electrons interacting with a whistler mode chorus packet propagating at oblique angles. By confirming that the energy transport of oblique lower band chorus is nearly along the ambient magnetic field, we apply the gyroaveraging method in calculating equations of motion of electrons. We trace evolution of a delta function of relativistic electrons in a phase space of kinetic energy and equatorial pitch angle and obtain numerical Green's functions of the chorus wave-particle interactions. Examining the Green's functions in a wide range of kinetic energies, we find that Landau resonance can accelerate MeV electrons efficiently and that higher nth resonances such as n =- 1 and n = 2 also contribute to acceleration of electrons at high equatorial pitch angles (˜70°) and high energies (˜2 MeV). We investigate the rate of energy gain of the cyclotron resonance acceleration and the Landau resonance acceleration and find that the perpendicular component of wave electric field dominates both accelerations for MeV electrons. Furthermore, the proximity between the parallel components of Vp and Vg of oblique whistler mode waves and the nonlinear trapping condition make the interaction time of Landau resonance much longer than that of n = 1 cyclotron resonance, resulting in efficient acceleration of MeV electrons.

  2. Descriptions of three new species of Mitridae (Mollusca: Gastropoda) from South China Sea

    Institute of Scientific and Technical Information of China (English)

    LI Baoquan; ZHANG Suping; LI Xinzheng

    2005-01-01

    Three new species of Family Mitridae (Mollusca: Gastropoda) from the South China Sea are described in the present paper. They are Ziba aglais sp. nov. B. LI & S. ZHANG, Neocancilla daidaleosa sp.nov. B. LI & X. LI, and Mitra holkosa sp. nov. B. LI. Their systematic positions are also discussed.

  3. Ultralong Cycle Life Achieved by a Natural Plant: Miscanthus × giganteus for Lithium Oxygen Batteries.

    Science.gov (United States)

    Li, Shu; Bi, Xuanxuan; Tao, Ran; Wang, Qingzhen; Yao, Ying; Wu, Feng; Zhang, Cunzhong

    2017-02-08

    Large energy-storage systems and electric vehicles require energy devices with high power and high energy density. Lithium oxygen (Li-O2) batteries could achieve high energy density, but they are still facing problems such as low practical capacity and poor cyclability. Here, we prepare activated carbons (MGACs) based on the natural plant Miscanthus × giganteus (MG) through slow pyrolysis. It possesses a large surface area, plenty of active sites, and high porosity, which are beneficial to the utilization of oxygen electrode in Li-O2 batteries. The MGACs-based oxygen electrode delivers a high specific capacity of 9400 mAh/g at 0.02 mA/cm(2), and long cycle life of 601 cycles (with a cutoff capacity of 500 mAh/g) and 295 cycles (with a cutoff capacity of 1000 mAh/g) at 0.2 mA/cm(2), respectively. Additionally, the material exhibits high rate capability and high reversibility, which is a promising candidate for the application in Li-O2 batteries.

  4. Environmental hazards related to Miscanthus x giganteus cultivation on heavy metal contaminated soil

    Directory of Open Access Journals (Sweden)

    Pogrzeba M.

    2013-04-01

    Full Text Available According to recent estimates reaching the target of a 20% share of renewable energy sources (RES in the final energy balance in Poland by 2020 will result in the demand for more than 8 million tons of biomass, which, in turn, will entail the necessity of creating large-scale energy crop plantations. According to EU assumptions the most effective way to produce biomass for energy purposes is cultivation of energy crops in agricultural areas. It is particularly vital for Poland, because these areas constitute a relatively large part of the country (59%, 76% of them being used as farmlands. In Silesia, the most industrialized region of the country, 5-10% of agricultural soils are contaminated with cadmium, lead and zinc. The main objective of the presented study was to estimate the accumulation of heavy metals in the tissues of Miscanthus x giganteus grown on contaminated soils and calculate concentrations of Pb, Cd and Zn in crops. It was shown that the large intake of heavy metals by that species could cause high emissions of pollutants into the atmosphere during its improper combustion. As a side effect, winter harvesting led to the loss of even 30% of biomass. Plant residues (leaves can be the source of pollution after decomposing and releasing metals back into the soil. Moreover, miscanthus leaves can be transferred by wind to the surrounding areas. It is very likely that ash coming from the combustion of contaminated biomass cannot be used as a fertilizer.

  5. Gasification of torrefied Miscanthus × giganteus in an air-blown bubbling fluidized bed gasifier.

    Science.gov (United States)

    Xue, G; Kwapinska, M; Horvat, A; Kwapinski, W; Rabou, L P L M; Dooley, S; Czajka, K M; Leahy, J J

    2014-05-01

    Torrefaction is suggested to be an effective method to improve the fuel properties of biomass and gasification of torrefied biomass should provide a higher quality product gas than that from unprocessed biomass. In this study, both raw and torrefied Miscanthus × giganteus (M×G) were gasified in an air-blown bubbling fluidized bed (BFB) gasifier using olivine as the bed material. The effects of equivalence ratio (ER) (0.18-0.32) and bed temperature (660-850°C) on the gasification performance were investigated. The results obtained suggest the optimum gasification conditions for the torrefied M × G are ER 0.21 and 800°C. The product gas from these process conditions had a higher heating value (HHV) of 6.70 MJ/m(3), gas yield 2m(3)/kg biomass (H2 8.6%, CO 16.4% and CH4 4.4%) and cold gas efficiency 62.7%. The comparison between raw and torrefied M × G indicates that the torrefied M × G is more suitable BFB gasification.

  6. Cutaneous and diphtheritic avian poxvirus infection in a nestling Southern Giant Petrel (Macronectes giganteus) from Antarctica

    Science.gov (United States)

    Shearn-Bochsler, Valerie; Green, David Earl; Converse, K.A.; Docherty, D.E.; Thiel, T.; Geisz, H.N.; Fraser, William R.; Patterson-Fraser, Donna L.

    2008-01-01

    The Southern giant petrel (Macronectes giganteus) is declining over much of its range and currently is listed as vulnerable to extinction by the International Union for the Conservation of Nature (IUCN). Island-specific breeding colonies near Palmer Station, Antarctica, have been monitored for over 30 years, and because this population continues to increase, it is critically important to conservation. In austral summer 2004, six diseased giant petrel chicks were observed in four of these colonies. Diseased chicks were 6a??9 weeks old and had multiple proliferative nodules on their bills and skin. One severely affected chick was found dead on the nest and was salvaged for necropsy. Histopathological examination of nodules from the dead chick revealed epithelial cell hyperplasia and hypertrophy with numerous eosinophilic intracytoplasmic inclusions (B??llinger bodies). A poxvirus was isolated from multiple nodules. Poxviral infection has not been reported in this species, and the reason for its emergence and its potential impact on the population are not yet known.

  7. Catalytic pyrolysis of miscanthus × giganteus in a spouted bed reactor.

    Science.gov (United States)

    Du, Shoucheng; Sun, Yijia; Gamliel, David P; Valla, Julia A; Bollas, George M

    2014-10-01

    A conical spouted bed reactor was designed and tested for fast catalytic pyrolysis of miscanthus × giganteus over Zeolite Socony Mobil-5 (ZSM-5) catalyst, in the temperature range of 400-600 °C and catalyst to biomass ratios 1:1-5:1. The effect of operating conditions on the lumped product distribution, bio-oil selectivity and gas composition was investigated. In particular, it was shown that higher temperature favors the production of gas and bio-oil aromatics and results in lower solid and liquid yields. Higher catalyst to biomass ratios increased the gas yield, at the expense of liquid and solid products, while enhancing aromatic selectivity. The separate catalytic effects of ZSM-5 catalyst and its Al2O3 support were studied. The support contributes to increased coke/char formation, due to the uncontrolled spatial distribution and activity of its alumina sites. The presence of ZSM-5 zeolite in the catalyst enhanced the production of aromatics due to its proper pore size distribution and activity.

  8. Profiling the Chemical Composition and Growth Strain of Giant Bamboo (Dendrocalamus giganteus Munro

    Directory of Open Access Journals (Sweden)

    Hui-Ting Chang

    2015-01-01

    Full Text Available The chemical composition of the wax layer and green epidermis at the surface of giant bamboo (Dendrocalamus giganteus Munro culms were conveniently analyzed through the diffuse reflectance infrared Fourier transform (DRIFT with Si-Carb sampling technique. Results from the radial lignin content profiling of giant bamboo showed that the lignin content in the middle layer was lower than the layers either from the inner or outer culms. As for the longitudinal depth profiling, the lignin contents of bamboo culms increased gradually from the top toward base portion. The distribution of growth strains in the radial direction of giant bamboo culm was investigated by the kerf method with strain gauges. The longitudinal tensile strains in various positions of giant bamboo culm were found to decrease in the order of the middle layer, the outer layer, and the inner layer. The tensile strains of different layers in the radial direction of giant bamboo culm correlate with their lignin content. The highest tensile strain on the middle layer of the bamboo culm was associated with the lowest lignin content. These results provided experimental evidence in the relationship between longitudinal tensile strain and lignin content of bamboo culm.

  9. Spatio-temporal variation of core and satellite arbuscular mycorrhizal fungus communities in Miscanthus giganteus

    Directory of Open Access Journals (Sweden)

    Christopher James Barnes

    2016-08-01

    Full Text Available Arbuscular mycorrhizal fungi (AMF are a group of obligate plant symbionts which can promote plant nutrition. AMF communities are diverse, but the factors which control their assembly in space and time remain unclear. In this study, the contributions of geographical distance, environmental heterogeneity and time to shaping AMF communities associated with Miscanthus giganteus were determined over a 13 month period. In particular, the community was partitioned into core (abundant and persistent taxa and satellite (taxa with low abundance and persistence constituents and the drivers of community assembly for each determined. We show that AMF richness and community composition changed over time associated with fluctuation within both the core and satellite communities. The degree to which AMF community variation was explained by soil properties was consistently higher in the core community than the combined and satellite communities, suggesting that the satellite community had considerable stochasticity associated with it. We suggest that the partitioning of communities into their core and satellite constituents could be employed to enhance the variation explained within microbial community analyses.

  10. Spatio-Temporal Variation of Core and Satellite Arbuscular Mycorrhizal Fungus Communities in Miscanthus giganteus

    Science.gov (United States)

    Barnes, Christopher J.; Burns, Caitlin A.; van der Gast, Christopher J.; McNamara, Niall P.; Bending, Gary D.

    2016-01-01

    Arbuscular mycorrhizal fungi (AMF) are a group of obligate plant symbionts which can promote plant nutrition. AMF communities are diverse, but the factors which control their assembly in space and time remain unclear. In this study, the contributions of geographical distance, environmental heterogeneity and time in shaping AMF communities associated with Miscanthus giganteus (a perennial grass originating from south-east Asia) were determined over a 13 months period. In particular, the community was partitioned into core (abundant and persistent taxa) and satellite (taxa with low abundance and persistence) constituents and the drivers of community assembly for each determined. β-diversity was exceptionally low across the 140 m line transects, and there was limited evidence of geographical scaling effects on the composition of the core, satellite or combined communities. However, AMF richness and community composition changed over time associated with fluctuation within both the core and satellite communities. The degree to which AMF community variation was explained by soil properties was consistently higher in the core community than the combined and satellite communities, suggesting that the satellite community had considerable stochasticity associated with it. We suggest that the partitioning of communities into their core and satellite constituents could be employed to enhance the variation explained within microbial community analyses. PMID:27597844

  11. Whistler anisotropy instabilities as the source of banded chorus: Van Allen Probes observations and particle-in-cell simulations.

    Science.gov (United States)

    Fu, Xiangrong; Cowee, Misa M; Friedel, Reinhard H; Funsten, Herbert O; Gary, S Peter; Hospodarsky, George B; Kletzing, Craig; Kurth, William; Larsen, Brian A; Liu, Kaijun; MacDonald, Elizabeth A; Min, Kyungguk; Reeves, Geoffrey D; Skoug, Ruth M; Winske, Dan

    2014-10-01

    Magnetospheric banded chorus is enhanced whistler waves with frequencies ωr particle-in-cell simulations in a magnetized, homogeneous, collisionless plasma to test the hypothesis that banded chorus is due to local linear growth of two branches of the whistler anisotropy instability excited by two distinct, anisotropic electron components of significantly different temperatures. The electron densities and temperatures are derived from Helium, Oxygen, Proton, and Electron instrument measurements on the Van Allen Probes A satellite during a banded chorus event on 1 November 2012. The observations are consistent with a three-component electron model consisting of a cold (a few tens of eV) population, a warm (a few hundred eV) anisotropic population, and a hot (a few keV) anisotropic population. The simulations use plasma and field parameters as measured from the satellite during this event except for two numbers: the anisotropies of the warm and the hot electron components are enhanced over the measured values in order to obtain relatively rapid instability growth. The simulations show that the warm component drives the quasi-electrostatic upper band chorus and that the hot component drives the electromagnetic lower band chorus; the gap at ∼Ω e /2 is a natural consequence of the growth of two whistler modes with different properties.

  12. Whistler anisotropy instabilities as the source of banded chorus: Van Allen Probes observations and particle-in-cell simulations

    Science.gov (United States)

    Fu, Xiangrong; Cowee, Misa M.; Friedel, Reinhard H.; Funsten, Herbert O.; Gary, S. Peter; Hospodarsky, George B.; Kletzing, Craig; Kurth, William; Larsen, Brian A.; Liu, Kaijun; MacDonald, Elizabeth A.; Min, Kyungguk; Reeves, Geoffrey D.; Skoug, Ruth M.; Winske, Dan

    2014-10-01

    Magnetospheric banded chorus is enhanced whistler waves with frequencies ωrcell simulations in a magnetized, homogeneous, collisionless plasma to test the hypothesis that banded chorus is due to local linear growth of two branches of the whistler anisotropy instability excited by two distinct, anisotropic electron components of significantly different temperatures. The electron densities and temperatures are derived from Helium, Oxygen, Proton, and Electron instrument measurements on the Van Allen Probes A satellite during a banded chorus event on 1 November 2012. The observations are consistent with a three-component electron model consisting of a cold (a few tens of eV) population, a warm (a few hundred eV) anisotropic population, and a hot (a few keV) anisotropic population. The simulations use plasma and field parameters as measured from the satellite during this event except for two numbers: the anisotropies of the warm and the hot electron components are enhanced over the measured values in order to obtain relatively rapid instability growth. The simulations show that the warm component drives the quasi-electrostatic upper band chorus and that the hot component drives the electromagnetic lower band chorus; the gap at ˜Ωe/2 is a natural consequence of the growth of two whistler modes with different properties.

  13. Observation of chorus waves by the Van Allen Probes: Dependence on solar wind parameters and scale size

    Science.gov (United States)

    Aryan, Homayon; Sibeck, David; Balikhin, Michael; Agapitov, Oleksiy; Kletzing, Craig

    2016-08-01

    Highly energetic electrons in the Earth's Van Allen radiation belts can cause serious damage to spacecraft electronic systems and affect the atmospheric composition if they precipitate into the upper atmosphere. Whistler mode chorus waves have attracted significant attention in recent decades for their crucial role in the acceleration and loss of energetic electrons that ultimately change the dynamics of the radiation belts. The distribution of these waves in the inner magnetosphere is commonly presented as a function of geomagnetic activity. However, geomagnetic indices are nonspecific parameters that are compiled from imperfectly covered ground based measurements. The present study uses wave data from the two Van Allen Probes to present the distribution of lower band chorus waves not only as functions of single geomagnetic index and solar wind parameters but also as functions of combined parameters. Also the current study takes advantage of the unique equatorial orbit of the Van Allen Probes to estimate the average scale size of chorus wave packets, during close separations between the two spacecraft, as a function of radial distance, magnetic latitude, and geomagnetic activity, respectively. Results show that the average scale size of chorus wave packets is approximately 1300-2300 km. The results also show that the inclusion of combined parameters can provide better representation of the chorus wave distributions in the inner magnetosphere and therefore can further improve our knowledge of the acceleration and loss of radiation belt electrons.

  14. A direct link between chorus emissions and pulsating aurora on timescales from milliseconds to minutes: A case study at subauroral latitudes

    Science.gov (United States)

    Ozaki, Mitsunori; Yagitani, Satoshi; Sawai, Kaoru; Shiokawa, Kazuo; Miyoshi, Yoshizumi; Kataoka, Ryuho; Ieda, Akimasa; Ebihara, Yusuke; Connors, Martin; Schofield, Ian; Katoh, Yuto; Otsuka, Yuichi; Sunagawa, Naoki; Jordanova, Vania K.

    2015-11-01

    A correlation was observed between chorus emissions and pulsating aurora (PA) from observations at Athabasca (L≈4.3) in Canada at 9:00-9:20 UT on 7 February 2013, using an electron multiplying charge-coupled device camera and a VLF loop antenna with sampling rates of 110 Hz and 100 kHz, respectively. Pulsating aurora having a quasiperiodic variation in luminosity and a few hertz modulation was observed together with chorus emissions consisting of a group of successive rising-tone elements. The repetition period and modulation frequency of the PA are in good agreement with those of the modulated chorus. After 9:11 UT, the temporal features of the aurora became aperiodic PA of indistinct modulation. Simultaneously, the rising-tone chorus turned into chorus emissions consisting of numerous rising-tone elements. The equatorial geomagnetic field inhomogeneity calculated using the Tsyganenko 2002 model shows a decreasing trend during the period. This result is consistent with nonlinear wave growth theory having a small geomagnetic field inhomogeneity, which contributes to a decrease in the threshold amplitude to trigger discrete chorus elements. These observations show a close connection between chorus emissions and PA on timescales from milliseconds for generation of discrete chorus elements on the microphysics of wave-particle interaction to minutes for the variations of the geomagnetic field inhomogeneity related with the substorm activity.

  15. Radial variation of whistler-mode chorus: first results from the STAFF/DWP instrument on board the Double Star TC-1 spacecraft

    Directory of Open Access Journals (Sweden)

    O. Santolík

    2005-11-01

    Full Text Available We use the first measurements of the STAFF/DWP instrument on the Double Star TC-1 spacecraft to investigate whistler-mode chorus. We present initial results of a systematic study on radial variation of dawn chorus. The chorus events show an increased intensity at L parameter above 6. This is important for the possible explanation of intensifications of chorus, which were previously observed closer to the Earth at higher latitudes. Our results also indicate that the upper band of chorus at frequencies above one-half of the electron cyclotron frequency disappears for L above 8. The lower band of chorus is observed at frequencies below 0.4 of the electron cyclotron frequency up to L of 11-12. The maxima of the chorus power spectra are found at slightly lower frequencies compared to previous studies. We do not observe any distinct evolution of the position of the chorus frequency band as a function of L. More data of the TC-1 spacecraft are needed to verify these initial results and to increase the MLT coverage.

  16. Van Allen Probes observations of prompt MeV radiation belt electron acceleration in nonlinear interactions with VLF chorus

    Science.gov (United States)

    Foster, J. C.; Erickson, P. J.; Omura, Y.; Baker, D. N.; Kletzing, C. A.; Claudepierre, S. G.

    2017-01-01

    Prompt recovery of MeV (millions of electron Volts) electron populations in the poststorm core of the outer terrestrial radiation belt involves local acceleration of a seed population of energetic electrons in interactions with VLF chorus waves. Electron interactions during the generation of VLF rising tones are strongly nonlinear, such that a fraction of the relativistic electrons at resonant energies are trapped by waves, leading to significant nonadiabatic energy exchange. Through detailed examination of VLF chorus and electron fluxes observed by Van Allen Probes, we investigate the efficiency of nonlinear processes for acceleration of electrons to MeV energies. We find through subpacket analysis of chorus waveforms that electrons with initial energy of hundreds of keV to 3 MeV can be accelerated by 50 keV-200 keV in resonant interactions with a single VLF rising tone on a time scale of 10-100 ms.

  17. Equatorial electron loss by double resonance with oblique and parallel intense chorus waves

    Science.gov (United States)

    Mourenas, D.; Artemyev, A. V.; Agapitov, O. V.; Mozer, F. S.; Krasnoselskikh, V. V.

    2016-05-01

    Puzzling satellite observations of butterfly pitch angle distributions and rapid dropouts of 30-150 keV electrons are widespread in the Earth's radiation belts. Several mechanisms have been proposed to explain these observations, such as enhanced outward radial diffusion combined with magnetopause shadowing or scattering by intense magnetosonic waves, but their effectiveness is mainly limited to storm times. Moreover, the scattering of 30-150 keV electrons via cyclotron resonance with intense parallel chorus waves should be limited to particles with equatorial pitch angle smaller than 70°-75°, leaving unaffected a large portion of the population. In this paper, we investigate the possible effects of oblique whistler mode waves, noting, in particular, that Landau resonance with very oblique waves can occur up to ˜89°. We demonstrate that such very oblique chorus waves with realistic amplitudes can very efficiently nonlinearly transport nearly equatorially mirroring electrons toward smaller pitch angles where nonlinear scattering (phase bunching) via cyclotron resonance with quasi-parallel waves can take over and quickly send them to much lower pitch angles <40°. The proposed double resonance mechanism could therefore explain the formation of butterfly pitch angle distributions as well as contribute to some fast dropouts of 30-150 keV electrons occurring during moderate geomagnetic disturbances at L = 4-6. Since 30-150 keV electrons represent a seed population for a further acceleration to relativistic energies by intense parallel chorus waves during storms or substorms, the proposed mechanism may have important consequences on the dynamics of 100 keV to MeV electron fluxes in the radiation belts.

  18. Evidence for acceleration of outer zone electrons to relativistic energies by whistler mode chorus

    Directory of Open Access Journals (Sweden)

    N. P. Meredith

    Full Text Available We use plasma wave and electron data from the Combined Release and Radiation Effects Satellite (CRRES to investigate the viability of a local stochastic electron acceleration mechanism to relativistic energies driven by gyroresonant interactions with whistler mode chorus. In particular, we examine the temporal evolution of the spectral response of the electrons and the waves during the 9 October 1990 geomagnetic storm. The observed hardening of the electron energy spectra over about 3 days in the recovery phase is coincident with prolonged substorm activity, as monitored by the AE index and enhanced levels of whistler mode chorus waves. The observed spectral hardening is observed to take place over a range of energies appropriate to the resonant energies associated with Doppler-shifted cyclotron resonance, as supported by the construction of realistic resonance curves and resonant diffusion surfaces. Furthermore, we show that the observed spectral hardening is not consistent with energy-independent radial diffusion models. These results provide strong circumstantial evidence for a local stochastic acceleration mechanism, involving the energisation of a seed population of electrons with energies of the order of a few hundred keV to relativistic energies, driven by wave-particle interactions involving whistler mode chorus. The results suggest that this mechanism contributes to the reformation of the relativistic outer zone population during geomagnetic storms, and is most effective when the recovery phase is characterised by prolonged substorm activity. An additional significant result of this paper is that we demonstrate that the lower energy part of the storm-time electron distribution is in steady-state balance, in accordance with the Kennel and Petschek (1966 theory of limited stably-trapped particle fluxes.

    Key words. Magnetospheric physics (storms and substorms, energetic particles, trapped – Space plasma physics (wave

  19. Propagation of whistler-mode chorus to low altitudes: divergent ray trajectories and ground accessibility

    Directory of Open Access Journals (Sweden)

    J. Chum

    2005-12-01

    Full Text Available We investigate the ray trajectories of nonductedly propagating lower-band chorus waves with respect to their initial angle θ0, between the wave vector and ambient magnetic field. Although we consider a wide range of initial angles θ0, in order to be consistent with recent satellite observations, we pay special attention to the intervals of initial angles θ0, for which the waves propagate along the field lines in the source region, i.e. we mainly focus on waves generated with &theta0 within an interval close to 0° and on waves generated within an interval close to the Gendrin angle. We demonstrate that the ray trajectories of waves generated within an interval close to the Gendrin angle with a wave vector directed towards the lower L-shells (to the Earth significantly diverge at the frequencies typical for the lower-band chorus. Some of these diverging trajectories reach the topside ionosphere having θ close to 0°; thus, a part of the energy may leak to the ground at higher altitudes where the field lines have a nearly vertical direction. The waves generated with different initial angles are reflected. A small variation of the initial wave normal angle thus very dramatically changes the behaviour of the resulting ray. Although our approach is rather theoretical, based on the ray tracing simulation, we show that the initial angle θ0 of the waves reaching the ionosphere (possibly ground is surprisingly close - differs just by several degrees from the initial angles which fits the observation of magnetospherically reflected chorus revealed by CLUSTER satellites. We also mention observations of diverging trajectories on low altitude satellites.

  20. Organic pollutant burden of the giant mussels Choromytilus chorus from the south-central Chilean coast.

    Science.gov (United States)

    Toro, Beatriz; Palma-Fleming, Hernán; Navarro, Jorge M

    2004-04-01

    A comparative quantitative analysis was made on the contents of organochlorines (OCh) and polycyclic aromatic hydrocarbons (PAH) in tissues of the giant mussel Choromytilus chorus from three bays in south-central Chile exposed to various degrees of pollutant input. Mussels from the three bays contained levels of OCh near the detection limits of method, with a tendency to be slightly higher in the polluted bay (San Vicente) than in the other bays (Corral and Yaldad). PAH levels and types in Corral and Yaldad were well below of carcinogenicity permitted in mussels for human consumption.

  1. Reestablecimiento de Choromytilus chorus (Molina, 1782) (Bivalvia: Mytilidae) en el norte de Chile

    OpenAIRE

    Avendaño,Miguel; Cantillánez,Marcela

    2011-01-01

    Hasta fines del siglo pasado no existían registros de la presencia de Choromytilus chorus al norte de los 23°S, pese a antecedentes que señalaban su existencia en épocas pasadas. Ciertos cambios relacionados con las masas de agua costeras de esta zona, habrían generado la ausencia o escasez que presentaba el entorno costero actual. Sin embargo, hace una década atrás, su presencia en el norte de Chile, comienza a tener connotación pesquera. En el presente trabajo se confirma su reestablecimien...

  2. Characterization of Miscanthus giganteus lignin isolated by ethanol organosolv process under reflux condition.

    Science.gov (United States)

    Bauer, Stefan; Sorek, Hagit; Mitchell, Valerie D; Ibáñez, Ana B; Wemmer, David E

    2012-08-22

    Miscanthus giganteus lignin was extracted by an organosolv process under reflux conditions (4 h) with varying concentrations of ethanol (65%, 75%, 85%, 95%) and 0.2 M hydrochloric acid as catalyst. The resulting lignin was extensively characterized by size exclusion chromatography (SEC), Fourier-transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC/MS), two-dimensional nuclear magnetic resonance spectroscopy (2D-NMR), and chemical analysis (residual sugars, Klason lignin, ash). The predominant linkage units present were β-O-4' (82-84%), resinol (6-7%), and phenylcoumaran (10-11%). The 65% ethanol solvent system gave the lowest lignin yield (14% of starting biomass) compared to 29-32% of the other systems. Increasing ethanol concentration resulted in decreasing carbohydrate content of the lignins (3.6-1.1%), a higher solubility in tetrahydrofuran (THF), a slight reduction of the molecular weight (M(w) 2.72-2.25 KDa), an increasing α-ethoxylation, and an increase in ethoxylated phenylpropenoic compounds (p-coumaric and ferulic acid), but the S/G ratio of the monolignols (0.63, GC/MS) and Klason lignin content (86-88%) were unaffected. An extraction method for these ethyl-esterified phenylpropenoids and smaller molecular weight lignin compounds was developed. The effect of reaction time (2, 4, and 8 h) was investigated for the 95% ethanol solvent system. Besides increased lignin yield (13-43%), a slight increase in M(w) (2.21-2.38 kDa) and S/G ratio (0.53-0.68, GC-MS) was observed. Consecutive extractions suggested that these changes were not from lignin modifications (e.g., condensations) but rather from extraction of lignin of different composition. The results were compared to similar solvent systems with 95% acetone and 95% dioxane.

  3. Effect of Steam Explosion Pretreatment on the Specific Methane Yield of Miscanthus x giganteus

    Directory of Open Access Journals (Sweden)

    Franz Theuretzbacher

    2014-03-01

    Full Text Available A highly promising energy crop for biogas production can be Miscanthus x giganteus. It has multiple advantages, which include low soil requirements and the existence of genotypes adapted to dry conditions in comparison to other energy crops. Miscanthus cannot be used in the biogas plant without a pretreatment due to the recalcitrant nature of lignocelluloses. One of the most efficient pretreatment methods for lignocellulosic biomass is steam explosion. This includes heating the biomass at high temperature values, followed by mechanical disruption of the biomass fibres by a rapid pressure drop. The objective of this study is to analyse the effect of the steam explosion pretreatment on the specific biogas and methane production of miscanthus. In addition methane hectare yields are calculated and compared to those of maize. Steam explosion pretreatment was carried out in a laboratory scale facility in Ĺs, Norway. The miscanthus was mixed with water and heated up to the desired temperature. After a defined pretreatment time the pressure in the reaction vessel was reduced rapidly, which caused the liquid water to vaporize immediately. The material was cooled down in a flushing tank and was then stored at 5°C until further analytical procedures. Pretreatment temperatures were 190°C and 210°C; holding times were 5, 10 and 15 minutes. Determination of the specific methane yield was done in triplicate using batch tests according to VDI 4630. The material was inoculated with the liquid fermentation residue of a biogas plant. The produced gas was collected in eudiometers and then analysed for the CH4 and CO2 content.

  4. Effect of Steam Explosion Pretreatment on the Specific Methane Yield of Miscanthus x giganteus

    Directory of Open Access Journals (Sweden)

    Franz Theuretzbacher

    2014-05-01

    Full Text Available A highly promising energy crop for biogas production can be Miscanthus x giganteus. It has multiple advantages, which include low soil requirements and the existence of genotypes adapted to dry conditions in comparison to other energy crops. Miscanthus cannot be used in the biogas plant without a pretreatment due to the recalcitrant nature of lignocelluloses. One of the most efficient pretreatment methods for lignocellulosic biomass is steam explosion. This includes heating the biomass at high temperature values, followed by mechanical disruption of the biomass fibres by a rapid pressure drop. The objective of this study is to analyse the effect of the steam explosion pretreatment on the specific biogas and methane production of miscanthus. In addition methane hectare yields are calculated and compared to those of maize. Steam explosion pretreatment was carried out in a laboratory scale facility in Ĺs, Norway. The miscanthus was mixed with water and heated up to the desired temperature. After a defined pretreatment time the pressure in the reaction vessel was reduced rapidly, which caused the liquid water to vaporize immediately. The material was cooled down in a flushing tank and was then stored at 5°C until further analytical procedures. Pretreatment temperatures were 190°C and 210°C; holding times were 5, 10 and 15 minutes. Determination of the specific methane yield was done in triplicate using batch tests according to VDI 4630. The material was inoculated with the liquid fermentation residue of a biogas plant. The produced gas was collected in eudiometers and then analysed for the CH4 and CO2 content. 

  5. Evaluation of suitability of Giant Miscanthus (Miscanthus × giganteus Greef et Deu. in phytoextraction of copper and zinc from soil

    Directory of Open Access Journals (Sweden)

    Maciej Bosiacki

    2013-09-01

    Full Text Available The main objective of this study was to determine the suitability of Miscanthus × giganteus to phytoextraction of copper and zinc from soil, as well as evaluation of the tolerance of this species to the increasing concentration of the metals. Potential for phytoextraction of Miscanthus × giganteus had been studied for two years, pot experiment in the plastic greenhouse when they grown in mineral soil (which was slightly loamy sand and soil with raised peat substrate with four levels of copper and zinc: control (native Cu and Zn content, Cu – 80 mg·dm-3, Zn – 300 mg·dm-3 – weak pollution, Cu – 100 mg·dm-3, Zn – 1000 mg·dm-3 – medium pollution, Cu – 500 mg·dm-3, Zn – 3000 mg·dm-3 – strong pollution. Assessing their potential for copper and zinc phytoextraction from the soil, it was found that it is not significant. No hyperaccumulation of heavy metals in the aboveground biomass was found in this study.

  6. Preliminary Results on Growing Second Generation Biofuel Crop Miscanthus X Giganteus at The Polluted Military Site in Ukraine

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    Pidlisnyuk Valentina

    2016-06-01

    Full Text Available The semi-field research on using second-generation biofuel crop Miscanthus x giganteus for restoration of former military site in Kamenetz-Podilsky, Ukraine was carried out during two vegetation seasons. Despite high metal pollution of soil, in particular, by Fe, Mn, Ti, and Zr, no growth inhibition was observed. The concentrations followed pattern soil > roots > stems > leaves. Accumulation of particular metals in roots was different: Fe, Mn and Ti were accumulated rather palpably after the first vegetation season and less tangible after the second one. Cu, Pb and Zn were less accumulative in both vegetation seasons, and for As and Pb the accumulative concentrations were very small. Accumulations in the aboveground parts of the plant in comparison to roots were significantly lower in case of Fe, Ti, Mn, Cu, Zn, Sr and even statistically comparable to zero in case of As, Pb and Zr. Calculated translocation ratio of metals in the plant’s parts preferably indicated lack of metals’ hyper accumulation. Generally, no correlations were observed between concentrations of metals in the soil and in the upper plant’s parts. The research confirmed the ability of Miscanthus x giganteus to grow on the military soils predominantly contaminated by metals.

  7. Diversity of Indo-West Pacific Siphonaria (Mollusca: Gastropoda: Euthyneura).

    Science.gov (United States)

    Dayrat, Benoît; Goulding, Tricia C; White, Tracy R

    2014-03-14

    Species of the limpet genus Siphonaria (Gastropoda: Euthyneura) are commonly found in the rocky intertidal, worldwide, except in the Arctic. In total, 205 species-group names are available and not permanently invalid. However, estimating the actual species diversity of Siphonaria has remained challenging, mainly because past authors have interpreted differently the variation of shell characters, resulting in different taxonomic accounts. Species diversity of Siphonaria is evaluated for the first time here based on DNA sequence data (three mitochondrial gene fragments: COI, 12S, and 16S) and a large sampling focusing on the tropical and subtropical Indo-West Pacific (from eastern Africa to Hawaii): new sequences are provided for 153 individuals, 123 of which were collected from 93 locations throughout the Indo-West Pacific. In total, 41 species (molecular units) are recognized worldwide (31 from the Indo-West Pacific), all of which are strongly supported. Potential names are discussed for those 41 species, based on traditional taxonomy. The shells of 66 of the individuals from which DNA was extracted are illustrated: intra- and inter-specific variation is documented in detail and discussed in the light of new molecular results. It is shown that many species could hardly be identified based on the shell only, because the variation of shell characters is too high and overlaps between species. Geographically, no species is found across the entire Indo-West Pacific, where quite a few species seem to be endemic to restricted areas. The biogeography of Siphonaria in the Indo-West Pacific is compared to other groups.

  8. Book review: A chorus of cranes: The cranes of North America and the world

    Science.gov (United States)

    Pearse, Aaron T.

    2017-01-01

    Cranes (Gruidae) are widely distributed throughout the world, have lived on Earth for several million years, and currently reside on five continents. Archaeological evidence and historical references suggest that humans have interacted with and been captivated by cranes for many thousands of years (e.g., Leslie 1988, Muellner 1990). A glimpse of our reverence for these birds can be found in A Chorus of Cranes by Paul A. Johnsgard, with photographs by Thomas D. Mangelsen. Many species of cranes are currently identified as threatened or endangered, and their future will likely rest in the hands of humans; this book presents their plight and some of the measures that have been taken to conserve them. Dr. Johnsgard, an emeritus professor at the University of Nebraska-Lincoln, is a prolific writer, having written more than 60 books in ornithology and other topics. This book serves as the latest update of previous efforts concerning crane biology, conservation, and management. A review without making comparisons to his past works is difficult, yet this assessment will primarily focus on the content of the current book, with little reference to past endeavors.A Chorus of Cranes: The Cranes of North America and the World by Paul A. Johnsgard. 2015. University Press of Colorado, Boulder, CO, USA. x + 208 pp., 38 color photographs, 41 figures. ISBN 978-1-60732-436-2. $23.95 (Ebook). ISBN 978-1-60732-436-9.

  9. Relationship between bioenergetics responses and organic pollutants in the giant mussel, Choromytilus chorus (Mollusca: Mytilidae).

    Science.gov (United States)

    Toro, Beatriz; Navarro, Jorge M; Palma-Fleming, Hernán

    2003-05-08

    Samples of Choromytilus chorus (giant mussel) were collected at three sampling stations exposed to different degrees of pollution along the south-central portion of the Chilean coast in spring 1998 and summer 1999. Measurements were carried out on clearance rate, absorption efficiency, and oxygen consumption of the mussels under controlled laboratory conditions, and related to analytical data on organic pollutants in their tissues. Scope for growth (SFG) was employed as a physiological index to evaluate stress produced by pollutants existing at each sampling site. Individuals from San Vicente bay (highly polluted) showed negative SFG values in spring (-4.6 J/h per g) and summer (-3.5 J/h per g). These results indicated severe stress related to the accumulation of toxic compounds in their tissues. Specimens from Corral bay (medium level of pollution) gave a SFG of 15.5 J/h per g in spring and 6.5 J/h per g in summer, while those from Yaldad bay (low pollution) presented an inverse situation was observed with SFG values of 6.2 J/h per g in spring which was lower than the summer value of 25.7 J/h per g. There was a significant negative correlation between the SFG of the different populations of C. chorus and the concentrations of organochlorines (OChs) and polynuclear aromatic hydrocarbons (PAHs) in their tissues.

  10. Dynamic Evolution of Outer Radiation Belt Electrons due to Whistler-Mode Chorus

    Institute of Scientific and Technical Information of China (English)

    SU Zhen-Peng; ZHENG Hui-Nan; XIONG Ming

    2009-01-01

    Following our preceding work,we perform a further study on dynamic evolution of energetic electrons in the outer radiation belt L = 4.5 due to a band of whistler-mode chorus frequency distributed over a standard Gaussian spectrum.We solve the 2D bounce-averaged Fokker-Planck equation by allowing incorporation of cross diffusion rates.Numerical results show that whistler-mode chorus can be effective in acceleration of electrons at large pitch angles,and enhance the phase space density for energies of about 1MeV by a factor of 102 or above in about one day,consistent with observation of significant enhancement in flux of energetic electrons during the recovery phase of a geomagnetic storm.Moreover,neglecting cross diffusion often leads to overestimates of the phase space density evolution at large pitch angle by a factor of 5-10 after one day,with larger errors at smaller pitch angle,suggesting that cross diffusion also plays an important role in wave-particle interaction.

  11. White-throated sparrows alter songs differentially in response to chorusing anurans and other background noise.

    Science.gov (United States)

    Lenske, Ariel K; La, Van T

    2014-06-01

    Animals can use acoustic signals to attract mates and defend territories. As a consequence, background noise that interferes with signal transmission has the potential to reduce fitness, especially in birds that rely on song. While much research on bird song has investigated vocal flexibility in response to urban noise, weather and other birds, the possibility of inter-class acoustic competition from anurans has not been previously studied. Using sound recordings from central Ontario wetlands, we tested if white-throated sparrows (Zonotrichia albicolis) make short-term changes to their singing behaviour in response to chorusing spring peepers (Pseudacris crucifer), as well as to car noise, wind and other bird vocalizations. White-throated sparrow songs that were sung during the spring peeper chorus were shorter with higher minimum frequencies and narrower bandwidths resulting in reduced frequency overlap. Additionally, sparrows were less likely to sing when car noise and the vocalizations of other birds were present. These patterns suggest that birds use multiple adjustment strategies. This is the first report to demonstrate that birds may alter their songs differentially in response to different sources of noise. This article is part of a Special Issue entitled: insert SI title.

  12. Potential growth and biomass productivity of Miscanthus x giganteus as affected by plant density and N-fertilization in central Greece

    NARCIS (Netherlands)

    Danalatos, N.G.; Archontoulis, S.V.; Mitsios, I.

    2007-01-01

    The potential growth and biomass productivity of Miscanthus x giganteus was investigated under constraint-free conditions during two years with appreciable different climatic conditions in central Greece, and under three different plant densities (0.66, 1, 2 pl m(-2)) and two different nitrogen dres

  13. Naididae (Annelida, Oligochaeta associated with Pomacea bridgesii (Reeve (Gastropoda, Ampullaridae Naididae (Annelida: Oligochaeta associados a Pomacea bridgesii (Reeve (Gastropoda, Ampullaridae

    Directory of Open Access Journals (Sweden)

    Guilherme R. Gorni

    2006-12-01

    Full Text Available The family Amplullaridae belongs to this class Gastropoda and is made up of freshwater organisms with a wide geographical distribution in tropical regions. Oligochaeta worms can be found in association with snails of this family, inhabiting the umbilicus of their shells. Due to the lack of information on the ecology of these worms, this work focused on investigating which kind of Oligochaeta species associate with the mollusk Pomacea bridgesii (Reeve, 1856. Samples were collected during winter and spring 2003 and summer 2004. From a total of 209 snails collected, the presence of Oligochaeta worms was observed in only 58 of them (27.75%. In these infected snails, 89 Oligochaeta worms were found, all belonging to the family Naididae. The species Haemonais waldvogeli Bretscher, 1900, Dero (Dero nivea Aiyer, 1929 and Dero (Dero sawayai Marcus, 1943 were the most abundant (43.68%, 12.32% and 10.08%, respectively. Haemonais waldvogeli was found in all of the seasons studied, what demonstrates its affinity for this kind of substrate. The results indicate that several Naididae species find in the umbilicus of these snails's shells (which contains fine detritus a favorable habitat for establishing themselves.A família Ampullaridae, pertencente à classe Gastropoda, é caracterizada por organismos de água doce com ampla distribuição na região tropical. Vermes Oligochaeta associados a esses caracóis podem ser encontrados habitando o umbílico de suas conchas. Devido à carência de informação sobre a ecologia desses vermes, o presente trabalho centrou-se em um levantamento de espécies de Oligochaeta associadas ao molusco Pomacea bridgesii (Reeve, 1856. Em amostragens realizadas no inverno e na primavera de 2003 e no verão de 2004, foram observados 209 caracóis, sendo que somente em 58 deles foi detectada a presença de vermes Oligochaeta, correspondendo a uma incidência de 27,75%. Foram encontrados, no total, 89 oligoquetos, todos da fam

  14. With a little help from DNA barcoding: investigating the diversity of Gastropoda from the Portuguese coast

    OpenAIRE

    2016-01-01

    The Gastropoda is one of the best studied classes of marine invertebrates. Yet, most species have been delimited based on morphology only. The application of DNA barcodes has shown to be greatly useful to help delimiting species. Therefore, sequences of the cytochrome c oxidase I gene from 108 specimens of 34 morpho-species were used to investigate the molecular diversity within the gastropods from the Portuguese coast. To the above dataset, we added available COI-5P sequences of taxonomicall...

  15. Seasonal dynamics of nutrient accumulation and partitioning in the perennial C{sub 4}-grasses Miscanthus x giganteus and Spartina cynosuroides

    Energy Technology Data Exchange (ETDEWEB)

    Beale, C.V. [Writtle College, Chelmsford (United Kingdom)] Long, S.P. [Essex Univ., Colchester (United Kingdom). Dept. of Biological and Chemical Sciences

    1997-12-31

    Seasonal variation in the accumulation and partitioning of nitrogen, phosphorus and potassium was determined in both the above-ground and below-ground dry matter of the potential energy crops Miscanthus x giganteus and Spartina cynosuroides. It is desirable from both economic and environmental perspectives that such crops should exhibit a high nutrient use efficiency and minimal nutrient losses to the environment. The N, P and K concentrations in the above-ground dry matter, at final harvest, were 5.0, 0.6 and 12.0 mg g{sup -1} respectively in M. x giganteus and 3.0, 0.4 and 1.0 mg g{sup -1} in S. cynosurodes. Both species exhibited the high N-use efficiency expected of C{sub 4} plants. Nitrate leaching was negligible. At the end of the growing season, nutrients were translocated to the rhizomes and, in the case of M. giganteus, recycled to the soil in shed leaves. Consequently the nutrient content of the crop offtake was low. It was calculated that the N, P and K requirements of a M. x giganteus crop producing an above-ground harvest of 1.5 kg m{sup -2} dry matter would be 9.2, .3 and 20.4 g m{sup -2} respectively. The corresponding nutrient requirements for S. cynosuroides would be 7.5, 1.7 and 8.8 g m{sup -2}. Except for the K requirements of M. x giganteus, the N, P and K demands of both species were less than those of typical graminaceous crops, including maize. (Author)

  16. Magnetospherically reflected chorus waves revealed by ray tracing with CLUSTER data

    Directory of Open Access Journals (Sweden)

    M. Parrot

    Full Text Available This paper is related to the propagation characteristics of a chorus emission recorded simultaneously by the 4 satellites of the CLUSTER mission on 29 October 2001 between 01:00 and 05:00 UT. During this day, the spacecraft (SC 1, 2, and 4 are relatively close to each other but SC3 has been delayed by half an hour. We use the data recorded aboard CLUSTER by the STAFF spectrum analyser. This instrument provides the cross spectral matrix of three magnetic and two electric field components. Dedicated software processes this spectral matrix in order to determine the wave normal directions relative to the Earth’s magnetic field. This calculation is done for the 4 satellites at different times and different frequencies and allows us to check the directions of these waves. Measurements around the magnetic equator show that the parallel component of the Poynting vector changes its sign when the satellites cross the equator region. It indicates that the chorus waves propagate away from this region which is considered as the source area of these emissions. This is valid for the most intense waves observed on the magnetic and electric power spectrograms. But it is also observed on SC1, SC2, and SC4 that lower intensity waves propagate toward the equator simultaneously with the SC3 intense chorus waves propagating away from the equator. Both waves are at the same frequency. Using the wave normal directions of these waves, a ray tracing study shows that the waves observed by SC1, SC2, and SC4 cross the equatorial plane at the same location as the waves observed by SC3. SC3 which is 30 minutes late observes the waves that originate first from the equator; meanwhile, SC1, SC2, and SC4 observe the same waves that have suffered a Lower Hybrid Resonance (LHR reflection at low altitudes (based on the ray tracing analysis and now return to the equator at a different location with a lower intensity. Similar phenomenon is observed when all SC are on the other side

  17. 浅谈合唱指挥教学的改革与创新%The reform and innovation of chorus direction teaching

    Institute of Scientific and Technical Information of China (English)

    应玫

    2012-01-01

      The reform and innovation of teaching of chorus and conducting, has important significance to promote the teaching of chorus and conducting level. This paper first analyzes the main problems in current teaching of chorus and conducting, and then an antidote against the disease, to put forward corresponding countermeasures on how to reform and innovate the chorus teaching.%  改革与创新合唱指挥教学,对于促进合唱指挥教学水平的提升具有重要意义。本文首先分析了当前合唱指挥教学中存在的主要问题,然后对症下药,对如何改革与创新合唱指挥教学提出了相应对策

  18. Decrease of VLF transmitter signal and Chorus-whistler waves before l'Aquila earthquake occurrence

    Directory of Open Access Journals (Sweden)

    M. Y. Boudjada

    2010-07-01

    Full Text Available We investigate the VLF emissions observed by the Instrument Champ Electrique (ICE experiment onboard the DEMETER micro-satellite. We analyze intensity level variation 10 days before and after the occurrence of l'Aquila earthquake (EQ. We found a clear decrease of the VLF received signal related to ionospheric whistler mode (mainly Chorus emission and to signal transmitted by the DFY VLF station in Germany, few days (more than one week before the earthquake. The VLF power spectral density decreases of more than two orders of magnitude until the EQ, and it recovers to normal levels just after the EQ occurrence. The geomagnetic activity is principally weak four days before EQ and increases again one day before l'Aquila seismic event. Our results are discussed in the frame of short- and long-terms earthquakes prediction focusing on the crucial role of the magnetic field of the Earth.

  19. Identification of GBV-D, a novel GB-like flavivirus from old world frugivorous bats (Pteropus giganteus in Bangladesh.

    Directory of Open Access Journals (Sweden)

    Jonathan H Epstein

    Full Text Available Bats are reservoirs for a wide range of zoonotic agents including lyssa-, henipah-, SARS-like corona-, Marburg-, Ebola-, and astroviruses. In an effort to survey for the presence of other infectious agents, known and unknown, we screened sera from 16 Pteropus giganteus bats from Faridpur, Bangladesh, using high-throughput pyrosequencing. Sequence analyses indicated the presence of a previously undescribed virus that has approximately 50% identity at the amino acid level to GB virus A and C (GBV-A and -C. Viral nucleic acid was present in 5 of 98 sera (5% from a single colony of free-ranging bats. Infection was not associated with evidence of hepatitis or hepatic dysfunction. Phylogenetic analysis indicates that this first GBV-like flavivirus reported in bats constitutes a distinct species within the Flaviviridae family and is ancestral to the GBV-A and -C virus clades.

  20. Developing County-level Water Footprints of Biofuel Produced from Switchgrass and Miscanthus x Giganteus in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Wu, May M. [Argonne National Lab. (ANL), Argonne, IL (United States); Chiu, Yi-Wen [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-09-30

    Perennial grass has been proposed as a potential candidate for producing cellulosic biofuel because of its promising productivity and benefits to water quality, and because it is a non-food feedstock. While extensive research focuses on selecting and developing species and conversion technologies, the impact of grass-based biofuel production on water resources remains less clear. As feedstock growth requires water and the type of water consumed may vary considerably from region to region, water use must be characterized with spatial resolution and on a fuel production basis. This report summarizes a study that assesses the impact of biofuel production on water resource use and water quality at county, state, and regional scales by developing a water footprint of biofuel produced from switchgrass and Miscanthus × giganteus via biochemical conversion.

  1. Chorus-Driven Outer Radiation Belt Electron Dynamics at Different L-Shells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Sai; XIAO Fu-Liang

    2010-01-01

    @@ Energetic outer radiation belt electron phase space density(PSD)evolution due to interaction with whistler-mode chorus at different L-shells is investigated by solving the diffusion equation including cross diffusion terms.It is found that the difference of diffusion rates for different L-shells occurs primarily at pitch angles 0°-50° and around 90°.In particular,diffusion rates for L = 6.5 are found to be 5-10 times larger than that for L = 3.5 at these pitch angles.In the presence of cross terms,PSD for~MeV electrons after 24 h decreases by about 25,12,10 and 8 times at L = 3.5,4.5,5.5 and 6.5 near the loss cone,and increases by about 55,45,30 and 20 times at larger pitch angles,respectively.After 24 h,the ratios between~MeV electron PSDs from simulations without and with cross diffusion at L = 3.5,4.5,5.5 and 6.5 are about 350,600,800 and 800 near the loss cone,and become 5,5.5,6.5 and 8 at pitch angle 90°,respectively.These results demonstrate that neglect of cross diffusion generally results in the overestimate of PSD,and the cross diffusion plays a more significant role in the resonant interaction between chorus waves and outer radiation belt electrons at larger L.

  2. Arthromitus (Bacillus cereus) symbionts in the cockroach Blaberus giganteus: dietary influences on bacterial development and population density

    Science.gov (United States)

    Feinberg, L.; Jorgensen, J.; Haselton, A.; Pitt, A.; Rudner, R.; Margulis, L.

    1999-01-01

    The filamentous spore-forming bacterium Arthromitus, discovered in termites, millipedes, sow bugs and other soil-dwelling arthropods by Leidy (1850), is the intestinal stage of Bacillus cereus. We extend the range of Arthromitus habitats to include the hindgut of Blaberus giganteus, the large tropical American cockroach. The occurrence and morphology of the intestinal form of the bacillus were compared in individual cockroaches (n=24) placed on four different diet regimes: diurnally maintained insects fed (1) dog food, (2) soy protein only, (3)purified cellulose only, and (4) a dog food-fed group maintained in continuous darkness. Food quality exerted strong influence on population densities and developmental stages of the filamentous bacterium and on fecal pellet composition. The most dramatic rise in Arthromitus populations, defined as the spore-forming filament intestinal stage, occurred in adult cockroaches kept in the dark on a dog food diet. Limited intake of cellulose or protein alone reduced both the frequency of Arthromitus filaments and the rate of weight gain of the insects. Spores isolated from termites, sow bugs, cockroaches and moths, grown on various hard surfaces display a branching mobility and resistance to antibiotics characteristic to group I Bacilli whose members include B. cereus, B. circulans, B. alvei and B. macerans. DNA isolated from pure cultures of these bacilli taken from the guts of Blaberus giganteus (cockroach), Junonia coenia (moth), Porcellio scaber (sow bug) and Cryptotermes brevis (termite) and subjected to Southern hybridization with a 23S-5S B. subtilis ribosomal sequence probe verified that they are indistinguishable from laboratory strains of Bacillus cereus.

  3. Comparison of the onset of dawn chorus of bulbuls and house sparrows in two different geographical locations: effect of climate, noise and light pollution

    Directory of Open Access Journals (Sweden)

    Nail M. Hasan

    2011-04-01

    Full Text Available The onset of dawn chorus was studied for a period of fourteen months for bulbuls (Pycnonotidae and house sparrows (Passer domesticus in two different geographical locations. One is very quiet and semi lit place in the suburbs of the small Mediterranean city of Tulkarem/Palestinian Authority. The other location is comparatively noisy and very well lit place in the Ar-Rayyan urban district of the city of Riyadh/ Saudi Arabia where desert climate prevails. This study is the first of its kind and clearly shows that the timing of dawn chorus is similar for autumn and winter seasons in both locations but major differences were observed from February until September between the two locations. It can be concluded that very early timing of dawn chorus during spring / summer for the Riyadh location cannot only be attributed to breeding season and is temperature dependent (strong positive correlation, r>0.6. The similarities for autumn and early winter between the two locations is very interesting in that it is not in agreement with the notion that big cities (urbanization influence the timing of dawn chorus due to noise and light pollution. This emphasizes that dawn chorus is a complex process and that change in the onset and pattern of dawn chorus can not merely be attributed to one variable such as noise or light pollution alone.

  4. Chorus wave-normal statistics in the Earth's radiation belts from ray tracing technique

    Directory of Open Access Journals (Sweden)

    H. Breuillard

    2012-08-01

    Full Text Available Discrete ELF/VLF (Extremely Low Frequency/Very Low Frequency chorus emissions are one of the most intense electromagnetic plasma waves observed in radiation belts and in the outer terrestrial magnetosphere. These waves play a crucial role in the dynamics of radiation belts, and are responsible for the loss and the acceleration of energetic electrons. The objective of our study is to reconstruct the realistic distribution of chorus wave-normals in radiation belts for all magnetic latitudes. To achieve this aim, the data from the electric and magnetic field measurements onboard Cluster satellite are used to determine the wave-vector distribution of the chorus signal around the equator region. Then the propagation of such a wave packet is modeled using three-dimensional ray tracing technique, which employs K. Rönnmark's WHAMP to solve hot plasma dispersion relation along the wave packet trajectory. The observed chorus wave distributions close to waves source are first fitted to form the initial conditions which then propagate numerically through the inner magnetosphere in the frame of the WKB approximation. Ray tracing technique allows one to reconstruct wave packet properties (electric and magnetic fields, width of the wave packet in k-space, etc. along the propagation path. The calculations show the spatial spreading of the signal energy due to propagation in the inhomogeneous and anisotropic magnetized plasma. Comparison of wave-normal distribution obtained from ray tracing technique with Cluster observations up to 40° latitude demonstrates the reliability of our approach and applied numerical schemes.

  5. Exotic molluscs (Mollusca, Gastropoda et Bivalvia in Santa Catarina State, Southern Brazil region: check list and regional spatial distribution

    Directory of Open Access Journals (Sweden)

    A. Ignacio Agudo-Padrón

    2011-06-01

    Full Text Available A total of twenty-one exotic mollusc taxa were assessed for Santa Catarina State (SC, fifteen Gastropoda andsix Bivalvia (twelve terrestrial, five limnic/freshwater - three gastropods and two bivalves, and four marinebivalves. Of these, fourteen are confirmed as invasive species (nine terrestrial, three limnic/freshwater, andtwo marine.

  6. Die Nacktschneckengesellschaften in NW-Deutschland (Gastropoda: Milacidae, Boettgerillidae, Limacidae, Agriolimacidae, Arionidae): ein Ergebnis der NRW-Kartierung

    NARCIS (Netherlands)

    Kappes, H.; Kobialka, H.

    2009-01-01

    Slug assemblages in NW Germany (Gastropoda: Milacidae, Boettgerillidae, Limacidae, Agriolimacidae, Arionidae): a result of the mapping survey of Northrhine-Westphalia. This survey provides information on inter-specific associations of slugs on a regional data base. Most of the data originate from th

  7. The evaluation of growth and phytoextraction potential of Miscanthus x giganteus and Sida hermaphrodita on soil contaminated simultaneously with Cd, Cu, Ni, Pb, and Zn.

    Science.gov (United States)

    Kocoń, Anna; Jurga, Beata

    2017-02-01

    One of the cheapest, environmentally friendly methods for cleaning an environment polluted by heavy metals is phytoextraction. It builds on the uptake of pollutants from the soil by the plants, which are able to grow under conditions of high concentrations of toxic metals. The aim of this work was to assess the possibility of growing and phytoextraction potential of Miscanthus x giganteus and Sida hermaphrodita cultivated on two different soils contaminated with five heavy metals simultaneously: Cd, Cu, Ni, Pb, and Zn. A 3-year microplot experiment with two perennial energy crops, M. x giganteus and S. hermaphrodita, was conducted in the experimental station of IUNG-PIB in Poland (5° 25' N, 21° 58 'E), in the years of 2008-2010. Miscanthus was found more tolerant to concomitant soil contamination with heavy metals and produced almost double biomass than Sida in all three tested years, independent of soil type. Miscanthus collected greater amount of heavy metals (except for cadmium) in the biomass than Sida. Both energy crops absorb high levels of zinc, lower levels of lead, copper, and nickel, and absorbed cadmium at least, generally more metals were taken from the sandy soil, where plants also yielded better. Photosynthesis net rate of Miscanthus was on average 40% higher compared to Sida. Obtained results indicate that M. x giganteus and S. hermaphrodita can successfully be grown on moderately contaminated soil with heavy metals.

  8. Intensification of dayside diffuse auroral precipitation: contribution of dayside Whistler-mode chorus waves in realistic magnetic fields

    Directory of Open Access Journals (Sweden)

    R. Shi

    2012-09-01

    Full Text Available Compared to the recently improved understanding of nightside diffuse aurora, the mechanism(s responsible for dayside diffuse aurora remains poorly understood. While dayside chorus has been thought as a potential major contributor to dayside diffuse auroral precipitation, quantitative analyses of the role of chorus wave scattering have not been carefully performed. In this study we investigate a dayside diffuse auroral intensification event observed by the Chinese Arctic Yellow River Station (YRS all-sky imagers (ASI on 7 January 2005 and capture a substantial increase in diffuse auroral intensity at the 557.7 nm wavelength that occurred over almost the entire ASI field-of-view near 09:24 UT, i.e., ~12:24 MLT. Computation of bounce-averaged resonant scattering rates by dayside chorus emissions using realistic magnetic field models demonstrates that dayside chorus scattering can produce intense precipitation losses of plasma sheet electrons on timescales of hours (even approaching the strong diffusion limit over a broad range of both energy and pitch angle, specifically, from ~1 keV to 50 keV with equatorial pitch angles from the loss cone to up to ~85° depending on electron energy. Subsequent estimate of loss cone filling index indicates that the loss cone can be substantially filled, due to dayside chorus driven pitch angle scattering, at a rate of ≥0.8 for electrons from ~500 eV to 50 keV that exactly covers the precipitating electrons for the excitation of green-line diffuse aurora. Estimate of electron precipitation flux at different energy levels, based on loss cone filling index profile and typical dayside electron distribution observed by THEMIS spacecraft under similar conditions, gives a total precipitation electron energy flux of the order of 0.1 erg cm−2 s−1 with ~1 keV characteristic energy (especially when using T01s, which can be very likely to cause intense green-line diffuse aurora activity on the

  9. LARVAS DE DIGENEA EN Melanoides tuberculata (GASTROPODA: THIARIDAE EN MEDELLÍN, COLOMBIA Larval stages of digenea from Melanoides tuberculata (Gastropoda: Thiaridae in Medellín, Colombia

    Directory of Open Access Journals (Sweden)

    DANIELA VERGARA

    Full Text Available Se describen las larvas de digeneos que se obtuvieron en Melanoides tuberculata (Gastropoda: Thiaridae, molusco dulceacuícola del que se colectaron 125 especímenes en el lago del Jardín Botánico Joaquín Antonio Uribe de Medellín. En el laboratorio se individualizaron y se estimuló la emisión cercariana con una fuente luminosa. El 9,6 % de los caracoles emitió cercarias. Los moluscos emisores se sacrificaron para obtener los demás estadios larvarios. Las larvas se montaron al microscopio, se midieron y luego se dibujaron. Los caracteres morfológicos permitieron establecer la presencia de Centrocestus formosanus (Heterophyidae y de dos Philophthalmidae. Uno de estos es primer registro para Colombia. Se confirma la sensibilidad de M. tuberculata a infecciones por digeneos, así como la especificidad de los filoftálmidos por moluscos hospedadores de la superfamilia Cerithioidea.The larvae of two trematodes found in the freshwater mollusk Melanoides tuberculata (Gastropoda: Thiaridae are described. 125 snails from the Medellin’s Botanical Garden Joaquín Antonio Uribe were collected. In the laboratory, each individual was placed alone and stimulated with light in order to have cercaria emission. 9.6% of the snails released cercariae. These were separated in three morphologies. From each one, 15 individuals were measured and drawn. Photographs were taken. Based on their morphological characteritics the presence of Centrocestus formosanus (Heterophyidae was determined. The other two morphologies were classified in the family Philophthalmidae. One of them constitutes the first register for Colombia. The sensibility of M. tuberculata to infections by digeneans, and the specificity of the family Philophthalmidae to mollusk hosts of the superfamily Cerithioidea are confirmed

  10. Rapid increase in relativistic electron flux controlled by nonlinear phase trapping of whistler chorus elements

    Science.gov (United States)

    Saito, Shinji; Miyoshi, Yoshizumi; Seki, Kanako

    2016-07-01

    Wave-particle interactions with whistler chorus waves are believed to provide a primary acceleration for electrons in the outer radiation belt. Previous models for flux enhancement of the radiation belt have assumed the stochastic process as a diffusion manner of successive random-phase interactions, but physical mechanisms for the acceleration are not fully incorporated in these models because of the lack of a nonlinear scattering process. Here we report rapid increase in relativistic electron flux by using an innovative computer simulation model that incorporates not only diffusive process but also nonlinear scattering processes. The simulations show that three types of scattering simultaneously occur, which are diffusive, phase trapping, and phase bunching. It is found that the phase trapping is the most efficient mechanism to produce the MeV electrons rapidly in the scattering processes. The electrons are accelerated from 400 keV to over 1 MeV in time scale less than 60 s. On the other hand, as the phase trapping is suppressed by the breaking of relative phase angle between waves and gyrating electrons during the interaction, the increase of electron flux at MeV energy is clearly reduced. Our simulations conclude that the phase-trapping process causes a significant effect for the increase in relativistic electron flux and suggest that a quasi-linear diffusion model is not always valid to fully describe the relativistic electron acceleration.

  11. Factors influencing survival and mark retention in postmetamorphic boreal chorus frogs

    Science.gov (United States)

    Swanson, Jennifer E; Bailey, Larissa L.; Muths, Erin L.; Funk, W. Chris

    2013-01-01

    The ability to track individual animals is crucial in many field studies and often requires applying marks to captured individuals. Toe clipping has historically been a standard marking method for wild amphibian populations, but more recent marking methods include visual implant elastomer and photo identification. Unfortunately, few studies have investigated the influence and effectiveness of marking methods for recently metamorphosed individuals and as a result little is known about this life-history phase for most amphibians. Our focus was to explore survival probabilities, mark retention, and mark migration in postmetamorphic Boreal Chorus Frogs (Psuedacris maculata) in a laboratory setting. One hundred forty-seven individuals were assigned randomly to two treatment groups or a control group. Frogs in the first treatment group were marked with visual implant elastomer, while frogs in the second treatment group were toe clipped. Growth and mortality were recorded for one year and resulting data were analyzed using known-fate models in Program MARK. Model selection results suggested that survival probabilities of frogs varied with time and showed some variation among marking treatments. We found that frogs with multiple toes clipped on the same foot had lower survival probabilities than individuals in other treatments, but individuals can be marked by clipping a single toe on two different feet without any mark loss or negative survival effects. Individuals treated with visual implant elastomer had a mark migration rate of 4% and mark loss rate of 6%, and also showed very little negative survival impacts relative to control individuals.

  12. Optimization of ammonia fiber expansion (AFEX) pretreatment and enzymatic hydrolysis of Miscanthus x giganteus to fermentable sugars.

    Science.gov (United States)

    Murnen, Hannah K; Balan, Venkatesh; Chundawat, Shishir P S; Bals, Bryan; Sousa, Leonardo da Costa; Dale, Bruce E

    2007-01-01

    Miscanthus x giganteus is a tall perennial grass whose suitability as an energy crop is presently being appraised. There is very little information on the effect of pretreatment and enzymatic saccharification of Miscanthus to produce fermentable sugars. This paper reports sugar yields during enzymatic hydrolysis from ammonia fiber expansion (AFEX) pretreated Miscanthus. Pretreatment conditions including temperature, moisture, ammonia loading, residence time, and enzyme loadings are varied to maximize hydrolysis yields. In addition, further treatments such as soaking the biomass prior to AFEX as well as washing the pretreated material were also attempted to improve sugar yields. The optimal AFEX conditions determined were 160 degrees C, 2:1 (w/w) ammonia to biomass loading, 233% moisture (dry weight basis), and 5 min reaction time for water-soaked Miscanthus. Approximately 96% glucan and 81% xylan conversions were achieved after 168 h enzymatic hydrolysis at 1% glucan loading using 15 FPU/(g of glucan) of cellulase and 64 p-NPGU/(g of glucan) of beta-glucosidase along with xylanase and tween-80 supplementation. A mass balance for the AFEX pretreatment and enzymatic hydrolysis process is presented.

  13. Purification and Characterization of a Unique Pectin Lyase from Aspergillus giganteus Able to Release Unsaturated Monogalacturonate during Pectin Degradation.

    Science.gov (United States)

    Pedrolli, Danielle Biscaro; Carmona, Eleonora Cano

    2014-01-01

    A pectin lyase, named PLIII, was purified to homogeneity from the culture filtrate of Aspergillus giganteus grown in submerged culture containing orange peel waste as carbon source. PLIII was able to digest apple pectin and citrus pectins with different degrees of methyl esterification. Interestingly, the PLIII activity was stimulated in the presence of some divalent cations including Pb(2+) and was not significantly affected by Hg(2+). Like other pectin lyases, PLIII is stimulated by but is not dependent on Ca(2+). The main soluble product released during the degradation of pectic substances promoted by the PLIII is compatible with an unsaturated monogalacturonate. PLIII is a unique enzyme able to release unsaturated monogalacturonate as the only soluble product during the degradation of pectic substances; therefore, PLIII was classified as an exo-pectin lyase. To our knowledge, this is the first characterization of an exo-pectin lyase. The PLIII described in this work is potentially useful for ethanol production from pectin-rich biomass, besides other common applications for alkaline pectinases like preparation of textile fibers, coffee and tea fermentation, vegetable oil extraction, and the treatment of pulp in papermaking.

  14. Purification and Characterization of a Unique Pectin Lyase from Aspergillus giganteus Able to Release Unsaturated Monogalacturonate during Pectin Degradation

    Directory of Open Access Journals (Sweden)

    Danielle Biscaro Pedrolli

    2014-01-01

    Full Text Available A pectin lyase, named PLIII, was purified to homogeneity from the culture filtrate of Aspergillus giganteus grown in submerged culture containing orange peel waste as carbon source. PLIII was able to digest apple pectin and citrus pectins with different degrees of methyl esterification. Interestingly, the PLIII activity was stimulated in the presence of some divalent cations including Pb2+ and was not significantly affected by Hg2+. Like other pectin lyases, PLIII is stimulated by but is not dependent on Ca2+. The main soluble product released during the degradation of pectic substances promoted by the PLIII is compatible with an unsaturated monogalacturonate. PLIII is a unique enzyme able to release unsaturated monogalacturonate as the only soluble product during the degradation of pectic substances; therefore, PLIII was classified as an exo-pectin lyase. To our knowledge, this is the first characterization of an exo-pectin lyase. The PLIII described in this work is potentially useful for ethanol production from pectin-rich biomass, besides other common applications for alkaline pectinases like preparation of textile fibers, coffee and tea fermentation, vegetable oil extraction, and the treatment of pulp in papermaking.

  15. Developmental and Post-Eruptive Defects in Molar Enamel of Free-Ranging Eastern Grey Kangaroos (Macropus giganteus Exposed to High Environmental Levels of Fluoride.

    Directory of Open Access Journals (Sweden)

    Uwe Kierdorf

    Full Text Available Dental fluorosis has recently been diagnosed in wild marsupials inhabiting a high-fluoride area in Victoria, Australia. Information on the histopathology of fluorotic marsupial enamel has thus far not been available. This study analyzed the developmental and post-eruptive defects in fluorotic molar enamel of eastern grey kangaroos (Macropus giganteus from the same high-fluoride area using light microscopy and backscattered electron imaging in the scanning electron microscope. The fluorotic enamel exhibited a brownish to blackish discolouration due to post-eruptive infiltration of stains from the oral cavity and was less resistant to wear than normally mineralized enamel of kangaroos from low-fluoride areas. Developmental defects of enamel included enamel hypoplasia and a pronounced hypomineralization of the outer (sub-surface enamel underneath a thin rim of well-mineralized surface enamel. While the hypoplastic defects denote a disturbance of ameloblast function during the secretory stage of amelogenesis, the hypomineralization is attributed to an impairment of enamel maturation. In addition to hypoplastic defects, the fluorotic molars also exhibited numerous post-eruptive enamel defects due to the flaking-off of portions of the outer, hypomineralized enamel layer during mastication. The macroscopic and histopathological lesions in fluorotic enamel of M. giganteus match those previously described for placental mammals. It is therefore concluded that there exist no principal differences in the pathogenic mechanisms of dental fluorosis between marsupial and placental mammals. The regular occurrence of hypomineralized, opaque outer enamel in the teeth of M. giganteus and other macropodids must be considered in the differential diagnosis of dental fluorosis in these species.

  16. Developmental and Post-Eruptive Defects in Molar Enamel of Free-Ranging Eastern Grey Kangaroos (Macropus giganteus) Exposed to High Environmental Levels of Fluoride

    Science.gov (United States)

    Kierdorf, Uwe; Death, Clare; Hufschmid, Jasmin; Witzel, Carsten; Kierdorf, Horst

    2016-01-01

    Dental fluorosis has recently been diagnosed in wild marsupials inhabiting a high-fluoride area in Victoria, Australia. Information on the histopathology of fluorotic marsupial enamel has thus far not been available. This study analyzed the developmental and post-eruptive defects in fluorotic molar enamel of eastern grey kangaroos (Macropus giganteus) from the same high-fluoride area using light microscopy and backscattered electron imaging in the scanning electron microscope. The fluorotic enamel exhibited a brownish to blackish discolouration due to post-eruptive infiltration of stains from the oral cavity and was less resistant to wear than normally mineralized enamel of kangaroos from low-fluoride areas. Developmental defects of enamel included enamel hypoplasia and a pronounced hypomineralization of the outer (sub-surface) enamel underneath a thin rim of well-mineralized surface enamel. While the hypoplastic defects denote a disturbance of ameloblast function during the secretory stage of amelogenesis, the hypomineralization is attributed to an impairment of enamel maturation. In addition to hypoplastic defects, the fluorotic molars also exhibited numerous post-eruptive enamel defects due to the flaking-off of portions of the outer, hypomineralized enamel layer during mastication. The macroscopic and histopathological lesions in fluorotic enamel of M. giganteus match those previously described for placental mammals. It is therefore concluded that there exist no principal differences in the pathogenic mechanisms of dental fluorosis between marsupial and placental mammals. The regular occurrence of hypomineralized, opaque outer enamel in the teeth of M. giganteus and other macropodids must be considered in the differential diagnosis of dental fluorosis in these species. PMID:26895178

  17. Developmental and Post-Eruptive Defects in Molar Enamel of Free-Ranging Eastern Grey Kangaroos (Macropus giganteus) Exposed to High Environmental Levels of Fluoride.

    Science.gov (United States)

    Kierdorf, Uwe; Death, Clare; Hufschmid, Jasmin; Witzel, Carsten; Kierdorf, Horst

    2016-01-01

    Dental fluorosis has recently been diagnosed in wild marsupials inhabiting a high-fluoride area in Victoria, Australia. Information on the histopathology of fluorotic marsupial enamel has thus far not been available. This study analyzed the developmental and post-eruptive defects in fluorotic molar enamel of eastern grey kangaroos (Macropus giganteus) from the same high-fluoride area using light microscopy and backscattered electron imaging in the scanning electron microscope. The fluorotic enamel exhibited a brownish to blackish discolouration due to post-eruptive infiltration of stains from the oral cavity and was less resistant to wear than normally mineralized enamel of kangaroos from low-fluoride areas. Developmental defects of enamel included enamel hypoplasia and a pronounced hypomineralization of the outer (sub-surface) enamel underneath a thin rim of well-mineralized surface enamel. While the hypoplastic defects denote a disturbance of ameloblast function during the secretory stage of amelogenesis, the hypomineralization is attributed to an impairment of enamel maturation. In addition to hypoplastic defects, the fluorotic molars also exhibited numerous post-eruptive enamel defects due to the flaking-off of portions of the outer, hypomineralized enamel layer during mastication. The macroscopic and histopathological lesions in fluorotic enamel of M. giganteus match those previously described for placental mammals. It is therefore concluded that there exist no principal differences in the pathogenic mechanisms of dental fluorosis between marsupial and placental mammals. The regular occurrence of hypomineralized, opaque outer enamel in the teeth of M. giganteus and other macropodids must be considered in the differential diagnosis of dental fluorosis in these species.

  18. Crystallization in organo-mineral micro-domains in the crossed-lamellar layer of Nerita undata (Gastropoda, Neritopsina).

    Science.gov (United States)

    Nouet, Julius; Baronnet, Alain; Howard, Lauren

    2012-02-01

    Crossed-lamellar shell microstructure consists of a sophisticated arrangement of interspersed lamellae, which is very commonly found in Gastropoda or Bivalvia shell layers. Its smallest constitutive microstructural units are usually described as sub-micrometric fibers, or rods, and form very ordered and regular patterns. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) imaging confirms the presence of even smaller building units in the form of organo-mineral granules, and we further investigate their internal structure within aragonite crossed-lamellar internal layer of Nerita undata (Gastropoda, Neritopsina) shell. Their coalescence may have controlled anisotropically the propagation of the crystallographic coherence through this complex microstructure, as suggested by the propagation of the microtwinning pattern between neighboring granules.

  19. The diet of the Indian Flying Fox Pteropus giganteus (Brünnich. 1782 (Chiroptera: Pteropodidae in Myanmar - conflicts with local people?

    Directory of Open Access Journals (Sweden)

    Sein Sein Win

    2015-07-01

    Full Text Available The diet of Pteropus giganteus from three roosts in Mandalay Region, central Myanmar was investigated for over two years by examining feeding remains in and around two villages.  It consists of 24 species of fruits, six species of flowers and three of leaves.  Of these, 13 species of fruits are eaten by the local people, three of which are also marketed.  Two are used in traditional medicine and one for stuffing pillows. Most dietary plants are native, mangoes are seasonally superabundant and are eaten in large numbers.  Interviews revealed no evidence of conflict between bats and villagers. 

  20. ANÁLISE QUÍMICA DO BAMBU-GIGANTE (DENDROCALAMUS GIGANTEUS WALL. EX MUNRO EM DIFERENTES IDADES

    Directory of Open Access Journals (Sweden)

    Nelson Potenciano Marinho

    2012-01-01

    Full Text Available Bamboo is a monocotyledon of tropical origin which grows fast and is considered an important environment regenerator because of its root system. Dendrocalamus giganteus is popular learned by giant bamboo, being a big bush species, its culms can be from 24 to 40 meters high, with diameters from 10 and 20 centimeters. This work had the objective of a chemical analysis from giant bamboo to aim at giving information from its chemical composition from 2 to 6 years of age. Bamboo culms were collected in the Agriculture Experimental area of the Mechanical Engineering Department of UNESP -Bauru, where it is carried out the systematic handling from different bamboo species to this plant research and divulgation. Samples from base were collected from 2 and 6 years in the same bush, in total of 5 samples, with 2 high meters each, cropped in March, half moon. Chemical analysis was done with internodes using TAPPI Methods. The average percentage extractives from hot water, cool water, total extractives and ash content were not related to the age. The major percentage of hot water extractives, with values of 12.04%, cold water extractives, with 10.25%, and total extractives, with 12.91%, was observed by the age of two years. The major ash content was obtained on three years, with value of 1.09%. The mean value of NaOH extractives decreased from 25.72%, in two years, to 20.17% at six years old. The same behavior was observed for ethanol toluene extractives, decreasing from 10.91% to 4.61%. The mean lignin content was not influenced by age, varying from 22.66 to 24.11%.

  1. Caracterização físico-mecânica do laminado colado de bambu (Dendrocalamus giganteus.

    Directory of Open Access Journals (Sweden)

    Juarez Benigno Paes

    2009-09-01

    Full Text Available Normal 0 21 MicrosoftInternetExplorer4 Esta pesquisa teve como objetivo avaliar a influência do tratamento preservativo e do tipo de adesivo nas propriedades físico-mecânicas do laminado colado, confeccionado com o bambu Dendrocalamus giganteus. Para tanto, colmos de bambu foram tratados pelo método de imersão em produto químico (solução de 1% de ingredientes ativos de borato de cobre cromatado - CCB e em água, durante 15 dias. Dos colmos tratados, foram retiradas as camadas externa e interna, obtendo-se lâminas com espessuras de 4 mm, comprimento de 45 cm e largura de 5 cm. Para a colagem das lâminas, utilizaram-se os adesivos "Cascophen RS" (resorcinol-formol e "Cascorez-Extra" (acetato polivinílico. O adesivo à base de resorcinol-formol proporcionou maior resistência à umidade ao BLC, quando comparado àquele à base de acetato polivinílico, tendo as amostras provenientes de peças tratadas com CCB sido mais estáveis que as tratadas com água. Dentre as propriedades mecânicas testadas, o adesivo apresentou resultado significativo para o cisalhamento na linha de cola e o tratamento preservativo para o MOE. A interação dos fatores adesivo e tratamento foi significativa para o MOE, resistência a compressão paralela ao cisalhamento na linha de cola, tendo as peças tratadas com água e aderidas com resorcinol-formol apresentado melhores resultados para o MOE e compressão paralela às fibras e aquelas tratadas com CCB, para o cisalhamento na linha de cola.

  2. Refuge or reservoir? The potential impacts of the biofuel crop Miscanthus x giganteus on a major pest of maize.

    Directory of Open Access Journals (Sweden)

    Joseph L Spencer

    Full Text Available BACKGROUND: Interest in the cultivation of biomass crops like the C4 grass Miscanthus x giganteus (Miscanthus is increasing as global demand for biofuel grows. In the US, Miscanthus is promoted as a crop well-suited to the Corn Belt where it could be cultivated on marginal land interposed with maize and soybean. Interactions (direct and indirect of Miscanthus, maize, and the major Corn Belt pest of maize, the western corn rootworm, (Diabrotica virgifera virgifera LeConte, WCR are unknown. Adding a perennial grass/biomass crop to this system is concerning since WCR is adapted to the continuous availability of its grass host, maize (Zea mays. METHODOLOGY/PRINCIPAL FINDINGS: In a greenhouse and field study, we investigated WCR development and oviposition on Miscanthus. The suitability of Miscanthus for WCR development varied across different WCR populations. Data trends indicate that WCR populations that express behavioural resistance to crop rotation performed as well on Miscanthus as on maize. Over the entire study, total adult WCR emergence from Miscanthus (212 WCR was 29.6% of that from maize (717 WCR. Adult dry weight was 75-80% that of WCR from maize; female emergence patterns on Miscanthus were similar to females developing on maize. There was no difference in the mean no. of WCR eggs laid at the base of Miscanthus and maize in the field. CONCLUSIONS/SIGNIFICANCE: Field oviposition and significant WCR emergence from Miscanthus raises many questions about the nature of likely interactions between Miscanthus, maize and WCR and the potential for Miscanthus to act as a refuge or reservoir for Corn Belt WCR. Responsible consideration of the benefits and risks associated with Corn Belt Miscanthus are critical to protecting an agroecosystem that we depend on for food, feed, and increasingly, fuel. Implications for European agroecosystems in which Miscanthus is being proposed are also discussed in light of the WCR's recent invasion into Europe.

  3. Influence of light and nitrogen on the photosynthetic efficiency in the C4 plant Miscanthus × giganteus.

    Science.gov (United States)

    Ma, Jian-Ying; Sun, Wei; Koteyeva, Nuria K; Voznesenskaya, Elena; Stutz, Samantha S; Gandin, Anthony; Smith-Moritz, Andreia M; Heazlewood, Joshua L; Cousins, Asaph B

    2017-01-01

    There are numerous studies describing how growth conditions influence the efficiency of C4 photosynthesis. However, it remains unclear how changes in the biochemical capacity versus leaf anatomy drives this acclimation. Therefore, the aim of this study was to determine how growth light and nitrogen availability influence leaf anatomy, biochemistry and the efficiency of the CO2 concentrating mechanism in Miscanthus × giganteus. There was an increase in the mesophyll cell wall surface area but not cell well thickness in the high-light (HL) compared to the low-light (LL) grown plants suggesting a higher mesophyll conductance in the HL plants, which also had greater photosynthetic capacity. Additionally, the HL plants had greater surface area and thickness of bundle-sheath cell walls compared to LL plants, suggesting limited differences in bundle-sheath CO2 conductance because the increased area was offset by thicker cell walls. The gas exchange estimates of phosphoenolpyruvate carboxylase (PEPc) activity were significantly less than the in vitro PEPc activity, suggesting limited substrate availability in the leaf due to low mesophyll CO2 conductance. Finally, leakiness was similar across all growth conditions and generally did not change under the different measurement light conditions. However, differences in the stable isotope composition of leaf material did not correlate with leakiness indicating that dry matter isotope measurements are not a good proxy for leakiness. Taken together, these data suggest that the CO2 concentrating mechanism in Miscanthus is robust under low-light and limited nitrogen growth conditions, and that the observed changes in leaf anatomy and biochemistry likely help to maintain this efficiency.

  4. Persistent organic pollutants in blood samples of Southern Giant Petrels (Macronectes giganteus) from the South Shetland Islands, Antarctica.

    Science.gov (United States)

    Colabuono, Fernanda I; Vander Pol, Stacy S; Huncik, Kevin M; Taniguchi, Satie; Petry, Maria V; Kucklick, John R; Montone, Rosalinda C

    2016-09-01

    Seabirds play an important role as top consumers in the food web and can be used as biomonitors of exposure to pollutants. Contamination studies involving non-destructive sampling methods are of considerable importance, allowing better evaluation of the levels of pollutants and their toxic effects. In the present study, organohalogen contaminants were analyzed in 113 blood samples from Southern Giant Petrel (Macronectes giganteus) adults and chicks collected in the austral summer of 2011/2012 and 2012/2013 from colonies on Elephant and Livingston Islands, South Shetland, Antarctica. Polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), mirex, dichlorodiphenyltrichloroetane and derivatives (DDTs) and chlordanes were detected in all birds, whereas polybrominated diphenyl ethers (PBDEs) were not detected in any blood samples. No significant differences were found in organochlorine levels between sampling events. Adults exhibited significantly higher levels than chicks, except for PeCB. PCBs, HCB, mirex and DDTs were statistically similar in males and females from Elephant Island. Females on Livingston Island exhibited higher HCB values than males, but no sex differences were found regarding other organochlorines. The similarity in organochlorine levels between sexes in birds with very marked sexual segregation in feeding habits during the breeding season may indicate that significant amounts of contaminants are acquired during migration to lower latitudes, when the diets of males and females are similar. Birds sampled on Livingston Island exhibited significantly lower levels of PCBs, HCB, DDTs, mirex and chlordanes in comparison to those on Elephant Island, which could be the result of distinct foraging patterns between the two colonies. Organochlorine levels were similar between years in birds captured in two consecutive breeding seasons. Blood samples from Southern Giant Petrels adults and chicks proved to be useful for the comparison

  5. 谈合唱的均衡与谐和训练%On the Balance and Coordination Training of Chorus

    Institute of Scientific and Technical Information of China (English)

    石蕾

    2016-01-01

    合唱的均衡与谐和训练涉及很多专业性问题,它包括发声技术、气息控制、音色、音量、音程与和弦、真假声转换、声部的进出等。文章围绕合唱中声部人员及音量比例、力度控制、音色统一、和声连接等方面的问题对合唱声部的均衡与谐和训练进行了梳理与讨论,并提出了个人的见解与应对策略。%The balance and coordination training of chorus involves many professional issues, including sound technology, breath control, timbre, volume, intervals and chords, conversion between falsetto and true voice, voice access. This paper focuses on the voice and volume ratio, strength, tone unity, harmony connection, and analyzes and discusses the balance and coordination training of chorus parts and puts forward some strategies.

  6. Simulation of Resonant Interaction between Energetic Electrons and Whistler-Mode Chorus in the Outer Radiation Belt

    Institute of Scientific and Technical Information of China (English)

    SU Zhen-Peng; ZHENG Hui-Nan

    2008-01-01

    @@ We construct a realistic model to evaluate the chorus wave--particle interaction in the outer radiation belt L = 4.5.This model incorporates a plasmatrough number density model, a field-aligned density model and a realistic wave power and frequency model.We solve the 2D bounce-averaged momentum-pitch-angle Fokker-Planck equation and show that the Whistler-mode chorus can be effective in the acceleration of electrons, and enhance the phase space density for energies of ~1 Me V by a factor from 10 to 103 in about two days, consistent with the observation.We also demonstrate that ignorance of the electron number density variation along field line and magnetic local time in the previous work yields an overestimate of energetic electron phase space density by a factor 5~10 at large pitch-angle after two days, suggesting that a realistic plasma density model is very important to evaluate the evolution of energetic electrons in the outer radiation belt.

  7. Method for direct detection of pitch angle scattering of energetic electrons caused by whistler mode chorus emissions

    Science.gov (United States)

    Kitahara, M.; Katoh, Y.

    2016-06-01

    The Wave-Particle Interaction Analyzer (WPIA), a new instrument proposed by Fukuhara et al. (2009), measures the relative phase angle between the wave magnetic field vector and the velocity vector of each particle and calculates the energy exchange from waves to particles. In this study, we expand its applicability by proposing a method of using the WPIA to directly detect pitch angle scattering of resonant particles by plasma waves by calculating the g values. The g value is defined as the accumulation value of the Lorentz force acting on each particle and indicates the lost momentum of waves. We apply the proposed method to the results of a one-dimensional electron hybrid simulation reproducing the generation of whistler mode chorus emissions around the magnetic equator. Using the wave and particle data obtained at fixed observation points assumed in the simulation system, we conduct a pseudo-observation of the simulation result using the WPIA and analyze the g values. Our analysis yielded significant values indicating the strong pitch angle scattering for electrons in the kinetic energy and pitch angle ranges satisfying the cyclotron resonance condition with the reproduced chorus emissions. The results of this study demonstrate that the proposed method enables us to directly and quantitatively identify the location at which pitch angle scattering occurs in the simulation system and that the method can be applied to the results of space-based observations by the forthcoming Exploration of energization and Radiation in Geospace (ERG) satellite.

  8. Análise química do bambu-gigante (Dendrocalamus giganteus Wall. ex Munro em diferentes idades

    Directory of Open Access Journals (Sweden)

    Nelson Potenciano Marinho

    2012-06-01

    Full Text Available http://dx.doi.org/10.5902/198050985749O bambu é uma planta monocotiledônea de origem tropical, de rápido crescimento, sendo considerado um importante regenerador ambiental devido ao seu sistema radicular. O Dendrocalamus giganteus é popularmente conhecido por bambu-gigante, sendo uma espécie entouceirante de grande porte, cujos colmos podem variar de 24 a 40 metros de altura, com diâmetros entre 10 e 20 cm. Esse trabalho teve como objetivo analisar quimicamente os colmos do bambu-gigante visando fornecer informações sobre a sua composição química nas idades de 2 a 6 anos. Os colmos do bambu foram coletados na área Experimental Agrícola do Departamento de Engenharia Mecânica da UNESP-Bauru, onde é realizado o manejo sistemático de diversas espécies de bambu para fins de pesquisas e divulgação dessa planta. Foram retiradas amostras da base entre bambus com idade de 2 a 6 anos de uma mesma touceira, totalizando 5 amostras, com 2 metros de altura cada, colhidas na lua minguante no mês de março. As análises químicas foram feitas com os entrenós, utilizando as normas e procedimentos da TAPPI. A porcentagem média de extrativos em água quente, extrativos em água fria, extrativos totais e teor de cinzas não apresentaram relação direta com a idade. A maior porcentagem de extrativos em água quente, com valor de 12,04%, extrativos em água fria, com 10,25%, e extrativos totais, com 12,91%, foi observada aos 2 anos de idade. A maior porcentagem de cinzas foi obtida aos três anos, com valores de 1,09%. O teor médio de extrativos em NaOH diminui de 25,72% aos dois anos para 20,17% aos seis anos de idade. O mesmo comportamento foi observado para os extrativos em etanol tolueno, diminuindo de 10,91% para 4,61%. O teor médio de lignina não sofreu influência da idade, variando de 22,66 a 24,11%.

  9. Embryogenic callus formation, growth and regeneration in callus and suspension cultures of Miscanthus x ogiformis Honda 'Giganteus' as affected by proline

    DEFF Research Database (Denmark)

    Holme, Inger Bæksted; Krogstrup, Peter; Hansen, Jürgen

    1997-01-01

    The effects of proline additions to culture systems of Miscanthus x ogiformis Honda Giganteus' were investigated. Proline was added in concentrations of 0, 12.5, 25, 50, 100 or 300 mM to the callus induction and suspension culture media containing either Murashige and Skoog or N6 basal salts and 22...... with Murashige and Skoog salts increased embryogenic callus formation on shoot apices and leaf explants while proline had no effect on embryogenic callus formation in medium with N6 salts. Increased growth with increasing proline concentration was obtained in suspension aggregates grown in medium with N6 salts......, whereas proline only increased growth of suspension aggregates grown in medium with Murashige and Skoog salts at concentrations of 12.5 or 25 mM. A stimulating effect of proline on plant regeneration was observed in short-term cultures of callus as well as in long-term cultures of suspension aggregates...

  10. The coordination of C4 photosynthesis and the CO2-concentrating mechanism in maize and Miscanthus x giganteus in response to transient changes in light quality.

    Science.gov (United States)

    Sun, Wei; Ubierna, Nerea; Ma, Jian-Ying; Walker, Berkley J; Kramer, David M; Cousins, Asaph B

    2014-03-01

    Unequal absorption of photons between photosystems I and II, and between bundle-sheath and mesophyll cells, are likely to affect the efficiency of the CO2-concentrating mechanism in C4 plants. Under steady-state conditions, it is expected that the biochemical distribution of energy (ATP and NADPH) and photosynthetic metabolite concentrations will adjust to maintain the efficiency of C4 photosynthesis through the coordination of the C3 (Calvin-Benson-Bassham) and C4 (CO2 pump) cycles. However, under transient conditions, changes in light quality will likely alter the coordination of the C3 and C4 cycles, influencing rates of CO2 assimilation and decreasing the efficiency of the CO2-concentrating mechanism. To test these hypotheses, we measured leaf gas exchange, leaf discrimination, chlorophyll fluorescence, electrochromatic shift, photosynthetic metabolite pools, and chloroplast movement in maize (Zea mays) and Miscanthus × giganteus following transitional changes in light quality. In both species, the rate of net CO2 assimilation responded quickly to changes in light treatments, with lower rates of net CO2 assimilation under blue light compared with red, green, and blue light, red light, and green light. Under steady state, the efficiency of CO2-concentrating mechanisms was similar; however, transient changes affected the coordination of C3 and C4 cycles in M. giganteus but to a lesser extent in maize. The species differences in the ability to coordinate the activities of C3 and C4 cycles appear to be related to differences in the response of cyclic electron flux around photosystem I and potentially chloroplast rearrangement in response to changes in light quality.

  11. Słowa, wspomnienia i opowieści: poszukiwanie japońskiej tożsamości w Chorus of Mushrooms Hiromi Goto

    OpenAIRE

    2014-01-01

    The novel Chorus of Mushrooms, written by Hiromi Goto, a Japanese-Canadian author, is a peculiar search for identity and the language necessary for expressing that identity. From experiments with words, memories, and stories with which the protagonist attempts to construct her own self, emerges the concept of the scattered, relative Japanese-Canadian identity. The text emphasizes the problem of the dissonance between the ability to speak and the ability to express oneself, and reveals the com...

  12. Instability of whistler mode chorus in space plasma%空间等离子体中哨声波合声模非稳定性

    Institute of Scientific and Technical Information of China (English)

    周庆华; 肖伏良; 唐立军

    2011-01-01

    A systematic study on the instability of whistler mode chorus in space plasma by a Kappa distribution was presented. When the anisotropy or the number density of energetic electrons increases, the wave growth rate increases and the frequency range of positive growth rate is broader. If the temperature of energetic electrons is very low or very high, the interaction between the particles and wave are relatively weak and the growth rate is relatively low. The path-integrated gain of whistler-mode chorus was calculated based on ray trace results and it is found that the lower band chorus has a much higher path-integrated gain than an upper band chorus under the same conditions.%系统分析了Kappa空间等离子体中哨声波合声模的非稳定性.研究发现,高能电子的数密度和温度各向异性越高,哨声波的增长率以及正增长率所对应的频率范围也越大;当电子温度过低或过高时,高能电子与哨声波的相互作用较弱,导致增长率较低;磁纬度越高,传播角越大,增长率越小.利用射线追踪的结果分析了哨声波合声模在传播过程中的增益和衰减过程,计算结果表明,在同等条件下,低频段哨声波合声模的增益远大于高频段哨声波合声模的增益.

  13. The adhesive protein of Choromytilus chorus (Molina, 1782) and Aulacomya ater (Molina, 1782): a proline-rich and a glycine-rich polyphenolic protein.

    Science.gov (United States)

    Burzio, L A; Saéz, C; Pardo, J; Waite, J H; Burzio, L O

    2000-06-15

    The adhesive polyphenolic proteins from Aulacomya ater and Choromytilus chorus with apparent molecular masses of 135000 and 105000, respectively, were digested with trypsin and the peptides produced resolved by reversed phase liquid chromatography. About 5 and 12 major peptides were obtained from the protein of A. ater and C. chorus, respectively. The major peptides were purified by reverse-phase chromatography and the amino acid sequence indicates that both polyphenolic proteins consisted of repeated sequence motifs in their primary structure. The major peptides of A. ater contain seven amino acids corresponding to the consensus sequence AGYGGXK, whereas the tyrosine was always found as 3, 4-dihydroxyphenylalanine (Dopa), the X residue in position 6 was either valine, leucine or isoleucine, and the carboxy terminal was either lysine or hydroxylysine. On the other hand, the major peptides of C. chorus ranged in size from 6 to 21 amino acids and the majority correspond to the consensus sequence AKPSKYPTGYKPPVK. Both proteins differ markedly in the sequence of their tryptic peptides, but they share the common characteristics of other adhesive proteins in having a tandem sequence repeat in their primary structure.

  14. Two new species of Naticidae (Mollusca ,Gastropoda) from the coast of China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Suping

    2008-01-01

    Two new species of Naticidae (Mollusca,Gastropoda) collected from the coast of China are described:Cryptonaitca huanghaien- sis sp.nov.and Sinum vittatum sp.nov.The morphological characteristics between the new species were described and the relat- ed information was provided.The similarities and differences between the new species and related species were also compared and discussed.The new species Cryptonaitca huanghaiensis differed from Cryptonaitca hirasei and Cryptonaitca andoi in outer shape, operculum and radula.The new species Sinum vittatum is similar to Sinum japonicum (Lischke,1869),but the shell of the for- mer is flat-elliptical in shape,spire very small,slightly convex.While the latter is flat-globular in shape,apex light brown in col- or,without a brown band on the body whorl.The comparison results revealed that Cryptonaitca huanghaiensis and Sinum vittatum were two new species from the coast of China.Specimens studied were obtained from collections in the Marine Biological Museum, Chinese Academy of Sciences.

  15. With a little help from DNA barcoding: investigating the diversity of Gastropoda from the Portuguese coast.

    Science.gov (United States)

    Borges, Luísa M S; Hollatz, Claudia; Lobo, Jorge; Cunha, Ana M; Vilela, Ana P; Calado, Gonçalo; Coelho, Rita; Costa, Ana C; Ferreira, Maria S G; Costa, Maria H; Costa, Filipe O

    2016-02-15

    The Gastropoda is one of the best studied classes of marine invertebrates. Yet, most species have been delimited based on morphology only. The application of DNA barcodes has shown to be greatly useful to help delimiting species. Therefore, sequences of the cytochrome c oxidase I gene from 108 specimens of 34 morpho-species were used to investigate the molecular diversity within the gastropods from the Portuguese coast. To the above dataset, we added available COI-5P sequences of taxonomically close species, in a total of 58 morpho-species examined. There was a good match between ours and sequences from independent studies, in public repositories. We found 32 concordant (91.4%) out of the 35 Barcode Index Numbers (BINs) generated from our sequences. The application of a ranking system to the barcodes yield over 70% with top taxonomic congruence, while 14.2% of the species barcodes had insufficient data. In the majority of the cases, there was a good concordance between morphological identification and DNA barcodes. Nonetheless, the discordance between morphological and molecular data is a reminder that even the comparatively well-known European marine gastropods can benefit from being probed using the DNA barcode approach. Discordant cases should be reviewed with more integrative studies.

  16. 18S ribosomal DNA sequences provide insight into the phylogeny of patellogastropod limpets (Mollusca: Gastropoda).

    Science.gov (United States)

    Yoon, Sook Hee; Kim, Won

    2007-02-28

    To investigate the phylogeny of Patellogastropoda, the complete 18S rDNA sequences of nine patellogastropod limpets Cymbula canescens (Gmelin, 1791), Helcion dunkeri (Krauss, 1848), Patella rustica Linnaeus, 1758, Cellana toreuma (Reeve, 1855), Cellana nigrolineata (Reeve, 1854), Nacella magellanica Gmelin, 1791, Nipponacmea concinna (Lischke, 1870), Niveotectura pallida (Gould, 1859), and Lottia dorsuosa Gould, 1859 were determined. These sequences were then analyzed along with the published 18S rDNA sequences of 35 gastropods, one bivalve, and one chiton species. Phylogenetic trees were constructed by maximum parsimony, maximum likelihood, and Bayesian inference. The results of our 18S rDNA sequence analysis strongly support the monophyly of Patellogastropoda and the existence of three subgroups. Of these, two subgroups, the Patelloidea and Acmaeoidea, are closely related, with branching patterns that can be summarized as [(Cymbula + Helcion) + Patella] and [(Nipponacmea + Lottia) + Niveotectura]. The remaining subgroup, Nacelloidea, emerges as basal and paraphyletic, while its genus Cellana is monophyletic. Our analysis also indicates that the Patellogastropoda have a sister relationship with the order Cocculiniformia within the Gastropoda.

  17. Volutidae (Mollusca: Gastropoda) of the Lakhra Formation (Earliest Eocene, Sindh, Pakistan): systematics, biostratigraphy and paleobiogeography.

    Science.gov (United States)

    Merle, Didier; Pacaud, Jean-Michel; Métais, Grégoire; Bartolini, Annachiara; Lashari, Rafiq A; Brohi, Imdad A; Solangi, Sarfraz H; Marivaux, Laurent; Welcomme, Jean-Loup

    2014-06-27

    The paleobiodiversity of the Volutidae (Mollusca: Gastropoda) of the Ranikot Group (Sindh, Pakistan) and particularly of the Lakhra Formation (SBZ 5 biozone, Earliest Eocene), is reconsidered on the basis of new material collected during recent field trips. Ten new species are described (Mitreola brohii sp. nov., Lyrischapa vredenburgi sp. nov., L. brevispira sp. nov., Athleta (Volutopupa) citharopsis sp. nov., A. (Volutocorbis) lasharii sp. nov., Volutilithes welcommei sp. nov., V. sindhiensis sp. nov., Pseudaulicina coxi sp. nov., Sindhiluta lakhraensis sp. nov. and Pakiluta solangii sp. nov.) and one species is in open nomenclature (Lyria sp.). Three new genera are described: Lyriopsis gen. nov. [Volutinae, ?Lyriini, type species: Lyriopsis cossmanni (Vredenburg, 1923)], Sindhiluta gen. nov. [Volutilithinae, type species: Sindhiluta lakhraensis n. sp.] and Pakiluta gen. nov. [?Volutodermatinae, type species: Pakiluta solangii n. sp.]. Two new combinations are proposed: Lyriopsis cossmanni (Vredenburg, 1923) comb. nov. and Athleta (Volutopupa) intercrenatus (Cossmann & Pissarro, 1909) comb. nov. Lectotypes are designated for Lyria cossmanni Vredenburg, 1923, L. feddeni Vredenburg, 1923, Volutospina noetlingi Cossmann & Pissarro, 1909, V. intercrenata Cossmann & Pissarro, 1909 and Athleta (Volutocorbis) victoriae Vredenburg, 1923. With 21 species, this volutid fauna is the most diverse recorded from the Tethys Ocean during Earliest Eocene time. The assemblage is characterized by a strong turnover marked by regional speciation and the appearance of many western Tethyan invaders. Although at the species level, the assemblage documents a strong provincialism, at the genus level, the high number of shared genera between Eastern Tethyan and Old World Tethyan realms begins a phase of long-term homogeneity of volutid assemblages from the Tethyan paleobiogeographic province.

  18. Use of clearance rate in Choromytilus chorus (Bivalvia: Mytilidae) as a non-destructive biomarker of aquatic pollution El uso de la tasa de aclaramiento en Choromytilus chorus (Bivalvia: Mytilidae) como biomarcador no destructivo de la polución acuática

    OpenAIRE

    BEATRIZ TORO; Jorge M Navarro; HERNÁN PALMA-FLEMING

    2003-01-01

    Reduction in clearance rate was observed in the mussel Choromytilus chorus in relation to the degree of environmental pollution. Three sampling sites included the polluted San Vicente Bay, middling polluted Corral Bay, and weakly polluted Yaldad Bay in southern Chile. Pollution levels were estimated by quantitative analysis of polynuclear aromatic hydrocarbons (PAHs) in mussel tissue from the three sites. Mussels from San Vicente showed lowest clearance rates and highest PAHs levels in both s...

  19. 论合唱教育中的情商体现与培养%Chorus education and training reflect EQ

    Institute of Scientific and Technical Information of China (English)

    华夏

    2015-01-01

    合唱艺术自西方传入中国虽然只有一百多年的历史,但合唱教育发展至今已成为中国音乐教育中的一项重要内容,合唱课程的设置、合唱团体的培养促进了合唱艺术的发展。合唱教育除了提高学生的音乐素养还具有很强的教化作用,在此,笔者认为合唱教育不仅能培养人的团队精神及合作意识,还能有效提高人的情商。文章着重于合唱中的情商体现与培养,并论述情商培养的社会意义。%Chorus from the west into China, although only a hundred years of history, but the development of education has become a chorus of music education in China is an important element, setting, training courses choir choral groups promoted the development of choral art. Choral music education in addition to improving students' literacy also has a strong role of education in this, I believe that not only choral education awareness teamwork and cooperation of people, but also effectively improve people's emotional intelligence. The article focuses on the chorus and EQ reflects culture, and discusses the social significance of EQ training.

  20. How to Let the Chorus Teaching Integrate into the Course of Music Appreciation%如何将合唱教学融入音乐欣赏课

    Institute of Scientific and Technical Information of China (English)

    谢敏

    2014-01-01

    对于青少年来说,音乐教育是不可缺少的一门课程,而合唱是音乐教育中的培养学生感性认识的重要课程,并提高学生的文化素质。合唱是一种团体行为,在演唱过程中,不仅能通过音乐抒发情感,凝聚情感,还能使学生互相接触、学习、合作等。合唱教学被一些音乐教师当成是一种难以掌握的教学环节。除了环境、师生等客观因素外,科学的教学方法也是帮助突破课堂上许多瓶颈的重要一环。%For teenagers,music education is an indispensable course,while the chorus is an important course for students perceptual knowledge training in music education,and improve the students’ cultural quality. The chorus is a kind of group behavior,during the song,not only through the music to express of emotion,emotional cohesion,but also can enable students to contact each other,learning,cooperation etc. Chorus teaching by some music teachers as a difficult teaching. In addition to the environment,the teachers and students and other objective factors,scientific teaching method is to help break through the classroom many bottleneck is important one annulus.

  1. A retrospective study of Babesia macropus associated with morbidity and mortality in eastern grey kangaroos (Macropus giganteus and agile wallabies (Macropus agilis

    Directory of Open Access Journals (Sweden)

    Shannon L. Donahoe

    2015-08-01

    Full Text Available This is a retrospective study of 38 cases of infection by Babesia macropus, associated with a syndrome of anaemia and debility in hand-reared or free-ranging juvenile eastern grey kangaroos (Macropus giganteus from coastal New South Wales and south-eastern Queensland between 1995 and 2013. Infection with B. macropus is recorded for the first time in agile wallabies (Macropus agilis from far north Queensland. Animals in which B. macropus infection was considered to be the primary cause of morbidity had marked anaemia, lethargy and neurological signs, and often died. In these cases, parasitised erythrocytes were few or undetectable in peripheral blood samples but were sequestered in large numbers within small vessels of visceral organs, particularly in the kidney and brain, associated with distinctive clusters of extraerythrocytic organisms. Initial identification of this piroplasm in peripheral blood smears and in tissue impression smears and histological sections was confirmed using transmission electron microscopy and molecular analysis. Samples of kidney, brain or blood were tested using PCR and DNA sequencing of the 18S ribosomal RNA and heat shock protein 70 gene using primers specific for piroplasms. The piroplasm detected in these samples had 100% sequence identity in the 18S rRNA region with the recently described Babesia macropus in two eastern grey kangaroos from New South Wales and Queensland, and a high degree of similarity to an unnamed Babesia sp. recently detected in three woylies (Bettongia penicillata ogilbyi in Western Australia.

  2. Effects of hydroperiod duration on survival, developmental rate, and size at metamorphosis in boreal chorus frog tadpoles (Pseudacris maculata)

    Science.gov (United States)

    Amburgey, Staci; Funk, W. Chris; Murphy, Melanie; Muths, Erin

    2012-01-01

    Understanding the relationship between climate-driven habitat conditions and survival is key to preserving biodiversity in the face of rapid climate change. Hydroperiod—the length of time water is in a wetland—is a critical limiting habitat variable for amphibians as larvae must metamorphose before ponds dry. Changes in precipitation and temperature patterns are affecting hydroperiod globally, but the impact of these changes on amphibian persistence is poorly understood. We studied the responses of Boreal Chorus Frog (Pseudacris maculata) tadpoles to simulated hydroperiods (i.e., water level reductions) in the laboratory using individuals collected from ponds spanning a range of natural hydroperiods (Colorado Front Range, USA). To assess the effects of experimental hydroperiod reduction, we measured mortality, time to metamorphosis, and size at metamorphosis. We found that tadpoles grew at rates reflecting the hydroperiods of their native ponds, regardless of experimental treatment. Tadpoles from permanent ponds metamorphosed faster than those from ephemeral ponds across all experimental treatments, a pattern which may represent a predation selection gradient or countergradient variation in developmental rates. Size at metamorphosis did not vary across experimental treatments. Mortality was low overall but varied with pond of origin. Our results suggest that adaptation to local hydroperiod and/or predation and temperature conditions is important in P. maculata. Moreover, the lack of a plastic response to reduced hydroperiods suggests that P. maculata may not be able to metamorphose quickly enough to escape drying ponds. These results have important implications for amphibian persistence in ponds predicted to dry more quickly due to rapid climate change.

  3. Gastropoda-Bivalvia Fauna And Neogene-Quaternary Stratigraphy of the Southwest of Dardanelles (Çanakkale-NWAnatolia)

    Science.gov (United States)

    Kapan, Sevinç; Kabasakal, Sinem

    2016-04-01

    Gastropoda-Bivalvia Fauna And Neogene-Quaternary Stratigraphy of the Southwest of Dardanelles (Çanakkale-NWAnatolia) Sevinç KAPAN, Sinem KABASAKAL, Çanakkale Onsekiz Mart University, Engineering Faculty, Geological Engineering Department sevinckapan_yesilyurt@hotmail.com In this study, paleontology and stratigraphy of Neogene and Quaternary units around south of the Dardanelles have been examined using Gastropoda and Bivalvia fauna. In the investigation area, the base of the sediments that belongs to Neogene, consist of the volcanics which are formed with basalts, andesites and tuff. Neogene begins unconformity with basal conglomerate which are formed with basalt and tuff gravels. The measurable thickness of the Neogene sediments is approximately 200meters in total. First fossiliferius level which consist of Lymnocardium (Euxinicardium) nobile Sabba has showed similarities with the Pontian (Late Miocene) fauna of the Eastern Paratethys. The existence of Melanopsis and Psidium species indicate that the basin has been brackish water feeding by fresh water in the Early Pliocene. Theodoxus fluviatilis (Linne), Theodoxus (Calvertia) aff. imbricata Brusina, Theodoxus (Calvertia) licherdopoli scriptus (Stefanescu), Viviparus mammatus (Stefanescu), Valvata (Valavata) sulekiana Brusina, Valvata (Cincinna) crusitensis Fontannes, Hydrobia cf grandis Cobalcescu, Hydrobia ventrosa Monfort, Melanopsis (Melanopsis) cf. bergeroni Stefanescu, , Melanopsis (Melanopsis) sandbergeri rumana Tournouer, Melanopsis (Canthidomus) hybostoma anili Taner, Melanopsis (Canthidomus) hybostoma amaradica Fontannes, Melanopsis (Canthidomus) lanceolata Neumayr, Amphimelania fossariformis (Tournouer), Melanoides tuberculata monolithica (Bukowski), Radix (Radix) peregra (Müller), Planorbarius thiollierei (Michaud), Potamida (Potamida) craiovensis craiovensis (Tournouer), Potamida (Potamida) berbestiensis (Fontannes), Unio pristinus davilai Porumbaru, Unio subexquisitus Jatzko, Anadonta zmaji

  4. Izolované populace praménky Bythinella austriaca (Frauenfeld, 1857 (Gastropoda: Hydrobiidae v okolí Prahy

    Directory of Open Access Journals (Sweden)

    Luboš Beran

    2010-03-01

    Full Text Available This paper completes the knowledge of an occurrence of Bythinella austriaca (Frauenfeld, 1857 (Gastropoda: Hydrobiidae in surroundings of Prague – capital of the Czech Republic. However, this species is not rare in the eastern part of the Czech Republic, sites on north-western otskirts of Prague are isolated far from the main distribution area. Altogether, 63 sites potentially suitable for B. austriaca were investigated in this area, and occurrence of this species was confirmed in 11 of them. B. austriaca was found in springs, rivulets and small brooks, more numerous populations were found in springs. Historical occurrence data in this area were compared with results of research done in 2003, 2006 and 2010. Actual situation of this species in Prague surroundings is problematic and survival of some populations is not guaranteed.

  5. A new freshwater snail genus (Hydrobiidae, Gastropoda from Montenegro, with a discussion on gastropod diversity and endemism in Skadar Lake

    Directory of Open Access Journals (Sweden)

    Vladimir Pesic

    2013-03-01

    Full Text Available Karucia sublacustrina a new species of freshwater snails (Hydrobiidae, Gastropoda is described based on material collected from Skadar Lake (Montenegro, Albania. The new species belongs to monotypic genus Karucia gen. n. The shell morphology and body shape of the new genus resembles Radomaniola Szarowska, 2006 and Grossuana Radoman, 1973, from which it differs in the larger shells with relatively slim and a slightly, but clearly shouldered body whorl. The number of gastropods from Skadar Lake basin tallies now 50 species. The adjusted rate of gastropod endemicity for Skadar Lake basin is estimated to be 38%. By compiling faunal and taxonomic data we also aim to provide information of relevance as to conservation efforts.

  6. Some Thinkings on the Development of China's Chorus%对我国合唱事业发展问题的若干思考

    Institute of Scientific and Technical Information of China (English)

    王丽莎

    2011-01-01

    suggsetions on the development of Chinese chorus are offered in this paper,which are: vocal coaches should be ambitious and responsible persons with a sense of mission,exploring and innovative spirits;The development of China's chorus should begin with the children.Emphases should be laid on the music instruction in preschools,primary and high schools;The system of choral education with Chinese characteristics should be established;vocal coaches should keep up with the trend of the most advanced choral education in the world.%对我国合唱事业的发展问题进行了如下思考:其一,要做有思想、有抱负、有使命感、勇探索、能创新的合唱事业的工作者;其二,中国合唱事业的发展要从娃娃抓起,注重中、小、幼学校的基础音乐教育;第三,构建有中国特色的合唱教育体系;第四,中小学音乐教育应适应当代世界音乐教育发展的历史潮流;第五,要学习借鉴世界先进的合唱艺术教育的理念与优秀成果。

  7. Sperm competition and the evolution of precopulatory weapons: Testis size and amplexus position, but not arm strength, affect fertilization success in a chorusing frog.

    Science.gov (United States)

    Buzatto, Bruno A; Thyer, Evan M; Roberts, J Dale; Simmons, Leigh W

    2017-02-01

    Trade-offs between pre- and postcopulatory traits influence their evolution, and male expenditure on such traits is predicted to depend on the number of competitors, the benefits from investing in weapons, and the risk and intensity of sperm competition. Males of the chorusing frog Crinia georgiana use their arms as weapons in contest competition. Previously, we showed that increased numbers of rivals elevated the risk and intensity of sperm competition due to multimale amplexus, and caused a reversal in the direction of precopulatory selection on arm girth. Here, we focused on the factors affecting postcopulatory fertilization success during group spawning, using paternity data from natural choruses. Competitive fertilization success depended on the time spent amplexed and amplexus position. Relative testes size but not arm girth, contributed to fertilization success, but the effect of testes size depended on amplexus position. Our findings offer within species empirical support for recent sperm competition models that incorporate precopulatory male-male competition, and show why an understanding of the evolution of animal weapons requires a consideration of both pre- and postcopulatory episodes of sexual selection.

  8. Final Report DE-SC0006634. Quantifying phenotypic and genetic diversity of Miscanthus sinensis as a resource for knowledge-based improvement of M. ×giganteus (M. sinensis × M. sacchariflorus)

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, Erik [Univ. of Illinois, Urbana, IL (United States)

    2016-02-08

    Miscanthus is especially attractive as a bioenergy crop for temperate environments because it produces high yields, needs few inputs, and grows well during the cool weather of early spring and late fall when few warm-season grasses can. However, Miscanthus feedstock production for the emerging U.S. bioenergy industry and for existing demand in Europe is based on a single sterile, vegetatively propagated variety of M. ×giganteus. M. ×giganteus is an interspecific hybrid of the parental species M. sinensis and M. sacchariflorus. Prior to the current study, little information existed about the genetic diversity and breeding potential of either M. ×giganteus parental species. In the current project, we studied more than 600 accessions of M. sinensis from throughout its native range in China, Japan, and Korea, in addition to ornamental cultivars and U.S. naturalized populations. Using thousands of DNA markers, we identified seven geographically distinct genetic groups of M. sinensis. Notably, we found that the ornamental cultivars and U.S. naturalized populations were derived from only a subset of the Southern Japan group, indicating that our study greatly increased the genetic diversity available for breeding new biomass cultivars. Additionally, this new understanding of M. sinensis population structure could be used to predict which crosses may produce progeny with the greatest hybrid vigor. Replicated field trials were also established at multiple locations in North America and Asia. Data on traits of importance for biomass productivity, such as flowering time, yield and height, were taken. Analyses of the phenotypic data from the field trials along with the DNA markers allowed us to identify many marker-trait associations. These results will enable marker-assisted breeding, which will allow selection at the seedling stage rather than waiting two to three years to obtain phenotypic data. Thus, this study is expected to greatly increase the efficiency of breeding

  9. Hybridization and back-crossing in giant petrels (Macronectes giganteus and M. halli) at Bird Island, South Georgia, and a summary of hybridization in seabirds.

    Science.gov (United States)

    Brown, Ruth M; Techow, N M S Mareile; Wood, Andrew G; Phillips, Richard A

    2015-01-01

    Hybridization in natural populations provides an opportunity to study the evolutionary processes that shape divergence and genetic isolation of species. The emergence of pre-mating barriers is often the precursor to complete reproductive isolation. However, in recently diverged species, pre-mating barriers may be incomplete, leading to hybridization between seemingly distinct taxa. Here we report results of a long-term study at Bird Island, South Georgia, of the extent of hybridization, mate fidelity, timing of breeding and breeding success in mixed and conspecific pairs of the sibling species, Macronectes halli (northern giant petrel) and M. giganteus (southern giant petrel). The proportion of mixed-species pairs varied annually from 0.4-2.4% (mean of 1.5%), and showed no linear trend with time. Mean laying date in mixed-species pairs tended to be later than in northern giant petrel, and always earlier than in southern giant petrel pairs, and their breeding success (15.6%) was lower than that of conspecific pairs. By comparison, mixed-species pairs at both Marion and Macquarie islands always failed before hatching. Histories of birds in mixed-species pairs at Bird Island were variable; some bred previously or subsequently with a conspecific partner, others subsequently with a different allospecific partner, and some mixed-species pairs remained together for multiple seasons. We also report the first verified back-crossing of a hybrid giant petrel with a female northern giant petrel. We discuss the potential causes and evolutionary consequences of hybridization and back-crossing in giant petrels and summarize the incidence of back-crossing in other seabird species.

  10. Phylogeny in defining model plants for lignocellulosic ethanol production: a comparative study of Brachypodium distachyon, wheat, maize, and Miscanthus x giganteus leaf and stem biomass.

    Science.gov (United States)

    Meineke, Till; Manisseri, Chithra; Voigt, Christian A

    2014-01-01

    The production of ethanol from pretreated plant biomass during fermentation is a strategy to mitigate climate change by substituting fossil fuels. However, biomass conversion is mainly limited by the recalcitrant nature of the plant cell wall. To overcome recalcitrance, the optimization of the plant cell wall for subsequent processing is a promising approach. Based on their phylogenetic proximity to existing and emerging energy crops, model plants have been proposed to study bioenergy-related cell wall biochemistry. One example is Brachypodium distachyon, which has been considered as a general model plant for cell wall analysis in grasses. To test whether relative phylogenetic proximity would be sufficient to qualify as a model plant not only for cell wall composition but also for the complete process leading to bioethanol production, we compared the processing of leaf and stem biomass from the C3 grasses B. distachyon and Triticum aestivum (wheat) with the C4 grasses Zea mays (maize) and Miscanthus x giganteus, a perennial energy crop. Lambda scanning with a confocal laser-scanning microscope allowed a rapid qualitative analysis of biomass saccharification. A maximum of 108-117 mg ethanol·g(-1) dry biomass was yielded from thermo-chemically and enzymatically pretreated stem biomass of the tested plant species. Principal component analysis revealed that a relatively strong correlation between similarities in lignocellulosic ethanol production and phylogenetic relation was only given for stem and leaf biomass of the two tested C4 grasses. Our results suggest that suitability of B. distachyon as a model plant for biomass conversion of energy crops has to be specifically tested based on applied processing parameters and biomass tissue type.

  11. Symphonic Cantata «In the Temple of Golden Dreams» by Arthur Lourie for Mixed Chorus a cappella (1919: Innovation in the Field of Musical Language

    Directory of Open Access Journals (Sweden)

    Zaytseva Marina

    2017-01-01

    Full Text Available The article scientifically proves the importance of choral genres in the works by Arthur Lourie. The features of composition and the musical language of the symphonic cantata «In the Temple of Golden Dreams» by Arthur Lourie are identified. It is proved that the trends of symbolism and avant-garde affected the formation of the logic of intonation development , composite and harmonic solutions of the cantata. It is justified that the composer’s experiments in the fields of harmonic language, metroritm, texture, timbre brilliance largely anticipate the trends of the world music development. On the basis of the «In the Temple of Golden Dreams» symphonic cantata for mixed chorus a cappella A. Lurie, innovative methods of convergence of expressive possibilities of symphonic and choral scores, aimed at strengthening the capabilities of color and expressive choral sound are identified.

  12. 我国小学音乐合唱教学现状与问题研究%A Study on the Present Situation and Problems of Primary School Music Chorus Teaching in China

    Institute of Scientific and Technical Information of China (English)

    孙明明

    2016-01-01

    童声合唱一直以来就得到了人们的喜爱,那如天籁的声音是乐器无法比肩的。童声合唱在小学音乐教育中更是发挥越来越重要的作用,童声合唱除了对于孩子们的歌唱能力有积极的影响外,对于孩子们的思想品德、思维方式、想象力、团队意识、协作能力等等也有着潜移默化的影响。本文以小学音乐合唱教学为基础,对童声合唱历史、现状做出简单陈述,并就现如今我国小学音乐合唱教学问题进行分析,最后提出部分提高我国小学音乐合唱教学质量提高的方法及解决措施,以期能够对小学音乐合唱教学实践提供更多的理论依据,并使小学音乐合唱教学更加完善。%Children's chorus has obtained people's favorite, it sounds like the voice of the instrument is unable to shoulder. Children's chorus in music education in primary schools is to play a more and more important role, children's chorus in addition to have a positive impact on children's singing ability, for the children of the ideology and moral character, mode of thinking, imagination, team consciousness, cooperation ability and so on also has a silent influence of creep. This paper to primary school music teaching of chorus based, for children's chorus history, current situation make simple statements, and now my elementary school chorus teaching problems are analyzed. Finally, it puts forward part to improve the methods of improving the teaching quality of primary school choral music in China and measures to solve, in order to provide more theoretical basis for primary school choral music teaching practice, and the primary school choral music teaching to be more perfect.

  13. Biochemical profile of Achatina fulica (Mollusca: Gastropoda) after infection by different parasitic loads of Angiostrongylus cantonensis (Nematoda, Metastrongylidae).

    Science.gov (United States)

    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Amaral, Ludimila Santos; Mota, Esther Maria; Maldonado Júnior, Arnaldo; Pinheiro, Jairo; Garcia, Juberlan

    2015-01-01

    The effect of experimental infection by different parasitic loads of Angiostrongylus cantonensis (Nematode, Metastrongylidae) on the activities of the aminotransferases and concentration of total proteins, uric acid and urea in the hemolymph of Achatina fulica (Mollusca, Gastropoda) were investigated. There was a significant decrease in the concentration of total proteins in the exposed snails to 5000 or more larvae. This change was accompanied by an increase in the concentrations of urea and uric acid in the hemolymph, suggesting a higher rate of deamination of the amino acids. Besides this, variations in the activities of the aminotransferases were also observed, with the highest values recorded in the groups exposed to greater parasite load. These results suggest an increase in the use of total proteins, since there was increased formation of nitrogenous catabolites, in conformity with an increase in the aminotransferase activities. Infection was verified by the fact that L3 larvae recovered from the snails was proportion to the exposure dose of L1 larvae. Histopathological results also indicated presence of an inflammatory cell infiltrate, favoring an increase of both transaminases.

  14. Assessing metal contamination from construction and demolition (C&D) waste used to infill wetlands: using Deroceras reticulatum (Mollusca: Gastropoda).

    Science.gov (United States)

    Staunton, John A; Mc Donnell, Rory J; Gormally, Michael J; Williams, Chris D; Henry, Tiernan; Morrison, Liam

    2014-11-01

    Large quantities of construction and demolition waste (C&D) are produced globally every year, with little known about potential environmental impacts. In the present study, the slug, Deroceras reticulatum (Mollusca: Gastropoda) was used as the first biomonitor of metals (Ag, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Ti, Tl, V and Zn) on wetlands post infilling with construction and demolition (C&D) waste. The bioaccumulation of As, Ba, Cd, Co, Sb, Se and Tl were found to be significantly elevated in slugs collected on C&D waste when compared to unimproved pastures (control sites), while Mo, Se and Sr had significantly higher concentrations in slugs collected on C&D waste when compared to known contaminated sites (mining locations), indicating the potential hazardous nature of C&D waste to biota. Identifying exact sources for these metals within the waste can be problematic, due to its heterogenic nature. Biomonitors are a useful tool for future monitoring and impact studies, facilitating policy makers and regulations in other countries regarding C&D waste infill. In addition, improving separation of C&D waste to allow increased reuse and recycling is likely to be effective in reducing the volume of waste being used as infill, subsequently decreasing potential metal contamination.

  15. Dos nuevas localizaciones para España de Bulinus truncatus (Audouin, 1827 (Gastropoda, Planorbidae, hospedador intermediario de Schistosomiasis urinaria

    Directory of Open Access Journals (Sweden)

    Martínez-Ortí, A.

    2015-07-01

    Full Text Available Two new locations in Spain of Bulinus truncatus (Audouin, 1827 (Gastropoda, Planorbidae, intermediate host of urinary Schistosomiasis Two new populations of the planorbid snail species Bulinus truncatus were found in Spain in 2014. The first consisted of shells only, found in the lagoon of Villena (province of Alicante, which had dried up at the beginning of the 19th century. This finding is of important biogeographic interest because it links the presence of this species in northern Catalonia with its detection in southern Andalucia as this species had not been found previously in the regions of Murcia or Valencia. The second population was found in El Ejido (province of Almeria, and thousands of living specimens were found here. This allowed a complete shell characterisation and molecular assessment by means of sequencing the cox1 gene of the mitochondrial DNA genome, which showed 100% homology with sequences of other populations of the same snail species available in the GenBank. The finding of B. truncatus in Almeria is of additional value given the applied importance of this planorbid species as a vector of urinary Schistosomiasis, thus representing a risk of introduction and autochthonous transmission of the disease in Spain, as has occurred in other southern European countries in the past and recently.

  16. Teaching. Quality of Vocal Music in Colleges of China from Chorus Competition%从合唱比赛看我国高校的声乐教学质量

    Institute of Scientific and Technical Information of China (English)

    耿耀

    2012-01-01

    分析了我国合唱比赛中存在的问题。指出在音乐教学中,为求音色统一而存在声音观念上的误区,为求新颖别致而存在强调表现的误区。提出高质量的声乐教学是合唱团员良好音乐素养的保障。%The problems existing in chorus competition of China are analyzed. The misunderstandings in concept of voice for unified timbre, and focusing on performance to be unique in teaching of vocal music are pointed out. It is proposed that, the high-quality vocal teaching is the protection of the good music literacy of the members of chorus.

  17. The Artistic Performance Characteristics of the Mixed Chorus "Initiating a New Era"%略论地方本科院校历史学专业教学改革

    Institute of Scientific and Technical Information of China (English)

    钟玉发

    2012-01-01

    The mixed chorus "Initiating a New Era" is the representative works of Professor Ping Liming, a Chinese conductor and composer. It was awarded the prize "Five-One Projects" in the spiritual civilization of Guangdong Province in 2007. This chorus is felicitously structured, breaking through the traditional musical form. It combines Chinese and western mode and tonality, arranging voice part based on voice features, which provides large room for the development of refined lyrics. The mixed chorus "Initiating a New Era" has become an out- standing chorus works in China after being polished for many times.%21世纪以来,随着高等教育乃至初等教育改革日益向纵深方向发展,古老的历史学科面临重重压力与挑战。就本科院校的历史学专业教学而言,主要存在着“两通”比重过大、选修课门类太少、与中学历史教学实际需求联系不紧密以及培养学生能力的课程欠缺等。进一步改革的思路是,加强教师队伍自身建设和课程理念现代化,教学内容上压缩“两通”、增设选修课、突出师范特色并保持师范性与学术性的统一以及改进实践教学环节、提高学生的中学课堂教学和论文写作能力等。

  18. 论混声合唱《把崭新的世纪开创》的艺术特征%The Artistic Performance Characteristics of the Mixed Chorus "Initiating a New Era"

    Institute of Scientific and Technical Information of China (English)

    徐文博

    2012-01-01

    The mixed chorus "Initiating a New Era" is the representative works ot eroiessor ring blIIllIlg, il Chinese conductor and composer. It was awarded the prize "Five-One Projects" in the spiritual civilization of Guangdong Province in 2007. This chorus is felicitously structured, breaking through the traditional musical form. It combines Chinese and western mode and tonality, arranging voice part based on voice features, which provides large room for the development of refined lyrics. The mixed chorus "Initiating a New Era" has become an out- standing chorus works in China after being polished for many times.%混声合唱《把崭新的世纪开创》是作曲家平黎明教授的代表作品,2007年获得广东省第六届精神文明建设“五个一工程”奖。这首作品在结构上巧妙构建,突破了传统理论上的曲式结构;在调式调性上中西并用,巧妙地使用人声特点安排声部布局,为精炼的歌词拓展了广阔的发展空间;混声合唱《把崭新的世纪开创》在经过多次的锤炼后,已经成为一首优秀的合唱作品。

  19. Percepção da voz e saúde vocal em idosos coralistas Perception of voice and vocal health in aged chorus members

    Directory of Open Access Journals (Sweden)

    Regina Zanella Penteado

    2010-04-01

    Full Text Available OBJETIVO: analisar a percepção da voz e de suas alterações e os cuidados de saúde vocal de idosos coralistas. MÉTODOS: são sujeitos 10 idosos (seis mulheres e quatro homens do Coral Evangélico de Piracicaba (SP. Foi aplicado o questionário Qualidade de vida e voz (QVV, realizada entrevista aberta sobre o que acham da voz, queixas e cuidados e a avaliação vocal. Procedimentos de análise: análise de Conteúdo/análise temática, análise descritiva das questões, cálculo do escore global do QVV e análise perceptivo-auditiva fonoaudiológica por meio da escala GRBASI e avaliação dos parâmetros vocais. RESULTADOS: nove idosos avaliaram a voz como boa e apresentaram imagem vocal positiva, com escore médio de 96,5 pontos no QVV. Apesar disto, manifestaram dificuldades relacionadas com a respiração, articulação, modulação, além de alterações vocais em grau leve (rugosidade e soprosidade na avaliação fonoaudiológica. Os cuidados com a voz se mostraram insuficientes para a promoção da saúde vocal. CONCLUSÃO: o grupo de idosos coralistas pesquisado, apesar de não ter queixas e estar satisfeito com a voz, apresenta dificuldades relacionadas aos cuidados de saúde vocal, à percepção da voz e do processo saúde-doença vocal bem como parâmetros alterados.PURPOSE: to analyze the perception of voice, its alterations and vocal health care in aged chorus members. METHODS: subjects are ten (six woman and four man aged members of Piracicaba's Evangelic Chorus. QVV (Quality of life and voice questionnaire was applied through an open interview on voice, complaints and cares; and vocal evaluation. Analysis procedures: Content/thematic analysis, descriptive analysis of the questions, calculating the QVV global score, and perceptual auditory analysis using GRBASI scale and evaluation of vocal parameters. RESULTS: nine subjects evaluated their own voice as good and showed a positive vocal image, with a mean score of 96.5 points in

  20. Nyctemeral variations of magnesium intake in the calcitic layer of a Chilean mollusk shell ( Concholepas concholepas, Gastropoda)

    Science.gov (United States)

    Lazareth, Claire E.; Guzman, Nury; Poitrasson, Franck; Candaudap, Frederic; Ortlieb, Luc

    2007-11-01

    Mollusk shells are increasingly used as records of past environmental conditions, particularly for sea-surface temperature (SST) reconstructions. Many recent studies tackled SST (and/or sea-surface salinity) tracers through variations in the elementary (Mg and Sr) or stable isotope (δ 18O) composition within mollusk shells. But such attempts, which sometimes include calibration studies on modern specimens, are not always conclusive. We present here a series of Mg and Sr analyses in the calcitic layer of Concholepas concholepas (Muricidae, Gastropoda) with a very high time-resolution on a time window covering about 1 and a half month of shell formation, performed by Laser Ablation Inductively-Coupled Plasma Mass Spectrometry (LA-ICP-MS) and electron probe micro-analysis (EPMA). The selected specimen of this common Chilean gastropod was grown under controlled environmental conditions and precise weekly time-marks were imprinted in the shell with calcein staining. Strontium variations in the shell are too limited to be interpreted in terms of environmental parameter changes. In contrast, Mg incorporation into the shell and growth rate appear to change systematically between night and day. During the day, Mg is incorporated at a higher rate than at night and this intake seems positively correlated with water temperature. The nightly reduced Mg incorporation is seemingly related to metabolically controlled processes, formation of organic-rich shell increments and nocturnal feeding activity of the animals. The nyctemeral Mg changes in the C. concholepas shell revealed in this study might explain at least part of the discrepancies observed in previous studies on the use of Mg as a SST proxy in mollusk shells. In the case of C. concholepas, Mg cannot be used straightforwardly as a SST proxy.

  1. The embryonic life history of the tropical sea hare Stylocheilus striatus (Gastropoda: Opisthobranchia) under ambient and elevated ocean temperatures.

    Science.gov (United States)

    Horwitz, Rael; Jackson, Matthew D; Mills, Suzanne C

    2017-01-01

    Ocean warming represents a major threat to marine biota worldwide, and forecasting ecological ramifications is a high priority as atmospheric carbon dioxide (CO2) emissions continue to rise. Fitness of marine species relies critically on early developmental and reproductive stages, but their sensitivity to environmental stressors may be a bottleneck in future warming oceans. The present study focuses on the tropical sea hare, Stylocheilus striatus (Gastropoda: Opisthobranchia), a common species found throughout the Indo-West Pacific and Atlantic Oceans. Its ecological importance is well-established, particularly as a specialist grazer of the toxic cyanobacterium, Lyngbya majuscula. Although many aspects of its biology and ecology are well-known, description of its early developmental stages is lacking. First, a detailed account of this species' life history is described, including reproductive behavior, egg mass characteristics and embryonic development phases. Key developmental features are then compared between embryos developed in present-day (ambient) and predicted end-of-century elevated ocean temperatures (+3 °C). Results showed developmental stages of embryos reared at ambient temperature were typical of other opisthobranch species, with hatching of planktotrophic veligers occurring 4.5 days post-oviposition. However, development times significantly decreased under elevated temperature, with key embryonic features such as the velum, statocysts, operculum, eyespots and protoconch developing approximately 24 h earlier when compared to ambient temperature. Although veligers hatched one day earlier under elevated temperature, their shell size decreased by approximately 20%. Our findings highlight how an elevated thermal environment accelerates planktotrophic development of this important benthic invertebrate, possibly at the cost of reducing fitness and increasing mortality.

  2. The embryonic life history of the tropical sea hare Stylocheilus striatus (Gastropoda: Opisthobranchia) under ambient and elevated ocean temperatures

    Science.gov (United States)

    Jackson, Matthew D.; Mills, Suzanne C.

    2017-01-01

    Ocean warming represents a major threat to marine biota worldwide, and forecasting ecological ramifications is a high priority as atmospheric carbon dioxide (CO2) emissions continue to rise. Fitness of marine species relies critically on early developmental and reproductive stages, but their sensitivity to environmental stressors may be a bottleneck in future warming oceans. The present study focuses on the tropical sea hare, Stylocheilus striatus (Gastropoda: Opisthobranchia), a common species found throughout the Indo-West Pacific and Atlantic Oceans. Its ecological importance is well-established, particularly as a specialist grazer of the toxic cyanobacterium, Lyngbya majuscula. Although many aspects of its biology and ecology are well-known, description of its early developmental stages is lacking. First, a detailed account of this species’ life history is described, including reproductive behavior, egg mass characteristics and embryonic development phases. Key developmental features are then compared between embryos developed in present-day (ambient) and predicted end-of-century elevated ocean temperatures (+3 °C). Results showed developmental stages of embryos reared at ambient temperature were typical of other opisthobranch species, with hatching of planktotrophic veligers occurring 4.5 days post-oviposition. However, development times significantly decreased under elevated temperature, with key embryonic features such as the velum, statocysts, operculum, eyespots and protoconch developing approximately 24 h earlier when compared to ambient temperature. Although veligers hatched one day earlier under elevated temperature, their shell size decreased by approximately 20%. Our findings highlight how an elevated thermal environment accelerates planktotrophic development of this important benthic invertebrate, possibly at the cost of reducing fitness and increasing mortality. PMID:28168118

  3. The embryonic life history of the tropical sea hare Stylocheilus striatus (Gastropoda: Opisthobranchia under ambient and elevated ocean temperatures

    Directory of Open Access Journals (Sweden)

    Rael Horwitz

    2017-02-01

    Full Text Available Ocean warming represents a major threat to marine biota worldwide, and forecasting ecological ramifications is a high priority as atmospheric carbon dioxide (CO2 emissions continue to rise. Fitness of marine species relies critically on early developmental and reproductive stages, but their sensitivity to environmental stressors may be a bottleneck in future warming oceans. The present study focuses on the tropical sea hare, Stylocheilus striatus (Gastropoda: Opisthobranchia, a common species found throughout the Indo-West Pacific and Atlantic Oceans. Its ecological importance is well-established, particularly as a specialist grazer of the toxic cyanobacterium, Lyngbya majuscula. Although many aspects of its biology and ecology are well-known, description of its early developmental stages is lacking. First, a detailed account of this species’ life history is described, including reproductive behavior, egg mass characteristics and embryonic development phases. Key developmental features are then compared between embryos developed in present-day (ambient and predicted end-of-century elevated ocean temperatures (+3 °C. Results showed developmental stages of embryos reared at ambient temperature were typical of other opisthobranch species, with hatching of planktotrophic veligers occurring 4.5 days post-oviposition. However, development times significantly decreased under elevated temperature, with key embryonic features such as the velum, statocysts, operculum, eyespots and protoconch developing approximately 24 h earlier when compared to ambient temperature. Although veligers hatched one day earlier under elevated temperature, their shell size decreased by approximately 20%. Our findings highlight how an elevated thermal environment accelerates planktotrophic development of this important benthic invertebrate, possibly at the cost of reducing fitness and increasing mortality.

  4. Discussion on candidate species of gastropoda organisms in toxicity testing%腹足纲动物毒性测试候选物种的研究

    Institute of Scientific and Technical Information of China (English)

    郑师梅; 周启星; 熊红霞

    2011-01-01

    随着对内分泌干扰物在腹足纲动物中危害性的关注,软体动物污染生态问题逐渐受到重视.基于该研究方向现有进展,就几种典型腹足纲动物作为化学品测试受试生物的候选物种进行了论述,认为4种前鳃亚纲生物(新西兰泥蜗、鱼盘螺、福寿螺和铜锈环棱螺)和1种肺螺亚纲生物(静水椎实螺)具有生态意义,可以作为标准受试生物来发展.相对于其他国外学者提议的4种生物,我国学者提议的铜锈环棱螺具有本土意义,在化学品毒性测试过程中应该受到重视.在以上论述基础上,对腹足纲动物毒性测试今后研究的发展方向进行了展望.%With an attention to the hazard of endocrine disrupters on gastropoda organisms, the pollution-ecological problem of mollusks is being concerned gradually. Based on the current progress in the research area, several typical gastropoda organisms were discussed as the candidate species of testing organisms in the toxicity testing of chemicals. In view of their ecological significance, the four candidate prosobranchia species (Potamopyrgus antipodarum, Valvata piscinalis, Pomacea lineate and Bellamya aeruginosa) and one pulmonata organism (Lymnaea stagnalis) were suggested to develop as the standard testing organisms. Compared with the four other organisms proposed by foreign scholars, Bellamya aeruginosa proposed by Chinese scholars is of indigenous significance. Thus, attentions should be paid to the species in the toxicity testing of chemicals. On the basis of above discussions, the aspects of research on gastropoda organisms as candidate species in the toxicity testing in the future were prospected.

  5. 评侗族大歌音乐诗剧《行歌坐月》%Review of the Dong Chorus Musical Drama-Song and Moon

    Institute of Scientific and Technical Information of China (English)

    傅安辉; 吴媛姣; 吴文梅

    2015-01-01

    《行歌坐月》是首个登上国家大剧院的侗族题材剧目。侗族大歌音乐诗剧《行歌坐月》在京首演成功,再一次证明了民族传统文化艺术可以焕发艺术新生。侗戏文化唯有扬弃和吐故纳新,才具有鲜活的生命力和欣欣向荣的发展前景。侗族大歌音乐诗剧《行歌坐月》作为探索传统与现代创作联手的范式,无疑是保护民族传统文化的新途径,更是探索发展民族文化产业的开路先锋。%Song and Moon is the first Dong theme drama to reach the national theatre, In Beijing,the successful premiere of the Dong Chorus Musical Drama—Song and Moon proved again that the national traditional culture and arts can be full of art renaissance, As a traditional paradigm in conjunction with modern creation,the drama is undoubtedly the new approach to protecting the national traditional cul-ture and the pioneer as well in exploring the development of the ethnic culture industry as.

  6. First estimates of the probability of survival in a small-bodied, high-elevation frog (Boreal Chorus Frog, Pseudacris maculata), or how historical data can be useful

    Science.gov (United States)

    Muths, Erin L.; Scherer, R. D.; Amburgey, S. M.; Matthews, T.; Spencer, A. W.; Corn, P.S.

    2016-01-01

    In an era of shrinking budgets yet increasing demands for conservation, the value of existing (i.e., historical) data are elevated. Lengthy time series on common, or previously common, species are particularly valuable and may be available only through the use of historical information. We provide first estimates of the probability of survival and longevity (0.67–0.79 and 5–7 years, respectively) for a subalpine population of a small-bodied, ostensibly common amphibian, the Boreal Chorus Frog (Pseudacris maculata (Agassiz, 1850)), using historical data and contemporary, hypothesis-driven information–theoretic analyses. We also test a priori hypotheses about the effects of color morph (as suggested by early reports) and of drought (as suggested by recent climate predictions) on survival. Using robust mark–recapture models, we find some support for early hypotheses regarding the effect of color on survival, but we find no effect of drought. The congruence between early findings and our analyses highlights the usefulness of historical information in providing raw data for contemporary analyses and context for conservation and management decisions.

  7. Descripción de un nuevo limácido de Menorca (Islas Baleares: Gigantomilax (Vitrinoides benjaminus sp. n. (Gastropoda, Pulmonata

    Directory of Open Access Journals (Sweden)

    Borredà, V.

    2008-06-01

    Full Text Available Descripción de un nuevo limácido de Menorca (Islas Baleares: Gigantomilax (Vitrinoides benjaminus sp. n. (Gastropoda, Pulmonata We describe a new endemic limacid slug, Gigantomilax (Vitrinoides benjaminus n. sp. and we compare it with the nearest species, particularly with Gigantomilax (V. majoricensis, another Balearic endemism. Characteristic features of this new species include its small size, translucid and smooth body, and totally grey dorsum with no bands or spots. The reproductive system shows a well developed vas deferens surrounded by the distal part of prostatic gland, a thin penial retractor muscle, swollen prostate and small distal genitalia. The recent redescription of Limax majoricensis by Wiktor et al. (2007 is discussed and we consider that these authors refer to G. benjaminus n. sp., and so we dessign the neotype of Gigantomilax (V. majoricensis.

  8. New location for Bulinus truncatus (Audouin, 1827 (Gastropoda: Planorbidae intermediate host of Schistosoma haematobium and its distribution in the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Dana, Elías D.

    2015-12-01

    Full Text Available This paper reports a new population of Bulinus truncatus (Audouin, 1827 (Gastropoda, Planorbidae found in the province of Almería (Southeast Spain. B. truncatus is an intermediate host of Schistosoma haematobium, the trematode which causes urinary schistosomiasis in humans. Individuals were identified to species level by double-nested PCR, resulting in 100% homology. This population is located under the driest climate conditions of the Iberian Peninsula. Data on the distribution of this species in the Iberian Peninsula was gathered and is provided in this paper. Improved knowledge of the distribution of Bulinus truncatus is key to assess the risk of new outbreaks of schistosomiasis in the Iberian Peninsula.En este trabajo se reporta una nueva población de Bulinus truncatus (Audouin, 1827 (Gastropoda, Planorbidae en la provincia de Almería (Sureste de España. Se trata de una especie que presenta considerable interés tanto zoológico como epidemiológico por su papel como hospedador intermediario de Schistosoma haematobium, responsable de la esquistosomiasis urogenital humana. Los ejemplares fueron determinados a nivel específico mediante PCR doble anidada, con un 100% de homología. Se trata de la población localizada más al Sureste y en condiciones de mayor aridez en la península Ibérica. Se recopilaron los datos de presencia publicados para conocer su distribución en la península. El conocimiento de la distribución de Bulinus truncatus es una pieza clave para evaluar el riesgo de nuevos focos de esquistosomiasis en la península Ibérica.

  9. Divergencia intraespecífica y código de barras de ADN en Systrophia helicycloides (Gastropoda, Scolodontidae

    Directory of Open Access Journals (Sweden)

    Pedro Romero

    2011-08-01

    Full Text Available El DNA barcoding es un análisis que se basa en la comparación de distancias genéticas para identificar especies utilizando principalmente un segmento del gen Citocromo C Oxidasa I (COI. Los retos para la identificación surgen al estudiar grupos que presentan gran diversidad genética como los moluscos. Por ello, los objetivos de nuestra investigación fueron estimar la divergencia intraespecífica en el molusco terrestre amazónico Systrophia helicycloides (Gastropoda, Scolodontidae y evaluar la utilización de los códigos de barras de ADN en la identificación molecular de esta especie. Las secuencias de nucleótidos fueron comparadas con las bases de datos Genbank y BOLD (Barcode of Life Data Systems. Se realizó un análisis de distancia genética mediante Neighbour Joining. Systrophia helicycloides presentó dos grupos de haplotipos con distancias genéticas intraespecíficas mayores a 4%. También se observó una superposición entre las distancias intraespecíficas y las interespecíficas. La gran divergencia intraespecífica puede estar relacionada a la rápida variación del genoma mitocondrial, la distribución poblacional de los moluscos la cual permite el aislamiento y diferenciación genética, y la presencia de polimorfismos ancestrales. Los perfiles COI enviados a la base de datos BOLD son los primeros registros para esta especie y permitieron diferenciar a Systrophia helicycloides de otras especies. Estos perfiles corroboran la gran variación que ocurre en el genoma mitocondrial de moluscos terrestres por lo que la asignación de especies en este grupo precisa de la combinación entre los valores de divergencia genética, la evaluación de sitios informativos y los estudios de taxonomía convencional.

  10. Finding your mate at a cocktail party: frequency separation promotes auditory stream segregation of concurrent voices in multi-species frog choruses.

    Directory of Open Access Journals (Sweden)

    Vivek Nityananda

    Full Text Available Vocal communication in crowded social environments is a difficult problem for both humans and nonhuman animals. Yet many important social behaviors require listeners to detect, recognize, and discriminate among signals in a complex acoustic milieu comprising the overlapping signals of multiple individuals, often of multiple species. Humans exploit a relatively small number of acoustic cues to segregate overlapping voices (as well as other mixtures of concurrent sounds, like polyphonic music. By comparison, we know little about how nonhuman animals are adapted to solve similar communication problems. One important cue enabling source segregation in human speech communication is that of frequency separation between concurrent voices: differences in frequency promote perceptual segregation of overlapping voices into separate "auditory streams" that can be followed through time. In this study, we show that frequency separation (ΔF also enables frogs to segregate concurrent vocalizations, such as those routinely encountered in mixed-species breeding choruses. We presented female gray treefrogs (Hyla chrysoscelis with a pulsed target signal (simulating an attractive conspecific call in the presence of a continuous stream of distractor pulses (simulating an overlapping, unattractive heterospecific call. When the ΔF between target and distractor was small (e.g., ≤3 semitones, females exhibited low levels of responsiveness, indicating a failure to recognize the target as an attractive signal when the distractor had a similar frequency. Subjects became increasingly more responsive to the target, as indicated by shorter latencies for phonotaxis, as the ΔF between target and distractor increased (e.g., ΔF = 6-12 semitones. These results support the conclusion that gray treefrogs, like humans, can exploit frequency separation as a perceptual cue to segregate concurrent voices in noisy social environments. The ability of these frogs to segregate

  11. Use of clearance rate in Choromytilus chorus (Bivalvia: Mytilidae as a non-destructive biomarker of aquatic pollution El uso de la tasa de aclaramiento en Choromytilus chorus (Bivalvia: Mytilidae como biomarcador no destructivo de la polución acuática

    Directory of Open Access Journals (Sweden)

    BEATRIZ TORO

    2003-06-01

    Full Text Available Reduction in clearance rate was observed in the mussel Choromytilus chorus in relation to the degree of environmental pollution. Three sampling sites included the polluted San Vicente Bay, middling polluted Corral Bay, and weakly polluted Yaldad Bay in southern Chile. Pollution levels were estimated by quantitative analysis of polynuclear aromatic hydrocarbons (PAHs in mussel tissue from the three sites. Mussels from San Vicente showed lowest clearance rates and highest PAHs levels in both spring 1998 and summer 1999. Populations from Corral and Yaldad showed generally low levels of PAHs, so the mussels from Yaldad showed the highest rates of clearance in comparison to Corral and San Vicente populations. The significant negative relationship (P Se observó un deterioro de la tasa de aclaramiento en Choromytilus chorus de acuerdo al grado de polución ambiental. Se incluyeron tres sitios de muestreos, la bahía de San Vicente muy contaminada, la bahía de Corral con una polución intermedia y la bahía de Yaldad, al sur de Chile, con una baja contaminación. Los niveles de polución fueron estimados por análisis cuantitativos de hidrocarburos aromáticos polinucleares (HAPs en el tejido de los choros zapatos de los tres sitios de muestreo. Los choros zapatos de San Vicente mostraron la menor tasa de aclaramiento y altos niveles de HAPs, tanto en la primavera de 1998 como en el verano de 1999. Las poblaciones de Corral y Yaldad mostraron en general bajos niveles de HAPs, en tanto que los ejemplares de Yaldad presentaron altas tasas de aclaramiento en comparación con las poblaciones de Corral y San Vicente. La relación negativa significativa (P < 0,001 entre la polución en el tejido de los choros zapatos y sus tasas de aclaramiento, argumenta la utilidad del método como un biomarcador no destructivo para evaluar el impacto ambiental de la polución en las especies marinas

  12. 产抗真菌蛋白(AFP)巨大曲霉的分离鉴定及AFP的提纯%The Screening of a Antifungal Protein(AFP)-Producing Aspergillus giganteus and Purification of AFP

    Institute of Scientific and Technical Information of China (English)

    元月; 王德良; 郭立芸; 林智平; 江伟

    2012-01-01

    从土壤中分离出1株可产抗真菌蛋白的菌株,通过形态观察和分子生物学实验等方法鉴定其为巨大曲霉,编号AF-11。研究证明,利用纤维素阳离子交换柱层析法和凝胶柱层析法可从该菌的发酵上清液中分离纯化出高活性的抗真菌蛋白(AFP),该蛋白对青霉属、曲霉属和镰刀霉属等产毒丝状真菌的生长具有明显的抑制作用。%A strain which can produce antifungal protein was isolated from soil and was identified as Aspergillus giganteus,numbered AF-11,through morphologic observation and molecular biology experiments.It has been proven that the high activity and purity antifungal protein(AFP) which can obviously inhibit the growth of filamentous fungi such as Penicillium,Aspergillus and Fusarium,can be separated from the fermentation supernatant by using cellulose cation exchange column chromatography and gelatin column chromatography.

  13. The influence of light quality on C4 photosynthesis under steady-state conditions in Zea mays and Miscanthus×giganteus: changes in rates of photosynthesis but not the efficiency of the CO2 concentrating mechanism.

    Science.gov (United States)

    Sun, Wei; Ubierna, Nerea; Ma, Jian-Ying; Cousins, Asaph B

    2012-05-01

    Differences in light quality penetration within a leaf and absorption by the photosystems alter rates of CO(2) assimilation in C(3) plants. It is also expected that light quality will have a profound impact on C(4) photosynthesis due to disrupted coordination of the C(4) and C(3) cycles. To test this hypothesis, we measured leaf gas exchange, (13) CO(2) discrimination (Δ(13) C), photosynthetic metabolite pools and Rubisco activation state in Zea mays and Miscanthus × giganteus under steady-state red, green, blue and white light. Photosynthetic rates, quantum yield of CO(2) assimilation, and maximum phosphoenolpyruvate carboxylase activity were significantly lower under blue light than white, red and green light in both species. However, similar leakiness under all light treatments suggests the C(4) and C(3) cycles were coordinated to maintain the photosynthetic efficiency. Measurements of photosynthetic metabolite pools also suggest coordination of C(4) and C(3) cycles across light treatments. The energy limitation under blue light affected both C(4) and C(3) cycles, as we observed a reduction in C(4) pumping of CO(2) into bundle-sheath cells and a limitation in the conversion of C(3) metabolite phosphoglycerate to triose phosphate. Overall, light quality affects rates of CO(2) assimilation, but not the efficiency of CO(2) concentrating mechanism.

  14. A Study of Present Situation and Countermeasures of Primary School Chorus Education in the Undeveloped Areas——A Case Study of the Northern Mountainous Guangdong%经济欠发达地区小学合唱教育现状与对策研究——基于广东省粤北山区的实证研究

    Institute of Scientific and Technical Information of China (English)

    张鸿舜

    2011-01-01

    随着素质教育、创新教育、新课改的不断深入,合唱教育在小学音乐教育中日益得到更多的重视.近年来,珠江三角洲成为了中国合唱艺术最活跃的地区之一,作为其重要组成部分的小学合唱教育也得到了蓬勃的发展,但同属广东省的韶关地区小学合唱教育的情况就不容乐观.文章通过对小学教师与学生的问卷调查、个别访谈、文献分析等形式的调查研究,对韶关地区小学合唱教育的现状进行深入的调查分析,并寻找影响合唱教育水平的重要因素,寻求改善本地区小学合唱教育状况的对策.%Following the deep development of quality education,enterprising education and reforms of new courses,chorus education is gradually attached great importance in the musical education of primary schools.In recent years,the Pearl River Delta has become one of the most active areas for China's chorus arts,Primary school chorus education,as an important part of chorus arts,also develops prosperously.But its current situation in Shaoguan area is not so optimistic.This essay,which makes a deep survey and analysis on the current state of primary school chorus education in Shaoguan area,is trying to search for important factors influencing chorus education quality and to find solution contributing to the improvement of local chorus educating situation through forms of questionnaire,individual interviews and documentary analysis.

  15. 不同供锗水平对巨大革耳子实体可溶性蛋白和细胞保护酶活性的影响%Soluble Protein,Superoxide Dismutase, Peroxidase,Polyphenol Oxidase and Catalase Levels in Panus giganteus Fruit Bodies Grown on Substrates Supplemented with Different Concentrations of Germanium

    Institute of Scientific and Technical Information of China (English)

    颜振兰

    2014-01-01

    研究培养料中锗(Ge)不同添加水平对巨大革耳(Panus giganteus)子实体内可溶性蛋白含量和超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)等细胞保护酶活性的影响。结果表明,Ge 添加浓度为18 mg/kg时,巨大革耳子实体内可溶性蛋白含量、SOD和 POD活性平均分别比对照提高8.80%、193.9%和43.3%,与对照间差异极显著(P<0.01);CAT活性也平均比对照提高8.9%,与对照差异显著(P<0.05)。%Superoxide dismutase (SOD),peroxidase (POD),polyphenol oxidase (PPO),catalase (CAT)and soluble protein levels were determined in Panus giganteus fruit bodies grown on substrates supplemented with different GeO2 concentrations.Soluble protein,SOD,POD and CAT levels in P.giganteus fruit bodies cultivated on a substrate supplemented with 18 mg/kg GeO2 were 8.8% (P<0.01),193.9% (P<0.01), 43.3% (P<0.01)and 8.9% (P<0.05)higher,respectively compared to controls grown without added germanium.

  16. Review of palaeozygopleurid gastropods (Palaeozygopleuridae, Gastropoda) from Devonian strata of the Perunica microplate (Bohemia), with a re-evaluation of their stratigraphic distribution, notes on their ontogeny, and descriptions of new taxa.

    Science.gov (United States)

    Frýda, Jiři; Ferrová, Lenka; Frýdová, Barbora

    2013-01-01

    Review of all species of the family Palaeozygopleuridae Horný, 1955 (Gastropoda) known from the Perunica microplate (Bohemia) is presented with a description of three new species, Palaeozygopleura lukesi sp. nov., Cimrmaniela sveraki gen. et sp. nov. and Cimrmaniela smoljaki gen. et sp. nov. The stratigraphic distributions of the most of Bohemian palaeozygopleurid species are either corrected or refined, based on new records or modern stratigraphic studies. A complete list of the geographic occurrences of all known palaeozygopleurid gastropods from the Perunica microplate is also given together with notes on their ontogeny.

  17. Intervention of Multi-part Chorus on Mental Health Status of Adult Prisoners%多声部合唱对罪犯心理健康状况的干预研究

    Institute of Scientific and Technical Information of China (English)

    王莉; 练恒胜; 刘小超; 高歌

    2014-01-01

    Objectives To explore the effect of multi-part chorus on mental health in adult prisoners and to give refer-ence for psychological treatment in criminal theory of reforming practice.Methods Sixty prisoners were randomly chosen as research objects and divided into control and intervention group.The intervention group practiced multi-part chorus and were followed up for 3 months.The effect of intervention was evaluated with Self-Rating Anxiety Scale (SAS),Trust Scale,Social Avoidance and Distress Scale (SAD),shyness scale,UCLA loneliness Scale (UCLA),and Chinese Offender Psychological Assessment-Personality Inventory (COPA-PI).Results Compared with the control group,the differ-ences in anxiety,trust-d,loneliness,social avoidance and distress,extraversion and impulse showed significant change in the intervention group before and after intervention.Conclusions Multi-part chorus is an effective way to improve mental healthiness and promote psychological health level of prisoners.%目的:探讨多声部合唱干预对罪犯心理健康状况的影响,为监狱心理矫治工作提供参考。方法选取狱中60名罪犯作为受试对象,随机分为试验组与对照组。采用多声部合唱方法对试验组罪犯的心理健康状况进行干预试验,观察3个月。于干预前后采用焦虑自评量表、信任量表、社交回避及苦恼量表、羞怯量表、UCLA 孤独量表、中国罪犯心理测试个性分测验(COPA-PI)对其进行心理测试和评估。结果试验组罪犯群体经过多声部合唱干预前后与对照组罪犯群体对比,在焦虑、信任-D、孤独、社交回避与苦恼、COPA-PI(外倾、冲动)等因子差异具有统计学意义。结论多声部合唱能有效改善罪犯群体的心理健康状况,提高罪犯的心理健康水平。

  18. A new approach to an old conundrum--DNA barcoding sheds new light on phenotypic plasticity and morphological stasis in microsnails (Gastropoda, Pulmonata, Carychiidae).

    Science.gov (United States)

    Weigand, Alexander M; Jochum, Adrienne; Pfenninger, Markus; Steinke, Dirk; Klussmann-Kolb, Annette

    2011-03-01

    The identification of microsnail taxa based on morphological characters is often a time-consuming and inconclusive process. Aspects such as morphological stasis and phenotypic plasticity further complicate their taxonomic designation. In this study, we demonstrate that the application of DNA barcoding can alleviate these problems within the Carychiidae (Gastropoda, Pulmonata). These microsnails are a taxon of the pulmonate lineage and most likely migrated onto land independently of the Stylommatophora clade. Their taxonomical classification is currently based on conchological and anatomical characters only. Despite much confusion about historic species assignments, the Carychiidae can be unambiguously subdivided into two taxa: (i) Zospeum species, which are restricted to karst caves, and (ii) Carychium species, which occur in a broad range of environmental conditions. The implementation of discrete molecular data (COI marker) enabled us to correctly designate 90% of the carychiid microsnails. The remaining cases were probably cryptic Zospeum and Carychium taxa and incipient species, which require further investigation into their species status. Because conventional reliance upon mostly continuous (i.e. nondiscrete) conchological characters is subject to fallibility for many gastropod species assignments, we highly recommend the use of DNA barcoding as a taxonomic, cutting-edge method for delimiting microsnail taxa.

  19. Patterns of larval distribution and settlement of Concholepas concholepas (Bruguiere, 1789 (Gastropoda, Muricidae in fjords and channels of southern Chile Patrones de distribución de larvas y asentamiento de Concholepas concholepas (Bruguiere, 1789 (Gastropoda, Muricidae en fiordos y canales del sur de Chile

    Directory of Open Access Journals (Sweden)

    CARLOS MOLINET

    2005-09-01

    Full Text Available The distribution of Concholepas concholepas (Mollusca, Gastropoda, Muricidae is limited to the coasts of Chile and southern Peru. Almost all studies of this gastropod have been carried out in open coastal systems, rather than the fjords and channels of southern Chile, despite the fact that this area represents ca. 95 % of the total coastline in this country. Although there is a large volume of background literature on C. concholepas, almost nothing is published about early larval development under natural conditions, mostly because early veligers have rarely been found in nature. This study is the first attempt to determine the spatial and temporal abundance and size patterns of C. concholepas larvae in their natural environment throughout all of their developmental stages until they settle. Weekly plankton samples were obtained at the surface and at 8 m depth in four locations in southern Chile in combination with temperature and salinity records in each location. Settlement was quantified using artificial substrates in all locations. We have observed that C. concholepas larval development occurs throughout the entire year in Chilean inland seas, with early veliger larvae being released mostly from August to March, reaching the competent stage around June to August, and settling between July and August. Thus, larvae appear to have a long planktonic development that can last between 6 and 12 months. Differences in local hydrology could affect larval development of C. concholepas in this region. Further oceanographic and ecological investigation is necessary in order to answer the questions and hypotheses originated from this studyConcholepas concholepas (Mollusca, Gastropoda, Muricidae se distribuye entre las costas del sur de Perú y extremo sur de Chile. Prácticamente todos los estudios sobre este gastrópodo han sido realizados en costas expuestas, sin considerar los fiordos y canales del sur de Chile, a pesar de que estos representan

  20. Mastering the art implied meaning and feeling the beauty of the music——discussion on use of synaesthesia experience in college students' chorus training%通艺术深意感音乐之美——浅议通感体验在大学生合唱训练中的运用

    Institute of Scientific and Technical Information of China (English)

    邓婷婷

    2012-01-01

      音乐不仅是听觉的艺术,还是“多觉”最终归于“心觉”的艺术。艺术通感研究是人类审美和艺术活动研究的重要组成部分,也是当前艺术教育深化改革的迫切需求。文章立足于大学生合唱教育的视阈,针对当今大学生合唱艺术感染力不强的特点,对通感及相关的教育启示进行了研究,在认识通感体验的基础上,提出了通感体验运用到合唱训练的方法。%  Music is not only the art of hearing but also art of " more sense" ultimately attributed to "heart sense " . Artistic synaesthesia research are important components of human aesthetic and artistic activity, is also the current urgent needs of deepening the reform of art education. Based on the college students' chorus perspective education, According to features that choral artistic appeal of today college students are not strong, synesthesia and related to education were studied, On the basis of understanding the experience of synesthesia, methods of Synaesthetic experience applied in chorus training were proposed.

  1. Mollusks (Gastropoda and Bivalvia) of the Multiple-Use Reserve Martín García Island, Río de la Plata River: biodiversity and ecology.

    Science.gov (United States)

    César, I I; Martín, S M; Rumi, A; Tassara, M

    2012-02-01

    The Island of Martin Garcia is located in the Upper Río de la Plata, to the south of mouth the Uruguay River. The aim of the present study was to analyse the biodiversity of the island freshwater mollusks and their relationships to environmental variables. Twelve sampling sites were selected, five were along the littoral section of the island and seven were Inland ponds. Seven major environmental variables were measured: water and air temperature, percentage of oxygen saturation, dissolved oxygen, electrical conductivity, total dissolved solids and pH. Twenty-seven mollusk species were found, Antillorbis nordestensis, Biomphalaria tenagophila tenagophila , B. t. guaibensis, B. straminea, B. peregrina, Drepanotrema kermatoides, D. cimex, D. depressissimum, Chilina fluminea, C. rushii, C. megastoma, Uncancylus concentricus, Hebetancylus moricandi, Stenophysa marmorata, Heleobia piscium, H. parchappii, Potamolithus agapetus, P. buschii, P. lapidum, Pomacea canaliculata, P. megastoma, Asolene platae, Corbicula fluminea, Eupera platensis, Pisidium sterkianum, P. taraguyense and Limnoperna fortunei. UPGMA clustering of species based on their occurrence in different ecological conditions revealed two main species groups. The Canonical Correspondence Analysis suggests that the species distribution is related to the physico-chemical condition of water. Axis two of the ordination diagram displayed the approximately 95.6% of the correlation between species and environmental variables. Dissolved oxygen, conductivity, water temperature and pH showed the highest fluctuations during the sampling period. The species richness (S) showed relationships mainly with water temperature and conductivity. The biodiversity of the gastropods and bivalves from Martín García Island amounts to up to 26 species. Among the Gastropoda, the Planorbidae family made the most sizeable contribution. The Lithogliphidae P. agapetus (26.28%) and P. buschii (9.50%) showed the highest relative

  2. 广东作曲家流行音乐交响化创作的实践——以21首用流行歌曲改编的交响合唱为例%The Practice of Guangdong Composers' Symphonic Creation on Popular Music: with 21 symphony chorus recomposed from popular songs for example

    Institute of Scientific and Technical Information of China (English)

    何平; 潘谊

    2012-01-01

    It has apparently been a powerful brushstroke in the history of Guangdong popular music that popular music has been performed in the form of a symphony chorus. "Tao Sheng Yi Jiusymphony chorus concert for the 30th anniversary of Guangdong popular music" is of great historical significance. The holding of this concert has proved that popular music and classical music (symphonic music or serious music) have no insurmountable gap in terms of the content and the form ; and that the development of popular music has its own tradition, but the diversi- fied forms of expression will provide wider development space for popular music. The recomposed work of these 21 popular songs performed in the concert with the form of Symphony Chorus is based on two principles: be faithful to the original basic style; and to innovate on the basis of origin. This has actually set the high creation principle for people doing the work. The 21 pieces of adaptation eventually created three types of works. Meanwhile, Guangdong Composers" choreographing practice on popular music makes it possible for people to have an opportunity to reflect on the artistic value of popular music.%将流行音乐作品以交响合唱的形式重新进行演绎,显然在广东流行音乐发展史上具有浓烈的一笔。“涛声依旧——广东流行音乐30周年交响合唱音乐会”,就是这样具有历史意义的一笔。音乐会的举办,给人们提出了两点参考:流行音乐与古典音乐(或交响音乐、严肃音乐)在内容和形式上并没有什么不可逾越的鸿沟;流行音乐的发展固然有自己的传统,但多元化的表现形式,将为流行音乐提供更为广阔的发展空间。音乐会上演出的21首交响合唱形式的流行歌曲,其改编工作,基于两点原则:忠实于原创的基本品格;在忠于原创的基础上进行创新。这实际上为改编者提出了较高的创作原则。21首作品的改编最终形

  3. Atmospheric physics: Chorus keeps the diffuse aurora humming

    Science.gov (United States)

    Newell, Patrick T.

    2010-10-01

    The origin of the diffuse aurora, whose beauty and intensity pale beside those of the famous aurora borealis, has remained controversial. A convincing explanation for this auroral display is now at hand. See Letter p.943

  4. Excitation of Whistler-Mode (Chorus) Emissions during Terrestrial Substorms

    Institute of Scientific and Technical Information of China (English)

    XIAO Fu-Liang; ZHAO Hua; HE Hui-Yong

    2005-01-01

    @@ The enhanced growth rate of whistler mode waves has been evaluated during an injection event associated with an isolated terrestrial substorm that occurred at 23:00 UT, on January 21, 1991. The electron phase space density observed by an LEPA instrument on the board of the CRRES spacecraft is modelled by using a bi-loss-cone distribution function (composed of a high anisotropic component and a quasi-isotropic component). During the injection event, the path integrated gain may increase by a factor of 5 over a frequency range near a few tenths of the electron gyrofrequency, which is consistent with the enhancement observed in the CRRES plasma wave experiment (PWE) emissions. Scattering of electrons by the enhanced whistler mode waves causes the pitch angle distribution of resonant electrons to a quasi isotropic (flat-top) distribution during the terrestrial substorm injection event.

  5. Focal Chorus 826W特别版音箱

    Institute of Scientific and Technical Information of China (English)

    赵聪; 庄宏道(摄影)

    2012-01-01

    要说法国Focal音箱的代表作,无疑是新乌托邦系列。新乌托邦系列中的型号,无论是旗舰的Grande Utopia EM,还是稍小一号的Stella Utopia EM,都是同价位音箱中的佼佼者,

  6. Focal Chorus806V书架扬声器

    Institute of Scientific and Technical Information of China (English)

    阿闰

    2007-01-01

    法国扬声器生产商Focal最为人所称道的就是他的旗舰级Utopia系列,由上一代的Utopia到新世代的UtopiaBe,都是非常靓声而且表现全面。我作为上一代MezzoUtopia的长期用家,可以肯定的说,用了它,你根本没有办法在同等价位找到任何对手。Focal虽然精于制作真正Hi—End级别的扬声器,幸好她并没有忘记普罗大众发烧友,除了推出Utopia以下一级的中档Electra系列,还有入门级的Chorus系列,让知悭识俭的发烧朋友能够付出适合自己的价值,享受Focal富有活力的声音。

  7. Callus induction and plant regeneration from different explant types of Miscanthus x ogiformis Honda 'Giganteus'

    DEFF Research Database (Denmark)

    Holme, Inger Bæksted; Petersen, Karen Koefoed

    1996-01-01

    . The explants were cultured on urashige and Skoog medium supplemented with 4.5, 13.6, 22.6 or 31.7 μM 2,4-dichlorophenoxyacetic acid. Three types of callus were formed but only one was embryogenic and regenerated plants. Callus induction and formation of embryogenic callus depended on the type and developmental...

  8. Kinetics of levulinic acid and furfural production from Miscanthus × giganteus.

    Science.gov (United States)

    Dussan, K; Girisuta, B; Haverty, D; Leahy, J J; Hayes, M H B

    2013-12-01

    This study investigated the kinetics of acid hydrolysis of the cellulose and hemicellulose in Miscanthus to produce levulinic acid and furfural under mild temperature and high acid concentration. Experiments were carried out in an 8L-batch reactor with 9%-wt. biomass loading, acid concentrations between 0.10 and 0.53 M H2SO4, and at temperatures between 150 and 200°C. The concentrations of xylose, glucose, furfural, 5-hydroxymethylfurfural and levulinic acid were used in two mechanistic kinetic models for the prediction of the performance of ideal continuous reactors for the optimisation of levulinic acid and the concurrent production of furfural. A two-stage arrangement was found to maximise furfural in the first reactor (PFR - 185°C, 0.5M H2SO4, 27.3%-mol). A second stage leads to levulinic acid yields between 58% and 72%-mol at temperatures between 160 and 200°C.

  9. A Reproductive Management Program for an Urban Population of Eastern Grey Kangaroos (Macropus giganteus

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    Andrew Tribe

    2014-09-01

    Full Text Available Traditionally, culling has been the expedient, most common, and in many cases, the only tool used to control free-ranging kangaroo populations. We applied a reproductive control program to a population of eastern grey kangaroos confined to a golf course in South East Queensland. The program aimed to reduce fecundity sufficiently for the population to decrease over time so that overgrazing of the fairways and the frequency of human–animal conflict situations were minimised. In 2003, 92% of the female kangaroos above 5 kg bodyweight were implanted with the GnRH agonist deslorelin after darting with a dissociative anaesthetic. In 2007, 86% of the females above 5 kg were implanted with deslorelin and also 87% of the males above 5 kg were sterilised by either orchidectomy or vasectomy. In 2005, 2008 and 2009, the population was censused to assess the effect of each treatment. The 2003 deslorelin program resulted in effective zero population growth for approximately 2.5 years. The combined deslorelin–surgery program in 2007 reduced the birth rate from 0.3 to 0.06%/year for 16 months, resulting in a 27% population reduction by November 2009. The results were consistent with implants conferring contraception to 100% of implanted females for at least 12 months. The iatrogenic mortality rates for each program were 10.5% and 4.9%, respectively, with 50% of all mortalities due to darting-related injuries, exertional myopathy/hyperthermia or recovery misadventure. The short term sexual and agonistic behaviour of the males was assessed for the 2007 program: no significant changes were seen in adult males given the vasectomy procedure, while sexual behaviours’ were decreased in adult males given the orchidectomy procedure. It is concluded that female reproduction was effectively controlled by implantation with deslorrelin and male reproductive behaviour was reduced by orchidectomy, which together achieved population control.

  10. Imposex in endemic volutid from Northeast Brazil (Mollusca: Gastropoda

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    Ítalo Braga de Castro

    2008-10-01

    Full Text Available Imposex is characterized by the development of masculine sexual organs in neogastropod females. Almost 120 mollusk species are known to present imposex when exposed to organic tin compounds as tributyltin (TBT and triphenyltin (TPT. These compounds are used as biocide agents in antifouling paints to prevent the incrustations on boats. Five gastropod species are known to present imposex in Brazil: Stramonita haemastoma, Stramonita rustica, Leucozonia nassa, Cymathium parthenopeum and Olivancillaria vesica. This paper reports the first record of imposex observed in the endemic gastropod Voluta ebraea from Pacheco Beach, Northeast Brazil. Animals presenting imposex had regular female reproductive organs (capsule gland, oviduct and sperm-ingesting gland and an abnormal penis. As imposex occurs in mollusks exposed to organotin compounds typically found at harbors, marinas, shipyards and areas with high shipping activities, probably contamination of Pacheco Beach is a consequence of a shipyard activity located in the nearest areas.O imposex caracteriza-se pelo surgimento de estruturas sexuais masculinas, em fêmeas de gastrópodes. Cerca de 120 espécies de moluscos que exibem o fenômeno quando expostas a contaminação por compostos orgânicos de estanho tais como o Tributilestanho (TBT e o Trifenilestanho (TPT. Esses compostos são utilizados, sobretudo em embarcações, no intuito de evitar a bioincrustração que danifica as embarcações e eleva os custos das viagens marítimas. No Brasil se conhecem 5 espécies de moluscos gastrópodes que manifestam imposex, são elas: Stramonita haemastoma, Stramonita rustica, Leucozonia nassa, Cymathium parthenopeum e Olivancillaria vesica. No Nordeste, monitoramentos da contaminação por organoestânicos foram realizados utilizando o imposex em gastrópodes como biomarcador. O presente estudo tem por objetivo notificar a primeira ocorrência de imposex na espécie endêmica do Nordeste brasileiro, Voluta ebraea. De um total de 11 animais observados, duas fêmeas apresentaram imposex, provenientes da Praia do Pacheco no litoral do Ceará. Observou-se nesses indivíduos a presença de glândula de cápsulas, ovidutos e receptáculo seminal concomitantemente ao pênis o que caracteriza o imposex. Como o imposex só se manifesta em moluscos expostos a compostos organoestânicos tipicamente encontrados em portos, marinas, estaleiros e locais com grande fluxo de embarcações atribui-se a origem dessa contaminação provavelmente a um estaleiro localizado nas proximidades da área de coleta.

  11. Phylogenetic analysis of Biomphalaria tenagophila (Orbigny, 1835 (Mollusca: Gastropoda

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    Liana K Jannotti-Passos

    2010-07-01

    Full Text Available Mitochondrial DNA of Biomphalaria tenagophila, a mollusc intermediate host of Schistosoma mansoni in Brazil, was sequenced and characterised. The genome size found for B. tenagophila was 13,722 bp and contained 13 messenger RNAs, 22 transfer RNAs (tRNA and two ribosomal RNAs (rRNA. In addition to sequencing, the mitochondrial DNA (mtDNA genome organization of B. tenagophila was analysed based on its content and localization of both coding and non-coding regions, regions of gene overlap and tRNA nucleotide sequences. Sequences of protein, rRNA 12S and rRNA 16S nucleotides as well as gene organization were compared between B. tenagophila and Biomphalaria glabrata, as the latter is the most important S. mansoni intermediate host in Brazil. Differences between such species were observed regarding rRNA composition. The complete sequence of the B. tenagophila mitochondrial genome was deposited in GenBank (accession EF433576. Furthermore, phylogenetic relationships were estimated among 28 mollusc species, which had their complete mitochondrial genome deposited in GenBank, using the neighbour-joining method, maximum parsimony and maximum likelihood bootstrap. B. tenagophila was positioned at a branch close to B. glabrata and Pulmonata molluscs, collectively comprising a paraphyletic group, contrary to Opistobranchia, which was positioned at a single branch and constituted a monophyletic group.

  12. Transferência do gênero monotípico Parodizia Medina de Bithyniidae (Gastropoda, Prosobranchia para Pyramidellidae (Gastropoda, Heterobranchia Transference of the monotypic genus Parodizia Medina from Bithyniidae Gray (Gastropoda, Prosobranchia to Pyramidellidae Gray (Gastropoda, Heterobranchia

    Directory of Open Access Journals (Sweden)

    Maria Cristina Pons da Silva

    2004-06-01

    Full Text Available Propõe-se a transferência do gênero monitípico Parodizia Medina, 1959 de Bithyniidae (Prosobranchia para Pyramidellidae (Heterobranchia. A proposta está baseada em dados morfológicos de espécimens de P. uruguayensis Medina, 1959 procedentes da bacia do rio Tramandaí, Rio Grande do Sul, Brasil.The transference of the monotypic genus Parodizia Medina, 1959 from Bithyniidae (Prosobranchia to Pyramidellidae (Heterobranchia is proposed. The proposal is based on some morphological data of P. uruguayensis Medina, 1959 from Tramandaí river basin, Rio Grande do Sul, Brazil.

  13. Miscellaneous notes on Southern African Gastropoda Euthyneura (Mollusca)

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1967-01-01

    SUMMARY The following new distribution records of southern African terrestrial molluscs seem to be of particular interest: Pupilla fontana (Krss.), Rachis jejuna (M. & P.), Guppya rumrutiensis (Prest.), Xerocerastus burchelli (Gray) (all four new for Rhodesia), Euonyma damarica Jaeck. (new for Cape

  14. Untersuchungen zum Harnsäuremetabolismus von Littorina littorea (Gastropoda)

    Science.gov (United States)

    Heil, K. P.; Eichelberg, D.

    1983-12-01

    Periwinkles, as typical inhabitants of sea-shores, are subjected to extreme changes of environmental conditions, which affect their excretion. In Littorina littorea uric acid, urea and ammonium were detected particularly in the kidney, but the only metabolite excreted was ammonium. Only the concentration of uric acid was dependent on the availability of water; decreasing periods of submersion during low tide and raised salinities caused a higher concentration of uric acid, while increasing periods of submersion and lowered salinities effected the opposite. Transfer of periwinkles within their intertidal habitat and laboratory experiments to test the effect of salinity showed that the concentration of uric acid in the kidney is adaptable. The dependence of uric acid concentration in the kidney on environmental conditions and the ammoniotelic excretion of L. littorea are discussed with regard to its particular living conditions. It is suggested that uric acid serves as nitrogen depot and has a particular function in osmoregulation.

  15. Two new species of Enidae (Mollusca: Gastropoda: Pupillacea) from Turkey

    NARCIS (Netherlands)

    Gittenberger, E.

    1986-01-01

    Two new species of Enidae, viz. Zebrina (Ramusculus) mienisi spec. nov. and Turanena tuccari spec. nov., are described from the Turkish provinces of Erzurum and Antalya, respectively. The former species is unknown anatomically and, therefore, its (sub)generic assignment is uncertain. The latter new

  16. New data on southern African Achatinidae (Mollusca, Gastropoda Pulmonata)

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1972-01-01

    Increasing knowledge of the genital anatomy of the species of the African land snail family Achatinidae has greatly improved our understanding of the delimitation of the species and the intricate interrelationships of the various taxa (Mead, 1950). The genitalia of many achatinids are still unknown

  17. Silurian Gastropoda from the Alexander terrane, southeast Alaska

    Science.gov (United States)

    Rohr, D.M.; Blodgett, R.B.

    2008-01-01

    Gastropods are described from Ludlow-age strata of the Heceta Limestone on Prince of Wales Island, southeast Alaska. They are part of a diverse megabenthic fauna of the Alexander terrane, an accreted terrane of Siberian or Uralian affinities. Heceta Limestone gastropods with Uralian affinities include Kirkospira glacialis, which closely resembles "Pleurotomaria" lindstromi Oehlert of Chernyshev, 1893, Retispira cf. R. volgulica (Chernyshev, 1893), and Medfracaulus turriformis (Chernyshev, 1893). Medfracaulus and similar morphotypes such as Coelocaulus karlae are unknown from rocks that are unquestionably part of the North American continent (Laurentia) during Late Silurian time. Beraunia is previously known only from the Silurian of Bohemia. Pachystrophia has previously been reported only from western North American terranes (Eastern Klamath, York, and Farewell terranes) and Europe. Bathmopterus Kirk, 1928, is resurrected and is only known from the Silurian of southeast Alaska. Newly described taxa include Hecetastoma gehrelsi n. gen. and n. sp. and Baichtalia tongassensis n. gen. and n. sp. ??2008 The Geological Society of America.

  18. Host specificity and phylogenetic relationships among Atlantic Ovulidae (Mollusca: Gastropoda)

    NARCIS (Netherlands)

    Reijnen, B.T.; Hoeksema, B.W.; Gittenberger, E.

    2010-01-01

    Ovulid gastropods and their octocoral hosts were collected along the leeward coast of Curaçao, Netherlands Antilles. New molecular data of Caribbean and a single Atlantic species were combined with comparable data of Indo-Pacific Ovulidae and a single East-Pacific species from GenBank. Based on two

  19. Host specificity and phylogenetic relationships among Atlantic Ovulidae (Mollusca: Gastropoda)

    OpenAIRE

    2010-01-01

    Ovulid gastropods and their octocoral hosts were collected along the leeward coast of Curaçao, Netherlands Antilles. New molecular data of Caribbean and a single Atlantic species were combined with comparable data of Indo-Pacific Ovulidae and a single East-Pacific species from GenBank. Based on two DNA markers, viz. CO-I and 16S, the phylogenetic relationships among all ovulid species of which these data are available are reconstructed. The provisional results suggest a dichotomy between the ...

  20. Evidence for the validity of Protatlanta sculpta (Gastropoda: Pterotracheoidea)

    NARCIS (Netherlands)

    Wall-Palmer, D.; Burridge, A.K.; Peijnenburg, K.C.T.A.; Janssen, A.; Goetze, E.; Kirby, R.; Hart, M.B.; Smart, C.W.

    2016-01-01

    The genus Protatlanta is thought to be monotypic and is part of the Atlantidae, a family of shelled heteropods. These microscopic planktonic gastropods are poorly known, although research on their ecology is now increasing in response to concerns about the effects of ocean acidification on calcareou

  1. Molecular phylogeny and evolution of the cone snails (Gastropoda, Conoidea).

    Science.gov (United States)

    Puillandre, N; Bouchet, P; Duda, T F; Kauferstein, S; Kohn, A J; Olivera, B M; Watkins, M; Meyer, C

    2014-09-01

    We present a large-scale molecular phylogeny that includes 320 of the 761 recognized valid species of the cone snails (Conus), one of the most diverse groups of marine molluscs, based on three mitochondrial genes (COI, 16S rDNA and 12S rDNA). This is the first phylogeny of the taxon to employ concatenated sequences of several genes, and it includes more than twice as many species as the last published molecular phylogeny of the entire group nearly a decade ago. Most of the numerous molecular phylogenies published during the last 15years are limited to rather small fractions of its species diversity. Bayesian and maximum likelihood analyses are mostly congruent and confirm the presence of three previously reported highly divergent lineages among cone snails, and one identified here using molecular data. About 85% of the species cluster in the single Large Major Clade; the others are divided between the Small Major Clade (∼12%), the Conus californicus lineage (one species), and a newly defined clade (∼3%). We also define several subclades within the Large and Small major clades, but most of their relationships remain poorly supported. To illustrate the usefulness of molecular phylogenies in addressing specific evolutionary questions, we analyse the evolution of the diet, the biogeography and the toxins of cone snails. All cone snails whose feeding biology is known inject venom into large prey animals and swallow them whole. Predation on polychaete worms is inferred as the ancestral state, and diet shifts to molluscs and fishes occurred rarely. The ancestor of cone snails probably originated from the Indo-Pacific; rather few colonisations of other biogeographic provinces have probably occurred. A new classification of the Conidae, based on the molecular phylogeny, is published in an accompanying paper.

  2. Lymnaea cousini Jousseaume, 1887, from Ecuador (Gastropoda: Lymnaeidae

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    W. Lobato Paraense

    1995-10-01

    Full Text Available A description is given of the shell, renal organ, reproductive system and radula of topotypic specimens of Lymnaea cousini Jousseaume, 1887. A diagnosis between it and four other lymnaeids which also occur in South America and were previously studied by the author (L. columella, L. diaphana, L. viatrix and L. rupestris is presented.

  3. The phylogeography of Indoplanorbis exustus (Gastropoda: Planorbidae in Asia

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    Diaz Jose L

    2010-07-01

    Full Text Available Abstract Background The freshwater snail Indoplanorbis exustus is found across India, Southeast Asia, central Asia (Afghanistan, Arabia and Africa. Indoplanorbis is of economic importance in that it is responsible for the transmission of several species of the genus Schistosoma which infect cattle and cause reduced livestock productivity. The snail is also of medical importance as a source of cercarial dermatitis among rural workers, particularly in India. In spite of its long history and wide geographical range, it is thought that Indoplanorbis includes only a single species. The aims of the present study were to date the radiation of Indoplanorbis across Asia so that the factors involved in its dispersal in the region could be tested, to reveal potential historical biogeographical events shaping the phylogeny of the snail, and to look for signs that I. exustus might be polyphyletic. Results The results indicated a radiation beginning in the late Miocene with a divergence of an ancestral bulinine lineage into Assam and peninsular India clades. A Southeast Asian clade diverged from the peninsular India clade late-Pliocene; this clade then radiated at a much more rapid pace to colonize all of the sampled range of Indoplanorbis in the mid-Pleistocene. Conclusions The phylogenetic depth of divergences between the Indian clades and Southeast Asian clades, together with habitat and parasitological differences suggest that I. exustus may comprise more than one species. The timescale estimated for the radiation suggests that the dispersal to Arabia and to Southeast Asia was facilitated by palaeogeographical events and climate change, and did not require human involvement. Further samples from Afghanistan, Africa and western India are required to refine the phylogeographical hypothesis and to include the African Recent dispersal.

  4. Sobre dos Cassiopidae (Gastropoda del Neocomiense español.

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    MENNESSIER, G., CALZADA, S.

    1985-01-01

    Full Text Available Se describen 2 gasterópodos neocomienses (Cretácico Inferior, provenientes del Weald de Cameros. Uno de ellos, Paraglauconia vierai se considera nueva especie. El otro es una especie descrita hace poco en el Hauteriviense francés.

  5. The radular morphology of Nassariidae (Gastropoda:Caenogastropoda) from China

    Institute of Scientific and Technical Information of China (English)

    YANG Jingwen; ZHANG Suping

    2011-01-01

    The family Nassariidae includes a number of species that are distributed throughout the world.Each species has a characteristic shell shape,tooth shape,and behavior.However,the classification of species in this family of the Rhachiglossa is controversial.We describe the radulae of 22 species from China in detail using optical and scanning electron microscopy.These species are considered to be representatives of two subfamilies,two genera,and 10 subgenera.Our results suggest that the morphology of the central tooth and the pair of lateral teeth and the presence or absence of a pair of intermediate accessory lateral teeth could be used to distinguish among species.We found no support for the subgeneric differentiation of the species.However,the presence or absence of the intermediate lateral accessory plate was characteristic of species divisions.We noted sexual dimorphism in the shape of the teeth in some species,and considerable variability of the shape of teeth within a single species.Based on our results,the genus Nassarius cannot be split into subgenera using radula morphology.

  6. Phylogenetics, development, and Cenozoic paleontology of Buccinidae (Mollusca:Gastropoda)

    OpenAIRE

    2009-01-01

    The buccinid gastropods (family Buccinidae) are a species-rich clade of mostly North Pacific taxa with an abundant fossil record that dates to the Cretaceous. Here, the evolution, systematics, and biology of fossil and extant members of this family are treated using a variety of analytical and methodological approaches. In chapter one, a new fossil species of Bruclarkia, an endemic eastern Pacific buccinid from the Eocene, Oligocene, and Miocene, is described from the Astoria Formation of the...

  7. Familia Ellobiidae (Gastropoda: Archaeopulmonata en el litoral peruano

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    Carlos Paredes

    2013-05-01

    Full Text Available Se reportan 8 especies de Ellobiidae para la Costa Peruana, pertenecientes a las subfamilias Ellobiinae: Ellobium stagnale (Orbigny, 1835 y Sarnia frumentum Petit, 1842; Melampodinae: Melampus carolianus (Lesson, 1842, Melampus olivaceus Carpenter, 1857 y Detracia graminea Morrison, 1846; y Pedipedinae: Marinula acuta (Orbigny, 1835, Marinula concinna (C.B Adams, 1852 y Marinula pepita King, 1831. Seis especies viven asociadas al bosque de manglar en el departamento de Tumbes, y dos en las playas de canto rodado en los límites de la Provincia Peruana. Cuatro especies tropicales se registran por primera vez para el mar peruano: E. stagnale, M. olivaceus, D. graminea y M. acuta.

  8. Biomphalaria prona (Gastropoda: Planorbidae: a morphological and biochemical study

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    W. Lobato Paraense

    1992-06-01

    Full Text Available Two samples of Biomphalaria prona (Martens, 1873 from Lake Valencia (type locality and seven from other Venezuelan localities were studied morphologically (shell and reproductive system and biochemically (allozyme electrophoresis. In spite of marked differences in shell characters, all of them proved indistinguishable under the anatomic and biochemical criteria. So far B. prona has been considered an endemic species, restricted to Lake Valencia. It is now demonstrated that the extralacustrine populations refered to Biomphalaria havanensis (Pfeiffer, 1839 by several authors correspond in shell characters to an extreme variant of B. prona from the Lake and really belong to the last*mentioned species. They may be regarded as the result of a process of directional selection favoring a shell phenotype other than those making up the modal class in the Lake.

  9. New species of Cyclodontina from Bahia, Brazil (Gastropoda, Pulmonata, Odontostomidae

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    Rodrigo B. Salvador

    2014-12-01

    Full Text Available A new species of pulmonate snail was recently collected in a small forest fragment in the city of Bom Jesus da Lapa, Bahia state, Brazil. Bahia is known for a high diversity of land snails and Bom Jesus da Lapa is an interesting locality, since it is close to the interface between two major Brazilian biomes: Cerrado and Caatinga. The new species is described as Cyclodontina tapuia sp. nov. and can be easily identified by its brown shell, conical spire, convex whorls, a sculpture comprised of strong ribs, and an aperture with four barriers: a median parietal tooth, a median palatal tooth, a median basal tooth and a strong columellar lamella. This discovery is also a reminder of how little the Brazilian continental molluscan fauna is known and of the urgency in studying and preserving the rich (though usually overlooked fauna of the Caatinga.

  10. On relict hydrobiid species in Brazilian Amazonia (Gastropoda, Prosobranchia, Hydrobiidae)

    NARCIS (Netherlands)

    Wesselingh, F.P.

    2000-01-01

    Two extant hydrobiid species from the lower Tapajos river of Brazil are redescribed. Potamopyrgus amazonicus Haas, 1949, is assigned to the genus Dyris Conrad, 1871. At least eleven species from Miocene deposits of Western Amazonia are assigned to Dyris, a genus that was previously assumed to be ext

  11. Hydrocarbons in the land snail Cepaea nemoralis (L.) (gastropoda, pulmonata)

    NARCIS (Netherlands)

    Horst, D.J. van der; Oudejans, R.C.H.M.

    1972-01-01

    1. 1. The biosynthesis of hydrocarbons in the snail Cepaea nemoralis was studied after injection of the 14C-labelled precursors acetate, valine, isoleucine and palmitic acid. 2. 2. The highest incorporation was achieved with palmitic acid, although with the other precursors the hydrocarbons were al

  12. Recharacterization of Synapterpes (S. hanleyi (Pfeiffer (Mollusca, Gastropoda, Stylommatophora, Subulinidae

    Directory of Open Access Journals (Sweden)

    Norma Campos Salgado

    1999-01-01

    Full Text Available Synapterpes (S. hanleyi (Pfeiffer, 1846 is characterized by anatomy, synonymy and geographical distribution. Shell and soft parts were studied and important taxonomic characters evaluated and illustrated. These studies give conditions to characterize the species and include it in the genus Synapterpes Pilsbry, 1896 and distinguish S. hanleyi from the other species of Synapterpes s.s. known only by their shells, respectively from Brazil and Colombia: S.(S. coronatus (Pfeiffer, 1846 and S.(S. wallisi (Mousson, 1869.

  13. The Genus Theba (Mollusca: Gastropoda: Helicidae), Systematics and Distribution

    NARCIS (Netherlands)

    Gittenberger, E.; Ripken, Th. E.J.

    1987-01-01

    Our knowledge concerning taxonomy and zoogeography of the fossil and recent species of the helicid genus Theba is summarized and enlarged. The fossil T. arinagae spec. nov. is described from Gran Canaria. The recent T. andalusica spec. nov. and T. sacchii spec. nov. are described from the southernmo

  14. Permanent genetic resources added to Molecular Ecology Resources Database 1 December 2010-31 January 2011.

    Science.gov (United States)

    Agata, Kiyokazu; Alasaad, Samer; Almeida-Val, Vera Maria Fonseca; Alvarez-Dios, J A; Barbisan, F; Beadell, Jon S; Beltrán, J F; Benítez, M; Bino, G; Bleay, Colin; Bloor, P; Bohlmann, Jörg; Booth, Warren; Boscari, E; Caccone, Adalgisa; Campos, Tatiana; Carvalho, B M; Climaco, Gisele Torres; Clobert, Jean; Congiu, L; Cowger, Christina; Dias, G; Doadrio, I; Farias, Izeni Pires; Ferrand, N; Freitas, Patrícia D; Fusco, G; Galetti, Pedro M; Gallardo-Escárate, Cristian; Gaunt, Michael W; Ocampo, Zaneli Gomez; Gonçalves, H; Gonzalez, E G; Haye, Pilar; Honnay, O; Hyseni, Chaz; Jacquemyn, H; Jowers, Michael J; Kakezawa, Akihiro; Kawaguchi, Eri; Keeling, Christopher I; Kwan, Ye-Seul; La Spina, Michelangelo; Lee, Wan-Ok; Leśniewska, M; Li, Yang; Liu, Haixia; Liu, Xiaolin; Lopes, S; Martínez, P; Meeus, S; Murray, Brent W; Nunes, Aline G; Okedi, Loyce M; Ouma, Johnson O; Pardo, B G; Parks, Ryan; Paula-Silva, Maria Nazaré; Pedraza-Lara, C; Perera, Omaththage P; Pino-Querido, A; Richard, Murielle; Rossini, Bruno C; Samarasekera, N Gayathri; Sánchez, Antonio; Sanchez, Juan A; Santos, Carlos Henrique Dos Anjos; Shinohara, Wataru; Soriguer, Ramón C; Sousa, Adna Cristina Barbosa; Sousa, Carolina Fernandes Da Silva; Stevens, Virginie M; Tejedo, M; Valenzuela-Bustamante, Myriam; Van de Vliet, M S; Vandepitte, K; Vera, M; Wandeler, Peter; Wang, Weimin; Won, Yong-Jin; Yamashiro, A; Yamashiro, T; Zhu, Changcheng

    2011-05-01

    This article documents the addition of 238 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Alytes dickhilleni, Arapaima gigas, Austropotamobius italicus, Blumeria graminis f. sp. tritici, Cobitis lutheri, Dendroctonus ponderosae, Glossina morsitans morsitans, Haplophilus subterraneus, Kirengeshoma palmata, Lysimachia japonica, Macrolophus pygmaeus, Microtus cabrerae, Mytilus galloprovincialis, Pallisentis (Neosentis) celatus, Pulmonaria officinalis, Salminus franciscanus, Thais chocolata and Zootoca vivipara. These loci were cross-tested on the following species: Acanthina monodon, Alytes cisternasii, Alytes maurus, Alytes muletensis, Alytes obstetricans almogavarii, Alytes obstetricans boscai, Alytes obstetricans obstetricans, Alytes obstetricans pertinax, Cambarellus montezumae, Cambarellus zempoalensis, Chorus giganteus, Cobitis tetralineata, Glossina fuscipes fuscipes, Glossina pallidipes, Lysimachia japonica var. japonica, Lysimachia japonica var. minutissima, Orconectes virilis, Pacifastacus leniusculus, Procambarus clarkii, Salminus brasiliensis and Salminus hilarii.

  15. Call intercalation in dyadic interactions in natural choruses of Johnstone's whistling frog Eleutherodactylus johnstonei (Anura: Eleutherodactylidae).

    Science.gov (United States)

    Tárano, Zaida; Carballo, Luisana

    2016-05-01

    Communal signaling increases the likelihood of acoustic interference and impairs mate choice; consequently, mechanisms of interference avoidance are expected. Adjustment of the timing of the calls between signalers, specifically call alternation, is probably the most efficient strategy. For this reason, in the present study we analyzed call timing in dyads of males of E. johnstonei in six natural assemblages. We addressed whether males entrain their calls with those of other males at the assemblage and if they show selective attention in relation to perceived amplitude of the other males' calls, inter-male distance, or intrinsic call features (call duration, period or dominant frequency). We expected males to selectively attend to closer or louder males and/or to those of higher or similar attractiveness for females than themselves, because those would be their strongest competitors. We found that most males intercalated their calls with those of at least one male. In assemblages of 3 individuals, males seemed to attend to a fixed number of males regardless of their characteristics. In assemblages of more than 3 individuals, the perceived amplitude of the call of the neighboring male was higher, and the call periods of the males were more similar in alternating dyads than in the non-alternating ones. At the proximate level, selective attention based on perceived amplitude may relate to behavioral hearing thresholds. Selective attention based on the similarity of call periods may relate to the properties of the call oscillators controlling calling rhythms. At the ultimate level, selective attention may be related to the likelihood of acoustic competition for females.

  16. Quantifying the spatiotemporal dynamics in a chorus frog (Pseudacris) hybrid zone over 30 years.

    Science.gov (United States)

    Engebretsen, Kristin N; Barrow, Lisa N; Rittmeyer, Eric N; Brown, Jeremy M; Moriarty Lemmon, Emily

    2016-07-01

    Although theory suggests that hybrid zones can move or change structure over time, studies supported by direct empirical evidence for these changes are relatively limited. We present a spatiotemporal genetic study of a hybrid zone between Pseudacris nigrita and P. fouquettei across the Pearl River between Louisiana and Mississippi. This hybrid zone was initially characterized in 1980 as a narrow and steep "tension zone," in which hybrid populations were inferior to parentals and were maintained through a balance between selection and dispersal. We reanalyzed historical tissue samples and compared them to samples of recently collected individuals using microsatellites. Clinal analyses indicate that the cline has not shifted in roughly 30 years but has widened significantly. Anthropogenic and natural changes may have affected selective pressure or dispersal, and our results suggest that the zone may no longer best be described as a tension zone. To the best of our knowledge, this study provides the first evidence of significant widening of a hybrid cline but stasis of its center. Continued empirical study of dynamic hybrid zones will provide insight into the forces shaping their structure and the evolutionary potential they possess for the elimination or generation of species.

  17. Accumulation of pesticides in Pacific chorus frogs (Pseudacris regilla) from California's Sierra Nevada Mountains, USA.

    Science.gov (United States)

    Smalling, Kelly L; Fellers, Gary M; Kleeman, Patrick M; Kuivila, Kathryn M

    2013-09-01

    Pesticides are receiving increasing attention as potential causes of amphibian declines, acting singly or in combination with other stressors, but limited information is available on the accumulation of current-use pesticides in tissue. The authors examined potential exposure and accumulation of currently used pesticides in pond-breeding frogs (Pseudacris regilla) collected from 7 high elevations sites in northern California. All sites sampled are located downwind of California's highly agricultural Central Valley and receive inputs of pesticides through precipitation and/or dry deposition. Whole frog tissue, water, and sediment were analyzed for more than 90 current-use pesticides and pesticide degradates using gas chromatography-mass spectrometry. Two fungicides, pyraclostrobin and tebuconazole, and one herbicide, simazine, were the most frequently detected pesticides in tissue samples. Median pesticide concentration ranged from 13 µg/kg to 235 µg/kg wet weight. Tebuconazole and pyraclostrobin were the only 2 compounds observed frequently in frog tissue and sediment. Significant spatial differences in tissue concentration were observed, which corresponded to pesticide use in the upwind counties. Data generated indicated that amphibians residing in remote locations are exposed to and capable of accumulating current-use pesticides. A comparison of P. regilla tissue concentrations with water and sediment data indicated that the frogs are accumulating pesticides and are potentially a more reliable indicator of exposure to this group of pesticides than either water or sediment.

  18. Notes on a Visit to Nagasaki by Beijing Yuying Beiman Alumni Specialists Chorus

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>At the invitation of the Nagasaki Municipal Government, the Nagasaki International Tourism and Convention Association and the Executive Committee of Madame Butterfly International Concours in Nagasaki

  19. Accumulation of pesticides in pacific chorus frogs (Pseudacris regilla) from California's Sierra Nevada Mountains, USA

    Science.gov (United States)

    Smalling, Kelly L.; Fellers, Gary M.; Kleeman, Patrick M.; Kuivila, Kathryn

    2013-01-01

    Pesticides are receiving increasing attention as potential causes of amphibian declines, acting singly or in combination with other stressors, but limited information is available on the accumulation of current-use pesticides in tissue. The authors examined potential exposure and accumulation of currently used pesticides in pond-breeding frogs (Pseudacris regilla) collected from 7 high elevations sites in northern California. All sites sampled are located downwind of California's highly agricultural Central Valley and receive inputs of pesticides through precipitation and/or dry deposition. Whole frog tissue, water, and sediment were analyzed for more than 90 current-use pesticides and pesticide degradates using gas chromatography–mass spectrometry. Two fungicides, pyraclostrobin and tebuconazole, and one herbicide, simazine, were the most frequently detected pesticides in tissue samples. Median pesticide concentration ranged from 13 µg/kg to 235 µg/kg wet weight. Tebuconazole and pyraclostrobin were the only 2 compounds observed frequently in frog tissue and sediment. Significant spatial differences in tissue concentration were observed, which corresponded to pesticide use in the upwind counties. Data generated indicated that amphibians residing in remote locations are exposed to and capable of accumulating current-use pesticides. A comparison of P. regilla tissue concentrations with water and sediment data indicated that the frogs are accumulating pesticides and are potentially a more reliable indicator of exposure to this group of pesticides than either water or sediment.

  20. The Effects of Land-Use Change from Grassland to Miscanthus x giganteus on Soil N2O Emissions

    Directory of Open Access Journals (Sweden)

    Michael Williams

    2013-09-01

    Full Text Available A one year field trial was carried out on three adjacent unfertilised plots; an 18 year old grassland, a 14 year old established Miscanthus crop, and a 7 month old newly planted Miscanthus crop. Measurements of N2O, soil temperature, water filled pore space (WFPS, and inorganic nitrogen concentrations, were made every one to two weeks. Soil temperature, WFPS and NO3− and NH4+ concentrations were all found to be significantly affected by land use. Temporal crop effects were also observed in soil inorganic nitrogen dynamics, due in part to C4 litter incorporation into the soil under Miscanthus. Nonetheless, soil N2O fluxes were not significantly affected by land use. Cumulative yearly N2O fluxes were relatively low, 216 ± 163, 613 ± 294, and 377 ± 132 g·N·ha−1·yr−1 from the grassland, newly planted Miscanthus, and established Miscanthus plots respectively, and fell within the range commonly observed for unfertilised grasslands dominated by perennial ryegrass (Lolium perenne. Higher mean cumulative fluxes were measured in the newly planted Miscanthus, which may be linked to a possible unobserved increase immediately after establishment. However, these differences were not statistically significant. Based on the results of this experiment, land-use change from grassland to Miscanthus will have a neutral impact on medium to long-term N2O emissions.

  1. Genetic variation in Miscanthus x giganteus and the importance of estimating genetic distance tresholds for differentiating clones

    DEFF Research Database (Denmark)

    Glowacka, K; Clark, L; Adhikari, S;

    2015-01-01

    with samples of the parental species M. sacchariflorus and M. sinensis. Estimates of genotyping error rates were essential for distinguishing between experimental error and true genotypic differences among accessions. Given differences in estimated error rates and costs per marker for SSRs and RAD......-seq, the former is currently more cost-effective for determining if two accessions are genetically identical. We concluded that all of the Mxg legacy cultivars were derived via vegetative propagation from a single genet. In contrast with the Mxg legacy cultivars, genetic similarity to the type-specimen of eight...... new triploid Mxg progeny ranged from 0.46 to 0.56. Though genetic diversity among the Mxg legacy cultivars is critically low, new crosses can provide much-needed variation to growers...

  2. Evaluation of the use of Olivella minuta (Gastropoda, Olividae) and Hastula cinerea (Gastropoda, Terebridae) as TBT sentinels for sandy coastal habitats.

    Science.gov (United States)

    Petracco, Marcelo; Camargo, Rita Monteiro; Berenguel, Thayana Amorim; de Arruda, Noelle C L Patrício; del Matto, Lygia A; Amado, Lílian Lund; Corbisier, Thais Navajas; Castro, Ítalo Braga; Turra, Alexander

    2015-07-01

    Tributyltin (TBT) contamination is still recorded in the environment even after its ban in antifouling paints. Since most biomonitors of TBT contamination, through imposex evaluation, are hard-bottom gastropods, the identification of soft-bottom sentinels has become useful for regions where rocky shores and coral reefs are absent. Thus, an evaluation of Olivella minuta and Hastula cinerea as monitors of TBT contamination was performed in two sandy beaches located under influence area of São Sebastião harbor (São Paulo state, Brazil), where previous and simultaneous studies have reported environmental contamination by TBT. In addition, the imposex occurrence in H. cinerea was assessed in an area with low marine traffic (Una beach), also located in São Paulo State. A moderate imposex incidence in O. minuta was detected in Pernambuco (% I = 9.36, RPLI = 4.49 and RPLIstand = 4.27) and Barequeçaba (% I = 2.42, RPLI = 0.36 and RPLIstand = 0.81) beaches, indicating TBT contamination. In contrast, more severe levels of imposex were recorded for H. cinerea in Una beach (% I = 12.45) and mainly in Barequeçaba beach (% I = 98.92, RPLI = 26.65). Our results suggest that O. minuta and H. cinerea have good potential as biomonitors for TBT based on their wide geographical distribution, common occurrence in different coastal sediment habitats, easy collection, and association with TBT-contaminated sediments.

  3. Histologia das glândulas salivares dos Limacoidea e Milacidae (Gastropoda, Pulmonata Histology of the salivary glands of the Limacoidea and Milacidae (Gastropoda, Pulmonata

    Directory of Open Access Journals (Sweden)

    Ana Maria Leal-Zanchet

    2003-09-01

    Full Text Available The histology of the salivary glands of six species of Limacoidea, Boettgerilla pallens Simroth, 1912, Deroceras laeve (Müller, 1774, Deroceras reticulatum (Müller, 1774, Deroceras rodnae Grossu & Lupu, 1965, Malacolimax tenellus (Müller, 1774 and Lehmannia marginata (Müller, 1774, and a species of Milacidae, Tandonia budapestensis (Hazay, 1881 is comparatively described herein. In the glandular parenchyme four to five secretory cell types are distinguished and characterised, besides a cell type which is probably undifferentiated. The secretory cell types are classified into two groups, mucous and serous cells. Two types of mucous cells and two to three types of serous cells are distinguished. The salivary glands of the herein studied Limacoidea and Milacidae show a duct system composed of intralobular, interlobular and main ducts, each one presenting a characteristic type of epithelial lining. The results are comparatively discussed with the data available in the literature, in order to verify the correspondence between the different cell types described for other Pulmonata.

  4. Development of a new sediment bioassay with the freshwater mudsnail Potamopyrgus antipodarum (Gastropoda: Prosobranchia); Entwicklung eines Sedimentbiotests mit der Zwergdeckelschnecke Potamopyrgus antipodarum (Gastropoda: Prosobranchia)

    Energy Technology Data Exchange (ETDEWEB)

    Duft, M.; Tillmann, M.; Markert, B. [Internationales Hochschulinstitut Zittau (Germany). Lehrstuhl Umweltverfahrenstechnik; Schulte-Oehlmann, U.; Oehlmann, J. [Frankfurt Univ. (Germany). Zoologisches Inst.

    2002-07-01

    Currently, only few organismic biotest systems are available for the assessment of effects on reproduction, which consider an exposure toward whole sediments. A well-suited test organism is the parthenogenetic mudsnail Potamopyrgus antipodarum. This ovoviviparous prosobranch snail lives in the upper layers of freshwater and brackish sediments. The number of (unshelled) embryos turned out to be a very sensitive parameter for the indication of sediment components affecting reproduction. Additionally, this endpoint allows to signal possible estrogenic sediment compounds. With this 28-day bioassay, laboratory tests on the effects of various chemicals on P. antipodarum were performed, e.g. triphenyltin and bisphenol A, in relevant environmental concentration ranges. Furthermore, the suitability of our test system for the investigation of complex and multiple level ranged contaminations was examined by means of various natural sediments from the Neisse and Odra rivers. (orig.) [German] Derzeit bestehen nur wenige etablierte organismische Testverfahren zur Erfassung von reproduktionstoxischen Effekten, die eine Exposition gegenueber Gesamtsedimenten beruecksichtigen. Ein hierfuer gut geeigneter Testorganismus ist die parthenogenetische Zwergdeckelschnecke Potamopyrgus antipodarum. Sie gehoert zu den ovoviviparen (lebendgebaerenden) Prosobranchiern und lebt in den obersten Schichten von Suess- und Brackwassersedimenten. Als empfindlicher Parameter zur Indikation reproduktionstoxisch wirkender Sedimentkomponenten erwies sich die Anzahl der (neugebildeten) Embryonen im Brutraum - dieser Endpunkt vermag zudem auf eventuell vorhandene oestrogene Wirkstoffe im Sediment hinzuweisen. Mit Hilfe dieses 28 Tage umfassenden Biotests wurden in Laboruntersuchungen die Wirkungen verschiedener Umweltchemikalien, wie z.B. Triphenylzinn und Bisphenol A, auf P. antipodarum in umweltrelevanten Konzentrationsreihen getestet. Darueber hinaus wurde die Eignung des Biotests fuer die Ermittlung und Untersuchung der Wirkung komplexer Kontaminanten anhand von verschiedenen realen Flusssedimenten unterschiedlichen Belastungsgrades - aus Neisse und Oder - erprobt. (orig.)

  5. Foraminiferans as food for Cephalaspideans (Gastropoda: Opisthobranchia), with notes on secondary tests around calcareous foraminiferans

    DEFF Research Database (Denmark)

    Cedhagen, Tomas

    1996-01-01

    species, Ammonia batavus and two agglutinating species, Ammoscalaria pseudospiralis and Ammotium cassis. The test (shell) material of the latter two species was sand grains (quartz). It was inferred that the gastropods avoid agglutinating foraminiferans as food. Many calcareous but not agglutinating...... purposes. It might, in species like Ammonia batavus, have become a kind of antipredatory device or mimicry. A predator might conceive such a species as an agglutinating species and neglect it. The secondary test is a delicate structure in most species and is easily destroyed by the rough sampling...

  6. Vitrinellidae (Marine Mollusca Gastropoda) from Holocene deposits in Surinam (Dutch Guiana)

    NARCIS (Netherlands)

    Regteren Altena, van C.O.

    1966-01-01

    Five species of Vitrinellidae have been found in the Holocene shell ridges of Surinam. Of these, Vitrinella (Striovitrinella) cupidinensis,Cochliolepis surinamensis, and Solariorbis guianensis are new species, while Cyclostremiscus caraboboensis Weisbord is known from Pliocene beds in Venezuela and

  7. Milax Clerxi nov. spec., eine neue Nacktschnecke aus Südjugoslawien (Gastropoda, Pulmonata, Milacidae)

    NARCIS (Netherlands)

    Rähle, W.

    1977-01-01

    Durch das Entgegenkommen von Herrn Dr. C. O. van Regteren Altena, Leiden, erhielt der Verfasser eine Serie juveniler, fast erwachsener und erwachsener Nacktschnecken aus der Gattung Milax zur Bearbeitung, welche aus der Umgebung der Stadt Ohrid in Mazedonien stammen und dort im Sommer 1974 von Drs.

  8. Pseudo-imposex: male features in female volutes not TBT-induced (Gastropoda: Volutidae)

    NARCIS (Netherlands)

    Swennen, C.; Horpet, P.

    2008-01-01

    The occurrence of a penis in female gastropods of the superfamily Muricoidea (infraorder Neogastropoda) has commonly been accepted as an indicator of tributyltin (TBT) pollution. Some species seem less sensitive than others, and one belonging to the family Columbellidae has been reported that it lac

  9. Mitochondrial DNA hyperdiversity and its potential causes in the marine periwinkle Melarhaphe neritoides (Mollusca: Gastropoda)

    Science.gov (United States)

    Mardulyn, Patrick; Hardy, Olivier J.; Jordaens, Kurt; de Frias Martins, António Manuel; Backeljau, Thierry

    2016-01-01

    We report the presence of mitochondrial DNA (mtDNA) hyperdiversity in the marine periwinkle Melarhaphe neritoides (Linnaeus, 1758), the first such case among marine gastropods. Our dataset consisted of concatenated 16S-COI-Cytb gene fragments. We used Bayesian analyses to investigate three putative causes underlying genetic variation, and estimated the mtDNA mutation rate, possible signatures of selection and the effective population size of the species in the Azores archipelago. The mtDNA hyperdiversity in M. neritoides is characterized by extremely high haplotype diversity (Hd = 0.999 ± 0.001), high nucleotide diversity (π = 0.013 ± 0.001), and neutral nucleotide diversity above the threshold of 5% (πsyn = 0.0677). Haplotype richness is very high even at spatial scales as small as 100m2. Yet, mtDNA hyperdiversity does not affect the ability of DNA barcoding to identify M. neritoides. The mtDNA hyperdiversity in M. neritoides is best explained by the remarkably high mutation rate at the COI locus (μ = 5.82 × 10−5 per site per year or μ = 1.99 × 10−4 mutations per nucleotide site per generation), whereas the effective population size of this planktonic-dispersing species is surprisingly small (Ne = 5, 256; CI = 1,312–3,7495) probably due to the putative influence of selection. Comparison with COI nucleotide diversity values in other organisms suggests that mtDNA hyperdiversity may be more frequently linked to high μ values and that mtDNA hyperdiversity may be more common across other phyla than currently appreciated. PMID:27761337

  10. On Cyprian Helicellinae (Mollusca: Gastropoda Pulmonata: Helicidae), making a new start

    NARCIS (Netherlands)

    Gittenberger, E.

    1991-01-01

    Our fragmentary knowledge concerning the Cyprian Helicellinae is revised and summarized, while new data are added. "Helicella (Xerotricha) conspurcata distinguenda" Haas, 1936, is a Helicopsis species that has to be called H. cypriola (Westerlund, 1889) as a consequence of the selection of a neotype

  11. Molecular identification of Austrobilharzia species parasitizing Cerithidea cingulata (Gastropoda: Potamididae) from Kuwait Bay.

    Science.gov (United States)

    Al-Kandari, W Y; Al-Bustan, S A; Isaac, A M; George, B A; Chandy, B S

    2012-12-01

    Avian schistosomes belonging to the genus Austrobilharzia (Digenea: Schistosomatidae) are among the causative agents of cercarial dermatitis in humans. In this paper, ribosomal and mitochondrial DNA sequences were used to study schistosome cercariae from Kuwait Bay that have been identified morphologically as Austrobilharzia sp. Sequence comparison of the ribosomal DNA (rDNA) 28S and 18S regions of the collected schistosome cercariae with corresponding sequences of other schistosomes in GenBank revealed high sequence similarity. This confirmed the morphological identification of schistosome cercariae from Kuwait Bay as belonging to the genus Austrobilharzia. The finding was further supported by the phylogenetic tree that was constructed based on the combined data set 18S-28S-mitochondrial cytochrome oxidase I (mtCO1) sequences in which Austrobilharzia sp. clustered with A. terrigalensis and A. variglandis. Sequence comparison of the Austrobilharzia sp. from Kuwait Bay with A. variglandis and A. terrigalensis based on mtCO1 showed a variation of 10% and 11%, respectively. Since the sequence variation in the mtCO1 was within the interspecific range among trematodes, it seems that the Austrobilharzia species from Kuwait Bay is different from the two species reported in GenBank, A. terrigalensis and A. variglandis.

  12. A revision of Cerithidea (Cerithideopsilla) cingulata (Gmelin) and some related species (Mollusca, Gastropoda)

    NARCIS (Netherlands)

    Regteren Altena, van C.O.

    1940-01-01

    INTRODUCTION Engaged in the study of fossil shells belonging to Thiele's sectio Cerithideopsilla of the genus Cerithidea Swainson and deriving from plio-pleistocene beds in East Java, I failed to find a satisfying account on the recent species of this group. Therefore I resolved to examine as large

  13. Neuromuscular development of Aeolidiella stephanieae Valdéz, 2005 (Mollusca, Gastropoda, Nudibranchia)

    DEFF Research Database (Denmark)

    Kristof, Alen; Klussmann-Kolb, Annette

    2010-01-01

    ABSTRACT: BACKGROUND: Studies on the development of the nervous system and the musculature of invertebrates have become more sophisticated and numerous within the last decade and have proven to provide new insights into the evolutionary history of organisms. In order to provide new morphogenetic ...

  14. Not so sluggish: the success of the Felimare picta complex (Gastropoda, Nudibranchia crossing Atlantic biogeographic barriers

    Directory of Open Access Journals (Sweden)

    Frederico Almada

    2016-01-01

    Full Text Available The molecular phylogeny of the Atlanto-Mediterranean species of the genus Felimare, particularly those attributed to the species F. picta, was inferred using two mitochondrial markers (16S and COI. A recent revision of the Chromodorididae clarified the taxonomic relationships at the family level redefining the genus Felimare. However, conflicting taxonomic classifications have been proposed for a restrict group of taxa with overlapping morphological characteristics and geographical distributions designated here as the Felimare picta complex. Three major groups were identified: one Mediterranean and amphi-Atlantic group; a western Atlantic group and a tropical eastern Atlantic group. F. picta forms a paraphyletic group since some subspecies are more closely related with taxa traditionaly classified as independent species (e.g. F. zebra than with other subspecies with allopatric distributions (e.g. F. picta picta and F. picta tema. Usually, nudibranchs have adhesive demersal eggs, short planktonic larval phases and low mobility as adults unless rafting on floating materials occurs. Surprisingly however, the phylogeny of the F. picta complex suggests that they successfully cross main Atlantic biogeographic barriers including the mid-Atlantic barrier. This ability to cross different biogeographic barriers may be related to F. picta’s distinct life history and ecological traits. Compared to other Chromodorididae F. picta has larger eggs and planktotrophic larvae which could be related to a longer planktonic phase.

  15. A new species of Nassarius (Gastropoda: Nassariidae) from the western Pacific Ocean

    Institute of Scientific and Technical Information of China (English)

    ZHANG Suping

    2013-01-01

    This paper describes a new species of Nassarius from the South China Sea,which was recognized when re-sorting the collection of Nassariidae in the Marine Biological Museum,Chinese Academy of Sciences,Qingdao,China.The shells were collected during several investigations,including the National Comprehensive Oceanic Survey in 1958-1959,and the China-Vietnam Co-Investigation on Marine Resource of the Beibu Gulf during 1959-1962.The morphology of the shell and the radula places the new species of Nassarius within the subgenus Zeuxis.It is named Nassarius (Zeuxis) nanhaiensis sp.nov.

  16. Caribbean Bulimulus revisited: physical moves and molecular traces (Mollusca, Gastropoda, Bulimulidae

    Directory of Open Access Journals (Sweden)

    Abraham S.H. Breure

    2016-03-01

    Full Text Available Twenty-five samples of Bulimulus species are studied, partly from localities within their known distribution range, partly based on interceptions where the material originates from localities where the species seem to be recently introduced and non-native. Molecular study of cytochrome oxidase 1 (CO1 reveals the origin of some of these introductions, but is less conclusive for others. Four different methods for species delimitation were applied, which did not result in unambiguous species hypotheses. For a rapid identification of morphologically indistinct species, a more comprehensive database of sequences is needed.

  17. Gymnodoris pattani, a new dorid nudibranch from Pattani Bay, Gulf of Thailand (Gastropoda, Nudibranchia)

    NARCIS (Netherlands)

    Swennen, C.

    1996-01-01

    Several specimens of a new dorid nudibranch have been found in Yaring River, Pattani Province in southern Thailand. The species clearly belongs to the genus Gymnodoris, and is described and named G. pattani. It can be distinguished from all other species described in the genus by its translucently g

  18. Sense organs in Spongiobranchaea australis d’Orbigny, 1835 (Gastropoda, Pteropoda)

    NARCIS (Netherlands)

    Spoel, van der S.

    1964-01-01

    The sense organs: the labial tentacles, eyes, rhinophores, osphradium and statocysts of Spongiobranchaea australis d’Orbigny, 1835 are described together with their innervation. The descriptions are based on serial sections of three animals.

  19. The aquatic molluscs (Mollusca: Gastropoda and Bivalvia of Vrachanski Balkan Nature Park

    Directory of Open Access Journals (Sweden)

    DILIAN GEORGIEV

    2016-05-01

    Full Text Available Till now 13 species of aquatic molluscs are known to inhabit the park area: 11 species of snails and 2 species of clams. Even included in the list the species of Grossuana and Radix balthica has to be studied anatomically for sure identification. Nine species are of conservation statute classified as "Least Concern" or "Vulnerable", and four does not have any statute. Three stygobiotic snail species are local endemics.

  20. Mitochondrial DNA hyperdiversity and its potential causes in the marine periwinkle Melarhaphe neritoides (Mollusca: Gastropoda

    Directory of Open Access Journals (Sweden)

    Séverine Fourdrilis

    2016-10-01

    Full Text Available We report the presence of mitochondrial DNA (mtDNA hyperdiversity in the marine periwinkle Melarhaphe neritoides (Linnaeus, 1758, the first such case among marine gastropods. Our dataset consisted of concatenated 16S-COI-Cytb gene fragments. We used Bayesian analyses to investigate three putative causes underlying genetic variation, and estimated the mtDNA mutation rate, possible signatures of selection and the effective population size of the species in the Azores archipelago. The mtDNA hyperdiversity in M. neritoides is characterized by extremely high haplotype diversity (Hd = 0.999 ± 0.001, high nucleotide diversity (π = 0.013 ± 0.001, and neutral nucleotide diversity above the threshold of 5% (πsyn = 0.0677. Haplotype richness is very high even at spatial scales as small as 100m2. Yet, mtDNA hyperdiversity does not affect the ability of DNA barcoding to identify M. neritoides. The mtDNA hyperdiversity in M. neritoides is best explained by the remarkably high mutation rate at the COI locus (μ = 5.82 × 10−5 per site per year or μ = 1.99 × 10−4 mutations per nucleotide site per generation, whereas the effective population size of this planktonic-dispersing species is surprisingly small (Ne = 5, 256; CI = 1,312–3,7495 probably due to the putative influence of selection. Comparison with COI nucleotide diversity values in other organisms suggests that mtDNA hyperdiversity may be more frequently linked to high μ values and that mtDNA hyperdiversity may be more common across other phyla than currently appreciated.

  1. Chondrina tatrica Ložek, 1948: new species for the Romanian fauna (Gastropoda: Chondrinidae

    Directory of Open Access Journals (Sweden)

    Roland Farkas

    2015-04-01

    Full Text Available Chondrina tatrica Ložek, 1948 is reported for the first time for Romania. The species was thought to be endemic to the Western Carpathian Mountains. The Romanian locality (Boga valley, Bihor County is situated approximately 260 km from the nearest known site of the species in a straight line. The zoogeographical significance of this finding and the possible route of the ancestors of C. tatrica to the Carpathians is discussed.

  2. Annotated type catalogue of the Amphibulimidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London.

    Science.gov (United States)

    Breure, Abraham S H; Ablett, Jonathan D

    2011-01-01

    The type status is described of 39 taxa classified within the family Amphibulimidae (superfamily Orthalicoidea) and kept in the London museum. One taxon, Bulimus elaeodes Pfeiffer, 1853, is removed to the Strophocheilidae. Lectotypes are designated for Bulimus adoptus Reeve, 1849; Bulimus (Eurytus) eros Angas, 1878; Helix onca d'Orbigny, 1835; Amphibulima pardalina Guppy, 1868. The type status of the following taxon is changed to lectotype in accordance with Art. 74.6 ICZN: Strophocheilus (Dryptus) jubeus Fulton, 1908.As general introduction to this and following papers on Orthalicoid types in the Natural History Museum, a brief history of the London collection is given and several examples of handwriting from different authors are presented.

  3. Diversity of Edible Mollusc (Gastropoda and Bivalvia at Selected Divison of Sarawak, Malaysia

    Directory of Open Access Journals (Sweden)

    Hadi Hamli

    2012-01-01

    Full Text Available Diversity of edible mollusc was studied at eight divisions of Sarawak from August 2010 to May 2011. At each division, diversity and number of species were collected from road site selling out lets and local wet markets. Total number of mollusc was comprised of 29 species namely  Solen regularies, S. lamarckii,  Pharella acutidens, Anadara granosa, Pholas orientalis, Gluconome virens, Circe scripta, Anodonta woodina, Paphia undulata, Amusium pleuronectes, Meretrix meretrix, M. lyrata, Polymesoda bengalensis, P. erosa and P. expansa  for bivalve and  Cerithidea rizophorarum, C. obtusa, Telescopium telescopium, Clithon retropictus, Nerita articulate, N. chamaeleon, N. albicilla, Ellobium aurisjuda, Trochus radiates, Planaxis sulcatus, Monodonta labio, Turbo crasus, Thais aculate  and Melo melo  for gastropod. The species number of bivalve was recorded highest (15 species in mollusc group from Sarawak. Mollusc diversity was found highest (14 species in Bintulu and lowest (1 species in the division of Sarikei. From this study, there is a wide chance of research to further explore both on the possibility of commercial value and ecosystem conservation.

  4. Perotrochus caledonicus (Gastropoda: Pleurotomariidae revisited: descriptions of new species from the South-West Pacific

    Directory of Open Access Journals (Sweden)

    Patrick Anseeuw

    2015-08-01

    Full Text Available Morphological (shell and molecular examination of a large suite of specimens of pleurotomariids from around New Caledonia and the Coral Sea reveals the existence of four species in the complex of Perotrochus caledonicus: Perotrochus deforgesi Métivier, 1990 and P. pseudogranulosus sp. nov. live allopatrically on the plateaus and guyots of the Coral Sea; Perotrochus caledonicus Bouchet & Métivier, 1982 and Perotrochus wareni sp. nov. live sympatrically - but essentially not syntopically - on the slopes of New Caledonia, Norfolk Ridge and the Loyalty Ridge. All species live in the 300–500 m interval, and together form a significant component of the mollusc fauna living on hard bottoms in the SW Pacific, with individual dredge hauls containing up to 25 specimens of Perotrochus.

  5. New taxa of terrestrial molluscs from Turkey (Gastropoda, Pristilomatidae, Enidae, Hygromiidae, Helicidae

    Directory of Open Access Journals (Sweden)

    Burçin Gümüs

    2012-02-01

    Full Text Available This paper reports on results of several collecting trips of the authors in Turkey. In the course of this research, a long-lasting question was addressed. It could be proven that the nominal species Bulimus frivaldskyi L. Pfeiffer, 1847 is closely related to Meijeriella canaliculata Bank, 1985, and thus this species is shifted from the genus Ena Turton, 1831, to the genus Meijeriella Bank, 1985. Meijeriella canaliculata Bank, 1985, could be recorded from Turkey for the first time. The nomenclatural situation of the species Euchondrus septemdentatus (Roth, 1839 vs. its replacement name Euchondrus borealis (Mousson, 1874 is discussed. A new arrangement of the species formely comprised in the genus Zebrina Held, 1837 is presented, and the genera Rhabdoena Kobelt & Moellendorff, 1902, and Leucomastus A. Wagner, 1927 are re-established. The following species and subspecies new to science could be described: Vitrea gostelii sp. n. (Pristilomatidae, Turanena demirsoyi sp. n., Euchondrus paucidentatus sp. n., Rhabdoena gostelii sp. n. (all Enidae, Metafruticicola kizildagensis sp. n. (Hygromiidae, and Assyriella thospitis menkhorsti ssp. n. (Helicidae. For several other species, new distribution records are listed.

  6. Systematics of the family Plectopylidae in Vietnam with additional information on Chinese taxa (Gastropoda, Pulmonata, Stylommatophora

    Directory of Open Access Journals (Sweden)

    Barna Páll-Gergely

    2015-01-01

    Full Text Available Vietnamese species from the family Plectopylidae are revised based on the type specimens of all known taxa, more than 600 historical non-type museum lots, and almost 200 newly-collected samples. Altogether more than 7000 specimens were investigated. The revision has revealed that species diversity of the Vietnamese Plectopylidae was previously overestimated. Overall, thirteen species names (anterides Gude, 1909, bavayi Gude, 1901, congesta Gude, 1898, fallax Gude, 1909, gouldingi Gude, 1909, hirsuta Möllendorff, 1901, jovia Mabille, 1887, moellendorffi Gude, 1901, persimilis Gude, 1901, pilsbryana Gude, 1901, soror Gude, 1908, tenuis Gude, 1901, verecunda Gude, 1909 were synonymised with other species. In addition to these, Gudeodiscus hemmeni sp. n. and G. messageri raheemi ssp. n. are described from north-western Vietnam. Sixteen species and two subspecies are recognized from Vietnam. The reproductive anatomy of eight taxa is described. Based on anatomical information, Halongella gen. n. is erected to include Plectopylis schlumbergeri and P. fruhstorferi. Additionally, the genus Gudeodiscus is subdivided into two subgenera (Gudeodiscus and Veludiscus subgen. n. on the basis of the morphology of the reproductive anatomy and the radula. The Chinese G. phlyarius werneri Páll-Gergely, 2013 is moved to synonymy of G. phlyarius. A spermatophore was found in the organ situated next to the gametolytic sac in one specimen. This suggests that this organ in the Plectopylidae is a diverticulum. Statistically significant evidence is presented for the presence of calcareous hook-like granules inside the penis being associated with the absence of embryos in the uterus in four genera. This suggests that these probably play a role in mating periods before disappearing when embryos develop. Sicradiscus mansuyi is reported from China for the first time.

  7. Reversal of density dependence of juvenile Littorina littorea (Gastropoda) growth in response to periphyton nutrient status

    Science.gov (United States)

    Sommer, Ulrich

    2001-05-01

    Experimental periphyton communities were grown in aquaria receiving media of differently enriched seawater (fully enriched, without Si enrichment, without N and P enrichment) and supplied differently with medium (batch and weekly replacement). Periphyton was subject to grazing by 1-6 individuals of juvenile Littorina littorea. Periphyton biomass was higher in the replacement aquaria than in the batch aquaria and higher in the full and the -Si medium than in the -NP medium. The N:C ratio of the periphyton increased with Littorina number in the batch aquaria and was unaffected by Littorina number in the replacement aquaria. Diatoms were most dominant in the -NP treatments and rarest in the -Si treatments. Chlorophytes were dominant in the -Si and the fully enriched treatments, but also Cyanobacteria contributed significantly to periphyton biomass in those treatments under nutrient replacement. Somatic growth of Littorina was negatively correlated to Littorina density in the replacement aquaria and positively density dependent in the batch aquaria. The latter is explained by improved food quality under stronger grazing pressure.

  8. [Inheritance of the background shell color in the snails Littorina obtusata (Gastropoda, Littorinidae)].

    Science.gov (United States)

    Kozminsky, E V

    2014-10-01

    We investigated in a gastropod mollusk Littorina obtusata (L. obtusata) the inheritance of background shell coloration of the shell, which arises on the basis of three pigments: purple, orange, and yellow. We found that the hypothesis on polyallelic inheritance, as in the genus Cepaea, cannot explain the inheritance of shell color in periwinkles. We demonstrated that a separate genetic system is responsible for incorporation of each pigment into the shell. The composition of these genetic systems includes at least tw genes each in the case of the yellow and purple pigments. Our analysis shows that caution should be applied when extending the results obtained in the studies of the Cepaea genus to the other species of gastropods.

  9. [Morphobiochemical adaptations of Mediterranean Littorina punctata (Gmelin, 1790) (Mollusca, Gastropoda) to survival under supralittoral conditions].

    Science.gov (United States)

    Aliakrinskaia, I O

    2014-01-01

    Behavioral and morphobiochemical adaptations of Littorina punctata to dwelling under supralittoral condi- tions are analyzed. A quantitative estimation of the hemoglobin content in the radular tissues of the mollusk is given.

  10. Rediae of echinostomatid and heterophyid trematodes suppress phagocytosis of haemocytes in Littorina littorea (Gastropoda: Prosobranchia).

    Science.gov (United States)

    Iakovleva, Nadya V; Shaposhnikova, Tania G; Gorbushin, Alexander M

    2006-05-01

    A modulation of the phagocytic activity of hemocytes from the common periwinkle Littorina littorea by secretory-excretory products (SEP) released by trematode rediae during axenic in vitro cultivation was studied. The SEP released by the parasites Himasthla elongata (Echinostomatidae) and Cryptocotyle lingua (Heterophyidae) were found to inhibit the phagocytosis of zymozan particles by periwinkle hemocytes. The specificity of SEP effects was assessed: SEP of Himasthla militaris and Cryptocotyle concavum, two trematodes belonging to the same genera but infecting another closely related prosobranch snail Hydrobia ulvae, were also shown to be able to suppress L. littorea hemocytes phagocytic activity. However, no decrease in phagocytosis rate was observed when SEP of H. elongata and C. lingua were applied to monolayers of hemocytes from the bivalve mollusc Mytilus edulis. SEP from H. elongata was fractionated; only those fractions containing proteins of molecular weight more than 50 kDa were shown to possess inhibitory activity. Different H. elongata SEP concentrations were tested in for their ability to suppress phagocytosis by L. littorea hemocytes. Even very low SEP concentrations were shown to retain their ability to decrease phagocytosis rate, the inhibitory effect being dose-dependent. Hemocytes derived from snails naturally infected with H. elongata were also found to have lower phagocytic ability as compared to healthy individuals.

  11. [Inheritance of longitudinal shell bands in the snails Littorina obtusata and Littorina saxatilis (Gastropoda, Prosobranchia)].

    Science.gov (United States)

    Kozminskiĭ, E V

    2011-08-01

    The hypothesis of a monogenic inheritance of dark longitudinal bands on the shell in the gastropods Littorina obtusata and L. saxatilis was checked. One gene having two alleles proved to be responsible for the shell banding pattern in both of the species. The presence of bands was a dominant character in either case.

  12. [Inheritance of white spots on the shell of Littorina obtusata (Gastropoda, Prosobranchia)].

    Science.gov (United States)

    Kozminskiĭ, E V; Lezin, P A; Fokin, M V

    2010-12-01

    The hypothesis on monogenic inheritance of white spot pattern on the shell of the gastropod snail Littorina obtusata was tested. Although in most cases our results did not contradict this assumption, the hypothesis cannot explain the observed segregation in general. An alternative hypothesis was suggested, according to which the presence of spot pattern is controlled by two complementary biallelic genes.

  13. Not all spotted cats are leopards: evidence for a Hemilienardia ocellata species complex (Gastropoda: Conoidea: Raphitomidae

    Directory of Open Access Journals (Sweden)

    Alexander E. Fedosov

    2017-02-01

    Full Text Available The small conoidean Hemilienardia ocellata is one of the easily recognizable Indo-Pacific “turrids”, primarily because of its remarkable eyespot colour pattern. Morphological and molecular phylogenetic analyses revealed four species that share this “characteristic” colour pattern but demonstrate consistent differences in size and shell proportions. Three new species – Hemilienardia acinonyx sp. nov. from the Philippines, H. lynx sp. nov. from Papua New Guinea and H. pardus sp. nov. from the Society and Loyalty Islands – are described based on the results of phylogenetic analyses. Although the H. ocellata species complex clade falls in a monophyletic Hemilienardia, H. ocellata and H. acinonyx sp. nov. possess a radula with semi-enrolled or notably flattened triangular marginal teeth, a condition that diverges substantially from the standard radular morphology of Hemilienardia and other raphitomids.

  14. First record of Calma gobioophaga Calado and Urgorri, 2002 (Gastropoda: Nudibranchia in the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    J. PRKIC

    2014-07-01

    Full Text Available Specimens of the nudibranch genus Calma were observed under stones at two Croatian localities while feeding on gobiid eggs. Some ambiguous morphological features compared with the original descriptions of the known species of the genus, C. glaucoides and C. gobioophaga, hampered an easy identification. Genetic data (COI and 16S sequences confirmed the distinction between the two species of the genus Calma, and allowed to unambiguously identify the Croatian specimens as Calma gobioophaga. This is the first record of this species for the Mediterranean and extends remarkably its distribution range. Finally, the eggs fed by the Croatian specimens have been taxonomically identified by using the 12S rDNA marker as Gobius cobitis.

  15. A revision of the Neogene Conidae and Conorbidae (Gastropoda) of the Paratethys Sea.

    Science.gov (United States)

    Harzhauser, Mathias; Landau, Bernard

    2016-12-22

    The Miocene Conidae and Conorbidae of the central- and south-eastern European Paratethys Sea are revised. In total, 74 species are described of which 10 are new species and 5 are documented for the first time from Paratethyan localities. Species descriptions and delimitations are partly based on morphometric data. In addition, colour patterns are described for the first time for the majority of species. In respect to the ongoing discussion on the supraspecific treatment of extant Conidae, we strongly focus on generic allocations and provide a key for the genera as understood herein. Biogeographically, the larger part of the assemblage indicates affiliation with modern western African faunas as indicated by the occurrence of genera such as Lautoconus, Kalloconus, Monteiroconus and Pseudonoduloconus. The relationship with Indo-West Pacific faunas is comparatively low. The high alpha-diversities observed for localities in the Pannonian, Transylvanian and Vienna basins, with up to 44 species, is a marker of tropical conditions in the Paratethys Sea during middle Miocene times.        Conasprella minutissima nov. sp., Kalloconus hendricksi nov. sp., Kalloconus letkesensis nov. sp., Kalloconus pseudohungaricus nov. sp., Lautoconus kovacsi nov. sp., Lautoconus pestensis nov. sp., Lautoconus quaggaoides nov. sp., Leporiconus paratethyianus nov. sp., Plagioconus breitenbergeri nov. sp. and Plagioconus bellissimus nov. sp. are described as new species; Conilithes eichwaldi nov. nom. is proposed as new name for Conus exiguus Eichwald, 1830 [non Lamarck, 1810].

  16. A hitherto unnoticed adaptive radiation: epitoniid species (Gastropoda: Epitoniidae) associated with corals (Scleractinia)

    NARCIS (Netherlands)

    Gittenberger, A.; Gittenberger, E.

    2005-01-01

    Twenty-two epitoniid species that live associated with various hard coral species are described. Three genera, viz. Epidendrium gen. nov., Epifungium gen. nov., and Surrepifungium gen. nov., and ten species are introduced as new to science, viz. Epidendrium aureum spec. nov., E. sordidum spec. nov.,

  17. Microanatomy and ultrastructure of the excretory system of two pelagic opisthobranch species (Gastropoda: Gymnosomata and Thecosomata).

    Science.gov (United States)

    Fahrner, A; Haszprunar, G

    2000-04-01

    The microanatomy and ultrastructure of the excretory system of Pneumoderma sp. (Gymnosomata) and Creseis virgula Rang, 1828 (Thecosomata) have been investigated by means of semithin serial sections, reconstructions and transmission electron microscopy. The studies revealed a functional metanephridial system consisting of a heart with a single ventricle and auricle in a pericardial cavity and a single kidney in both species. Podocytes in the atrial wall of the pericardial epithelium are the site of ultrafiltration, whereas the flat epithelium of the kidney with numerous basal infoldings and a dense microvillous border on the luminal surface suggests modification of the ultrafiltrate. In Pneumoderma sp., additional loci of ultrafiltration with identical fine structure (meandering slits with diaphragms covered by extracellular matrix) occur in the solitary rhogocytes (pore cells). The presence of podocytes situated on the atrial wall in representatives of two higher opisthobranch taxa contradicts former ideas on the loss of the primary site of ultrafiltration in the ancestors of the Opisthobranchia.

  18. Patterns of diversity of the Rissoidae (Mollusca: Gastropoda) in the Atlantic and the Mediterranean region.

    Science.gov (United States)

    Ávila, Sérgio P; Goud, Jeroen; de Frias Martins, António M

    2012-01-01

    The geographical distribution of the Rissoidae in the Atlantic Ocean and Mediterranean Sea was compiled and is up-to-date until July 2011. All species were classified according to their mode of larval development (planktotrophic and nonplanktotrophic), and bathymetrical zonation (shallow species--those living between the intertidal and 50 m depth, and deep species--those usually living below 50 m depth). 542 species of Rissoidae are presently reported to the Atlantic Ocean and the Mediterranean Sea, belonging to 33 genera. The Mediterranean Sea is the most diverse site, followed by Canary Islands, Caribbean, Portugal, and Cape Verde. The Mediterranean and Cape Verde Islands are the sites with higher numbers of endemic species, with predominance of Alvania spp. in the first site, and of Alvania and Schwartziella at Cape Verde. In spite of the large number of rissoids at Madeira archipelago, a large number of species are shared with Canaries, Selvagens, and the Azores, thus only about 8% are endemic to the Madeira archipelago. Most of the 542-rissoid species that live in the Atlantic and in the Mediterranean are shallow species (323), 110 are considered as deep species, and 23 species are reported in both shallow and deep waters. There is a predominance of nonplanktotrophs in islands, seamounts, and at high and medium latitudes. This pattern is particularly evident in the genera Crisilla, Manzonia, Onoba, Porosalvania, Schwartziella, and Setia. Planktotrophic species are more abundant in the eastern Atlantic and in the Mediterranean Sea. The results of the analysis of the probable directions of faunal flows support the patterns found by both the Parsimony Analysis of Endemicity and the geographical distribution. Four main source areas for rissoids emerge: Mediterranean, Caribbean, Canaries/Madeira archipelagos, and the Cape Verde archipelago. We must stress the high percentage of endemics that occurs in the isolated islands of Saint Helena, Tristan da Cunha, Cape Verde archipelago and also the Azores, thus reinforcing the legislative protective actions that the local governments have implemented in these islands during the recent years.

  19. Mitochondrial genome of the endangered marine gastropod Strombus gigas Linnaeus, 1758 (Mollusca: Gastropoda).

    Science.gov (United States)

    Márquez, Edna J; Castro, Erick R; Alzate, Juan F

    2016-01-01

    The queen conch Strombus gigas is an endangered marine gastropod of significant economic importance across the Greater Caribbean region. This work reports for the first time the complete mitochondrial genome of S. gigas, obtained by FLX 454 pyrosequencing. The mtDNA genome encodes for 13 proteins, 22 tRNAs and 2 ribosomal RNAs. In addition, the coding sequences and gene synteny were similar to other previously reported mitogenomes of gastropods.

  20. The genus Alvania on the Canary islands and Madeira (Mollusca: Gastropoda), part 2 [final part

    NARCIS (Netherlands)

    Moolenbeek, R.G.; Hoenselaar, H.J.

    1998-01-01

    Five Alvania species from the Canary Islands and the Madeira Archipelago are revised. A new species to science, A. johannae is described and for three species lectotypes are designated. Altogether 13 littoral alvaniids are presently known from this area. Doubtful records are enumerated and a list of

  1. Unusual micrometric calcite-aragonite interface in the abalone shell Haliotis (Mollusca, Gastropoda).

    Science.gov (United States)

    Dauphin, Yannicke; Cuif, Jean-Pierre; Castillo-Michel, Hiram; Chevallard, Corinne; Farre, Bastien; Meibom, Anders

    2014-02-01

    Species of Haliotis (abalone) show high variety in structure and mineralogy of the shell. One of the European species (Haliotis tuberculata) in particular has an unusual shell structure in which calcite and aragonite coexist at a microscale with small patches of aragonite embedded in larger calcitic zones. A detailed examination of the boundary between calcite and aragonite using analytical microscopies shows that the organic contents of calcite and aragonite differ. Moreover, changes in the chemical composition of the two minerals seem to be gradual and define a micrometric zone of transition between the two main layers. A similar transition zone has been observed between the layers in more classical and regularly structured mollusk shells. The imbrication of microscopic patches of aragonite within a calcitic zone suggests the occurrence of very fast physiological changes in these taxa.

  2. Family matters: The first molecular phylogeny of the Onchidorididae Gray, 1827 (Mollusca, Gastropoda, Nudibranchia).

    Science.gov (United States)

    Hallas, Joshua M; Gosliner, Terrence M

    2015-07-01

    Recent investigations into the evolution of the Onchidorididae using morphological based methods have resulted in low support for relationships among genera. This study aims to determine if molecular data corroborates recent morphological interpretations of the evolution of Onchidorididae. Five genetic markers: 16S, 18S, 28S, cytochrome c oxidase 1 (COI) and histone 3 (H3), were sequenced from 32 species comprising Onchidorididae and five other families, three from Phanerobranchia and two from Cryptobranchia. Phylogenies were estimated using maximum likelihood, and Bayesian inference analyses; with both yielding similar topologies. Molecular analyses resulted in high support for the monophyly of the suctorian clade and the placement of the genera within Onchidorididae. However, the Onchidorididae forms a paraphyletic grouping due to the recovery of the Goniodorididae and the Akiodorididae nested within family. In addition, the placement of Corambe as the most derived member of Onchidorididae is contradicted by the present study. Rather it is sister to a large clade that includes Acanthodoris and the species traditionally placed in Onchidoris and Adalaria, now defined as Onchidorididae. We have chosen to maintain Corambidae as a distinct taxon (including Corambe and Loy), sister to Onchidorididae. We also maintain Goniodorididae, Akiodorididae and Calycidoridae (including Calycidoris and Diaphorodoris), which along with the Onchidorididae and Corambidae comprise the suctorian superfamily Onchidoridoidea. Ancestral character reconstruction also suggests that the formation of a gill pocket, a character that currently defines the Cryptobranchia, may have evolved multiple times from an ancestor that lacked the ability to retract its gills into a fully formed gill pocket. The diversity of gill morphology displayed by the Onchidoridoidea will help give new insight into the evolution of this complex character within the Nudibranchia.

  3. Estudo morfométrico da concha de Lymnaea columella say, 1817 (Mollusca, Gastropoda, Pulmonata

    Directory of Open Access Journals (Sweden)

    Marlene T. Ueta

    1980-12-01

    Full Text Available Foram estudadas variações morfométricas de conchas de L. columella, provenientes de dez criadouros localizados nos seguintes municípios do Estado de São Paulo: - Campinas, Americana, Atibaia, Pirassununga, Caçapava e Taubaté. Foram analisados os diferentes tipos de ambientes onde as limneas são encontradas com maior freqüência, estabelecendo-se a época do ano com maior abundância em espécimes, que correspondeu aos meses de julho a outubro. As medidas nas conhas dos diferentes criadouros referiram-se ao comprimento e largura da concha, comprimento e largura da abertura, comprimento da espira e número de voltas. Foram estabelecidos os coeficientes de correlação e de regressão e realizadas análises de variância entre as medidas tomadas e os índices obtidos da relação entre largura/comprimento da concha. Estas conchas foram comparadas com as de L. columella, L. viator, L. cubensis da coleção do Museu Nacional do Rio de Janeiro. Para a maioria das medidas as conchas mostraram proporções constantes, embora apresentassem diferenças em relação ao desenvolvimento. A maior variação foi observada em relação ao comprimento da espira. As variações morfométricas das conchas foram relacionadas com alguns fatores externos como pH, alcalinidade, dureza e teor da água. Aparentemente apenas a dureza total da água influiu na consistência das conchas.

  4. Integrative taxonomy of the genus Onchidium Buchannan, 1800 (Mollusca, Gastropoda, Pulmonata, Onchidiidae)

    Science.gov (United States)

    Dayrat, Benoît; Goulding, Tricia C.; Apte, Deepak; Bhave, Vishal; Joseph Comendador; Qua,ng, Ngô Xuân; Tan, Siong Kiat; Tan, Shau Hwai

    2016-01-01

    Abstract In an effort to clarify the species diversity of onchidiid slugs, the taxonomy of the genus Onchidium Buchannan, 1800 is revised using an integrative approach. New, fresh specimens were collected in a large number of places, including type localities. The genus Onchidium is redefined here as a clade including only three species which are strongly supported by both morphological and molecular data. All three species were already named: the type species Onchidium typhae Buchannan, 1800, Onchidium stuxbergi (Westerlund, 1883), and Onchidium reevesii (J.E. Gray, 1850). With the exception of a re-description of Onchidium typhae published in 1869, all three species are re-described here for the first time. First-hand observations on the color variation of live animals in their natural habitat are provided. The anatomy of each species is described. Important nomenclatural issues are addressed. In particular, Labella Starobogatov, 1976 is regarded as a junior synonym of Onchidium and Labella ajuthiae (Labbé, 1935) and Onchidium nigrum (Plate, 1893) are regarded as junior synonyms of Onchidium stuxbergi. The nomenclatural status of several other species names is discussed as well. Many new records are provided across South-East Asia and precise ranges of geographic distributions are provided for the genus Onchidium and its three species. Distinctive features that help distinguish the genus Onchidium from other onchidiids are provided, as well as an identification key for the three species. PMID:27917062

  5. Gastropoda(Mollusca) of Huaibei Region%淮北市的螺类

    Institute of Scientific and Technical Information of China (English)

    邓道贵; 金宏; 陈海峰

    2002-01-01

    报道了淮北市螺类共17种,其中淡水螺类15种,陆生螺类2种,分别隶属于腹足纲的6科、10属,有3种为安徽省首次记录.作者还阐述了17种螺类的生态分布、区域分布及优势种等情况.并根据淮北市的特点,对它们的开发与利用进行了初步探讨.

  6. Unraveling the evolutionary history of the Chilostoma Fitzinger, 1833 (Mollusca, Gastropoda, Pulmonata) lineages in Greece.

    Science.gov (United States)

    Psonis, Nikolaos; Vardinoyannis, Katerina; Mylonas, Moisis; Poulakakis, Nikos

    2015-10-01

    The land snails of the genus Chilostoma Fitzinger, 1833 that includes, in Greece, the (sub)genera Cattania, Josephinella and Thiessea, are highly diversified and present high levels of endemism. However, their evolutionary history is unknown and their taxonomy is complex and continuously revised. The aim of this study is to investigate the phylogenetic relationships of the lineages of the genus Chilostoma distributed in Greece based on partial DNA sequences of two mitochondrial DNA (16S rRNA and COI) genes. Complete sequences of one nuclear gene (ITS1) representing the major mitochondrial lineages were also analyzed. The phylogenetic trees revealed three distinct major clades that correspond to the three (sub)genera. Several taxonomical incongruencies were made obvious, thus, raising questions about the "true" number of species in each clade, while rendering a taxonomic re-evaluation necessary. From a phylogeographic point of view, it seems that the three major phylogenetic clades were separated in the late Miocene. They started differentiating into distinct species during the Pliocene and Pleistocene through several vicariance and dispersal events.

  7. A new Taheitia species (Mollusca: Gastropoda Prosobranchia: Truncatellidae) from Irian Jaya

    NARCIS (Netherlands)

    Gittenberger, E.

    1989-01-01

    Shells and an operculum of Taheitia heinrichi spec. nov. are described from the Vogelkop area in western Irian Jaya. This new species, dedicated to the late Heinrich C. Kavelaars, is somewhat similar to T. orrae, known from the island of Biak.

  8. Deroceras saronicum spec. nov., eine neue Nacktschneckenart aus Griechenland (Mollusca: Gastropoda: Pulmonata: Agriolimacidae)

    NARCIS (Netherlands)

    Rähle, W.

    1986-01-01

    Deroceras saronicum spec. nov., probably belonging to the subgenus Deroceras s.str., is described. The species is known from the islands of Aegina and Moni (Saronic Gulf) and from the adjacent NE. Peloponnesus, Greece. It is compared with Deroceras maltzani (SIMROTH), a similar species from southern

  9. Dating and biogeographical patterns in the sea slug genus Acanthodoris Gray, 1850 (Mollusca, Gastropoda, Nudibranchia).

    Science.gov (United States)

    Hallas, Joshua M; Simison, W Brian; Gosliner, Terrence M

    2016-04-01

    Recent studies investigating vicariance and dispersal have been focused on correlating major geological events with instances of taxonomic expansion by incorporating the fossil record with molecular clock analyses. However, this approach becomes problematic for soft-bodied organisms that are poorly represented in the fossil record. Here, we estimate the phylogenetic relationships of the nudibranch genus Acanthodoris Gray, 1850 using three molecular markers (16S, COI, H3), and then test two alternative geologically calibrated molecular clock scenarios in BEAST and their effect on ancestral area reconstruction (AAR) estimates employed in LAGRANGE. The global temperate distribution of Acanthodoris spans multiple geological barriers, including the Bering Strait (∼5.32 Mya) and the Baja Peninsula (∼5.5 Mya), both of which are used in our dating estimates. The expansion of the Atlantic Ocean (∼95-105 Mya) is also used to calibrate the relationship between A. falklandica Eliot, 1905 and A. planca Fahey and Valdés, 2005, which are distributed in southern Chile and South Africa respectively. Phylogenetic analyses recovered strong biogeographical signal and recovered two major clades representing northern and southern hemispheric distributions of Acanthodoris. When all three geological events are applied to the calibration analyses, the age for Acanthodoris is estimated to be mid-Cretaceous. When the expansion of the Atlantic Ocean is excluded from our analyses, however, Acanthodoris is estimated to be much younger, with a divergence time estimate during the Miocene. Regardless of divergence estimates, our AAR suggests that Acanthodoris may have origins in the Atlantic Ocean with the Atlantic acting as a dispersal point to the northeastern Pacific. These results suggest that Acanthodoris exhibits a rare instance of western trans-arctic expansion. This study also shows that northeast Pacific specimens of A. pilosa should be regarded as A. atrogriseata and that A. serpentinotus should be regarded as a synonym of A. pina.

  10. A new Middle Miocene Niveria Jousseaume, 1884 (Mollusca: Gastropoda: Trivioidea) from Hungary

    Science.gov (United States)

    Fehse, Dirk

    2011-02-01

    A new species of Niveria from the Middle Miocene (Badenian) of the Paratethys of Borsodbóta, Hungary is described. This species is characterized by its callused dorsum and dorsal depression. Niveria jozefgregoi sp. nov. is discussed with comparative species from the Badenian of Hungary, the Pliocene of the Mediterranean region, Florida and Recent species from Madeira and the Islas Galápagos.

  11. A Pyrenean Monacha species Monacha (Metatheba) Atacis spec. nov. (Mollusca: Gastropoda: Pulmonata)

    NARCIS (Netherlands)

    Gittenberger, E.; Winter, de A.J.

    1985-01-01

    Monacha (Metatheba) atacis spec. nov. is described from the French NE Pyrenees. The status of Metatheba, hitherto known from Caucasia and Asia Minor only, as well as that of other Monacha "subgenera" is discussed.

  12. Rich and rare—First insights into species diversity and abundance of Antarctic abyssal Gastropoda (Mollusca)

    Science.gov (United States)

    Schwabe, Enrico; Michael Bohn, Jens; Engl, Winfried; Linse, Katrin; Schrödl, Michael

    2007-08-01

    The abyssal depths of the polar oceans are thought to be low in diversity compared with the shallower polar shelves and temperate and tropical deep-sea basins. Our recent study on the gastropod fauna of the deep Southern Ocean gives evidence of the existence of a rich gastropod assemblage at abyssal depths. During the ANDEEP I and II expeditions to the southern Drake Passage, Northwestern Weddell Sea, and South Sandwich Trench, gastropods were collected by bottom and Agassiz trawls, epibenthic sledge, and multicorer, at 40 stations in depths between 127 and 5194 m. On the whole, 473 specimens, corresponding to 93 species of 36 families, were obtained. Of those, 414 specimens were caught below 750 m depth and refer to 84 (90%) benthic species of 32 (89%) families. Most families were represented by a single species only. The numerically dominant families were Skeneidae and Buccinidae (with 10 and 11 species, respectively), Eulimidae and Trochidae (with 9 species each), and Turridae (6 species). Thirty-Seven benthic deep-sea species (44%) were represented by a single specimen, and another 20 species (24%) were found at a single station, suggesting that more than two thirds of Antarctic deep-sea gastropod species are very rare or have a very scattered distribution. Of the 27 species occurring at two or more deep-sea stations, 14 were collected with different gear. Approximately half of the deep-water species are new to science or have been recently described. The present investigation increases the total number of recorded benthic Antarctic deep-sea gastropods (below 750 m) from 115 to 177. The previously known depth ranges have been extended, often considerably, for 31 species. The collected deep-sea gastropods comprise both eurybathic shelf species (29%) and apparently true deep-sea species (58%); some of the latter may belong to a so far unknown Antarctic abyssal fauna. Geographical ranges of the collected Antarctic benthic deep-sea gastropod species appear limited, and all these 84 species seem endemic to Antarctica south of the Polar Front. Comparing diversity and abundances based on epibenthic sledge samples, there is no clear relationship between Antarctic deep-sea gastropod abundance and species richness with depth. However, both Antarctic and adjacent deep-sea areas are still far from being adequately sampled to allow more comprehensive conclusions.

  13. The first record of Anisus vorticulus (Troschel, 1834 (Gastropoda: Planorbidae in Croatia?

    Directory of Open Access Journals (Sweden)

    Luboš Beran

    2009-12-01

    Full Text Available A threatened planorbid gastropod Anisus vorticulus (Troschel, 1834, listed in the EU Habitat Directive, was found in the Krka National Park in Croatia in August 2009. This find is the first known record at least in the western part of Croatia belonging to the Adriatic Sea drainage area.

  14. Prestonellinae-validation of the name as a new subfamily of Bothriembryontidae (Mollusca, Gastropoda, Orthalicoidea).

    Science.gov (United States)

    Bruggen, A C Van; Herbert, David G; Breure, Abraham S H

    2016-02-29

    The affinities of the enigmatic South African land snail genus Prestonella Connolly, 1929 were discussed by Herbert (2007) and Herbert & Mitchell (2009), who showed, on the basis of morphological and molecular data, that the genus is referable to the superfamily Orthalicoidea. Currently, the three described species of Prestonella are the only known African representatives of this diverse superfamily. Earlier, van Bruggen (1978) had recognized that these species formed a distinct group and had placed them in the (new) family Prestonellidae. However, as noted by Bouchet & Rocroi (2005: 140), no diagnosis was provided by van Bruggen; the name Prestonellidae thus does not meet the requirements of ICZN Art. 13.1, and is not an available name. In this paper we will redress this issue, also taking into account more recent research which has shed light on the systematic position of this genus within the Orthalicoidea.

  15. Holoplanktonic mollusks (Mollusca: Gastropoda) from the Gulf of California, México

    OpenAIRE

    Angulo Campillo, Orso; Aceves Medina, Gerardo; Avendaño Ibarra, Raymundo

    2011-01-01

    We compiled a checklist of holoplanktonic mollusks obtained from seven oceanographic surveys performed between 2005 and 2007 in the Gulf of California, Mexico. The checklist comprises five orders,15 families, 28 genera and 62 species, including 39 new records and two range extensions within the Gulf.

  16. Severnsia strombeulima n. gen. & sp. from Hawaii (Mollusca, Gastropoda: Caenogastropoda: Eulimidae).

    Science.gov (United States)

    Geiger, Daniel L

    2016-02-29

    The malacofauna of Hawaii is rather well-known, owing to Kay (1979) and Severns (2011). Both works stand out because they include a large number of the generally under-represented micromollusks (<5 mm). Here a striking new genus and species of a microsnail is reported from that region.

  17. Caracterização da microbiota bacteriana de Biomphalaria glabrata (Say, 1818)(Mollusca: Gastropoda)

    OpenAIRE

    Silva, Tatiana Maria da

    2012-01-01

    Devido a grande importância da microbiota no desenvolvimento de parasitas nos invertebrados, muitos estudos vêm sendo desenvolvidos para o melhor entendimento desta interação. Desta forma, a associação entre microrganismos e seus hospedeiros invertebrados, vetores de doenças, está se tornando cada vez mais evidente. Com base nisto, o objetivo do presente estudo foi caracterizar a microbiota bacteriana de caramujos da espécie Biomphalaria glabrata, principal hospedeiro interm...

  18. ESR dating of Soma (Manisa, West Anatolia - Turkey) fossil gastropoda shells

    Energy Technology Data Exchange (ETDEWEB)

    Engin, Birol [Ankara Nuclear Research and Training Center, 06100 Besevler, Ankara (Turkey)]. E-mail: birol_engin65@yahoo.com; Kapan-Yesilyurt, Sevinc [Canakkale Onsekiz Mart University, Department of Geological Engineering, Canakkale (Turkey); Taner, Gueler [Ankara University, Department of Geological Engineering, Tandogan, Ankara (Turkey); Demirtas, Hayruennisa [Ankara Nuclear Research and Training Center, 06100 Besevler, Ankara (Turkey); Eken, Mahmut [Ankara Nuclear Research and Training Center, 06100 Besevler, Ankara (Turkey)

    2006-02-15

    Electron spin resonance (ESR) spectroscopy technique has been employed to date the aragonitic fresh-water gastropod shells (Melanoides curvicosta) collected from Soma (Manisa) district (West Anatolia) of Turkey. The influence of the annealing temperature and {gamma}-radiation dose on dating signal at g = 2.0016 is investigated. The thermal stability and dose response of the ESR signals were found to be suitable for an age determination using a signal at g = 2.0016. The activation energy (E), frequency factor (s) and mean-lifetime ({tau}) at 15 deg. C of the g = 2.0016 center were calculated to be 1.67 {+-} 0.01 eV (3.6 {+-} 0.7) x 10{sup 13} s{sup -1} and 2.02 x 10{sup 8} years, respectively. The ESR signal growth curve on additional {gamma}-irradiation has been best fitted by an exponential saturation function. Based on this model, accumulated dose (AD) value for dating is obtained. We have determined the ESR age of the terrestrial gastropods to be 2.57 {+-} 0.30 Ma. The results show that the ESR age falls into the Late Pliocene (Romanian) epoch of the geological time scale, which agreed with the paleoecological and paleogeographic distribution and stratigraphic level of the fauna.

  19. Odontomariinae, a new middle paleozoic subfamily of slit-bearing euophaloidean gastropods (Euophalomorpha, Gastropoda)

    Science.gov (United States)

    Fryda, J.; Heidelberger, D.; Blodgett, R.B.

    2006-01-01

    A new subfamily, the Odontomariinae subfam. nov., is established herein for a distinctive group of uncoiled, slit-bearing Middle Devonian euomphalid gastropods. Its taxonomic position is based on the recent discovery of open coiled protoconchs and it is placed within the Euomphalomorpha. The genera Odontomaria Odontomaria C. F. Roemer and Tubiconcha n. gen. belonging to this new subfamily are enlarged based on studies on new material of the following species: Odontomaria semiplicata (Sandberger & Sandberger), Odontomaria gracilis n. sp., Odontomaria jankei n. sp., Odontomaria cheeneetnukensis n. sp., Odontomaria cindiprellerae n. sp. and Tubiconcha leunissi (Heidelberger, 2001). Members of the Odontomariinae were mainly sedentary organisms in high-energy, moderately shallow water. ?? 2006 E. Schweizerbart'sche Verlagsbuchhandlung.

  20. [Expression of genes encoding defense factors in the snail Planorbarius corneus (Gastropoda, Pulmonata) infested with trematodes].

    Science.gov (United States)

    Prokhorova, E E; Tsymbalenko, N V; Ataev, G L

    2010-01-01

    Because many species of gastropods are intermediate hosts for trematodes, these molluscs are often used as model-organisms in the studies of invertebrate immune system. Revealing of the ways in which the defense factors functioning became possible due to the use of the methods of molecular biology. Contemporary molecular methods allow analyzing the defense factors allocations and levels of their expression. We investigated the expression of genes encoding defense factors in gastropods by the example of the snail Planorbarius corneus from water bodies of the Leningrad Oblast under infestation with trematods. The snails naturally infested with the parthenites of trematode species belonging to the families Strigeidae, Notocotylidae, Plagiorchiidae, and Schistosomatida were used as the experimental sample. Uninfested snails were used as a control sample. Several genes encoding the factors, which have been recently found involved in the anti-trematode defense reactions in pulmonates, were chosen, namely fibrinogen-related protein, C-lectin, calcium-binding protein, and cystatin-like protein. The genes' expression was analyzed on total mRNA samples by the reverse transcription with the polymerase chain reaction. It was shown than expression levels of the genes under consideration are different in uninfested snails and in the snails infested with different trematode species. Thus, in the mollusks infested with the parthenites of Cotylurus sp. and Bilharziella polonica, the expression levels of the genes of all factors under study were increased, while in the infested Notocotylus sp. n Plagiorchis sp., only expression levels of C-lectin and cystatin-like protein were increased. Results of the expression analysis confirm the role of hemocytes and cells of hepatopancreas in the production of humoral defense factors. In the snails infested with trematodes, the expression levels of C-lectin and calcium-binding protein genes are increased in haemocytes, while the genes of fibrinogen-related and cystatin-like proteins are activated in the hepatopancreas. Our data also confirm the role of the factors examined in the anti-trematode defense reactions in pulmonates.

  1. Molecular phylogeny of the Ellobiidae (Gastropoda: Panpulmonata) supports independent terrestrial invasions.

    Science.gov (United States)

    Romero, Pedro E; Pfenninger, Markus; Kano, Yasunori; Klussmann-Kolb, Annette

    2016-04-01

    Gastropods of the family Ellobiidae are an interesting group in which to study transitions from intertidal to terrestrial realms. However, the phylogenetic relationships within this family still lack resolution. We present a phylogenetic hypothesis of the Ellobiidae based on Bayesian and maximum likelihood phylograms. We used nuclear (18S, 28S, H3) and mitochondrial (16S, 12S, COI) data, increasing the numbers of markers and data, and making this the most comprehensive phylogenetic study of the family to date. Our results support phylogenetic hypotheses derived from morphological data, and provide a supported framework to evaluate the internal relationships within Ellobiidae. The resulting phylogenetic trees support the previous hypothesis that the Ellobiidae are monophyletic only if the Trimusculinae (Otina, Smeagol and Trimusculus) are considered part of this family. In addition, we found that the Carychiinae, Ellobiinae and Pythiinae are reciprocally monophyletic and closely related, with the Carychiinae as sister group to Ellobiinae. Relationships within Melampodinae and Pedipedinae and their phylogenetic positions remain unresolved. Land invasion by the Ellobiidae occurred independently in Carychiinae and Pythia during different geological times (Mesozoic and Cenozoic, respectively). Diversification in the family does not appear to be related to past climate and biotic changes, neither the Cretaceous-Paleogene boundary nor the lowering of the sea level in the Oligocene.

  2. Two problematic, troglophilous gastropods from the Peloponnese, Greece (Gastropoda: Pulmonata: Zonitidae)

    NARCIS (Netherlands)

    Gittenberger, E.

    2008-01-01

    Two species of pulmonate gastropods are described as new to science although their generic classification remains uncertain since only shells are available for study. The species might be troglodytes. Their shells indicate the presence of subterraneous material.

  3. Terrestrial gastropods of Srebarna Nature Reserve, North-Eastern Bulgaria (Gastropoda

    Directory of Open Access Journals (Sweden)

    Ivailo Dedov

    2015-01-01

    Full Text Available We give the results from the first investigation focused on the land snail fauna in Srebarna Nature Reserve in Bulgaria. A total of 23 localities were studied and 27 species of terrestrial gastropods were found, 23 of which were new observations for the Reserve.

  4. Transcriptome analysis in Concholepas concholepas (Gastropoda, Muricidae): mining and characterization of new genomic and molecular markers.

    Science.gov (United States)

    Cárdenas, Leyla; Sánchez, Roland; Gomez, Daniela; Fuenzalida, Gonzalo; Gallardo-Escárate, Cristián; Tanguy, Arnaud

    2011-09-01

    The marine gastropod Concholepas concholepas, locally known as the "loco", is the main target species of the benthonic Chilean fisheries. Genetic and genomic tools are necessary to study the genome of this species in order to understand the molecular basis of its development, growth, and other key traits to improve the management strategies and to identify local adaptation to prevent loss of biodiversity. Here, we use pyrosequencing technologies to generate the first transcriptomic database from adult specimens of the loco. After trimming, a total of 140,756 Expressed Sequence Tag sequences were achieved. Clustering and assembly analysis identified 19,219 contigs and 105,435 singleton sequences. BlastN analysis showed a significant identity with Expressed Sequence Tags of different gastropod species available in public databases. Similarly, BlastX results showed that only 895 out of the total 124,654 had significant hits and may represent novel genes for marine gastropods. From this database, simple sequence repeat motifs were also identified and a total of 38 primer pairs were designed and tested to assess their potential as informative markers and to investigate their cross-species amplification in different related gastropod species. This dataset represents the first publicly available 454 data for a marine gastropod endemic to the southeastern Pacific coast, providing a valuable transcriptomic resource for future efforts of gene discovery and development of functional markers in other marine gastropods.

  5. Terrestrial gastropods of Srebarna Nature Reserve, North-Eastern Bulgaria (Gastropoda).

    Science.gov (United States)

    Dedov, Ivailo; Antonova, Vera

    2015-01-01

    We give the results from the first investigation focused on the land snail fauna in Srebarna Nature Reserve in Bulgaria. A total of 23 localities were studied and 27 species of terrestrial gastropods were found, 23 of which were new observations for the Reserve.

  6. Contribution to the knowledge of the terrestrial gastropods (Mollusca:Gastropoda from Vrachanska Planina Mountains

    Directory of Open Access Journals (Sweden)

    IVAILO K. DEDOV

    2016-05-01

    Full Text Available Gastropods fauna from the Vrachanska Planina Mountains (= Vrachanska Planina, Northwest Bulgaria, as well it presents the up to now unpublished results of several research trips of the authors and further collectors in the region. In total 90 terrestrial gastropods species are now known from this mountain area. 78 species were published from the beginning of research in this area up to recently. 56 species were confirmed with new findings and 22 species were not found again while the courses of our investigations. 12 gastropod species are newly recorded for the range.

  7. The phylogenetic position of Neritimorpha based on the mitochondrial genome of Nerita melanotragus (Mollusca: Gastropoda).

    Science.gov (United States)

    Castro, Lyda R; Colgan, D J

    2010-11-01

    This is the first report of the mitochondrial gene order and almost-complete DNA sequence of a representative of the Neritimorpha, the highest-ranking gastropod clade lacking such data. Mitochondrial gene order in Nerita is largely plesiomorphic. Its only difference from the cephalopod Octopus vulgaris is a tRNA transposition shared by Vetigastropoda and Caenogastropoda. Genome arrangements were not informative enough to resolve the evolutionary relationships of Neritimorpha, Vetigastropoda and Caenogastropoda. The sister-group taxon of Neritimorpha varied in sequence-based analyses. Some suggested that Neritimorpha is the sister group of Caenogastropoda plus Heterobranchia and some that Neritimorpha and Caenogastropoda are sister groups. No analysis significantly supported the hypothesis that Vetigastroda is more closely related to Caenogastropoda than is Neritimorpha.

  8. Mitochondrial DNA hyperdiversity and its potential causes in the marine periwinkle Melarhaphe neritoides (Mollusca: Gastropoda)

    OpenAIRE

    2016-01-01

    We report the presence of mitochondrial DNA (mtDNA) hyperdiversity in the marine periwinkle Melarhaphe neritoides (Linnaeus, 1758), the first such case among marine gastropods. Our dataset consisted of concatenated 16S-COI-Cytb gene fragments. We used Bayesian analyses to investigate three putative causes underlying genetic variation, and estimated the mtDNA mutation rate, possible signatures of selection and the effective population size of the species in the Azores archipelago. The mtDNA hy...

  9. Atlanta ariejansseni, a new species of shelled heteropod from the Southern Subtropical Convergence Zone (Gastropoda, Pterotracheoidea).

    Science.gov (United States)

    Wall-Palmer, Deborah; Burridge, Alice K; Peijnenburg, Katja T C A

    2016-01-01

    The Atlantidae (shelled heteropods) is a family of microscopic aragonite shelled holoplanktonic gastropods with a wide biogeographical distribution in tropical, sub-tropical and temperate waters. The aragonite shell and surface ocean habitat of the atlantids makes them particularly susceptible to ocean acidification and ocean warming, and atlantids are likely to be useful indicators of these changes. However, we still lack fundamental information on their taxonomy and biogeography, which is essential for monitoring the effects of a changing ocean. Integrated morphological and molecular approaches to taxonomy have been employed to improve the assessment of species boundaries, which give a more accurate picture of species distributions. Here a new species of atlantid heteropod is described based on shell morphology, DNA barcoding of the Cytochrome Oxidase I gene, and biogeography. All specimens of Atlanta ariejansseni sp. n. were collected from the Southern Subtropical Convergence Zone of the Atlantic and Indo-Pacific oceans suggesting that this species has a very narrow latitudinal distribution (37-48°S). Atlanta ariejansseni sp. n. was found to be relatively abundant (up to 2.3 specimens per 1000 m(3) water) within this narrow latitudinal range, implying that this species has adapted to the specific conditions of the Southern Subtropical Convergence Zone and has a high tolerance to the varying ocean parameters in this region.

  10. Recent history of the European Nassarius nitidus (Gastropoda) : phylogeographic evidence of glacial refugia and colonization pathways

    NARCIS (Netherlands)

    Albaina, Naiara; Olsen, Jeanine L.; Couceiro, Lucia; Miguel Ruiz, Jose; Barreiro, Rodolfo

    2012-01-01

    Because marine species respond differentially to factors governing survival and gene flow, closely related taxa may display dissimilar phylogeographic histories. New data for the patchily distributed gastropod Nassarius nitidus throughout its Atlantic-Mediterranean range (collected during 2008 and 2

  11. Systematics and Distribution of Siphocypraea mus and Propustularia surinamensis (Gastropoda, Cypraeidae)

    NARCIS (Netherlands)

    Coomans, H.E.

    1963-01-01

    The systematic place of “Cypraea” mus Linné is discussed, and it is concluded that the species belongs in Siphocypraea (Akleistostoma). The “varieties” tuberculata Gray and bicornis Sowerby should be withdrawn; they are only forms with callosities. Callus formations are often found in Cypraeidae. Th

  12. A new Deroceras species from North_Western spain (Gastropoda: Pulmonata: Agriolimacidae)

    NARCIS (Netherlands)

    Winter, de A.J.

    1985-01-01

    Deroceras ercinae spec. nov. is described from the Cantabrian Mountains, Spain. The characters used to define the subgenera of Deroceras are discussed. It is demonstrated that the present subdivision of this genus into subgenera is not based on synapomorphic characters.

  13. Biochemical and Ultrastructural Changes in the Hepatopancreas of Bellamya aeruginosa (Gastropoda Fed with Toxic Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Jinyong Zhu

    2011-01-01

    Full Text Available This study was conducted to investigate ultrastructural alterations and biochemical responses in the hepatopancreas of the freshwater snail Bellamya aeruginosa after exposure to two treatments: toxic cyanobacterium (Microcystis aeruginosa and toxic cyanobacterial cells mixed with a non-toxic green alga (Scendesmus quadricauda for a period of 15 days of intoxication, followed by a 15-day detoxification period. The toxic algal suspension induced a very pronounced increase of the activities of acid phosphatases, alkaline phosphatases and glutathione S-transferases (ACP, ALP and GST in the liver at the later stage of intoxication. During the depuration, enzymatic activity tended to return to the levels close to those in the control. The activity of GST displayed the most pronounced response among different algal suspensions. Severe cytoplasmic vacuolization, condensation and deformation of nucleus, dilation and myeloid-like in mitochondria, disruption of rough endoplasmic reticulum, proliferation of lysosome, telolysosomes and apoptotic body were observed in the tissues. All cellular organelles began recovery after the snails were transferred to the S. quadricauda. The occurrence of a large amount of activated lysosomes and heterolysosomes and augment in activity of detoxification enzyme GST might be an adaptive mechanism to eliminate or lessen cell damage caused by hepatotoxicity to B. aeruginosa.

  14. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus).

    Science.gov (United States)

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants.

  15. Notes on Rivomarginella electrum (Reeve, 1865) from Lampung, South Sumatra (Gastropoda, Marginellidae)

    NARCIS (Netherlands)

    Djajasasmita, Machfudz; Coomans, Henry E.

    1980-01-01

    Specimens of the freshwater marginellid Rivomarginella electrum (Reeve) were collected in South Sumatra. The erroneous spelling of the type locality is corrected into Lake Jepara. The animal, radula and ecology are described for the first time; living specimens were observed in an aquarium. The spec

  16. A comparative ultrastructural investigation of the cephalic sensory organs in Opisthobranchia (Mollusca, Gastropoda).

    Science.gov (United States)

    Göbbeler, K; Klussmann-Kolb, A

    2007-12-01

    Cephalic sensory organs (CSOs) are specialised structures in the head region of adult Opisthobranchia involved in perception of different stimuli. The gross morphology of these organs differs considerably among taxa. The current study aims at describing the cellular morphology of the CSOs in order to reveal cellular patterns, especially of sensory epithelia, common for opisthobranchs. Transmission electron microscopy was used to characterise the fine structure of the organs and to compare the CSOs of four different opisthobranch species. The cellular composition of the sensory system is conserved among taxa. The epidermal cells in sensory regions are always columnar and ciliated cells are frequently apparent. The sensory cells are primary receptors arranged in subepidermal cell clusters. They extend dendrites which penetrate the epithelium and reach the surface. Some of the dendrites bear cilia, whereas others only build a small protuberance. Processing of sensory information takes place in the peripheral glomeruli of all species. Moreover, few taxa possess additional peripheral ganglia at the base of their CSOs. The results of the present study might support other investigations indicating that the posterior CSOs are primarily involved in distance chemoreception, whereas the anterior CSOs might be used for contact chemoreception and mechanoreception.

  17. Land snails (Mollusca: Gastropoda of India: status, threats and conservation strategies

    Directory of Open Access Journals (Sweden)

    S. Sen

    2012-09-01

    Full Text Available Land snails form an important component in the forest ecosystem. In terms of number of species, the phylum Mollusca, to which land snails belong, is the largest phylum after Arthropoda. Mollusca provide unique ecosystem services including recycling of nutrients and they provide a prey base for small mammals, birds, snakes and other reptiles. However, land snails have the largest number of documented extinctions, compared to any other taxa. Till date 1,129 species of land snails are recorded from Indian territory. But only basic information is known about their taxonomy and little is known of their population biology, ecology and their conservation status. In this paper, we briefly review status, threats and conservation strategies of land snails of India.

  18. Four marine digenean parasites of Austrolittorina spp. (Gastropoda: Littorinidae) in New Zealand: morphological and molecular data.

    Science.gov (United States)

    O'Dwyer, Katie; Blasco-Costa, Isabel; Poulin, Robert; Faltýnková, Anna

    2014-10-01

    Littorinid snails are one particular group of gastropods identified as important intermediate hosts for a wide range of digenean parasite species, at least throughout the Northern Hemisphere. However nothing is known of trematode species infecting these snails in the Southern Hemisphere. This study is the first attempt at cataloguing the digenean parasites infecting littorinids in New Zealand. Examination of over 5,000 individuals of two species of the genus Austrolittorina Rosewater, A. cincta Quoy & Gaimard and A. antipodum Philippi, from intertidal rocky shores, revealed infections with four digenean species representative of a diverse range of families: Philophthalmidae Looss, 1899, Notocotylidae Lühe, 1909, Renicolidae Dollfus, 1939 and Microphallidae Ward, 1901. This paper provides detailed morphological descriptions of the cercariae and intramolluscan stages of these parasites. Furthermore, partial sequences of the 28S rRNA gene and the mitochondrial gene cytochrome c oxidase subunit 1 (cox1) for varying numbers of isolates of each species were obtained. Phylogenetic analyses were carried out at the superfamily level and along with the morphological data were used to infer the generic affiliation of the species.

  19. A nomenclator of extant and fossil taxa of the Melanopsidae (Gastropoda, Cerithioidea).

    Science.gov (United States)

    Neubauer, Thomas A

    2016-01-01

    This nomenclator provides details on all published names in the family-, genus-, and species-group, as well as for a few infrasubspecific names introduced for, or attributed to, the family Melanopsidae. It includes nomenclaturally valid names, as well as junior homonyms, junior objective synonyms, nomina nuda, common incorrect subsequent spellings, and as far as possible discussion on the current status in taxonomy. The catalogue encompasses three family-group names, 79 genus-group names, and 1381 species-group names. All of them are given in their original combination and spelling (except mandatory corrections requested by the Code), along with their original source. For each family- and genus-group name, the original classification and the type genus and type species, respectively, are given. Data provided for species-group taxa are type locality, type horizon (for fossil taxa), and type specimens, as far as available.

  20. Anatomia e histologia do aparelho reprodutor masculino de Pomacea canaliculata (Lamarck, 1822 (Mollusca, Gastropoda, Pilidae

    Directory of Open Access Journals (Sweden)

    Eliana de Fátima Marques de Mesquita

    1990-01-01

    Full Text Available In this paper the authors give an anatomical and histological analysis of the male reproductive system of Pomacea canaliculata (Lamarck, 1822. Anatomically, the testis is better evidentiated than the ovary. In the structure of the testis a great number of very small channels converges to a single one. The male copulatory organs result of transformations that take place in the inner surface on the palial membrane. Histologically, the testis of immature males shows seminiferous ducts with round egg-shaped forms. In their lumens we could notice masses of cells that will originate spermatozoids. The penis has a conjunctive muscular sheath that can be seen in van Gieson's coloured preparations.

  1. Record of imposex in Cronia konkanensis (Gastropoda, Muricidae) from Indian waters

    Digital Repository Service at National Institute of Oceanography (India)

    VishwaKiran, Y.; Anil, A.C.

    -biocides into the North sea—an estimation. Deutsche Hydrographische Zeitschrite, 46, 355–364. Kelly, J. R., Rudnick, D. T., Dana-Morton, R., Buttel, L. A., Levine, S. N., & Carr, K. A. (1990). Tri- butyltin and invertebrates of a seagrass ecosystem: exposure and response...

  2. Freshwater snail Pomacea bridgesii (Gastropoda: Ampullariidae, life history traits and aquaculture potential

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    Ana R. A. Coelho

    2012-07-01

    Full Text Available Investigations on the reproductive biology, life cycle and feeding habits of Pomacea bridgesiihave been undertaken to assess its potential as a cultured species for the ornamental trade. The speciesis dioecious and, under optimal culture conditions of temperature and food supply, it can breed all yearround. The total developmental period at 23±1ºC varied from 15 to 24 days after oviposition. Hatchingcan last for up to 20 hours in the same egg cluster. Hatching success was very high (mean94.56±0.62% and no significant differences were observed in hatching rates between different clutchsizes. Development is direct and juveniles hatch at shell length (SL = 2.4±0.25 mm. Maturity is reached192±1.5 days after hatching and at SL = 32.80±2.03 mm. Two feeding experiments were undertaken toassess the impact of food type on juvenile survival during the first 8 days post-hatching and subsequentgrowth until 90 days post-hatching. Compatibility between other fish and plants fresh-water aquariumspecies were performed. A combination of environmental tolerance, moderately amphibious behavior,fast growth, short development and hatching at an advanced stage, compatibility with other aquariumspecies (fishes or other invertebrates, and simple low cost diet, make P. bridgesii highly suitable forintensive culture for the ornamental trade.

  3. Population biology of the gastropod Olivella minuta (Gastropoda, Olividae) on two sheltered beaches in southeastern Brazil

    Science.gov (United States)

    Petracco, Marcelo; Camargo, Rita Monteiro; Tardelli, Daniel Teixeira; Turra, Alexander

    2014-10-01

    The structure, dynamics and production of two populations of the olivid gastropod Olivella minuta were analyzed through monthly sampling from November 2009 through October 2011 on two sandy beaches, Pernambuco (very sheltered) and Barequeçaba (sheltered) in São Paulo state (23°48'S), southeastern Brazil. On both beaches, samples were taken along five transects established perpendicular to the waterline. Parameters of the von Bertalanffy growth function were estimated for both populations from monthly length-frequency distributions. The production and turnover ratios were determined using the mass-specific growth rate method. The population on the less-sheltered Barequeçaba Beach was less abundant (120.02 ± 22.60 ind m-1) than on Pernambuco Beach (3295.30 ± 504.86 ind m-1 (±SE)), which we attribute to the greater environmental stability of the latter. Conversely, the mean length, size of the largest individual, and body mass were higher at Barequeçaba than at Pernambuco. The significant differences in the growth of individuals and the mortality rate (Z) between the beaches suggest that density-dependent processes were operating at Pernambuco Beach. The production and P/B ratio at Pernambuco (12.12 g AFDM m-1 year-1 and 1.91 year-1) were higher than at Barequeçaba (0.82 g AFDM m-1 year-1 and 1.06 year-1). The difference in production can be attributed to the higher abundance on Pernambuco, while the higher P/B ratio resulted from the scarcity of smaller individuals in the intertidal zone of Barequeçaba. The P/B ratio estimated for the Pernambuco population is the highest found so far for sandy-beach gastropods. This study reinforces the theory that biological interactions are important regulators of sheltered sandy-beach populations. Future studies with multi-beach sampling are needed to better understand the life-history variations of O. minuta along gradients of degree of exposure of sandy beaches.

  4. Imposex in Olivancillaria vesica vesica (Gmelin (Gastropoda, Olividae from a Southeastern Brazilian sandy beach

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    Carlos Henrique Soares Caetano

    2002-12-01

    Full Text Available Imposex, the development of male sex organs on the female, is registered and described for Olivancillaria vesica vesica (Gmelin, 1791 at Restinga da Marambaia beach, Rio de Janeiro state, Brazil.

  5. Eine neue Deroceras-Art (Gastropoda, Pulmonata, Agriolimacidae) von der Griechischen Insel Samos

    NARCIS (Netherlands)

    Rähle, W.

    1983-01-01

    Im Frühjahr 1982 sammelte Herr Jens Hemmen aus Wiesbaden (Bundesrepublik Deutschland) auf der Insel Samos zahlreiche Individuen einer noch unbekannten Deroceras-Art, die ihren anatomischen Merkmalen nach zur Untergattung Plathystimulus Wiktor, 1973 gehört. Die Tiere waren fast alle erwachsen und erm

  6. Caracoles terrestres (Mollusca: Gastropoda) de Iturbide, Nuevo León, México

    OpenAIRE

    Correa Sandoval, Alfonso

    2015-01-01

    Catorce especies de caracoles terrestres son informadas del municipio de Iturbide, Nuevo León, México. El tipo de vegetación más rico en moluscos (11 especies) es el bosque de galería de Populus-Quercus-Juglans, con cobertura vegetal total y escasa pendiente. La distribución panamericana es el principal componente zoogeográfico Fourteen species of land snails are reported from the municipality of Iturbide, Nuevo León, México. The vegetation type with more species ( 1 1) is the Populus-Quer...

  7. Ecomorphological Analyses of Marine Mollusks' Shell Thickness of Rapana venosa (VALENCIENNES, 1846 (Gastropoda: Muricidae

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    Igor P. Bondarev

    2013-10-01

    Full Text Available Shell thickness of Rapana venosa was investigated from ecologically different places of the Azov – Black Sea basin. In the formation of the shell thickness there are two major trends: thickening with age, and inversely proportional to the size of the thickening of even-aged individuals of the same population. Shell thickness formation was analyzed in connection with biotic and abiotic environmental factors of influence. R. venosa ontogeny is not conducive to the rapid succession newly acquired characters in local populations. The formation of a thick shell is mainly the individual response of bions to the environment. Individuals’ of the same type reaction is the cause of formation of specific conchological characters of separate populations or parts thereof. Mechanical impacts (e.g. damage by breaking predators and storm waves hitting on rocks have no significant effect on the increasing of thickness of shells. Comparative analysis of the thickness of the shell of R. venosa from areas with different salinity shows that the direct relationship between these parameters is absent. R. venosa is capable of forming its own salinity medium in the mantle cavity, which is different from the external environment. The main factor influencing the formation of a thick-walled shell is the amplitude of the temperature fluctuations in the locality. Shell thickness of R. venosa was considered as ecomorphological character in comparison with the same feature of shell-bearing mollusks from the World Ocean at different latitude zones. It is shown that high temperature gradient is one of the most important factors of forming a thick shell. The greatest show this intertidal species and ecomorphs of temperate and high latitudes, where the temperature gradients are most expressed.

  8. Well-known and little-known: miscellaneous notes on Peruvian Orthalicidae (Gastropoda, Stylommatophora)

    NARCIS (Netherlands)

    Breure, A.S.H.; Mogollón Avila, V.

    2010-01-01

    The family Orthalicidae is well represented in Peru but, like in other families, some species are wellknown and others have not been reported on since their original descriptions. In this paper we present new records for well-known species and elucidate the status of several lesser known taxa. Four

  9. Alien Planorbid (Mollusca, Gastropoda Pulmonata) from South West Africa erroneously recorded as Biomphalaria Pfeifferi

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1974-01-01

    In 1970 I published a record of the freshwater snail Biomphalaria pfeifferi (Krauss, 1848) (fam. Planorbidae) for South West Africa: "Sandamap Farm, Spitzkoppe" (Van Bruggen, 1970: 45, figs. 1-13). Dr. D. S. Brown of the Medical Research Council (London) kindly drew my attention to the fact that jud

  10. A new genus and species of Aclididae (Gastropoda) from off Tenerife, Canary Islands

    NARCIS (Netherlands)

    Moolenbeek, R.G.; Warén, A.

    1987-01-01

    Dr. Manuel Carrillo Pèrez (Universidad de la Laguna) has sent some dredge-samples to the first author. This material contained many interesting molluscs, not mentioned by Nordsieck & Talavera (1979). Amongst them was a very peculiar gastropod species, which was difficult to identify. Based on some s

  11. Histofisiología del epitelio renal de helix aspersa (mollusca, gastropoda, pulmonata, stylommatophora)

    OpenAIRE

    Sánchez Aguayo, Inmaculada

    1983-01-01

    La excreción es, por definición, la separación de los productos de desecho de los fluidos tisulares y corporales, y su eliminación del organismo. Además, se considera como el resultado de la filtración del líquido de la sangre, de la reabsorción de ciertos compuestos y de la secreción de sustancias en el interior de túbulos excretores. Los productos de desecho son el resultado del metabolismo celular. Aunque en general son productos finales de procesos catabólicos, también pueden incluir ...

  12. Iron-encrusted diatoms and bacteria epibiotic on Hydrobia ulvae (Gastropoda: Prosobranchia)

    Science.gov (United States)

    Gillan, D. C.; Cadée, G. C.

    2000-02-01

    Rust-coloured shells of the gastropod Hydrobia ulvae collected in the Wadden Sea near Texel and in the Jade Busen were analysed under the scanning electron microscope. Most of the shells were found to be covered with a microbial community encrusted with an iron-rich mineral containing traces of Mn, Mg, Ca and Si (EDAX analysis). The community formed a biofilm including two morphotypes of diatoms identified as Cocconeis placentula and Achnanthes lemmermanni, two morphotypes of slender filamentous bacteria resembling Leucothrix and Flexibacter, aggregates of coccoid cells and large trichomes resembling members of the cyanobacterial orders Pleurocapsales and Stigonematales, respectively. The most frequent microorganisms of the biofilm were diatoms and filamentous bacteria.

  13. Size clines and subspecies in the Streptaxid Genus Gulella PFR. (Mollusca, Gastropoda pulmonata) in Southern Africa

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1980-01-01

    CONTENTS 1. Introduction.................. 3 2. Systematic part................. 6 Gulella adamsiana................. 7 Gulella darglensis................. 14 Gulella elliptica................. 19 Gulella farquhari................. 27 Gulella infrendens................ 33 Gulella planti.............

  14. Biological aspects of Omalonyx convexus (Mollusca, Gastropoda, Succineidae from the Rio Grande do Sul State, Brazil

    Directory of Open Access Journals (Sweden)

    Janine Oliveira Arruda

    2011-12-01

    Full Text Available Omalonyx convexus (Heynemann, 1868 is widely spread throughout the Rio Grande do Sul State, Brazil. The studied specimens presented in vivo, tegument and mantle coloring in variations between milky-white, orange and beige. The shell presented itself covered by the mantle in different extents; however, it was not completely covered on any of the specimens. The feeding diet is basically constituted by vegetal tissues, although non-vegetal food items were also found. The specimens were found in preserved and in polluted fresh water environments, as well as on natural and artificial substrates. The temperature throughout the day influences their placement on habitat substrates.

  15. [Effect of an altered magnetic field on the development of great ramshorn Planorbarius corneus (Gastropoda, Planorbidae)].

    Science.gov (United States)

    Tsetlin, V V; Zotin, A A; Moĭsa, S S

    2014-01-01

    Effects of a 100-300-fold attenuated geomagnetic field on the embryonic development of great ramshorn Planorbarius corneus and water oxidation-reduction properties were studied in a hypomagnetic chamber. The hypomagnetic field was largely favorable to the P. corneus development. Specifically, teratogenic effects were less massive, i.e. embryos that had known no other environment but hypomagnetism were characterized by low death rate. The agility index grew in embryos on the stages of late veliger and post-metamorphosis. A sharp increase of the magnetic field to the normal strength resulted in rapid death of embryos and juvenile mollusks (virtually, their growth was arrested). Type of induction was dependent on adaptation of juvenile P. corneus to a magnetic field. Mollusks grown in the normal geomagnetic field would prefer the conditions with maximal induction, whereas mollusks developed in the hypomagnetic chamber, on the contrary, chose the conditions with minimal induction. The oxidation-reduction potential of water increased as magnetic induction attenuated pointing to a natural decline in internal energy of water molecules due, as we see it, to inhibition of the mollusk embryonic development.

  16. Limnaea peregrina Clessin, 1882, Synonym of Lymnaea columella Say, 1817 (Gastropoda: Lymnaeidae

    Directory of Open Access Journals (Sweden)

    W Lobato Paraense

    1994-12-01

    Full Text Available A description is given of the shell, radula, renal region, reproductive system and egg capsules of topotypic specimens of limnaea peregrina Clessin, 1882. This investigation intends contributing to define the specific identity of that nominal species. A close anatomical comparison with Lymnaea columella Say, 1817 from Michigan, USA, shows that both forms are indistinguishable, giving support to previous inferences from some authors. Data on egg hatching are presented.

  17. A new species of hydrobiid snails (Mollusca, Gastropoda, Hydrobiidae from central Greece

    Directory of Open Access Journals (Sweden)

    Canella Radea

    2011-10-01

    Full Text Available A new minute valvatiform species belonging to the genus Daphniola Radoman 1973, Daphniola eptalophos sp. n., from mountain Parnassos, Greece is described. The new species has a transparent valvatiform-planispiral shell, wide and open umbilicus, grey-black pigmented soft body and head and a black penis with a small colorless outgrowth on the left side near its base. A comparative table of shell dimensions and a key to the species known for this endemic genus for Greece are provided.

  18. Locomotion of Stramonita haemastoma (Linnaeus (Gastropoda, Muricidae on a mixed shore of rocks and sand

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    Marcos G. Papp

    2001-03-01

    Full Text Available Mixed shores of rocks and sand are appropriate systems for the study of limitations that the isolation of rocks may impose for gastropods that typically inhabit rocky shores. We marked 52 Stramonita haemastoma (Linnaeus, 1767 snails on a mixed shore and found that 34 of them moved between rocks one to four times during 15 surveys in a period of 72 days. In the experiments, the snails moved on rock by continuous, direct, ditaxic, alternate undulations of the foot sole but on submerged sand they used slower arrhythmic discontinuous contractions of the foot sole. They switched between modes of locomotion in response to the type and topography of the substrate and possibly to water dynamics. In nature, snails moved between rocks forming aggregations where they oviposited. This may have masked other causes of movement, such as availability of prey. Most snails burrowed into the sand when the rocks became exposed during low tides. Further experiments are needed to explicitly address the possible causes of movements among rocks and burial.

  19. Linking immune patterns and life history shows two distinct defense strategies in land snails (gastropoda, pulmonata).

    Science.gov (United States)

    Russo, Jacqueline; Madec, Luc

    2013-01-01

    Life history integration of the defense response was investigated at intra- and interspecific levels in land snails of the family Helicidae. Two hypotheses were tested: (i) fitness consequences of defense responses are closely related to life history traits such as size at maturity and life span; (ii) different pathways of the immune response based on "nonspecific" versus "specific" responses may reflect different defense options. Relevant immune responses to a challenge with E. coli were measured using the following variables: blood cell density, cellular or plasma antibacterial activity via reactive oxygen species (ROS) level, and bacterial growth inhibition. The results revealed that the largest snails did not exhibit the strongest immune response. Instead, body mass influenced the type of response in determining the appropriate strategy. Snails with a higher body mass at maturity had more robust plasma immune responses than snails with a lower mass, which had greater cell-mediated immune responses with a higher hemocyte density. In addition, ROS appeared also to be a stress mediator as attested by differences between sites and generations for the same species.

  20. Activity of the mangrove snail Cerithidea decollata (Gastropoda: Potamididae) in a warm temperate South African estuary

    Science.gov (United States)

    Hodgson, Alan N.; Dickens, John

    2012-08-01

    A population of Cerithidea decollata, an intertidal marine gastropod usually found within mangroves, was studied within an area of Juncus kraussii in the upper reaches of the warm temperate Knysna estuary, which is at the southern-most limit of the recorded distribution of this snail. Activity (migratory and homing behaviour, distances travelled during foraging) of the snails was monitored over spring and neap tides in four seasons. Migratory patterns of the snails were affected by season, time of low tide (day vs night), tidal magnitude (spring vs neap) and zonation. In the summer and spring, a greater proportion of snails migrated from J. kraussii leaves onto the mud during the day at spring low tide. During neap tides in these two seasons, most snails did not climb J. kraussii leaves and remained on the mud, which was nearly always exposed. In autumn a few snails only were active and in winter snails were almost completely inactive, probably due to low air temperatures. Snails travelled greater distances on the mud on spring tides, during the diurnal low tides, and in the summer. No snails were found to home to individual J. kraussii leaves; however, homing behaviour was recorded to wooden poles within the Juncus wetland.

  1. Organ- and species-specific accumulation of metals in two land snail species (Gastropoda, Pulmonata)

    Energy Technology Data Exchange (ETDEWEB)

    Boshoff, Magdalena, E-mail: magdalena.boshoff@ua.ac.be [University of Antwerp, Systemic Physiological and Ecotoxicological Research, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Jordaens, Kurt [Royal Museum for Central Africa (JEMU), Leuvensesteenweg 13, B-3080 Tervuren (Belgium); University of Antwerp, Evolutionary Ecology Group, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Backeljau, Thierry [University of Antwerp, Evolutionary Ecology Group, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Royal Belgian Institute of Natural Sciences (JEMU), Vautierstraat 29, B-1000 Brussels (Belgium); Lettens, Suzanna [Research Institute for Nature and Forest (INBO), Kliniekstraat 25, B-1070 Brussels (Belgium); Tack, Filip [Ghent University, Laboratory of Analytical Chemistry and Applied Ecochemistry, Coupure Links 265, B-9000 Ghent (Belgium); Vandecasteele, Bart [Institute for Agricultural and Fisheries Research (ILVO), Burg van Gansberghelaan 109, B-9820 Merelbeke (Belgium); De Jonge, Maarten; Bervoets, Lieven [University of Antwerp, Systemic Physiological and Ecotoxicological Research, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)

    2013-04-01

    In order to evaluate the usefulness of terrestrial gastropods as bioindicators there is a need for studies that simultaneously compare (1) concentrations of metals in reference and polluted plots, (2) species within the same polluted habitat, (3) metal accumulation patterns in different organs and (4) metal accumulation patterns in relation to soil physicochemical properties. This study aims to assess metal accumulation patterns in two land snail species. Instead of analyzing an organism as a whole, investigating the partitioning of metals in different organs can provide information on the actual toxicological relevant fractions. Therefore, concentrations of Ag, Cd, Cr, Cu, Ni and Zn were examined in five different organs of Cepaea nemoralis, as well as in the foot and the body of Succinea putris. Snails were sampled at four polluted dredged sediment disposal localities and three adjacent less polluted reference plots situated along waterways in Flanders, Belgium. Due to the small size and problematic dissection of S. putris only the concentrations in the foot of both species could be compared. For this reason only, C. nemoralis can be described as a better bioindicator species that allows a far more detailed analysis of organ metal accumulation. This study showed that organs other than the digestive gland may be involved in the immobilization and detoxification of metals. Furthermore, pH, soil fractionation (clay %, silt %, sand %) and organic matter, correlate with metal accumulation in organs. However, most often the soil metal concentrations did not correlate with the concentrations found in snail organs. Metal concentrations in organs of both species (1) differed among polluted plots but rarely between polluted and reference plots within a locality, (2) were organ-specific (digestive gland > foot > albumen gland = spermoviduct = ovotestis), (3) were species-specific and (4) depended on the metal type (high Cd and Cu concentrations were observed in the digestive gland and foot respectively). Our study emphasizes that background metal levels should be taken into account when using invertebrates as bioindicators of metal contamination and that bioindicators may show substantial differences in accumulation patterns even if they have a highly comparable ecology. - Highlights: ► Concentrations of accumulated metals differ among localities and between the snail species in the foot. ► Organs other than the digestive gland may be involved in the immobilization and detoxification of metals. ► Total metal concentrations and soil physicochemical properties alone are not enough to explain organ bioaccumulation.

  2. Atlanta ariejansseni, a new species of shelled heteropod from the Southern Subtropical Convergence Zone (Gastropoda, Pterotracheoidea)

    Science.gov (United States)

    Wall-Palmer, Deborah; Burridge, Alice K.; Peijnenburg, Katja T.C.A.

    2016-01-01

    Abstract The Atlantidae (shelled heteropods) is a family of microscopic aragonite shelled holoplanktonic gastropods with a wide biogeographical distribution in tropical, sub-tropical and temperate waters. The aragonite shell and surface ocean habitat of the atlantids makes them particularly susceptible to ocean acidification and ocean warming, and atlantids are likely to be useful indicators of these changes. However, we still lack fundamental information on their taxonomy and biogeography, which is essential for monitoring the effects of a changing ocean. Integrated morphological and molecular approaches to taxonomy have been employed to improve the assessment of species boundaries, which give a more accurate picture of species distributions. Here a new species of atlantid heteropod is described based on shell morphology, DNA barcoding of the Cytochrome Oxidase I gene, and biogeography. All specimens of Atlanta ariejansseni sp. n. were collected from the Southern Subtropical Convergence Zone of the Atlantic and Indo-Pacific oceans suggesting that this species has a very narrow latitudinal distribution (37–48°S). Atlanta ariejansseni sp. n. was found to be relatively abundant (up to 2.3 specimens per 1000 m3 water) within this narrow latitudinal range, implying that this species has adapted to the specific conditions of the Southern Subtropical Convergence Zone and has a high tolerance to the varying ocean parameters in this region. PMID:27551204

  3. Present distribution of Potamopyrgus antipodarum (Gray, 1843 (Mollusca: Gastropoda in the Slovak Republic

    Directory of Open Access Journals (Sweden)

    Tomáš Čejka

    2008-02-01

    Full Text Available All published and known unpublished data on Potamopyrgus antipodarum (Gray, 1843 from the Slovak Republic are summarised. The Slovak distribution is restricted to the southern parts of the country close to the Danube, Morava, and Hron Rivers. Geographic and vertical distribution is described. The most of the localities are placed between 100 and 140 m a.s.l., the highest situated known record was in 277 m a.s.l. P. antipodarum inhabits slowly flowing rivers and different types of standing waters in Slovakia.

  4. Neuromuscular development of Aeolidiella stephanieae Valdéz, 2005 (Mollusca, Gastropoda, Nudibranchia

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    Klussmann-Kolb Annette

    2010-01-01

    Full Text Available Abstract Background Studies on the development of the nervous system and the musculature of invertebrates have become more sophisticated and numerous within the last decade and have proven to provide new insights into the evolutionary history of organisms. In order to provide new morphogenetic data on opisthobranch gastropods we investigated the neuromuscular development in the nudibranch Aeolidiella stephanieae Valdéz, 2005 using immunocytochemistry as well as F-actin labelling in conjunction with confocal laser scanning microscopy (cLSM. Results The ontogenetic development of Aeolidiella stephanieae can be subdivided into 8 stages, each recognisable by characteristic morphological and behavioural features as well as specific characters of the nervous system and the muscular system, respectively. The larval nervous system of A. stephanieae includes an apical organ, developing central ganglia, and peripheral neurons associated with the velum, foot and posterior, visceral part of the larva. The first serotonergic and FMRFamidergic neural structures appear in the apical organ that exhibits an array of three sensory, flask-shaped and two non-sensory, round neurons, which altogether disappear prior to metamorphosis. The postmetamorphic central nervous system (CNS becomes concentrated, and the rhinophoral ganglia develop together with the anlage of the future rhinophores whereas oral tentacle ganglia are not found. The myogenesis in A. stephanieae begins with the larval retractor muscle followed by the accessory larval retractor muscle, the velar or prototroch muscles and the pedal retractors that all together degenerate during metamorphosis, and the adult muscle complex forms de novo. Conclusions Aeolidiella stephanieae comprises features of the larval and postmetamorphic nervous as well as muscular system that represent the ground plan of the Mollusca or even the Trochozoa (e. g. presence of the prototrochal or velar muscle ring. On the one hand, A. stephanieae shows some features shared by all nudibranchs like the postmetamorphic condensation of the CNS, the possession of rhinophoral ganglia and the lack of oral tentacle ganglia as well as the de novo formation of the adult muscle complex. On the other hand, the structure and arrangement of the serotonergic apical organ is similar to other caenogastropod and opisthobranch gastropods supporting their sister group relationship.

  5. Estudo morfométrico da concha de Lymnaea columella say, 1817 (Mollusca, Gastropoda, Pulmonata

    Directory of Open Access Journals (Sweden)

    Marlene T. Ueta

    1980-12-01

    Full Text Available Foram estudadas variações morfométricas de conchas de L. columella, provenientes de dez criadouros localizados nos seguintes municípios do Estado de São Paulo: - Campinas, Americana, Atibaia, Pirassununga, Caçapava e Taubaté. Foram analisados os diferentes tipos de ambientes onde as limneas são encontradas com maior freqüência, estabelecendo-se a época do ano com maior abundância em espécimes, que correspondeu aos meses de julho a outubro. As medidas nas conhas dos diferentes criadouros referiram-se ao comprimento e largura da concha, comprimento e largura da abertura, comprimento da espira e número de voltas. Foram estabelecidos os coeficientes de correlação e de regressão e realizadas análises de variância entre as medidas tomadas e os índices obtidos da relação entre largura/comprimento da concha. Estas conchas foram comparadas com as de L. columella, L. viator, L. cubensis da coleção do Museu Nacional do Rio de Janeiro. Para a maioria das medidas as conchas mostraram proporções constantes, embora apresentassem diferenças em relação ao desenvolvimento. A maior variação foi observada em relação ao comprimento da espira. As variações morfométricas das conchas foram relacionadas com alguns fatores externos como pH, alcalinidade, dureza e teor da água. Aparentemente apenas a dureza total da água influiu na consistência das conchas.Shells of Lymnaea columella from ten populations from the State of São Paulo were studied to determine morphometric variation. Samples were collected in the following municipalities: Campinas, Americana, Atibaia, Pirassununga, Caçapava and Taubaté. Five measurements were taken from each shell: length and width of the shell, length and width of the aperture and lenght of the spire. Two ratios were also established: width/lenght of the shell and length of the aperture /length of the shell. The numbers of whorls and the length of the shell were also determined. Statistical tests (correlation coeficients, regression, and analysis of variance were used to compare the different samples. Also, com parisons of L. columella shells collected by us were made with those of L. columella, L. viator and L. cubensis from collections deposited in the Museu Nacional, Rio de Janeiro. The results of these studies revealed that in most of the cases the snail populations of different areas were similar, showing constant proportions, but they diverged in their absolute dimensions. Data on aquatic environmental conditions (pH, alkalinity, hardness, and calcium concentration were also obtained. These Chemical factors were examined with respect to shell morphology. Our results revealed that only hardness of water was associated with the robustness of the shells.

  6. New Odostomia species (Gastropoda, Heterobranchia, Pyramidellidae) from the Miocene Pebas Formation of Western Amazonia (Peru, Colombia)

    NARCIS (Netherlands)

    Aartsen, van J.J.; Wesselingh, F.P.

    2000-01-01

    Odostomia nuttalli spec. nov. and O. coluhensis spec. nov. are described from the Miocene Pebas Formation of Peruvian and Columbian Amazonia. A third pyramidellid snail is also diagnosed. These species are indicators for marine influence in the late Middle to early Late Miocence of Western Amazonia.

  7. Anatomia e histologia do conduto genital feminino de Pomacea canaliculata (Lamarck, 1822 (Mollusca, Gastropoda, Pilidae

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    Eliana de Fátima Marques de Mesquita

    1990-01-01

    Full Text Available In this paper the authors give an anatomical and histological analysis of the genital duct in mature and immature females of Pomacea canaliculata (Lamarck, 1822. Anatomically, the vagina has an equal dimension in its extension, varying in form and volume, according to the maturation period. In the immaturity, it has a smaller diameter and volume. In the maturity, the vagina increases in volume, having the aspect of a tumescent organ, and in certain specimens shows an albuminous pink thread in its lumen. Histologically, the calcigenic activity of the gland is evidentiated by the presence of an amorphous and basophilic mass, without nuclear material. This material has a fragmented aspect in the vagina lumen that reacts positively in van Kossa's coloured preparations for calcareous salts.

  8. Taxonomic review of Metaxia (Gastropoda: Triphoridae from Brazil, with description of a new species

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    Maurício Romulo Fernandes

    2011-12-01

    Full Text Available The taxonomy of the species of Metaxia Monterosato, 1884 from Brazil is revised. Previously to this study, only Metaxia excelsa Faber & Moolenbeek, 1991 was known to occur in this country, under its older name Metaxia exilis (C.B. Adams, 1850. The review of a large amount of shells in malacological collections in Brazil revealed the occurrence of three known additional species: Metaxia taeniolata (Dall, 1889; Metaxia rugulosa (C.B. Adams, 1850; Metaxia prompta Rolán & Fernández-Garcés, 2008, all previously reported from the southeast coast of the USA and/or the Caribbean region. Metaxia gongyloskymnus sp. nov., diagnosed by the globose protoconch with continuous axial ribs and microscopic spiral sculpture, is restricted to localities off the Southeastern Brazilian coast.

  9. Results of the Rumphius Biohistorical Expedition to Ambon. Part 9. The Nassariidae (Mollusca: Gastropoda)

    NARCIS (Netherlands)

    Kool, H.H.; Strack, H.L.

    1999-01-01

    This paper lists all species of the family Nassariidae collected during the Rumphius Biohistorical Expedition to Ambon (1990). Altogether 47 species are reported, of which two, Nassarius maccauslandi and N. rotundus, are new for Indonesia. Four additional species from Ambon are known from collection

  10. The phylogeny and taxonomy of austral monodontine topshells (Mollusca: Gastropoda: Trochidae), inferred from DNA sequences.

    Science.gov (United States)

    Donald, Kirsten M; Kennedy, Martyn; Spencer, Hamish G

    2005-11-01

    The systematics of topshells (family Trochidae) is currently unresolved: at present even the generic boundaries within this group are poorly defined. In this study, we used sequence data of two mitochondrial genes (16S and cytochrome oxidase 1, COI) and one nuclear gene (actin) to resolve the phylogeny of a closely related subgroup of the Trochidae, 30 species of largely Southern Hemisphere monodontine topshells. The phylogenies constructed revealed five well-supported generic clades: a South African clade (genus Oxystele Philippi, 1847), which lay basally to four internal Pacific clades (genera Chlorodiloma Pilsbry, 1889; Monodonta Lamarck, 1799; Austrocochlea Fischer, 1885; and Diloma Philippi, 1845). The molecular phylogenies constructed in this study shed light on previously unresolved relationships between different groups of topshells, allowing for the first time assignation (based on DNA sequence) of clearly defined, well-supported taxonomic and nomenclatural classification of monodontine topshells species. Austrocochlea crinita (Philippi, 1849), A. odontis (Wood, 1828), A. adelaidae (Philippi, 1849), and A. millelineata (Bonnet, 1864) are placed in the genus Chlorodiloma, which we resurrect from synonymy with Austrocochlea. The Japanese M. confusa Tapparone-Canefri, 1874 is treated as a separate species from M. labio (Linné, 1758). Melagraphia Gray, 1847 is synonymised with Diloma and its sole member, M. aethiops (Gmelin, 1791), along with A. concamerata (Wood, 1828), is transferred to that genus. The Juan Fernandez endemic D. crusoeana (Pilsbry, 1889) is synonymised with D. nigerrima (Gmelin, 1791). We find that morphologically cryptic species are not necessarily close genetically.

  11. Late Paleozoic subulitacea (mollusca:gastropoda), mass extinctions and the replacement of evolutionary faunas

    Energy Technology Data Exchange (ETDEWEB)

    Erwin, D.H.

    1985-01-01

    Mesogastropod subulitaceans possess characteristics typical of active carnivores and occupied a trophic regime typical of the Mesozoic-Cenozoic evolutionary fauna. Despite occupying a vacant niche, subulitaceans are low in both diversity and abundance in late Paleozoic gastropod faunas. In addition, Paleozoic Archaeogastropoda and Mesogastropoda are taxonomically and functionally distinct from Mesozoic groups and display diversity dynamics typical of the Paleozoic evolutionary fauna, not the Mesozoic-Cenozoic fauna with which they were grouped by Sepkoski. Late Paleozoic gastropods are different from pre-Carboniferous taxa, but there is no preferential expansion of the major Mesozoic taxa, nor is there any pattern of exploitation of a major niche utilized by later groups but under-used by Paleozoic taxa. The high taxonomic level used Sepkoski's factor analysis neglects the finer scale of replacement and diversification. This distinct evolutionary behavior of Paleozoic gastropods may be typical of other taxa as well. It weakens the assertions of Kitchell and Carr and Sepkoksi and Miller that the replacement of evolutionary Fauna II by Fauna III began in the late Paleozoic and would have occurred even without the Guadelupian-Dzulfian mass extinction. Thus for gastropods at last, the Late Permian mass extinction did not merely speed up on ongoing process, but probably determined the evolutionary outcome.

  12. Integrative taxonomy of the genus Onchidium Buchannan, 1800 (Mollusca, Gastropoda, Pulmonata, Onchidiidae

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    Benoît Dayrat

    2016-11-01

    Full Text Available In an effort to clarify the species diversity of onchidiid slugs, the taxonomy of the genus Onchidium Buchannan, 1800 is revised using an integrative approach. New, fresh specimens were collected in a large number of places, including type localities. The genus Onchidium is redefined here as a clade including only three species which are strongly supported by both morphological and molecular data. All three species were already named: the type species O. typhae Buchannan, 1800, O. stuxbergi (Westerlund, 1883, and O. reevesii (J.E. Gray, 1850. With the exception of a re-description of O. typhae published in 1869, all three species are re-described here for the first time. First-hand observations on the color variation of live animals in their natural habitat are provided. The anatomy of each species is described. Important nomenclatural issues are addressed. In particular, Labella Starobogatov, 1976 is regarded as a junior synonym of Onchidium and Labella ajuthiae (Labbé, 1935 and O. nigrum (Plate, 1893 are regarded as junior synonyms of O. stuxbergi. The nomenclatural status of several other species names is discussed as well. Many new records are provided across South-East Asia and precise ranges of geographic distributions are provided for the genus Onchidium and its three species. Distinctive features that help distinguish the genus Onchidium from other onchidiids are provided, as well as an identification key for the three species.

  13. Two new species of Thaumastus (Gastropoda: Pulmonata: Orthalicidae: Bulimulinae from the state of Minas Gerais, Brazil

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    Meire Silva Pena

    2011-08-01

    Full Text Available Two new species of Thaumastus (Thaumastus from the state of Minas Gerais, southeastern Brazil, are described. They are diagnosed and characterized by the morphology of the shell and soft parts and compared with Brazilian species of the subgenus Thaumastus s.s. Martens, 1860. Thaumastus (T. parvus sp. nov. is similar to T. (T. baixoguanduensis Pena, Coelho & Salgado, 1996 but can be distinguished by the smaller size, smaller number of plates in the jaw, different number of follicle groups in the ovotestis and form of the fertilization complex. Thaumastus (T. caetensis sp. nov. is similar to T. (T. largillierti (Philippi, 1845 but differs by the width and the contour of the parietal side of the shell aperture. T. (T. caetensis is also closer to Thaumastus (T. baixoguanduensis but can be distinguished by the smaller dimensions (height, width and number of protoconch whorls, the lack of a transversal light band on the body whorl, the jaw with smaller number of plates, and the radula with 35 teeth. In the soft parts, this new species differs also in the number of follicle gatherings in ovotestis, fertilization complex with globose shape, and penian retractor muscle terminally and laterally attached to flagellum

  14. Thecosomata e Gymnosomata (Mollusca, Gastropoda da cadeia Fernando de Noronha, Brasil

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    Larrazábal Maria Eduarda de

    2003-01-01

    Full Text Available The Mollusca Pteropoda from Fernando de Noronha Chain Northeastern Brazil were studied in order to know their taxonomy and distribution. Collections were carried out during the I Oceanographical Expedition of the REVIZEE Program (Live Resources of the Economical Exclusive Zone from August to September 1995. The studied area is located between 03°04'S-04°23'S and 32°19'W-36°26'W, comprising 35 stations. Sampling was performed through oblique hauls from 50m depth to surface and from 100 m depth to surface, with a Bongo net (300 and 500 µm mesh size, net diameter: 60 cm, that was equipped with a flow meter. Samples in a total of 99 were preserved, immediately, in buffered 4% formaldehyde. Qualitative and quantitative analyses of the samples were performed based on total sample. The samples were analysed on a counting plate "Bogorov" type under a stereo microscope. A total of 8,258 organisms were identified belonging to: 8 families, 16 genera and 27 species. Limacina inflata (d´Orbigny, 1836 and Creseis virgula (Rang, 1828 were frequent and very frequent in the area outranking among the studied Pteropoda. The total density varied from 2.5 to 3,012.05 org.m-³. Highest richness was registered at the Continental Shelf and Slope with 1two species. The Pteropoda association showed higher differences between day and night collections. Limacina inflata caused this difference due to its higher density at night collections and it was independent of the depth, mesh size and temperature. Creseis virgula had its occurrence, mainly, during day time.

  15. Streptaxidae (Mollusca: Gastropoda: Pulmonata) of the Seychelles Islands, Western Indian Ocean

    NARCIS (Netherlands)

    Gerlach, J.; Bruggen, van A.C.

    1999-01-01

    The taxonomy of the species of the terrestrial carnivorous snail family Streptaxidae of the Seychelles archipelago is reviewed with the exception of the three species of the genus Priodiscus (vide Gerlach, 1995). All 18 species are restricted to the northern, granitic islands. This paper describes 1

  16. Defensive allomones in three species ofHypselodoris (gastropoda: Nudibranchia) from the Cantabrian sea.

    Science.gov (United States)

    Fontana, A; Avila, C; Martinez, E; Ortea, J; Trivellone, E; Cimino, G

    1993-02-01

    ThreeHypselodoris species,H. villafranca, H. cantabrica, and H. tricolor, have been studied in order to further investigate the defensive strategies of Chromodorididae mollusks from Iberian coasts. All animals possess large amounts of furanosesquiterpenoids, probably derived from their diet of sponges. The products are transferred and stored in specific sites of the mantle (mantle dermal formations, MDFs) to be used as chemical deterrents against predators. Chemical analysis of CantabrianHypselodoris species has led to the characterization of eight sesquiterpenoids. Among these, six have been found previously in both sponges and nudibranchs, while two are new natural products.Hypselodoris species cooccurring in the same area contained comparable mixtures of sesquiterpenoids. However, two populations ofH. cantabrica from different sites of the Cantabrian sea showed different metabolic patterns. All sesquiterpenoids induce feeding deterrence inCarassius auratus and two are also toxic toGambusia affinis.

  17. COMPARATIVE SPERM ULTRASTRUCTURE IN FIVE GENERA OF THE NUDIBRANCH FAMILY CHROMODORIDIDAE (GASTROPODA: OPISTHOBRANCHIA).

    Science.gov (United States)

    Wilson, NERIDA G.; Healy, JOHN M.

    2002-05-01

    Sperm ultrastructure is examined in representatives of five genera of the nudibranch gastropod family Chromodorididae: (Chromodoris, Hypselodoris, Glossodoris, Risbecia and Pectenodoris) and the results compared with previous work on other gastropods, especially other nudibranchs. As chromodoridid phylogeny is still incompletely understood, this study partly focuses on the search for new and as yet untapped sources of informative characters. Like spermatozoa of most other heterobranch gastropods, those of the Chromodorididae are elongate, complex cells composed of an acrosomal complex (small, rounded acrosomal vesicle, and columnar acrosomal pedestal), a condensed nucleus, sub-nuclear ring, a highly modified mid-piece (axoneme + coarse fibres surrounded by a glycogen-containing, helically-coiled mitochondrial derivative) and terminally a glycogen piece (or homologue thereof). The finely striated acrosomal pedestal is a synapomorphy of all genera examined here, but interestingly also occurs in at least one dorid (Rostanga arbutus). Substantial and potentially taxonomically informative differences were also observed between genera in the morphology of the nucleus, the neck region of the mid-piece, and also the terminal glycogen piece. The subnuclear ring is shown for the first time to be a segmented, rather than a continuous structure; similarly, the annular complex is shown to consist of two structures, the annulus proper and the herein-termed annular accessory body.

  18. Not so sluggish: the success of the Felimare picta complex (Gastropoda, Nudibranchia) crossing Atlantic biogeographic barriers.

    Science.gov (United States)

    Almada, Frederico; Levy, André; Robalo, Joana I

    2016-01-01

    The molecular phylogeny of the Atlanto-Mediterranean species of the genus Felimare, particularly those attributed to the species F. picta, was inferred using two mitochondrial markers (16S and COI). A recent revision of the Chromodorididae clarified the taxonomic relationships at the family level redefining the genus Felimare. However, conflicting taxonomic classifications have been proposed for a restrict group of taxa with overlapping morphological characteristics and geographical distributions designated here as the Felimare picta complex. Three major groups were identified: one Mediterranean and amphi-Atlantic group; a western Atlantic group and a tropical eastern Atlantic group. F. picta forms a paraphyletic group since some subspecies are more closely related with taxa traditionaly classified as independent species (e.g. F. zebra) than with other subspecies with allopatric distributions (e.g. F. picta picta and F. picta tema). Usually, nudibranchs have adhesive demersal eggs, short planktonic larval phases and low mobility as adults unless rafting on floating materials occurs. Surprisingly however, the phylogeny of the F. picta complex suggests that they successfully cross main Atlantic biogeographic barriers including the mid-Atlantic barrier. This ability to cross different biogeographic barriers may be related to F. picta's distinct life history and ecological traits. Compared to other Chromodorididae F. picta has larger eggs and planktotrophic larvae which could be related to a longer planktonic phase.

  19. Not so sluggish : The success of the Felimare picta complex (Gastropoda, Nudibranchia) crossing Atlantic biogeographic barriers

    OpenAIRE

    2016-01-01

    The molecular phylogeny of the Atlanto-Mediterranean species of the genus Felimare, particularly those attributed to the species F. picta, was inferred using two mitochondrial markers (16S and COI). A recent revision of the Chromodorididae clarified the taxonomic relationships at the family level redefining the genus Felimare. However, conflicting taxonomic classifications have been proposed for a restrict group of taxa with overlapping morphological characteristics and geographical distribut...

  20. The invasive Chinese mystery snail Bellamya chinensis (Gastropoda: Viviparidae expands its European range to Belgium

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    Van den Neucker Tom

    2017-01-01

    Full Text Available In this paper we report the first Belgian records of the invasive Chinese mystery snail Bellamya chinensis. A walkover-survey along the Laak, a small lowland river, yielded a total of 20 live B. chinensis. The presence of both juvenile and adult individuals, with a shell height ranging from 16.6 to 47.5 mm, indicates that the species is firmly established. The most probable source of introduction is a nearby garden center that specializes in ornamental fish and plants for garden ponds.

  1. Synonymy between Lymnaea bogotensis Pilsbry, 1935 and Lymnaea cousini Jousseaume, 1887 (Gastropoda: Lymnaeidae

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    Luz Elena Velásquez

    2006-11-01

    Full Text Available The lymneid snail Lymnaea bogotensis Pilsbry 1935 is synonymized with L. cousini Jousseaume 1887, based on morphological comparisons of the reproductive systems. The shell, renal tube, and reproductive system are described and illustrated from specimens collected in the type locality and the municipality of Paipa, Colombia. Bibliographical records reveal L. columella to be the commonest lymneid in the country. The latter two species can be differentiated based on the morphology of the penial complex.

  2. Delimitation and phylogenetics of the diverse land snail family Urocoptidae (Gastropoda: Pulmonata): A reunion with Cerion

    NARCIS (Netherlands)

    Uit de Weerd, Dennis R.

    2010-01-01

    The extreme morphological diversity in the land-snail family Urocoptidae has complicated its delimitation from other land-snail families, and has obscured its intra- and interfamilial phylogenetic relationships. Using an independent dataset of 28S rRNA DNA-sequence data, I tested morphologybased hyp

  3. A new species of Leiostracus from Bahia, Brazil (Gastropoda, Pulmonata, Orthalicidae

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    Rodrigo B. Salvador

    2014-03-01

    Full Text Available A remarkable new species of pulmonate snail was recently collected in a small Atlantic Rainforest fragment near the city of Canavieiras, state of Bahia, Brazil, an area known for a high diversity of land snails. It is described herein as Leiostracus fetidus sp. nov. and can be easily identified by its color pattern of irregular brown to black axial stripes on a white to yellow background, a reddish axial band "separating" the white peristome from the rest of the shell and a broad brown spiral band surrounding the umbilical region. Other diagnostic features include a relatively small size, a proto columellar fold and two very weak folds delimiting the basal region of the aperture. This discovery is a reminder of how little this fauna is known and also an alarm for proper conservation of these forest fragments.

  4. Belgrandiella bozidarcurcici n. sp., a new species from Bosnia and Herzegovina (Gastropoda: Hydrobiidae

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    Glöer P.

    2014-01-01

    Full Text Available A new hydrobiid snail, Belgrandiella bozidarcurcici n. sp., is described from the rheocrene and rheopsammocrene springs situated in the canyon of the Cvrcka River, a region of Banja Luka, Republic of Srpska, Bosnia and Herzegovina. The concept of the genus Belgrandiella seems to be extremely artificial, but for the time being we keep the new species as a member of the genus based mainly on the shape of the shell of its type species, B. kusceri (Wagner, 1914.

  5. A new species of Leiostracus (Gastropoda, Pulmonata, Orthalicoidea from Espírito Santo, Brazil

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    Rodrigo B. Salvador

    2014-09-01

    Full Text Available A remarkable new species of pulmonate land snail was found in the collection of the Senckenberg Forschungninstitut und Naturmuseum Frankfurt (Frankfurt am Main, Germany and is described here as Leiostracus faerie sp. nov. It can be easily identified by its small and translucent shell with fine axial light brown bands and its protoconch sculpture. It was collected in the Rio Doce ("Doce River" region in Espírito Santo, Brazil, an area known for a high diversity and endemicity of land snails. This discovery shows how little this fauna is known and reinforces the importance of museum collections in the study of biodiversity and conservation.

  6. MUDWHELKS (GASTROPODA: POTAMIDIDAE FROM MANGROVES OF UJUNG KULON NATIONAL PARK, BANTEN

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    NOVA MUJIONO

    2014-08-01

    Full Text Available A study of Potamididae snail from the mangrove ecosystem in Ujung Kulon National Park was conducted, regarding to its diversity, shell characters and habitat characters. This study was carried out in 2008 during drought and rainy season. At the eight stations observed, seven species and four genera of Potamididae snail were identified. Compared with previous study, this study added new information from obtaining one genus (Cerithidea of three species (Cerithidea weyersi, C. quadrata and Cerithideopsilla alata

  7. A new species of the operculate land snail genus Maizaniella from Liberia (Gastropoda, Caenogastropoda)

    NARCIS (Netherlands)

    Winter, de A.J.

    2009-01-01

    Maizaniella sapoensis spec. nov. from Liberia is described. The species is provisionally att ributed to the subgenus Spirulozania. It is by far the smallest known member of the genus, with an adult shell diameter of just over 2 mm.

  8. Radix natalensis (Gastropoda: Lymnaeidae, a potential intermediate host of Fasciola hepatica in Egypt

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    Dar Y.

    2010-09-01

    Full Text Available Experimental infections of Egyptian Radix natalensis with French miracidia of Fasciola hepatica were carried out to determine if this snail might act as an intermediate host in the life cycle of this digenean in Egypt. Single exposures of R. natalensis to miracidia (2/snail and two successive exposures (a total of 4 miracidia/snail were performed using lymnaeids measuring 1 to 6 mm in height. Live larval forms of F. hepatica were noted in single- and double-exposed snails. In double exposures, a significant increase of snail survival on day 28 post-exposure (at 24 °C and an decrease in prevalence were noted when the height of snails at exposure was increasing. Cercariae of F. hepatica were shed by these snails (90.7/snail during a mean patent period of 24.3 days. All snails have released these cercariae during 2-13 waves of shedding. According to these results, R. natalensis can be considered a potential intermediate host of F. hepatica in Egypt.

  9. Quantification of midkine gene expression in Patella caerulea (Mollusca, Gastropoda) exposed to cadmium

    Science.gov (United States)

    Stillitano, Francesca; Mugelli, Alessandro; Cerbai, Elisabetta; Vanucci, Silvana

    2007-10-01

    The release of cadmium into many coastal areas represents a threat to ecosystems and human health; cadmium is carcinogenic in mammals and in both marine invertebrates and vertebrates. The use of molluscs to assess the ecologic risk associated with contaminants is strongly recommended on account of their ecological role and on their highly conserved control and regulatory pathways that are often homologous to vertebrate systems. We previously identified a midkine family protein in the limpet Patella caerulea; the midkine is a recently discovered cytokines family with unequivocal informative value on repairing injury and neoplastic processes in mammals. Here we report on midkine ( mdk) and α-tubulin ( α-tub) gene expression patterns in P. caerulea exposed to cadmium. Limpets, collected on two occasions from a breakwater at a marina (Tyrrhenian Sea) were exposed to sublethal cadmium concentrations (0.5 and 1 mg l -1 Cd) over a 10-day exposure period. RNA was extracted from the viscera of unexposed and exposed specimens. Real time TaqMan RT-PCR was performed to measure the relative mdk and α-tub gene expression levels. A remarkable mdk over-expression was observed in all exposed animals with respect to unexposed ones; mdk over-expression was significantly higher in both treatments when compared with un-treatment (mean expression levels: 23- and 38-fold, for 0.5 and 1 mg l -1 Cd treatment, respectively; ANOVA, for both P < 0.01). The study also indicates that the mdk up-regulation was significantly Cd-concentration dependent ( P < 0.05). A significant up-regulation of the constitutive α-tub gene was also observed in 1 mg l -1 Cd-treated animals (mean expression level: 4-fold; ANOVA, P < 0.05). In conclusion, these data provide the first evidence paving the way for the use of the midkine as a promising new biomarker of effect in the environment risk assessment policy.

  10. Identification of Shell Colour Pigments in Marine Snails Clanculus pharaonius and C. margaritarius (Trochoidea; Gastropoda.

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    S T Williams

    Full Text Available Colour and pattern are key traits with important roles in camouflage, warning and attraction. Ideally, in order to begin to understand the evolution and ecology of colour in nature, it is important to identify and, where possible, fully characterise pigments using biochemical methods. The phylum Mollusca includes some of the most beautiful exemplars of biological pigmentation, with the vivid colours of sea shells particularly prized by collectors and scientists alike. Biochemical studies of molluscan shell colour were fairly common in the last century, but few of these studies have been confirmed using modern methods and very few shell pigments have been fully characterised. Here, we use modern chemical and multi-modal spectroscopic techniques to identify two porphyrin pigments and eumelanin in the shell of marine snails Clanculus pharaonius and C margaritarius. The same porphyrins were also identified in coloured foot tissue of both species. We use high performance liquid chromatography (HPLC to show definitively that these porphyrins are uroporphyrin I and uroporphyrin III. Evidence from confocal microscopy analyses shows that the distribution of porphyrin pigments corresponds to the striking pink-red of C. pharaonius shells, as well as pink-red dots and lines on the early whorls of C. margaritarius and yellow-brown colour of later whorls. Additional HPLC results suggest that eumelanin is likely responsible for black spots. We refer to the two differently coloured porphyrin pigments as trochopuniceus (pink-red and trochoxouthos (yellow-brown in order to distinguish between them. Trochopuniceus and trochoxouthos were not found in the shell of a third species of the same superfamily, Calliostoma zizyphinum, despite its superficially similar colouration, suggesting that this species has different shell pigments. These findings have important implications for the study of colour and pattern in molluscs specifically, but in other taxa more generally, since this study shows that homology of visible colour cannot be assumed without identification of pigments.

  11. Examining the phylogeny of the Australasian Lymnaeidae (Heterobranchia: Pulmonata: Gastropoda) using mitochondrial, nuclear and morphological markers.

    Science.gov (United States)

    Puslednik, Louise; Ponder, Winston F; Dowton, Mark; Davis, Andrew R

    2009-09-01

    We examined the species groups relationships of the freshwater snail genus Austropeplea using mitochondrial, nuclear and morphological markers in addition to traditional methods of shell shape analysis. Based primarily on the results of a combined molecular and morphological analysis, samples of the nominal species A. tomentosa form distinct lineages. The New Zealand populations of A. tomentosa are a very distinct lineage from any of the Australian populations attributed to A. tomentosa. Furthermore, within the Australian group, three lineages, south Australia, Tasmania and eastern Australia, appear to have undergone recent and/or rapid speciation events. Samples assigned to A. lessoni were resolved as two distinct lineages, representing the eastern and northern Australian populations. Kutikina hispida was resolved within the Australian A. tomentosa clade. Molecular results for A. viridis suggests that it is also composed of at least two distinct lineages that could be treated as species. Incongruence observed between the single mitochondrial, nuclear and morphological topologies highlight the importance of using a number of different datasets in the delimitation of species-group taxa.

  12. Veränderung der Erkennungsspezifität ausgewählter Restriktions-Modifikationssysteme aus dem Bodenbakterium Herpetosiphon giganteus

    OpenAIRE

    Falgenhauer, Linda

    2012-01-01

    Das Ziel dieser Arbeit war es, die natürliche Bildung eines neuen Restriktions-Modifikationssystem anhand des Beispiels der als nicht klonierbar geltenden S176N Mutante des Restiktionsenzyms R.HgiBI nachzuahmen. Die Nichtklonierbarkeit dieser Mutante sollte dabei entweder durch eine neue Spezifität oder durch eine im Vergleich zum Wildtyp erhöhte Aktivität hervorgerufen werden, die nicht mehr durch die Methyltransferase M.HgiBI abgedeckt wird. Als Untersuchungsobjekt boten sich die drei s...

  13. Can the exceptional chilling tolerance of C4 photosynthesis found in Miscanthus × giganteus be exceeded? Screening of a novel Miscanthus Japanese germplasm collection

    DEFF Research Database (Denmark)

    Glowacka, Katarzyna; Jørgensen, Uffe; Kjeldsen, Jens Bonderup

    2015-01-01

    of this study was to search for genotypes with greater potential than Mxg for photosynthesis and frost survival under these conditions. Methods A total of 864 accessions representing 164 local populations of M. sacchariflorus (Msa), M. sinensis (Msi) and M. tinctorius (Mti) collected across Japan were studied...... at chilling temperatures were identified. Msa accession ‘73/2’ developed leaves in the spring that survived night-time frost, and during growth under chilling maintained a statistically significant 79 % higher ΦCO2,max, as a measure of light-limited photosynthesis, and a 70 % higher Asat, as a measure...... of light-saturated photosynthesis. A second Msa accession, ‘73/3’ also showed significantly higher rates of leaf uptake of CO2. Conclusions As remarkable as Mxg has proved in its chilling tolerance of C4 photosynthesis, this study shows that there is still value and potential in searching for yet more...

  14. Conducta de forrajeo del gastrópodo Acanthina monodon Pallas, 1774 (Gastropoda: Muricidae en el intermareal rocoso de Chile central Foraging behavior of the gastropod Acanthina monodon Pallas, 1774 (Gastropoda: Muricidae in the intertidal rocky shores of central Chile

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    RUBÉN E. SOTO

    2004-03-01

    Full Text Available En el presente trabajo investigamos aspectos de la ecología y conducta de forrajeo de Acanthina monodon, un gastrópodo murícido que habita en el intermareal rocoso de Chile central. En terreno, estudiamos las variaciones temporales en su distribución, densidad y dieta. En el laboratorio, cuantificamos la tasa de consumo, las preferencias alimentarias, el tiempo de ingestión y la rentabilidad energética obtenida con distintos tipos de presas mediante experimentos y registros en video. Las mayores densidades de individuos de A. monodon fueron observadas en la franja intermareal cercana al nivel cero de marea. En terreno, A. monodon realiza sus actividades de forrajeo principalmente durante la noche y su dieta consistió principalmente de mitílidos (95 % y cirripedios (5 %. La composición de la dieta de A. monodon en terreno presentó variaciones temporales las cuales dependerían principalmente de cambios en la oferta de los distintos tipos de mitílidos presentes en terreno durante los dos años de muestreo. En el laboratorio, los individuos de Acanthina presentaron preferencias alimentarias significativas por el mitílido Semimytilus algosus. En general, A. monodon bajo condiciones de laboratorio presentó una conducta de forrajeo en la cual maximizó la ganancia neta de energía, mediante la selección de las especies y tamaños de presas que le retribuyen la mayor rentabilidad energéticaWe investigated the ecology and foraging behavior of Acanthina monodon, a muricid gastropod that inhabits in the intertidal rocky shores of central Chile. In the field, we studied temporal variation of their spatial distribution, density, and diet composition. While in the laboratory, we quantified the consumption rate, alimentary preferences, ingestion times and energy profitability obtained with different types of prey using experiments and video recording. High densities of A. monodon individuals were observed in the intertidal fringe near at the level tide zero. In the field, A. monodon actively foraged at night preying mainly on mussels (95 % and barnacles (5 %. Temporal variation in diet composition of A. monodon was caused mostly by changes in the cover of different mussel species during the two years of sampling. In the laboratory, individual of A. monodon showed significant preference for the mussel Semimytilus algosus. In these experiments, A. monodon's foraging behavior maximized the net gain of energy by selecting species and sizes of prey that provided the greatest energy profitability

  15. Genetical exchanges between one Biomphalaria glabrata (Gastropoda: Planorbidae and a varying number of partners Trocas genéticas entre uma Biomphalaria glabrata (Gastropoda: Planorbidae e um número variado de parceiros

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    Marc Vianey-Liaud

    1987-12-01

    Full Text Available When one pigmented Biomphalaria glabrata is mated with 1 to 20 albino snails, the percentage of albino parent producing pigmented offspring decreases while the percentage of parent laying albino offspring increases. If the number of snaisl/group increases, the mean duration of the use of allosperm decreases.Quando uma Biomphalaria glabrata pigmentada é posta em presença de um a vinte parceiros albinos, a percentagem de indivíduos parentais que produzem, por fecundação cruzada, uma descendência pigmentada, decresce. Ao contrário, a proporção de indivíduos parentais cuja descendência é de albinos aumenta. Quando o número de caramujos albinos por grupo aumenta, a duração média da utilização dos espermatozóides estranhos recebidos do parceiro pigmentado decresce.

  16. Prosobrânquios terrestres do Brasil: Cyclophoridae: Neocyclotus (N. agassizi (Bartsch & Morrison, 1942 (Mollusca, Gastropoda, Mesogastropoda Land prosobranchs of Brazil: Cyclophoridae: Neocyclotus (N. agassizi (Bartsch & Morrison, 1942 (Mollusca, Gastropoda, Mesogastropoda

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    Arnaldo C. dos Santos Coelho

    1989-01-01

    Full Text Available Studies on specimens from Brazil (States of Pernambuco and Alagoas were carried out in order to relate data about morphology of hard and soft parts o Nocyclotus (N. agassizi (Bartsh & Morrison, 1942.

  17. Primeiro registro de Antillorbis nordestensis (Lucena (Mollusca, Gastropoda, Planorbidae para a Ilha Grande, Angra dos Reis, Rio de Janeiro First record of Antillorbis nordestensis (Lucena (Mollusca, Gastropoda, Planorbidae to Ilha Grande, Angra dos Reis, Rio de Janeiro

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    Sônia Barbosa dos Santos

    1999-01-01

    Full Text Available A malacological survey has been done by the sênior author in Ilha Grande, State of Rio de Janeiro, since 1996. Up to this date the only freshwater gastropods found were specimens of Antillorbis nordestensis (Lucena, 1954. The snails were collected at a swampy area situated behind the late Penal Colony Cândido Mendes (Ilha Grande Prison.

  18. La Familia Trochidae (Mollusca: Gastropoda en el norte de Chile: consideraciones ecológicas y taxonómicas The trochidae family (Mollusca : Gastropoda in northern Chile: taxonomic and ecological considerations

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    DAVID VELIZ

    2000-12-01

    Full Text Available Este estudio describe la diversidad, y la distribución latitudinal y batimétrica de los caracoles de la Familia Trochidae en el norte de Chile, mediante muestreos intermareales y submareales someros, realizados entre 1996 y 1999 entre Arica (18º S y Los Vilos (31º S, y de muestras de profundidad provenientes de la pesca de arrastre del camarón nylon, Heterocarpus reedi. En el norte de Chile, la Familia Trochidae está representada por cuatro géneros: Tegula y Diloma de distribución intermareal y submareal somero hasta los 20 m de profundidad, y Bathybembix y Calliostoma presentes en profundidades superiores a los 200 m. El género Tegula tiene seis especies (T. quadricostata, T. luctuosa, T. ignota, T. atra, T. tridentata y T. euryomphala distribuídas en sustratos rocosos intermareales y submarales someros. El género Diloma está representado por una especie, D. nigerrima, de distribución intermareal hasta pocos metros de profundidad. El género Calliostoma tiene dos especies C. chilena y C. delli, las que se distribuyen entre 200 y 750 m de profundidad. Finalmente, el género Bathybembix está representado por B. humboldti y B. macdonaldi distribuídas entre 200 y 1480 m de profundidad. Esta segregación batimétrica parece estar relacionada a las estrategias alimentarias de cada uno de los géneros de la familia Trochidae. Diloma y Tegula son herbívoros, las especies del género Bathybembix son alimentadoras de depósito y las de Calliostoma son carnívorasThis study reveals the diversity, and the bathimetric and latitudinal distribution of the snails of the Trochidae family members in northern Chile, throughout the analysis of all Trochidae gastropods entailed in intertidal and subtidal (from the `camarón naylon' fishery samples collected during 1996 and 1999 between Arica (ca 18º S and Los Vilos (ca 31º S. The Trochidae family in northern Chile have four genus: Tegula and Diloma that are distributed on intertidal and shallow subtidal habitats, and Calliostoma and Bathybembix which occurr at dephts greather than 200 m. Tegula have 6 species: T. quadricostata, T. luctuosa, T. ignota, T. atra, T. tridentata, and T. euryomphala are distributed on intertidal and shallow subtidal habitats. Diloma is a monospecific genus, whereas D. nigerrima is an intertidal species. The genus Calliostoma have two species C. chilena and C. delli occurring between 200 and 750 m depth and the Bathybembix with two species, B. Humboldti and B. macdonaldi, distributed between 200 and 1480 m depth. The bathimetric distribution of Trochidae shows a strong correlation with food strategy: Diloma and Tegula are herbivores, while Bathybembix species are deposit feeders and Calliostoma are carnivores

  19. Desenvolvimento de Eurytrema coelomaticum (Giard & Billet (Digenea, Dicrocoeliidae em Bradybaena similaris (Férussac (Gastropoda, Xanthonychidae Development of Eurytrema coelomaticum (Giard & Billet (Digenea, Dicrocoeliidae in Bradybaena similaris (Férussac (Gastropoda, Xanthonychidae

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    Solange Viana Paschoal Blanco Brandolini

    2001-06-01

    Full Text Available To follow the larval developmenl of Eurytrema coelomaticum (Giard & Billet, 1892 in Bradybaena similaris (Férussac, 1821 snails were separated in three classes using the shell diameter: Class A (14.5-10.2 mm, Class B (10.1-6.9 mm and Class C (6.8-2.6 mm. Only snails belonging to classes A and B acquired the infection. Specimens of E. coelomaticum removed from the pancreatic ducts were exposed to three physiological solutions: Earle, Locke and saline 0.85%, to obtain eggs for the experimental infections, The Locke solution induced the best egg release. The route of migration the intramolluscan development of E. coelomaticum was studied with the aid of histology. The minimal period of intramolluscan developmenl, ending at the expelling of daughter sporocysts, was 107 days for the snails infected in March, and 79 days for the snails infected in November. The Student "t" test and the Chi-square test showed a significant difference (α = 5% between the two periods, although the mean temperature registered during the experiments did not significantly differed (α = 5%. The elimination of daughter sporocysts occurred through the snail's pneumostome, and always at night. Most sporocysts were eliminated at intervals that varied between one to three days, without regularity. The time of elimination of the daughter sporocysts was different for the two infection period studied: 12 weeks for the snails infected in March, and three weeks for those infected in November. Positive correlation between the number of sporocysts expelled by the snail host and higher temperatures registered in the laboratory was observed. This correlation was more evident in November infection.

  20. Estudo quantitativo de metais presentes na hemolinfa de Biomphalaria glabrata (Gastropoda, infectadas e não infectadas com Schistosoma mansoni Quantitative study of metal present in the hemolymph of Biomphalaria glabrata (Gastropoda, infected and uninfected with Schistosoma mansoni

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    Marco Antonio Vasconcelos Santos

    2005-04-01

    Full Text Available Inicialmente, desenvolveu-se um estudo para quantificar e comparar as concentrações de alguns metais presentes em duas amostras de hemolinfa do caramujo Biomphalaria glabrata (infectados e não-infectados com Schistosoma mansoni. A espectrometria de emissão óptica com fonte de plasma induzido (ICP-OES, foi utilizada para analisar os metais nas duas amostras. Os metais estudados foram: alumínio, cálcio, cádmio, cobalto, cromo, cobre, ferro, potássio, magnésio, manganês, chumbo e zinco. Os resultados mostram que, a princípio, os metais não são fatores determinantes no processo de defesa desses organismos contra este parasita, quando presente nos seus tecidos.We conducted a preliminary study to quantify and compare two concentrations of the same metals present in the hemolymph of snail Biomphalaria glabrata. In this context, we used Induction Coupled Plasma Optical Emission Spectroscopy technique (ICP-OES, to analyze the metals in the two samples (snails infected and not infected with Schistosoma mansoni. The metals studied were: aluminum, calcium, cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, lead and zinc. Preliminary results showed that such metals are not involved in the defense of these organisms against the parasite, when present in their tissues.

  1. Microanatomia e histologia do sistema digestivo de Phyllocaulis soleiformis (Orbigny (Mollusca, Gastropoda, Veronicellidae: V. Glândula digestiva Microanatomy and histology of the digestive system of Phyllocaulis soleiformis (Orbigny, 1835 (Mollusca, Gastropoda, Veronicellidae: V. Digestive gland

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    Ana Maria Leal-Zanchet

    1993-01-01

    Full Text Available The digestive gland of Phyllocaulis soleiformis is a compound tubular gland. The secretory tubules are made up of two main cell types: the digestive cells and calcic cells. The digestive cells are the most numerous, usually columnar, and exhibit three different functional stages: absorptive, secretory and excretory. These cells contain two cytoplasmic granules types and, in the excretory stage, most of the cell is occupied by a large vacuole. The calcic cells occursingly or frequently in groups of two or three, are triangular shaped and have distinct apical granules, and yet calcic histochemical detected granules. In addition, there is a third cell type, without characteristic cytoplasmic granules and which correspond to the undifferentiated cells. The excretory duets system are represented by anterior and posterior vestibules, which branche to form the duets, that communicate with the secretory tubules. These excretory duets are lined with a simple epithelium of ciliated columnar cells, followed by a layer of connective tissue with circular and longitudinal muscular fibers. Subepithelial mucous cells are present only in the vestibules.

  2. Os gêneros Fasciolaria Lamarck, 1799 e Leucozonia Gray, 1847 no nordeste brasileiro (Mollusca: Gastropoda: Fasciolariidae The genera Fasciolaria Lamarck, 1799 and Leucozonia Gray, 1847 in the northeastern Brazil (Mollusca: Gastropoda: Fasciolariidae

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    Helena Matthews-Cascon

    1989-01-01

    Full Text Available The genera Fasciolaria Lamarck, 1799 and Leucozonia Gray, 1847 are represented in Northeastern Brazil by three species. Fasciolaria aurantiaca Lamarck, 1816; Leucozonia ocellata (Gmelin, 1791 and Leucozonia nassa (Gmelin, 1791. The three species are described and illustrated. An identification key for all the above mentioned taxa is included, together with some ecological data. The anatomy and radula of Fasciolaria aurantiaca and Leucozonia nassa are described and illustrated. Polimorfism in Fasciolaria aurantiaca and Leucozonia nassa is discussed.

  3. Parámetros reproductivos y poblacionales de Thais chocolata (Duelos, 1832 (Gastropoda, Thaididae, en la reserva marina La Rinconada, Antofagasta, Chile Reproductive and population parameters of Thais chocolata (Duclos, 1832 (Gastropoda, Thaididae in La Rinconada marine reserve, Antofagasta, Chile

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    Marcela Cantillánez

    2011-11-01

    Full Text Available Para obtener antecedentes reproductivos y poblacionales de Thais chocolata que contribuyan a validar su actual normativa pesquera, se realizó un estudio en el área protegida de la reserva marina La Rinconada, Antofagasta, Chile, entre diciembre 2008 y enero 2010. Los resultados obtenidos indicaron a nivel reproductivo, que el desarrollo gonadal de la población es asincrónico, encontrándose ejemplares en diferentes etapas de maduración durante el año. Los individuos maduros se estratificaron entre 5 y 13 m de profundidad, y gran parte del año formaron agregaciones a 5 m de profundidad. Se determinaron períodos de mayor madurez en julio-agosto, y en noviembre-enero, manifestándose las agregaciones más importantes al final de ellos. Una relación se observó entre meses de mayor madurez y registro de agregaciones, con aquellos de mayor variación intradiaria de temperatura. A nivel poblacional los resultados permitieron estimar una población de 2,3*10(6 ejemplares, donde el 39% se encontró sobre la talla mínima legal (TML = 55 mm. Los parámetros de crecimiento mostraron crecimiento relativamente lento, que podría estar influenciado por la alta variabilidad que presenta la temperatura de fondo en este sector. Mientras que su talla crítica, y la talla de primera madurez sexual poblacional, resultaron ser mayores a la TML. Se determinó la necesidad de revisar la normativa pesquera actual de esta especie, y se demostró la efectividad de las reservas marinas propiciadas por el Estado en la conservación de los recursos marinos.Reproductive and population parameters of Thais chocolata that would contribute to the validation of the current extraction standards were obtained by performing a study in the protected area of La Rinconada Marine Reserve, Antofagasta, Chile, from December 2008 to January 2010. In terms of reproduction, the results revealed asynchronic gonad development in the population, with specimens in different stages of maturity throughout the year. Mature individuals were distributed between 5 and 13 m depth, forming aggregations at 5 m depth during much of the year. Periods of greater maturity were observed from July to August and November to January, with the most important aggregations at the end of both periods. A relationship was observed between the months with the greatest maturity and aggregations and the months with the highest daily temperature fluctuations. At the population level, the results allowed us to estimate 2.3*10(6 individuals, with 39% of this population over the minimum legal size (55 mm. The relatively slow growth estimated for this population was probably influenced by the high variability of the bottom temperature in this area. The critical size and size at first maturity of the population were higher than the minimal legal size, making it is necessary to review the current fishing regulation for this species. The effectiveness of the State marine reserves in the conservation of this marine resource was demonstrated.

  4. New species of Thaumastus from Lagoa Santa region, Minas Gerais State, Brazil (Mollusca, Gastropoda, Pulmonata, Bulimuloidea Nova espécie de Thaumastus da região de Lagoa Santa, Minas Gerais, Brasil (Mollusca, Gastropoda, Pulmonata, Bulimuloidea

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    Meire Silva Pena

    2005-03-01

    Full Text Available A new species of Thaumastus (Thaumastus Martens, 1860, from Minas Gerais State, Brazil, is described and illustrated, based on the morphology of the shell, jaw, radula and soft parts.Uma nova espécie de Thaumastus (Thaumastus Martens, 1860, do Estado de Minas Gerais, Brazil, é descrita e ilustrada, com base na morfologia da concha, mandíbula, rádula e partes moles.

  5. Anatomia e microanatomia do sistema reprodutor de Rectartemon (Rectartemon depressus (Heynemann (Mollusca, Gastropoda, Streptaxidae: complexo fálico Anatomy and microanatomy of the reproductive system of Rectartemon (Rectartemon depressus (Heynemann (Mollusca, Gastropoda, Streptaxidae: the phallus complex

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    Mônica Picoral

    1998-01-01

    Full Text Available It is described the anatomy and microanatomy of the phallus complex of Rectartemon depressus (Heynemann, 1868. The complex is composed by a phallus, a diverticle of the phallus and an epiphallus, where the deferens duct is thrown in: the retractor muscle is splitted in two parts, inserted into the region of the epiphallus through a smaller branch, and at the extremity of the diverticle, through a longer and thiner branch. The lumen of the phallus, epiphallus and diverticle have corrugations and thorns. On the phallus the thorns are arranged in a protuberance and disposed alternately in rows, ali with an aculeus form and with a chestnut collor point and a yellow basis.

  6. The effects of temperature and oxygen availability on intracapsular development of Acanthina monodon (Gastropoda: Muricidae El efecto de la temperatura y la disponibilidad de oxígeno sobre el desarrollo intracapsular de Acanthina monodon (Gastropoda: Muricidae

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    MIRIAM FERNÁNDEZ

    2006-06-01

    Full Text Available Freshwater and marine organisms show similar models of parental care and are faced with similar constraints to brood, which suggest that comparable environmental limits drive the evolution of parental care in aquatic systems. In fact, the low diffusion coefficient and solubility of oxygen in aquatic environments affect oxygen acquisition and therefore the capacity to aggregate embryos. The effect of other critical environmental variables, such as temperature, is less clear. We assessed the effects of temperature and oxygen availability on (1 the number of developed and undeveloped encapsulated embryos, (2 the proportion of embryos reaching advanced stages during intracapsular development (counting not only developed and undeveloped embryos but also abnormal embryos, (3 asynchrony in development (estimated only in capsules in which development occurred, and (4 final embryo size, as the first step toward identifying the main factors constraining parental care in the ocean. We used the gastropod Acanthina monodon as a model because it has an extended latitudinal range of distribution and exhibits feeding larvae during intracapsular development. The latter factor is relevant because previous studies have suggested that sibling cannibalism could be triggered by intracapsular competition for oxygen. Freshly laid egg capsules were collected and incubated until embryos hatched under different experimental temperatures (7, 11, 15 and 19 °C and oxygen conditions (hypoxia: 50-60 % air saturation; normoxia; and hyperoxia: 150-160 %. More embryos remained in early stages at the end of the experimental period under hypoxia and at the highest experimental temperature. The mean number of developed embryos was significantly lower under hypoxia conditions than under normoxia and hyperoxia, but was not influenced by temperature. However, temperature negatively affected embryo size of developed embryos and the level of asynchrony (number of different developmental stages per capsule. This suggests that even when a comparable number of embryos develops at high temperature, subsequent survival may be affected, since developed embryos attained smaller sizes. The negative effect of high temperature on embryo aggregation has also been reported for Brachyuran crabs, affecting female patterns of oxygen provision and brooding costs. This evidence suggests that aggregating embryos in the ocean, even under optimum oxygen conditions, may be negatively affected at high temperatures. Spatial patterns of distribution of brooding species in the ocean tend to agree with this prediction. Our analysis is particularly relevant given the current increase in temperature and the proportion of anoxic areas in the world's oceansLos organismos marinos y dulceacuícolas muestran modelos similares de cuidado parental y están confrontados con similares restricciones para incubar, lo que sugiere que existen límites ambientales comparables guiando la evolución del cuidado parental en sistemas acuáticos. El bajo coeficiente de difusión y la baja solubilidad del oxígeno en ambientes acuáticos afecta la adquisición de oxígeno y por lo tanto la capacidad para agregar los embriones. El efecto de otras variables ambientales críticas, como la temperatura, es menos claro. Se evaluaron los efectos de la temperatura y la disponibilidad de oxígeno sobre (1 el número de embriones desarrollados y sin desarrollar, (2 la proporción de embriones que alcanza estados avanzados de desarrollo (contabilizando no solo embriones desarrollados y sin desarrollar sino también anormales, (3 la asincronía en el desarrollo (estimada solo cuando ocurrió desarrollo embrionario, y (4 el tamaño final, con el objetivo final de identificar las limitaciones que estos factores imponen sobre el cuidado parental en el mar. La especie modelo fue el gastrópodo Acanthina monodon. Cápsulas recientemente depositadas fueron colectadas e incubadas bajo diferentes condiciones experimentales de temperatura (7, 11, 15 y 19 °C y oxígeno (hipoxia: 50-60 % saturación de aire; normoxia; e hiperoxia: 150-160 %. Más embriones permanecieron en fases tempranas del desarrollo al final del experimento en hipoxia y a 19 °C. El número promedio de embriones desarrollados fue significativamente más bajo en hipoxia que bajo normoxia e hiperoxia, pero no fue influenciado por la temperatura. Sin embargo, la temperatura de incubación afectó otras variables de respuesta. Menores tamaños de los embriones y mayores niveles de asincronía al final del desarrollo fueron observados en las más altas temperaturas experimentales, lo que podría tener consecuencias negativas sobre la sobrevivencia posasentamiento. Las altas temperaturas también afectan el comportamiento y los costos asociados a la provisión de oxígeno a los embriones en braquiuros. Estas evidencias sugieren que agregar embriones en el océano, aun en condiciones óptimas de oxígeno, podría ser desfavorable a altas temperaturas. Los patrones espaciales de distribución de especies incubadoras tienden a apoyar esta predicción. Nuestro análisis también cobra relevancia en el escenario actual de aumento de la temperatura media de los océanos y de la proporción de zonas anóxicas

  7. Field application of a set of cellular biomarkers in the digestive gland of the freshwater snail Radix peregra (Gastropoda, Pulmonata)

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    Guerlet, Edwige [Laboratoire Ecotoxicite, Sante Environnementale, CNRS UMR 7146, Universite de Metz, Rue General Delestraint, F-57070 Metz (France); Ledy, Karine [Laboratoire Ecotoxicite, Sante Environnementale, CNRS UMR 7146, Universite de Metz, Rue General Delestraint, F-57070 Metz (France); Giamberini, Laure [Laboratoire Ecotoxicite, Sante Environnementale, CNRS UMR 7146, Universite de Metz, Rue General Delestraint, F-57070 Metz (France)]. E-mail: giamb@sciences.univ-metz.fr

    2006-04-20

    An active biomonitoring study was performed in the vicinity of two pulp and paper mill effluents (PPMEs) released in two different streams in northeastern France. Freshwater gastropods, Radix peregra (=Lymnaea peregra or Lymnaea pereger), were transplanted for 0, 3, 14 and 21 days at two to three sites located upstream and downstream from the mill discharge points in both rivers. Lysosomal and peroxisomal systems, as well as lipofuscin and neutral lipids, were tested using histochemical methods on cryostat sections of digestive gland tissues, and stereological data were obtained by image analysis. Evidence of structural changes in the lysosomal system was found in animals exposed to both effluents, comprising general stress responses such as enlarged and more numerous lysosomes; and also possible specific pluri-phasic effects. Modifications of the lysosomal and cytoplasmic contents of lipid-related materials were also described, namely enhanced lipofuscin deposit and neutral lipid depletion. The peroxisomal proliferation in exposed snails seems to show its implication in oxidative stress detoxication, without preventing higher lipoperoxidation, as indicated by the increased amounts of digestive lipofuscin. Structural changes of the lysosomal and peroxisomal systems, digestive lipofuscin and neutral lipid contents have potential for use as early cellular biomarkers in Radix peregra exposed to environmental stressors, which deserve further investigations.

  8. Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda in the Museum für Naturkunde, Berlin

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    Abraham Breure

    2013-03-01

    Full Text Available The type status is described of 96 taxa classified within the superfamily Orthalicoidea and present in the Mollusca collection of the Museum für Naturkunde der Humboldt-Universität zu Berlin. Lectotypes are designated for the following taxa: Orthalicus elegans Rolle, 1895; Bulimus maranhonensis Albers, 1854; Orthalicus nobilis Rolle, 1895; Orthalichus tricinctus Martens, 1893. Orthalicus sphinx tresmariae is introduced as new name for Zebra sphinx turrita Strebel, 1909, not Z. quagga turrita Strebel, 1909. The following synonyms are established: Zebra crosseifischeri Strebel, 1909 = Orthalicus princeps fischeri Martens, 1893; Orthalicus isabellinus Martens, 1873 = O. bensoni (Reeve, 1849; Zebra zoniferus naesiotes Strebel, 1909 = Orthalicus undatus (Bruguière, 1789; Porphyrobaphe (Myiorthalicus dennisoni pallida Strebel, 1909 = Hemibulimus dennisoni (Reeve, 1848; Zebra delphinus pumilio Strebel, 1909 = Orthalicus delphinus (Strebel, 1909; Orthalicus (Laeorthalicus reginaeformis Strebel, 1909 = Corona perversa (Swainson, 1821; Bulimus (Eurytus corticosus Sowerby III, 1895 = Plekocheilus (Eurytus stuebeli Martens, 1885. The taxon Bulimus (Eudioptus psidii Martens, 1877 is now placed within the family Sagdidae, tentatively in the genus Platysuccinea. Appendices are included with an index to all the types of Orthalicoidea extant (including those listed by Köhler 2007 and a partial list of letters present in the correspondence archives.

  9. Thais (Stramonita rustica (Lamarck, 1822 (Mollusca: Gastropoda: Thaididae, a potential bioindicator of contamination by organotin northeast Brazil

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    Ítalo Braga de Castro

    2004-06-01

    Full Text Available The use of antifouling paints containing the biocide compound tributyltin (TBT has been shown as an inductor of imposex in neogastropods mollusks. Imposex is characterized by the development of male features in females, mainly the appearance of a no functional vas deferens and penis. Samples of Thais rustica were collected in eight sites in the metropolitan area of Natal city, Rio Grande do Norte state, northeast Brazil, and examined for occurrence of imposex, which was found in many females. The higher imposex levels were presented by samples from sites near city harbor.A utilização de tintas antiincrustrantes contendo o composto biocida tributilestanho (TBT tem induzido moluscos neogastrópodes ao imposex. O imposex é caracterizado pelo surgimento de caracteres sexuais masculinos, sobretudo, pênis e vaso deferente não funcionais em fêmeas desses moluscos. Foram coletadas amostras de Thais rústica em oito estações ao longo da costa da cidade de Natal no Rio Grande do Norte. Esses animais foram analisados quanto a presença e o grau de imposex que apresentavam. Os níveis mais elevados de imposex foram observados na estação mais próxima ao porto.

  10. Assessment of tributyltin contamination based on imposex in Stramonita rustica (Mollusca: Gastropoda along southern Bahia coast, northeastern Brazil

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    G. C. Zeidan

    Full Text Available Abstract This study investigated the effects of tributyltin (TBT on the morphology of the genital system of the gastropod Stramonita rustica in southern Bahia, Brazil. For this, 330 specimens were collected during the summer of 2014 at eight sampling points to ascertain whether male sex organs had developed in addition to the complete female genital tract in females (= imposex. The analyses were made under a stereoscopic microscope. Imposex and their associated indexes, and the sterile females, exhibited the highest rates in harbors and shipyards areas. Despite the total ban of TBT in anti-fouling paints on a global scale since 2003, the results of this and other studies indicate the continued use of those paints on the Brazilian coast. This shows the inefficiency of existing legislation and the need to strengthen enforcement of the ban.

  11. Imposex induction in Stramonita haemastoma floridana (Conrad, 1837 (Mollusca: Gastropoda: Muricidae submitted to an organotin-contaminated diet

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    Aline Fernandes Alves de Lima

    2006-03-01

    Full Text Available Marine organisms are affected by organotin compounds due to the cumulative, deleterious effects of these latter. The most evident and well known consequence of organotin contamination is imposex, a hormonal disruption that causes a superimposition of sexual male features in females of prosobranchia neogastropod molluscs such as Stramonita haemastoma floridana. Molluscs accumulate organotins mainly because of their poor ability to eliminate TBT and DBT from their tissues. The aim of this study was to analyze organotin uptake by ingestion experimentally, using uncontaminated subjects (S. haemastoma floridana fed with organotin-contaminated oysters (Crassostrea rhizophorae. A total of 248 gastropods, distributed in 7 tanks with uncontaminated water and contaminated food, were used in this study, a control group being fed uncontaminated oysters. Every 15 days, the individuals of one of the tanks were examined for the presence of imposex. Development of imposex was measured using the VDSI, RPSI and RPLI indexes. The animals had already developed imposex within the first 15 days, all the indexes measured (RPLI, RPSI and VDSI having increased significantly with duration of exposure, indicating that the animals were probablycontaminated by the food and had accumulated the pollutant. New paths of imposex development were also observed.Organismos marinhos são afetados por compostos organoestânicos que causam uma série de efeitos deletérios aos mesmos. O mais conhecido efeito da contaminação por organoestânicos é o imposex. Esse fenômeno consiste na masculinização de fêmeas de moluscos neogastrópodes tais como Stramonita haemastoma floridana. Esses compostos tendem a se acumular em moluscos devido a sua baixa capacidade de eliminá-los. Um total de 248 indivíduos de S. haemastoma floridana foram coletados de uma população livre qualquer indício de imposex. Esses animais foram mantidos em 7 aquários, com aproximadamente 30 indivíduos cada, 1 desses aquários foi considerado como controle e os animas do mesmo alimentados com ostras obtidas de locais onde não se verificou a ocorrência de imposex em neogastrópodes nativos. Os animais nos outros 6 aquários foram alimentados com ostras obtidas em local onde a incidência de imposex entre os gastrópodes nativos revelou-se muito alta. A cada 15 dias, por um período total de 90 dias, os animais de um dos tanques eram retirados e analisados quanto à presença de imposex. Os níveis de imposex foram quantificados através da % de imposex e dos índices: RPLI, RPSI e VDSI. Observou-se a indução de imposex em S. haemastoma floridana através da dieta a partir de Crassostrea rhizophora e um aumento significativo dos índices com o decorrer do tempo de exposição. Os animais do aquário controle foram analisados ao fim do experimento não revelando qualquer indício de imposex.

  12. Bioindicator Thais carinifera (mollusca, gastropoda: imposex response and consequences along the Pakistan coast during the period from 1993 to 2012

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    Nuzhat Afsar

    2015-06-01

    Full Text Available Abstract Endocrine mediated "imposex" phenomenon was investigated and recorded in the muricoid gastropod species Thais carinifera during the two decades from 1993 to 2012 at three (3 sites out of six (6 localities investigated along the Sindh and Balochistan coast, Pakistan. The VDS stages 1 to 4 were apparent in Thais carinifera. The intensity of imposex has remained comparatively low in the populations of harbours in close proximity to port Mohammad Bin-Qasim, namely; Old Korangi Fish Harbour (OKFH and New Korangi Fish Harbour (NKFH where shipping activities are sporadic as compared to those in Manora Channel and the adjoining Karachi Port area where intensive shipping activity is rather frequent. Target species found to be good bioindicators have shown a marked decrease over the prolonged study period. Investigations show that this decrease is solely due to globally imposed effective bans on tributyltin (TBT based antifouling paints over the past decade.

  13. Do climate variables and human density affect Achatina fulica (Bowditch) (Gastropoda: Pulmonata) shell length, total weight and condition factor?

    Science.gov (United States)

    Albuquerque, F S; Peso-Aguiar, M C; Assunção-Albuquerque, M J T; Gálvez, L

    2009-08-01

    The length-weight relationship and condition factor have been broadly investigated in snails to obtain the index of physical condition of populations and evaluate habitat quality. Herein, our goal was to describe the best predictors that explain Achatina fulica biometrical parameters and well being in a recently introduced population. From November 2001 to November 2002, monthly snail samples were collected in Lauro de Freitas City, Bahia, Brazil. Shell length and total weight were measured in the laboratory and the potential curve and condition factor were calculated. Five environmental variables were considered: temperature range, mean temperature, humidity, precipitation and human density. Multiple regressions were used to generate models including multiple predictors, via model selection approach, and then ranked with AIC criteria. Partial regressions were used to obtain the separated coefficients of determination of climate and human density models. A total of 1.460 individuals were collected, presenting a shell length range between 4.8 to 102.5 mm (mean: 42.18 mm). The relationship between total length and total weight revealed that Achatina fulica presented a negative allometric growth. Simple regression indicated that humidity has a significant influence on A. fulica total length and weight. Temperature range was the main variable that influenced the condition factor. Multiple regressions showed that climatic and human variables explain a small proportion of the variance in shell length and total weight, but may explain up to 55.7% of the condition factor variance. Consequently, we believe that the well being and biometric parameters of A. fulica can be influenced by climatic and human density factors.

  14. Susceptibility of tropical mountain forests to biological invasions from the temperate and subtropical zone, exemplified by Zonitoides (Gastropoda: Gastrodontidae)

    NARCIS (Netherlands)

    Capinha, Cesar; Vermeulen, Jaap J.; bin Lakim, Maklarin; Schilthuizen, Menno; Kappes, Heike

    2014-01-01

    Colonisation by, and spread of, animal species from the temperate zone are rather uncommon observations in the tropics. The study provides the first reports of two snail species of the genus Zonitoides in Sabah, Borneo, namely Z. arboreus (Say, 1819) and Z. nitidus (O.F. Muller, 1774). The identific

  15. Aberrant Forms of the Genus Clio Linnaeus, 1767, with a Review of the Genus Proclio Hubendick, 1951 (Gastropoda, Pteropoda)

    NARCIS (Netherlands)

    Spoel, S.v.d.

    1962-01-01

    The examination of two aberrant Pteropods collected during a trip with the whale factory-ship ”m.s. Willem Barendsz” led to the conclusion that they were animals in a resting stage. The histology and the anatomy of the totally aberrant soft parts was discussed. The shells of the specimens indicate t

  16. Keeping Nerves: Central Nervous System of the Interstitial Acochlidiid Parhedyle cryptophthalma (Gastropoda, Opisthobranchia)

    DEFF Research Database (Denmark)

    Joerger, Katharina; Kristof, Alen; Klussmann-Kolb, Annette

    2008-01-01

    Unusually well-preserved fossils of a Halicyne-like cycloid crustacean frequently occur in the early Late Triassic lacustrine clay bed at Krasiejów in Opole Silesia, southern Poland. Its gill-like structures form a horseshoe-shaped pair of units composed of numerous calcified blades with reverse ...

  17. Myogenesis in Aplysia californica (Cooper, 1863) (Mollusca, Gastropoda, Opisthobranchia) with special focus on muscular remodeling during metamorphosis

    DEFF Research Database (Denmark)

    Wollesen, Tim; Wanninger, Andreas; Klussmann-Kolb, Annette

    2008-01-01

    To date only few comparative approaches tried to reconstruct the ontogeny of the musculature in invertebrates. This may be due to the difficulties involved in reconstructing three dimensionally arranged muscle systems by means of classical histological techniques combined with light or transmissi...

  18. Standardization of a Patella spp. (Mollusca, Gastropoda) embryo-larval bioassay and advantages of its use in marine ecotoxicology.

    Science.gov (United States)

    Pérez, Sara; Fernández, Nuria; Ribeiro, Pedro A

    2016-05-01

    The use of three limpet species, Patella vulgata Linnaeus, 1758, Patella depressa Pennant, 1777 and Patella ulyssiponensis Gmelin, 1791 as model organisms in marine ecotoxicology has been evaluated. Initial laboratory experiments were aimed to standardize a biological test with embryos and larvae of Patella spp, establishing the percentage of normal trochophore larvae as endpoint. Before conducting in vitro fertilization, oocytes must be maturated artificially by incubation in an alkaline solution; therefore, alkalinizing agent, pH and time of eggs alkalinization were evaluated. Moreover, time of sperm activation, optimum sperm and oocytes concentration during fertilization, gamete contact time, use of stirring during the fertilization, egg concentration and incubation temperature were examined. Minimum sample size per treatment was also estimated. Exposure of oocytes for 10min to FSW alkalinized with NH4OH at pH 9.0, the use of undiluted sperm pre-activated during 45min and a concentration of 200 oocytesmL(-1), a gamete-contact time of 180min and egg incubation at 18°C during 24h at a concentration of 80 eggsmL(-1) were the conditions allowing maximal embryo-larval development success. With an error of 0.05, a sampling size ≥320 allows a 95% confidence in the estimate. This Patella spp. acute bioassay fulfills a number of important a priori requirements to be used in ecotoxicological studies. Nevertheless, in vitro fertilization requires considerable handling, which may lead to failure in fecundation. Such difficulties are also addressed, in order to facilitate the routine use of this protocol by other laboratories.

  19. Analysis of the secondary structure of mitochondrial LSU rRNA of Peruvian land snails (Orthalicidae: Gastropoda

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    Jorge Ramirez Ramirez

    2011-05-01

    Full Text Available The alignment of ribosomal genes is difficult due to insertion and deletion events of nucleotides, making the alignment ambiguous. This can be overcome by using information from the secondary structure of ribosomal genes. The aim of this study was to evaluate the utility of the secondary structure in improving the alignment of the 16S rRNA gene in land snails of the family Orthalicidae. We assessed 10 Orthalicid species (five genera. Total DNA was isolated and the partial 16S rRNA gene was amplified and sequenced using internal primers. The sequences were aligned with ClustalX and manually corrected, in DCSE format, using the 16S rRNA secondary structure of Albinaria caerulea (Pulmonata: Clausiliidae. The sequences obtained ranged from 323 to 345 bp corresponding to parts of both domains IV and V of the 16S rRNA gene. The secondary structure was recovered by homology using RnaViz 2.0. Most stems are conserved, and in general the loops are more variable. The compensatory mutations in stems are related to maintenance of the structure. The absence of a bulge-stem-loop in domain V places the family Orthalicidae within the Heterobranchia.

  20. Newly-discovered muscle in the larva of Patella coerulea (Mollusca, Gastropoda) suggests the presence of a larval extensor

    NARCIS (Netherlands)

    Damen, Peter; Dictus, Wim J.A.G.

    2002-01-01

    The development of the muscular system of the gastropod mollusc Patella has been thoroughly studied. As a result, two larval retractors, the main and accessory larval retractor, had been described in the larva of Patella. These muscles were supposed to be responsible for the retraction of the larval

  1. Simbiosis entre Collisella spp. (Gastropoda) y Zygantroplana ups (Platyhelminthes: Turbellaria) en el Golfo de California, México

    OpenAIRE

    González, Norma Emma; Sergio I. Salazar-Vallejo

    2015-01-01

    The flatworm Zygantroplana ups Marcus & Harry was originally described as a symbiont of the oyster Myrakeena angelica (Rochebrune) from Baja Califomia (BC), Mexico. Here it is recorded in association with several limpet species (Collisella spp.) in Bahía de la Paz, southem BC. The relationship is not species-specific, and there was no association bctween Iimpet body sire and the number of planarians, bu! larger limpets had a greater incidence rateo Si tes with higher limpet densities had lowe...

  2. Notes on Bulimulidae (Gastropoda, Euthyneura), 41) some Bulimulidea from French Guyana and Surinam, with notes on their Anatomy

    NARCIS (Netherlands)

    Breure, A.S.H.

    1976-01-01

    During work for a generic revision of the family Bulimulidae some material from French Guyana and Surinam came to my hands. This material stems from the collections of the Muséum National d'Histoire Naturelle, Paris (MNHN), the Rijksmuseum van Natuurlijke Historie, Leiden (RMNH) and the Zoölogisch M

  3. The sudden appearance of Aeolidiella glauca (Gastropoda: Opisthobranchia) in lake Greveliningen (S.W. Netherlands) in 1983 and 1984

    NARCIS (Netherlands)

    Dekker, R.

    1985-01-01

    In 1983 and 1984 a population of the nudibranch Aeolidiella glauca (Alder & Hancock, 1845) was found in the saline Lake Grevelingen (S.W. Netherlands). The number of specimens observed exceeds by far the total number previously recorded from the Dutch coast. Field observations on food intake suggest

  4. Sibynomorphus neuwiedi (Ihering, 1911 (Serpentes; Dipsadidae and Potamojanuarius lamellatus (Semper, 1885 (Gastropoda; Veronicellidae: a trophic relationship revealed

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    Thiago Maia-Carneiro

    2012-03-01

    Full Text Available The Dispsadidae serpents from the genus Sibynomorphus are restricted to South America and include twelve species currently known, which occur in Brazil, Argentina, Peru, and Ecuador. Sibynomorphus neuwiedi is a species endemic to forested areas of the Atlantic Rainforest biome, and it is specialized in eating gastropods. Eight adult individuals of S. neuwiedi were collected between April 1998 and June 2003 at the surroundings of the Vila dos Dois Rios village (23°11’S, 44°12’W, in the Parque Estadual da Ilha Grande, in the municipality of Angra dos Reis, state of Rio de Janeiro, Brazil. In the laboratory, we dissected their stomachs for analysis of its contents. We found prey in four of them (50%, all represented by the slug Potamojanuarius lamellatus (Veronicellidae, and four individuals had empty stomach. The consumption of slugs from the Family Veronicellidae by serpents from the tribe Dipsadini has been reported, nevertheless, we report the occurrence of P. lamellatus in the diet of S. neuwiedi for the first time.

  5. Impacts of Urbanization on the Biodiversity of the Imperiled Snail Fauna (Gastropoda: Prosobranchia: Pleuroceridae) of the Cahaba River, Alabama, USA.

    Science.gov (United States)

    Tolley-Jordan, L.; Huryn, A.

    2005-05-01

    The conservation of the Pleuroceridae is of concern in the Mobile River Basin (MRB) since 31 of 38 extinct gastropod species from this drainage are pleurocerids. The fauna of the Cahaba River, as a global hot-spot for pleurocerid diversity, is of particular concern. Its flow is not regulated by dams, so its fauna has not been affected by habitat alteration due to impoundment like other major MRB tributaries. Ongoing urbanization within its watershed, however, is expected to have consequences for its snail fauna. A 1993 survey documented 23 pleurocerid species among 109 sites in the drainage. Changes in land cover from 1992 to 2004 were quantified for 10 of these. Five sites showed a 13-36% increase in urban land-cover; five showed no change. Elimia cahawbensis, E. carinifera, E. carinocostata, E. clara and Pleurocera vestita occurred among these sites during 1993 (S= 0-4 spp./site). A comparison of species occurrence in 1992 and 2005 showed no change in S at 6 sites, while three lost 1 species, and one lost 3 species. Reductions in S were not correlated with changes in land cover, however. Factors not directly correlated with urbanization may thus be contributing to losses of snail diversity in the MRB.

  6. Identification of two carbonic anhydrases in the mantle of the European Abalone Haliotis tuberculata (Gastropoda, Haliotidae): phylogenetic implications.

    Science.gov (United States)

    LE Roy, Nathalie; Marie, Benjamin; Gaume, Béatrice; Guichard, Nathalie; Delgado, Sidney; Zanella-Cléon, Isabelle; Becchi, Michel; Auzoux-Bordenave, Stéphanie; Sire, Jean-Yves; Marin, Frédéric

    2012-07-01

    Carbonic anhydrases (CAs) represent a diversified family of metalloenzymes that reversibly catalyze the hydration of carbon dioxide. They are involved in a wide range of functions, among which is the formation of CaCO(3) skeletons in metazoans. In the shell-forming mantle tissues of mollusks, the location of the CA catalytic activity is elusive and gives birth to contradicting views. In the present paper, using the European abalone Haliotis tuberculata, a key model gastropod in biomineralization studies, we identified and characterized two CAs (htCA1 and htCA2) that are specific of the shell-forming mantle tissue. We analyzed them in a phylogenetic context. Combining various approaches, including proteomics, activity tests, and in silico analyses, we showed that htCA1 is secreted but is not incorporated in the organic matrix of the abalone shell and that htCA2 is transmembrane. Together with previous studies dealing with molluskan CAs, our findings suggest two possible modes of action for shell mineralization: the first mode applies to, for example, the bivalves Unio pictorum and Pinctada fucata, and involves a true CA activity in their shell matrix; the second mode corresponds to, for example, the European abalone, and does not include CA activity in the shell matrix. Our work provides new insight on the diversity of the extracellular macromolecular tools used for shell biomineralization study in mollusks.

  7. Annotated type catalogue of the Megaspiridae, Orthalicidae, and Simpulopsidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London.

    Science.gov (United States)

    Breure, Abraham S H; Ablett, Jonathan D

    2015-01-01

    The type status is described for 65 taxa of the Orthalicoidea, classified within the families Megaspiridae (14), Orthalicidae (30), and Simpulopsidae (20); one taxon is considered a nomen inquirendum. Lectotypes are designated for the following taxa: Helixbrephoides d'Orbigny, 1835; Simpulopsiscumingi Pfeiffer, 1861; Bulimulus (Protoglyptus) dejectus Fulton, 1907; Bulimusiris Pfeiffer, 1853. The type status of Bulimussalteri Sowerby III, 1890, and Strophocheilus (Eurytus) subirroratus da Costa, 1898 is now changed to lectotype according Art. 74.6 ICZN. The taxa Bulimusloxostomus Pfeiffer, 1853, Bulimusmarmatensis Pfeiffer, 1855, Bulimusmeobambensis Pfeiffer, 1855, and Orthalicuspowissianusvar.niveusPreston 1909 are now figured for the first time. The following taxa are now considered junior subjective synonyms: Bulimusmarmatensis Pfeiffer, 1855 = Helix (Cochlogena) citrinovitrea Moricand, 1836; Vermiculatus Breure, 1978 = Bocourtia Rochebrune, 1882. New combinations are: Kuschelenia (Bocourtia) Rochebrune, 1882; Kuschelenia (Bocourtia) aequatoria (Pfeiffer, 1853); Kuschelenia (Bocourtia) anthisanensis (Pfeiffer, 1853); Kuschelenia (Bocourtia) aquila (Reeve, 1848); Kuschelenia (Bocourtia) badia (Sowerby I, 1835); Kuschelenia (Bocourtia) bicolor (Sowerby I, 1835); Kuschelenia (Bocourtia) caliginosa (Reeve, 1849); Kuschelenia (Bocourtia) coagulata (Reeve, 1849); Kuschelenia (Bocourtia) cotopaxiensis (Pfeiffer, 1853); Kuschelenia (Bocourtia) filaris (Pfeiffer, 1853); Karaindentata (da Costa, 1901); Clathrorthalicusmagnificus (Pfeiffer, 1848); Simpulopsis (Eudioptus) marmartensis (Pfeiffer, 1855); Kuschelenia (Bocourtia) nucina (Reeve, 1850); Kuschelenia (Bocourtia) ochracea (Morelet, 1863); Kuschelenia (Bocourtia) peaki (Breure, 1978); Kuschelenia (Bocourtia) petiti (Pfeiffer, 1846); Clathrorthalicusphoebus (Pfeiffer, 1863); Kuschelenia (Bocourtia) polymorpha (d'Orbigny, 1835); Scholvieniaporphyria (Pfeiffer, 1847); Kuschelenia (Bocourtia) purpurata (Reeve, 1849); Kuschelenia (Bocourtia) quechuarum Crawford, 1939; Quechuasalteri (Sowerby III, 1890); Kuschelenia (Bocourtia) subfasciata Pfeiffer, 1853; Clathrorthalicusvictor (Pfeiffer, 1854). In an addedum a lectotype is being designated for Bulimulus (Drymaeus) interruptusvar.pallidus Preston, 1909. An index is included to all taxa mentioned in this paper and the preceding ones in this series (Breure and Ablett 2011, 2012, 2014).

  8. Annotated type catalogue of Bothriembryon (Mollusca, Gastropoda, Orthalicoidea) in Australian museums, with a compilation of types in other museums.

    Science.gov (United States)

    Breure, Abraham S H; Whisson, Corey S

    2012-01-01

    Type material of 41 Australian Bothriembryon taxa present in Australian museums is critically listed, indicating systematic issues that need to be resolved in further studies. Information on additional type material of 22 taxa in non-Australian museums is compiled. The seven fossil taxa known so far are included in this catalogue. Based on the current systematic position, 38 species are treated in this paper. Bothriembryon jacksoni Iredale, 1939, Bothriembryon notatus Iredale, 1939, Bothriembryon praecelsus Iredale, 1939 and Bothriembryon serpentinus Iredale, 1939 are elevated to species level. Bothriembryon gratwicki (Cox, 1899) is listed as status to be determined.

  9. Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda) in the Museum für Naturkunde, Berlin.

    Science.gov (United States)

    Breure, Abraham S H

    2013-01-01

    The type status is described of 96 taxa classified within the superfamily Orthalicoidea and present in the Mollusca collection of the Museum für Naturkunde der Humboldt-Universität zu Berlin. Lectotypes are designated for the following taxa: Orthalicus elegans Rolle, 1895; Bulimus maranhonensis Albers, 1854; Orthalicus nobilis Rolle, 1895; Orthalichus tricinctus Martens, 1893. Orthalicus sphinx tresmariae is introduced as new name for Zebra sphinx turrita Strebel, 1909, not Zebra quagga turrita Strebel, 1909. The following synonyms are established: Zebra crosseifischeri Strebel, 1909 = Orthalicus princeps fischeri Martens, 1893; Orthalicus isabellinus Martens, 1873 = Orthalicus bensoni (Reeve, 1849); Zebra zoniferus naesiotes Strebel, 1909 = Orthalicus undatus (Bruguière, 1789); Porphyrobaphe (Myiorthalicus) dennisoni pallida Strebel, 1909 = Hemibulimus dennisoni (Reeve, 1848); Zebra delphinus pumilio Strebel, 1909 = Orthalicus delphinus (Strebel, 1909); Orthalicus (Laeorthalicus) reginaeformis Strebel, 1909 = Corona perversa (Swainson, 1821); Bulimus (Eurytus) corticosus Sowerby III, 1895 = Plekocheilus (Eurytus) stuebeli Martens, 1885. The taxon Bulimus (Eudioptus) psidii Martens, 1877 is now placed within the family Sagdidae, tentatively in the genus Platysuccinea. Appendices are included with an index to all the types of Orthalicoidea extant (including those listed by Köhler 2007) and a partial list of letters present in the correspondence archives.

  10. Annotated type catalogue of the Bothriembryontidae and Odontostomidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London.

    Science.gov (United States)

    Breure, Abraham S H; Ablett, Jonathan D

    2012-01-01

    The type status is described for specimens of 84 taxa classified within the families Bothriembryontidae and Odontostomidae (superfamily Orthalicoidea) and kept in the Natural History Museum, London. Lectotypes are designated for Bulimus (Liparus) brazieri Angas, 1871; Bulimus broderipii Sowerby I, 1832; Bulimus fuligineus Pfeiffer, 1853; Helix guarani d'Orbigny, 1835; Bulimus (Tomigerus) ramagei E.A. Smith, 1890; Helix rhodinostoma d'Orbigny, 1835; Bulimus (Bulimulus) ridleyi E.A. Smith, 1890. The type status of the following taxa is changed to lectotype in accordance with Art. 74.6 ICZN: Placostylus (Euplacostylus) cylindricus Fulton, 1907; Bulimus pyrostomus Pfeiffer, 1860; Bulimus turneri Pfeiffer, 1860. The following taxon is synonymised: Bulimus oblitus Reeve, 1848 = Bahiensis neglectus (Pfeiffer, 1847).

  11. Drusia (Escutiella alexantoni n. sp. (Gastropoda, Pulmonata, Parmacellidae, a new terrestrial slug from the Atlantic coast of Morocco

    Directory of Open Access Journals (Sweden)

    Martínez–Ortí, A.

    2013-06-01

    Full Text Available We describe a new parmacellid, Drusia (Escutiella alexantoni n. sp. from the Moroccan Atlantic coast. The species most closely related to the new taxon are D. (E. deshayesii and D. (D. valenciennii. The new parmacellid differs from D. (E deshayesii mainly by the presence of external spots and bands on both the back and the shield, a reproductive system with uneven atrial appendices of the horn–shaped organ, and a different reticulated pattern of the inner epiphallus. It differs from D. (D. valenciennii mainly for the appearance of the shell and the pattern and disposition of the bumps inside the penis, the presence of an elbow–shape in this organ, and the reticulated appearance of the inner wall of the epiphallus. An updated dichotomous key of the family Parmacellidae is provided.

  12. Ultrastructure and Glycoconjugate Pattern of the Foot Epithelium of the Abalone Haliotis tuberculata (Linnaeus, 1758 (Gastropoda, Haliotidae

    Directory of Open Access Journals (Sweden)

    I. Bravo Portela

    2012-01-01

    Full Text Available The foot epithelium of the gastropod Haliotis tuberculata is studied by light and electron microscopy in order to contribute to the understanding of the anatomy and functional morphology of the mollusks integument. Study of the external surface by scanning electron microscopy reveals that the side foot epithelium is characterized by a microvillus border with a very scant presence of small ciliary tufts, but the sole foot epithelium bears a dense field of long cilia. Ultrastructural examination by transmission electron microscopy of the side epithelial cells shows deeply pigmented cells with high electron-dense granular content which are not observed in the epithelial sole cells. Along the pedal epithelium, seven types of secretory cells are present; furthermore, two types of subepithelial glands are located just in the sole foot. The presence and composition of glycoconjugates in the secretory cells and subepithelial glands are analyzed by conventional and lectin histochemistry. Subepithelial glands contain mainly N-glycoproteins rich in fucose and mannose whereas secretory cells present mostly acidic sulphated glycoconjugates such as glycosaminoglycans and mucins, which are rich in galactose, N-acetyl-galactosamine, and N-acetyl-glucosamine. No sialic acid is present in the foot epithelium.

  13. Revision of the genus Turris Batsch, 1789 (Gastropoda: Conoidea: Turridae) with the description of six new species

    Science.gov (United States)

    Kilburn, Richard N.; Fedosov, Alexander E.; Olivera, Baldomero M.

    2012-01-01

    The taxonomy of the genus Turris Batsch, 1789, type genus of the family Turridae, widespread in shallow-water habitats of tropic Indo-Pacific, is revised. A total of 31 species of Turris, are here recognized as valid. New species described: Turris chaldaea, Turris clausifossata, Turris guidopoppei, Turris intercancellata, Turris kantori, T. kathiewayae. Homonym renamed: Turris bipartita nom. nov. for Pleurotoma variegata Kiener, 1839 (non Philippi, 1836). New synonymies: Turris ankaramanyensis Bozzetti, 2006 = Turris tanyspira Kilburn, 1975; Turris imperfecti, T. nobilis, T. pulchra and T. tornatum Röding, 1798, and Turris assyria Olivera, Seronay & Fedosov, 2010 = T. babylonia; Turris dollyi Olivera, 2000 = Pleurotoma crispa Lamarck, 1816; Turris totiphyllis Olivera, 2000 = Turris hidalgoi Vera-Peláez, Vega-Luz & Lozano-Francisco, 2000; Turris kilburni Vera-Peláez, Vega-Luz & Lozano-Francisco, 2000 = Turris pagasa Olivera, 2000; Turris (Annulaturris) munizi Vera-Peláez, Vega-Luz & Lozano-Francisco, 2000 = Gemmula lululimi Olivera, 2000. Revised status: Turris intricata Powell, 1964, Pleurotoma variegata Kiener, 1839 (non Philippi, 1836) and Pleurotoma yeddoensis Jousseaume, 1883, are regarded as full species (not subspecies of Turris crispa). Neotype designated: For Pleurotoma garnonsii Reeve, 1843, to distinguish it from Turris garnonsii of recent authors, type locality emended to Zanzibar. New combination: Turris orthopleura Kilburn, 1983, is transferred to genus Makiyamaia, family Clavatulidae. PMID:23847408

  14. A new species of Haplosporidium Caullery & Mesnil, 1899 in the marine false limpet Siphonaria lessonii (Gastropoda: Siphonariidae) from Patagonia.

    Science.gov (United States)

    Ituarte, Cristián; Bagnato, Estefanía; Siddall, Mark; Cremonte, Florencia

    2014-05-01

    A new species of Haplosporidium Caullery & Mesnil, 1899 parasitising the pulmonate gastropod Siphonaria lessonii Blainville in Patagonia, Argentina, is described based on morphological (scanning and transmission electron microscopy) and sequence (small subunit ribosomal RNA gene) data. Different stages of sporulation were observed as infections disseminated in the digestive gland. Haplosporidium patagon n. sp. is characterised by oval or slightly subquadrate spores with an operculum that is ornamented with numerous short digitiform projections of regular height, perpendicular to and covering its outer surface. The operculum diameter is slightly larger than the apical diameter of the spore. Neither the immature nor mature spores showed any kind of projections of the exosporoplasm or of the spore wall. Regarding phylogenetic affinities, the new species was recovered as sister to an undescribed species of Haplosporidium Caullery & Mesnil, 1899 from the polychaete family Syllidae Grube from Japanese waters. The morphological characters (ornamentation of the operculum, spore wall structure, shape and size of spores, and the lack of spore wall projections) corroborate it as an as yet undescribed species of Haplosporidium and the first for the phylum in marine gastropods of South America. Siphonaria lessonii is the only known host to date.

  15. The Japanese oyster drill Ocinebrellus inornatus (Récluz, 1851) (Mollusca, Gastropoda, Muricidae), introduced to the Limfjord, Denmark

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Faasse, Marco; Gittenberger, Adriaan

    2012-01-01

    The predatory neogastropod Ocinebrellus inornatus was first reported from Europe in W France in 1995 and has since been detected at other sites in NW and N France and The Netherlands. It is native to the North Pacific where it preys on the Pacific oyster Crassostrea gigas. Here we report on the o...

  16. Observations on the breeding habits, shell development, decollation, and reproductive anatomy of Pontophaedusa funiculum (Mousson 1856 (Gastropoda, Pulmonata, Clausiliidae, Phaedusinae

    Directory of Open Access Journals (Sweden)

    Barna Páll-Gergely

    2008-02-01

    Full Text Available The internal and external egg morphology, shell development, decollation process, mating behaviour and reproductive anatomy (genital structure, inner structure of the penis, fine structure of the retractor muscle and the spermatophore of the clausiliid Pontophaedusa funiculum (Mousson 1856 are described, and illustrated by photographs of the laid eggs, their inner structure, juvenile, young adult and old individuals, as well as a schematic drawing of the mating. P. funiculum is the only known clausiliid species with hard shelled eggs and the only known example of the family Clausiliidae which mates face to face. The taxonomic position within the Phaedusinae subfamily is mentioned.

  17. Histology and Cytochemistry of the Neurosecretory Cells (NSC of the Freshwater Snail Lymnaea luteola (Lamarck Mollusca: Gastropoda

    Directory of Open Access Journals (Sweden)

    Vijaya Kumar Kanapala

    2015-01-01

    Full Text Available Four types of neurosecretory (NS cells are noticed in the cerebral, pleural, buccal and pedal ganglion of the freshwater snail Lymnaea luteola. According to the size and staining properties they are classified as A, B, C and D type cells. These are giant cells, medium cells, small cells and smallest cells. Type ‘A’ cells are largest of the all cells and measures about 0.0600-0.0800 mm in diameter. The B cells are smaller than ‘A’ cells and are ranges from 0.035-0.040 mm in diameter. The ‘C’ and ‘D’ cells are smaller than the ‘A’ and ‘B ‘cells and more or less oval in shape. The histochemical observations reveal that the neurosecretory material is rich in carbohydrates, disulphides, sulfhydryl group, protein bound amino groups, glycoprotein and lipids.

  18. Mitochondrial and nuclear DNA analysis revealed a cryptic species and genetic introgression in Littorina sitkana (Mollusca, Gastropoda).

    Science.gov (United States)

    Azuma, Noriko; Yamazaki, Tomoyasu; Chiba, Susumu

    2011-12-01

    We investigated mitochondrial and nuclear DNA genotypes in nominal Littorina sitkana samples from 2 localities in Eastern Hokkaido, northern Japan. Our results indicated the existence of cryptic species. In the analysis of partial mitochondrial Cytchrome b gene sequences, haplotypes of L. sitkana samples were monophyletic in a phylogenetic tree with orthologous sequences from other Littorina species, but were apparently separated in 2 clades. One included typical L. sitkana (CBa clade) samples, which formed a clade with an allopatric species, L. horikawai. The other, CBb, was independent from CBa and L. horikawai. Haplotypes of the mitochondrial 16S rRNA gene also separated into 2 clades. We additionally examined intron sequence of the heat shock cognate 70 (HSC70) nuclear gene and identified 17 haplotypes. These were also separated into 2 clades, HSCa and HSCb. Among the examined Hokkaido samples, 60% of individuals were heterozygotes. However, each heterozygote consisted of haplotypes from the same clade, HSCa or HSCb, and no admixture of HSCa and HSCb haplotypes was observed. These results indicate reproductive isolation between the 2 clades. Among the genotyped Hokkaido samples, 93% of individuals had CBa + HSCa or CBb + HSCb genotypes, and 7% had CBb + HSCa genotypes. The discrepancy between the mtDNA and nuclear DNA haplotypes in a few individuals may have been caused by genetic introgression due to past hybridization.

  19. [Combined effect of environmental temperature and trematodes on fatty acids composition of lipids of Littorina saxatilis (Olivi 1792) (Gastropoda, Prosobranchia)].

    Science.gov (United States)

    Arakelova, E S; Chebotareva, M A; Zabelinskiĭ, S A

    2004-01-01

    An effect of environmental temperatures and invasion by helminthes larvae on fatty acids composition of digestive gland lipids of marine littoral gastropod Littorina saxatilis from White Sea and Barents Sea was investigated. We have compared gastropods from boreal and subarctic populations. It was found that gastropods from waters of lower temperature have increased omega3/omega6 fatty acids ratio. However, saturation index of individual membrane phospholipids was not affected. Also, content of eicosenoic acid (20:1) in individual phospholipids was not affected by temperature. Invasion increases the omega3/omega6 ratio of common lipids but not the omega3/omega6 ratio of common and individual phospholipids with the exception of phosphatidilcholine of cold water mollusks from Barents Sea that had this ratio doubled. In contrast to temperature, invasion affects the content of eicosenoic acid that was increased in the investigated organs. Adaptability of these effects is discussed regarding parasite-host system.

  20. Heat production in Littorina saxatilis Olivi and Littorina neritoides L. (gastropoda: Prosobranchia) during an experimental exposure to air

    Science.gov (United States)

    Kronberg, Inge

    1990-06-01

    The adaptation of littorinid molluscs to prolonged aerial exposure was investigated by the determination of heat production. Littorina saxatilis, inhabiting the upper eulittoral, reached a maximum metabolic activity during submersion (heat production: 3.26×10-3J s-1 (gadw)-1. On the first three days of desiccation, the heat production was continuously reduced to 40% of the submersed value. A prolonged aerial exposure was lethal for this species. In the supralittoral L. neritoides, three stages of energy metabolism could be observed: An intermediate heat production during submersion (1.97×10-3Js-1 (gadw)-1), an increased metabolism during the first hour of aerial exposure (heat production 204% of submersed value), and a minimal metabolism (39% of the submersed value and 19% of maximum value) during the following days and weeks of desiccation. Recovery depended on water salinity; L. saxatilis proved to be less euryhaline than L. neritoides. Thus, the metabolic adaptations correlate with the level of littoral habitat; inactivity combined with a drastically reduced energy consumption is a metabolically economic way to survive in periodically dry environments.

  1. Annotated type catalogue of the Bulimulidae (Mollusca, Gastropoda, Orthalicoidea in the Natural History Museum, London

    Directory of Open Access Journals (Sweden)

    Abraham Breure

    2014-03-01

    Full Text Available The type status is described of 404 taxa classified within the family Bulimulidae (superfamily Orthalicoidea and kept in the London museum. Lectotypes are designated for Bulimus aurifluus Pfeiffer, 1857; Otostomus bartletti H. Adams, 1867; Helix cactorum d’Orbigny, 1835; Bulimus caliginosus Reeve, 1849; Bulimus chemnitzioides Forbes, 1850; Bulimus cinereus Reeve, 1849; Helix cora d’Orbigny, 1835; Bulimus fallax Pfeiffer, 1853; Bulimus felix Pfeiffer, 1862; Bulimus fontainii d’Orbigny, 1838; Bulimus fourmiersi d’Orbigny, 1837; Bulimus (Mesembrinus gealei H. Adams, 1867; Bulimus gruneri Pfeiffer, 1846; Bulimus humboldtii Reeve, 1849; Helix hygrohylaea d’Orbigny, 1835; Bulimus jussieui Pfeiffer, 1846; Bulimulus (Drymaeus binominis lascellianus E.A. Smith, 1895; Helix lichnorum d’Orbigny, 1835; Bulimulus (Drymaeus lucidus da Costa, 1898; Bulimus luridus Pfeiffer, 1863; Bulimus meleagris Pfeiffer, 1853; Bulimus monachus Pfeiffer, 1857; Bulimus montagnei d’Orbigny, 1837; Helix montivaga d’Orbigny, 1835; Bulimus muliebris Reeve, 1849; Bulimus nigrofasciatus Pfeiffer in Philippi 1846; Bulimus nitelinus Reeve, 1849; Helix oreades d’Orbigny, 1835; Helix polymorpha d’Orbigny, 1835; Bulimus praetextus Reeve, 1849; Bulinus proteus Broderip, 1832; Bulimus rusticellus Morelet, 1860; Helix sporadica d’Orbigny, 1835; Bulimus sulphureus Pfeiffer, 1857; Helix thamnoica var. marmorata d’Orbigny, 1835; Bulinus translucens Broderip in Broderip and Sowerby I 1832; Helix trichoda d’Orbigny, 1835; Bulinus ustulatus Sowerby I, 1833; Bulimus voithianus Pfeiffer, 1847; Bulimus yungasensis d’Orbigny, 1837.The type status of the following taxa is changed to lectotype in accordance with Art. 74.6 ICZN: Bulimulus (Drymaeus caucaensis da Costa, 1898; Drymaeus exoticus da Costa, 1901; Bulimulus (Drymaeus hidalgoi da Costa, 1898; Bulimulus (Drymaeus interruptus Preston, 1909; Bulimulus (Drymaeus inusitatus Fulton, 1900; Bulimulus latecolumellaris Preston, 1909; Bulimus (Otostomus napo Angas, 1878; Drymaeus notabilis da Costa, 1906; Drymaeus notatus da Costa, 1906; Bulimulus (Drymaeus nubilus Preston, 1903; Drymaeus obliquistriatus da Costa, 1901; Bulimus (Drymaeus ochrocheilus E.A. Smith, 1877; Bulimus (Drymaeus orthostoma E.A. Smith, 1877; Drymaeus expansus perenensis da Costa, 1901; Bulimulus pergracilis Rolle, 1904; Bulimulus (Drymaeus plicatoliratus da Costa, 1898; Drymaeus prestoni da Costa, 1906; Drymaeus punctatus da Costa, 1907; Bulimus (Leptomerus sanctaeluciae E.A. Smith, 1889; Bulimulus (Drymaeus selli Preston, 1909; Drymaeus subventricosus da Costa, 1901; Bulimulus ( Drymaeus tigrinus da Costa, 1898; Drymaeus volsus Fulton, 1907; Drymaeus wintlei Finch, 1929; Bulimus zhorquinensis Angas, 1879; Bulimulus (Drymaeus ziczac da Costa, 1898.The following junior subjective synonyms are established: Bulimus antioquensis Pfeiffer, 1855 = Bulimus baranguillanus Pfeiffer, 1853; Drymaeus bellus da Costa, 1906 = Drymaeus blandi Pilsbry, 1897; Bulimus hachensis Reeve 1850 = Bulimus gruneri Pfeiffer, 1846 = Bulimus columbianus Lea, 1838; Bulimus (Otostomus lamas Higgins 1868 = Bulimus trujillensis Philippi, 1867; Bulimulus (Drymaeus binominis lascellianus E.A. Smith, 1895 = Bulimulus (Drymaeus binominis E.A. Smith, 1895; Drymaeus multispira da Costa, 1904 = Helix torallyi d’Orbigny, 1835; Bulimulus (Drymaeus plicatoliratus Da Costa, 1898 = Bulimus convexus Pfeiffer, 1855; Bulimus sugillatus Pfeiffer, 1857 = Bulimus rivasii d’Orbigny, 1837; Bulimus meridionalis Reeve 1848 [June] = Bulimus voithianus Pfeiffer, 1847.New combinations are: Bostryx montagnei (d’Orbigny, 1837; Bostryx obliquiportus (da Costa, 1901; Bulimulus heloicus (d’Orbigny, 1835; Drymaeus (Drymaeus lusorius (Pfeiffer, 1855; Drymaeus (Drymaeus trigonostomus (Jonas, 1844; Drymaeus (Drymaeus wintlei Finch, 1929; Drymaeus (Mesembrinus conicus da Costa, 1907; Kuschelenia (Kuschelenia culminea culminea (d’Orbigny, 1835; Kuschelenia (K. culmineus edwardsi (Morelet, 1863; Kuschelenia (K. gayi (Pfeiffer, 1857; Kuschelenia (K. tupacii (d’Orbigny, 1835; Kuschelenia (Vermiculatus anthisanensis (Pfeiffer, 1853; Kuschelenia (Vermiculatus aquilus (Reeve, 1848; Kuschelenia (Vermiculatus bicolor (Sowerby I, 1835; Kuschelenia (Vermiculatus caliginosus (Reeve, 1849; Kuschelenia (Vermiculatus cotopaxiensis (Pfeiffer, 1853; Kuschelenia (Vermiculatus filaris (Pfeiffer, 1853; Kuschelenia (Vermiculatus ochracea (Morelet, 1863; Kuschelenia (Vermiculatus petiti (Pfeiffer, 1846; Kuschelenia (Vermiculatus purpuratus (Reeve, 1849; Kuschelenia (Vermiculatus quechuarum (Crawford, 1939; Naesiotus cinereus (Reeve, 1849; Naesiotus dentritis (Morelet, 1863; Naesiotus fontainii (d’Orbigny, 1838; Naesiotus orbignyi (Pfeiffer, 1846; Protoglyptus pilosus (Guppy, 1871; Protoglyptus sanctaeluciae (E.A. Smith, 1889.Type material of the following taxa is figured herein for the first time: Bulimus cinereus Reeve, 1849; Bulimus coriaceus Pfeiffer, 1857; Bulimulus laxostylus Rolle, 1904; Bulimus pliculatus Pfeiffer, 1857; Bulimus simpliculus Pfeiffer, 1855.

  2. Taxonomic study on the family Mitridae (Mollusca: Gastropoda: Neogastropoda) from the China's seas. Subfamilies: Imbricariinae and Cylindromitrinae

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Ninteen species of subfamilies Imbricariinae and Cylindromitrinae, family Mitridae, are recorded from the China's seas. Of which, one genus and six species are recorded for the first time from China' s seas, i.e., genus Ziba Adams H and Adams A, Cancilla (Cancilla)carnicolor, Ziba duplilirata, Z. insculpta, Neocancilla circula, Scabricola (Scabricola) desetangsii, Scabricola (Swainsonia) ocellata ocellata.

  3. Myogenesis in Aplysia californica (Cooper, 1863) (Mollusca, Gastropoda, Opisthobranchia) with special focus on muscular remodeling during metamorphosis.

    Science.gov (United States)

    Wollesen, Tim; Wanninger, Andreas; Klussmann-Kolb, Annette

    2008-07-01

    To date only few comparative approaches tried to reconstruct the ontogeny of the musculature in invertebrates. This may be due to the difficulties involved in reconstructing three dimensionally arranged muscle systems by means of classical histological techniques combined with light or transmission electron microscopy. Within the scope of the present study we investigated the myogenesis of premetamorphic, metamorphic, and juvenile developmental stages of the anaspidean opisthobranch Aplysia californica using fluorescence F-actin-labeling in conjunction with modern confocal laser scanning microscopy. We categorized muscles with respect to their differentiation and degeneration and found three true larval muscles that differentiate during the embryonic and veliger phase and degenerate during or slightly after metamorphosis. These are the larval retractor, the accessory larval retractor, and the metapodial retractor muscle. While the pedal retractor muscle, some transversal mantle fibers and major portions of the cephalopedal musculature are continued and elaborated during juvenile and adult life, the buccal musculature and the anterior retractor muscle constitute juvenile/adult muscles which differentiate during or after metamorphosis. The metapodial retractor muscle has never been reported for any other gastropod taxon. Our findings indicate that the late veliger larva of A. californica shares some common traits with veligers of other gastropods, such as a larval retractor muscle. However, the postmetamorphic stages exhibit only few congruencies with other gastropod taxa investigated to date, which is probably due to common larval but different adult life styles within gastropods. Accordingly, this study provides further evidence for morphological plasticity in gastropod myogenesis and stresses the importance of ontogenetic approaches to understand adult conditions and life history patterns.

  4. Radix dolgini: The integrative taxonomic approach supports the species status of a Siberian endemic snail (Mollusca, Gastropoda, Lymnaeidae).

    Science.gov (United States)

    Vinarski, Maxim V; Aksenova, Olga V; Bespalaya, Yulia V; Bolotov, Ivan N; Schniebs, Katrin; Gofarov, Mikhail Yu; Kondakov, Alexander V

    2016-01-01

    The molecular techniques are the standard tool for the study of the taxonomic position and phylogenetic affinities of the lymnaeid genus Radix Montfort, 1810, and the majority of the European representatives of this taxon have been studied in this respect. However, a plethora of nominal species of Radix described from Northern Asia (Siberia and the Russian Far East) are still characterized only morphologically, raising some doubts concerning their validity. In this paper, we present the triple (morphological, molecular, and zoogeographical) evidence that there is at least one endemic species of Radix, Radix dolgini (Gundrizer and Starobogatov, 1979), widely distributed in Siberia and Western Mongolia. Phylogenetically, it is a sister species to the European R. labiata (Rossmaessler, 1835) [=R. peregra auct.], and their common ancestor most probably lived in the Pliocene, nearly 3.25Myr ago. Our results assume the existence of an extended dispersal barrier for freshwater hydrobionts between Europe and Siberia in the Late Pliocene that may be important for biogeographical explanations. Three other nominal Siberian species of Radix: R. kurejkae (Gundrizer and Starobogatov, 1979), R. gundrizeri (Kruglov and Starobogatov, 1983), and R. ulaganica (Kruglov and Starobogatov, 1983) proved to be the junior synonyms of R. dolgini.

  5. Spatial diversity of rocky midlittoral macro-invertebrates associated with the endangered species Patella ferruginea (Mollusca: Gastropoda) of Tunisian coastline

    Science.gov (United States)

    Tlig-Zouari, Sabiha; Rabaoui, Lotfi; Fguiri, Hosni; Diawara, Moctar; Ben Hassine, Oum Kalthoum

    2010-04-01

    The present study focuses on horizontal spatial variability of benthic macrofauna associated with Patella ferruginea. Thirty-six samples collected at 12 transects belonging to 4 midlittoral sites along the rocky Tunisian coastline, were examined. A total of 44 species belonging to 5 taxa were found. Multivariate analysis applied on gathered data did not show a horizontal spatial variability at small scale (between transects), but at large scale, between sites as well as sectors. Thus, three groups of communities were identified (GI: Korbous and El Haouaria; GIIa: Zembra Island and GIIb: Kelibia). The distribution of species abundance within these groups revealed that crustaceans were the most abundant taxon, due to the overwhelming dominance of Chthamalus stellatus. This substratum appeared to create favourable micro-habitats for the installation of molluscs including gastropods. Regarding the low diversity index ( H') and evenness ( J), they seemed to reflect a disturbance and a demographic unbalance within these communities. The heterogeneity of substrate surface, created by C. stellatus specimens appeared to be caused by various complex interactions established between the key components of these communities in particular suspension feeders, predators, herbivorous molluscs and macroalgae. Thus, the dynamic status of each of these communities is the result of these complex interactions.

  6. Recent expansion and relic survival: Phylogeography of the land snail genus Helix (Mollusca, Gastropoda) from south to north Europe.

    Science.gov (United States)

    Fiorentino, V; Manganelli, G; Giusti, F; Ketmaier, V

    2016-05-01

    Little is known about the evolutionary history of Helix, despite the fact that it includes the largest land snails in the western Palaearctic, some of which (e.g. H. pomatia Linnaeus, 1758) are valuable human food. We compared two groups of Helix with apparently contrasting evolutionary histories: the widespread species H. pomatia and the group distributed along the Italian Apennine chain, a relatively unknown set of species with a restricted distribution over a range of altitudes. To reconstruct the evolutionary trajectories of these two groups, we analysed morphological (shell and genitalia) and molecular characters (mitochondrial and nuclear markers) in a total of 59 populations from northern and central Europe (H. pomatia) and along the Apennine chain (various species). We also reconstructed the phylogeny and the evolutionary history of the genus by combining our data with that currently available in the literature. We found that spatial changes did not merely imply fragmentation of populations, but also implied environmental changes (woodlands vs. grasslands) that may have triggered the observed phenotypic diversification. We also found that Anatolia is the ancestral range of Helix and is therefore an important area for the Palaearctic diversity. The results provide insights into the evolutionary history of species richness and more generally into the processes that may have shaped the distribution and diversification of these organisms across Europe and the peri-Mediterranean area.

  7. Beiträge zur Kenntnis der Pupillacea. X. Eine Chondrula der Untergattung Eubrephulus auf dem Peloponnes (Mollusca: Gastropoda: Enidae)

    NARCIS (Netherlands)

    Gittenberger, E.

    1984-01-01

    A new Chondrula species is described, most probably belonging to the subgenus Eubrephulus, viz. Chondrula (Eubrephulus) peloponnesica spec. nov. The species is known from a single locality only, situated on the SE. Peloponnesus, Greece. Shells of the other two Eubrephulus species known are figured f

  8. Genetic structure of Onchidium "struma" (Mollusca: Gastropoda: Eupulmonata) from the coastal area of China based on mtCO I.

    Science.gov (United States)

    Zhou, Na; Shen, Heding; Chen, Cheng; Sun, Bianna; Zheng, Pei; Wang, Chengnuan

    2016-01-01

    The genetic diversity and population genetic structure of Onchidium "struma" were investigated using mitochondrial cytochrome c oxidase subunit I (CO I) gene sequences. A total of 240 individuals representing 10 collection sites from across a large portion of its known range were included in the analysis. Overall, 42 haplotypes were defined and 97 polymorphic sites were observed. The O. "struma" populations had high haplotype diversity (0.9280) and nucleotide diversity (0.0404). We inferred that the early maturity and extensive survival habitat led to high genetic diversity of O. "struma" populations in China. Bayesian analysis and SAMOVA analysis showed significant genetic differentiation among populations and all populations were divided into two groups, (HK and HN) versus (GY, DF, CX, CN, ND and XM). The Mantel test revealed no significant correlation between geographic distance and genetic distance (r = 0.251; p = 0.058). Restricted gene flow caused by a shorter term pelagic veliger stage and limited dispersal potential were inferred to result in genetic differentiation among populations based on nested analysis. HK population might be an invasive species by artificial transplantation.

  9. Limitations of cytochrome oxidase I for the barcoding of Neritidae (Mollusca: Gastropoda) as revealed by Bayesian analysis.

    Science.gov (United States)

    Chee, S Y

    2015-05-25

    The mitochondrial DNA (mtDNA) cytochrome oxidase I (COI) gene has been universally and successfully utilized as a barcoding gene, mainly because it can be amplified easily, applied across a wide range of taxa, and results can be obtained cheaply and quickly. However, in rare cases, the gene can fail to distinguish between species, particularly when exposed to highly sensitive methods of data analysis, such as the Bayesian method, or when taxa have undergone introgressive hybridization, over-splitting, or incomplete lineage sorting. Such cases require the use of alternative markers, and nuclear DNA markers are commonly used. In this study, a dendrogram produced by Bayesian analysis of an mtDNA COI dataset was compared with that of a nuclear DNA ATPS-α dataset, in order to evaluate the efficiency of COI in barcoding Malaysian nerites (Neritidae). In the COI dendrogram, most of the species were in individual clusters, except for two species: Nerita chamaeleon and N. histrio. These two species were placed in the same subcluster, whereas in the ATPS-α dendrogram they were in their own subclusters. Analysis of the ATPS-α gene also placed the two genera of nerites (Nerita and Neritina) in separate clusters, whereas COI gene analysis placed both genera in the same cluster. Therefore, in the case of the Neritidae, the ATPS-α gene is a better barcoding gene than the COI gene.

  10. Replacement names and nomenclatural comments for problematic species-group names in Europe's Neogene freshwater Gastropoda. Part 2

    Directory of Open Access Journals (Sweden)

    Thomas Neubauer

    2014-07-01

    Full Text Available In the course of a new database project on Miocene to Recent freshwater gastropods of Europe, a great many of primary and secondary homonyms were revealed. Such nomenclatural issues need clarification in order to avoid misunderstandings and wrong statements about geographical distributions and temporal ranges. The following 16 new names are introduced to replace existing homonyms: Theodoxus militaris jurisicpolsakae nom. n., Viviparus stevanovici nom. n., Melanopsis haueri ripanjensis nom. n., Melanopsis wolfgangfischeri nom. n., Micromelania ramacanensis nom. n., Pseudamnicola welterschultesi nom. n., Muellerpalia haszprunari nom. n., Muellerpalia pseudovalvatoides nom. n., Lithoglyphus gozhiki nom. n., Valvata heidemariae willmanni nom. n., Radix macaleti nom. n., Gyraulus okrugljakensis nom. n., Gyraulus rasseri nom. n., Gyraulus vrapceanus nom. n., Planorbarius halavatsi nom. n., and Segmentina mosbachensis nom. n. Additionally, six cases of homonyms are discussed that are not replaced by new names, because they are considered junior synonyms.

  11. Seasonal bioconcentration of heavy metals in Onchidium struma (Gastropoda: Pulmonata) from Chongming Island, the YangtzeEstuary, China

    Institute of Scientific and Technical Information of China (English)

    LI Xiaobo; JIA Linzhi; ZHAO Yunlong; WANG Qun; CHENG Yongxu

    2009-01-01

    The seasonal concentration changes of selected heavy metal Cd, Cr, Cu, Fe, Mn, Pb, and Zn in five tissues of marine gastropod Onchidium struma were studied in the Chongming Island, the Yangtze Estuary on July 2006, September 2006, and November 2006, April 2007, respectively. The results demonstrated that the bioconcentration factor of Cu (biomass/water) in all selected tissues was about 104 magnitudes, Fe and Cd were 103, Zn was 102, and Mn, Pb, and Cr were 101. Hepatopancreas was proven to be the dominant storage tissue of Cr, Cu, Mn, and Zn, whereas Fe and Pb were mainly stored in muscle and digenetic gland, and Cd was stored in vitelline gland and albumen gland. Additionally, it was found that Cu, Fe, Mn, and Zn were concentrated significantly by O. struma (whole-body) in summer or autumn, and Cd, Cr, and Pb increased slightly in spring and winter. Furthermore, the bioconcentration of Cr was nearly 2-fold higher and Zn was 1.6-fold higher in the water compared with the Water Quality Standard for Fisheries. With view of excessive amount of Pb, Cd, and Cu according to seafood standard, the consumption of O. struma might have the risk of health hazard.

  12. Fluctuating helical asymmetry and morphology of snails (Gastropoda in divergent microhabitats at 'Evolution Canyons I and II,' Israel.

    Directory of Open Access Journals (Sweden)

    Shmuel Raz

    Full Text Available BACKGROUND: Developmental instability of shelled gastropods is measured as deviations from a perfect equiangular (logarithmic spiral. We studied six species of gastropods at 'Evolution Canyons I and II' in Carmel and the Galilee Mountains, Israel, respectively. The xeric, south-facing, 'African' slopes and the mesic, north-facing, 'European' slopes have dramatically different microclimates and plant communities. Moreover, 'Evolution Canyon II' receives more rainfall than 'Evolution Canyon I.' METHODOLOGY/PRINCIPAL FINDINGS: We examined fluctuating asymmetry, rate of whorl expansion, shell height, and number of rotations of the body suture in six species of terrestrial snails from the two 'Evolution Canyons.' The xeric 'African' slope should be more stressful to land snails than the 'European' slope, and 'Evolution Canyon I' should be more stressful than 'Evolution Canyon II.' Only Eopolita protensa jebusitica showed marginally significant differences in fluctuating helical asymmetry between the two slopes. Contrary to expectations, asymmetry was marginally greater on the 'European' slope. Shells of Levantina spiriplana caesareana at 'Evolution Canyon I,' were smaller and more asymmetric than those at 'Evolution Canyon II.' Moreover, shell height and number of rotations of the suture were greater on the north-facing slopes of both canyons. CONCLUSIONS/SIGNIFICANCE: Our data is consistent with a trade-off between drought resistance and thermoregulation in snails; Levantina was significantly smaller on the 'African' slope, for increasing surface area and thermoregulation, while Eopolita was larger on the 'African' slope, for reducing water evaporation. In addition, 'Evolution Canyon I' was more stressful than Evolution Canyon II' for Levantina.

  13. On some Vetigastropoda (Mollusca, Gastropoda) from the Plio-Pleistocene of the Philippines with descriptions of three new species.

    Science.gov (United States)

    Helwerda, Renate Ariane; Wesselingh, Frank Pieter; Williams, Suzanne T

    2014-01-21

    We studied representatives of seven vetigastropod families in an extremely well-preserved Plio-Pleistocene mollusc fauna found in relatively deep water sediments (c. 200-300 m paleodepth) from the north-western Philippines. The fauna is systematically described and its paleoenvironmental and paleobiogeographical character is explored. Twenty-six species of gastropods were studied, three of which are described as new: Halystina conoidea n. sp., Calliotropis arenosa n. sp. and Ethminolia wareni n. sp. Four new combinations are proposed: Pseudotalopia taiwanensis (Chen, 2006), Solariella segersi (Poppe, Tagaro & Dekker, 2006), Zetela tabakotanii (Poppe, Tagaro & Dekker, 2006) and Ilanga konos (Vilvens, 2009). Fourteen species are known living. Most extant species nowadays occur around the Philippines. Two of the species also occur in Neogene deposits from western Pacific islands. The new fauna offers insights into the character of relatively deep water Indo-West Pacific mollusc faunas prior to the onset of the late Quaternary ice ages.

  14. Sequence and comparison of mitochondrial genomes in the genus Nerita (Gastropoda: Neritimorpha: Neritidae) and phylogenetic considerations among gastropods.

    Science.gov (United States)

    Arquez, Moises; Colgan, Donald; Castro, Lyda R

    2014-06-01

    In the present study, we determined the mitochondrial DNA (mtDNA) sequence of three Neritas, Nerita versicolor, Nerita tessellata, and Nerita fulgurans. We present an analysis of the features of their gene content and genome organization and compare these within the genus Nerita, and among the main gastropod groups. The new sequences were used in a phylogenetic analysis including all available gastropod mitochondrial genomes. Genomic lengths were quite conserved, being 15,866bp for N. versicolor, 15,741bp for N. tessellata and 15,343bp for N. fulgurans. Intergenic regions were generally short; genes are transcribed from both strands and have a nucleotide composition high in A and T. The high similarity in nucleotide content of the different sequences, gene composition, as well as an identical genomic organization among the Nerita species compared in this study, indicates a high degree of conservation within this diverse genus. Values ​​of Ka/Ks of the 13 protein coding genes (PCGs) of Nerita species ranged from 0 to 0.18, and suggested different selection pressures in gene sequences. Bayesian phylogenetic analyses using concatenated DNA sequences of the 13 PCGs and the two rRNAs, and of amino acid sequences strongly supported Neritimorpha and Vetigastropoda as sister groups.

  15. Contribution to the knowledge of the gastropods (Gastropoda, Pulmonata of Ilinska and Plakinska Mountains (Republic of Macedonia

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    IVAYLO DEDOV

    2015-06-01

    Full Text Available The work presents results of a collecting trip in July 2008 in the mountains Ilinska and Plakinska (Republic of Macedonia. The work summarizes data for distribution and ecology of 19 species from the mountains. The data collected during the expedition provide the first information for terrestrial gastropods in this region of Macedonia.

  16. Differences in osmotolerance in freshwater and brackish water populations of Theodoxus fluviatilis (Gastropoda: Neritidae) are associated with differential protein expression.

    Science.gov (United States)

    Symanowski, Frauke; Hildebrandt, Jan-Peter

    2010-03-01

    The euryhaline gastropod Theodoxus fluviatilis is found in northern Germany in freshwater or in brackish water habitats in the Baltic Sea. Previous studies have revealed that individuals from both habitats are not distinguishable by morphological characters or by sequence comparison of DNA encoding 16S RNA or cytochrome C. As reported in this study, animals collected in the two habitats differ substantially in their physiological ability to adapt to different salinities. Comparison of accumulation rates of ninhydrin-positive substances (NPS) in foot muscle upon transfer of animals to higher medium salinities revealed that brackish water animals were perfectly able to mobilize NPS, while freshwater animals had only limited ability to do so. In an attempt to explore whether this difference in physiology may be caused by genetic differentiation, we compared protein expression patterns of soluble foot muscle proteins using 2D gel electrophoresis and silver staining. Of the 40 consistently detected protein spots, 27 showed similar levels in protein expression in animals collected from freshwater or brackish water habitats, respectively. In 12 spots, however, protein concentration was higher in brackish water than in freshwater animals. In four of these spots, expression levels followed increases or decreases in medium salinities. In a different set of 4 of these 12 spots, protein levels were always higher in brackish water as compared to freshwater animals, regardless of their physiological situation (14 days in artificial pond water or in medium with a salinity of 16 per thousand). The remaining 4 of the 12 spots had complex expression patterns. Protein levels of the remaining single spot were generally higher in freshwater animals than in brackish water animals. These expression patterns may indicate that freshwater and brackish water animals of T. fluviatilis belong to different locally adapted populations with subtle genetic differentiation.

  17. Molecular phylogenetic investigations of the Viviparidae (Gastropoda: Caenogastropoda) in the lakes of the Rift Valley area of Africa.

    Science.gov (United States)

    Sengupta, Mita E; Kristensen, Thomas K; Madsen, Henry; Jørgensen, Aslak

    2009-09-01

    The freshwater gastropod family Viviparidae is nearly cosmopolitan, but absent from South America. On the African continent, two genera are recognized; the widespread Bellamya and the monotypic Neothauma, which is confined to Lake Tanganyika. Most of the African Bellamya species are confined to the major lakes of the Rift Valley area in Africa, i.e. Lake Albert, Lake Malawi, Lake Mweru, and Lake Victoria. The phylogenetic analyses of mitochondrial (COI and 16S) and nuclear (H3, 18S and 28S) DNA inferred three major lake-clades; i.e. Lake Victoria/Kyoga/Albert, Lake Malawi and Lake Mweru/Bangweulu. The endemic B. rubicunda from Lake Albert and B. unicolor from Lake Kyoga were inferred to be part of the Lake Victoria clade. Bellamya capillata as identified by shell characters was polyphyletic in gene trees. The monophyletic Bellamya species radiation in Lake Malawi was most nearly related to the Lake Victoria/Kyoga/Albert-clade. Taxa from the Zambian lakes, Mweru and Bangweulu, were inferred together and placed ancestral to the other lakes. Neothauma tanganyicense was inferred as the sister-group to the Zambian Bellamya. Within the lake-clades the endemic radiations show very low genetic diversities (0-4.1% in COI), suggesting much faster morphological divergence than molecular divergence. Alternatively, Bellamya in Africa constitutes only a few species with several sub-species or eco-phenotypic morphs. The African viviparids were inferred to be the sister-group to a clade comprising Asian species, and the relatively low genetic diversity between the clades (12.6-15.5% in COI) makes a recent Miocene dispersal event from Asia to Africa much more likely than an ancient Gondwana vicarience distribution.

  18. Composición de ácidos grasos de los caracoles marinos Phyllonotus pomum y Chicoreus brevifrons (Gastropoda: Muricidae)

    OpenAIRE

    2009-01-01

    Se comparó el contenido de ácidos grasos en los lípidos totales de los caracoles Phyllonotus pomum y Chicoreus brevifrons, recolectados en tres diferentes épocas del año en Punta Arena, estado Sucre, Venezuela. Las concentraciones lipídicas oscilaron entre 0.87 y 1.85%, correspondiendo el valor mínimo y el máximo a C. brevifrons colectado en lluvia y sequía, respectivamente. La esterificación de los ácidos grasos presentes en estos lípidos seguida de la cromatografía de gases permitió la cara...

  19. Distribution Of The Freshwater Snail Species Fagotia (Gastropoda, Melanopsidae In Ukraine According To Climatic Factors. I. Fagotia Esperi

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    Tytar V.

    2015-08-01

    Full Text Available Maximum entropy niche modeling was employed as a tool to assess potential habitat suitability for the freshwater snail F. esperi (Férussac, 1823 in Ukraine for both contemporary climatic conditions and conditions projected for 2050. Of the 19 bioclimatic predictor variables used in the modeling, the “mean temperature seosonality” “mean temperature of driest quarter” and “precipitation of warmest quarter” were the three most important in predicting habitat suitability and distribution of this mollusk species.

  20. Revision of Partulidae (Gastropoda, Stylommatophora) of Palau, with description of a new genus for an unusual ground-dwelling species

    Science.gov (United States)

    Slapcinsky, John; Kraus, Fred

    2016-01-01

    Abstract We describe a new stylommatophoran land snail of the family Partulidae from Palau. The new species has a combination of morphological and ecological characters that do not allow its placement in any existing partulid genus, so we describe a new genus for it. The new genus is characterized by a large (18–23 mm) obese-pupoid shell; smooth protoconch; teleoconch with weak and inconsistent, progressively stronger, striae; last half of body whorl not extending beyond the penultimate whorl; widely expanded and reflexed peristome; relatively long penis, with longitudinal pilasters that fuse apically into a fleshy ridge that divides the main chamber from a small apical chamber; and vas deferens entering and penial-retractor muscle attaching at the apex of the penis. Unlike all other partulids, the new species is strictly associated with rocks in contact with the ground. Comparing the other three Palauan species – currently assigned to Partula – to our new genus and to other partulids makes it clear that they require their own genus because their morphology is quite different from that of true Partula and from that of all other genera. Hence, we resurrect the name Palaopartula Pilsbry for these snails. PMID:27667931

  1. Development and validation of an OECD reproductive toxicity test guideline with the pond snail Lymnaea stagnalis (Mollusca, Gastropoda).

    Science.gov (United States)

    Ducrot, Virginie; Askem, Clare; Azam, Didier; Brettschneider, Denise; Brown, Rebecca; Charles, Sandrine; Coke, Maïra; Collinet, Marc; Delignette-Muller, Marie-Laure; Forfait-Dubuc, Carole; Holbech, Henrik; Hutchinson, Thomas; Jach, Arne; Kinnberg, Karin L; Lacoste, Cédric; Le Page, Gareth; Matthiessen, Peter; Oehlmann, Jörg; Rice, Lynsey; Roberts, Edward; Ruppert, Katharina; Davis, Jessica Elphinstone; Veauvy, Clemence; Weltje, Lennart; Wortham, Ruth; Lagadic, Laurent

    2014-12-01

    The OECD test guideline development program has been extended in 2011 to establish a partial life-cycle protocol for assessing the reproductive toxicity of chemicals to several mollusk species, including the great pond snail Lymnaea stagnalis. In this paper, we summarize the standard draft protocol for a reproduction test with this species, and present inter-comparison results obtained in a 56-day prevalidation ring-test using this protocol. Seven European laboratories performed semi-static tests with cultured snails of the strain Renilys® exposed to nominal concentrations of cadmium chloride (from 53 to 608μgCdL(-1)). Cd concentrations in test solutions were analytically determined to confirm accuracy in the metal exposure concentrations in all laboratories. Physico-chemical and biological validity criteria (namely dissolved oxygen content >60% ASV, water temperature 20±1°C, control snail survival >80% and control snail fecundity >8 egg-masses per snail over the test period) were met in all laboratories which consistently demonstrated the reproductive toxicity of Cd in snails using the proposed draft protocol. Effect concentrations for fecundity after 56days were reproducible between laboratories (68

  2. Bulinus globosus (Planorbidae; Gastropoda) populations in the Lake Victoria basin and coastal Kenya show extreme nuclear genetic differentiation.

    Science.gov (United States)

    Nyakaana, Silvester; Stothard, J Russell; Nalugwa, Allen; Webster, Bonnie L; Lange, Charles N; Jørgensen, Aslak; Rollinson, David; Kristensen, Thomas K

    2013-11-01

    Bulinus globosus, a key intermediate host for Schistosoma haematobium that causes urinary schistosomiasis, is a hermaphroditic freshwater Planorbid snail species that inhabits patchy and transient water bodies prone to large seasonal variations in water availability. Although capable of self-fertilizing, this species has been reported to be preferentially out crossing. In this study, we characterized the population genetic structure of 19 B. globosus populations sampled across the Lake Victoria basin and coastal Kenya using four polymorphic microsatellite loci. Population genetic structure was characterized and quantified using FST statistics and Bayesian clustering algorithms. The four loci used in this study contained sufficient statistical power to detect low levels of population genetic differentiation and were highly polymorphic with the number of alleles per locus across populations ranging from 16 to 22. Average observed and expected heterozygosities across loci in each population ranged from 0.13 to 0.69 and from 0.39 to 0.79, respectively. Twenty-five of the seventy-six possible population-locus comparisons significantly deviated from Hardy-Weinberg equilibrium proportions after Bonferroni corrections, mostly due to the deficiency of heterozygotes. Significant genetic differentiation was observed between populations and Bayesian inferences identified 15 genetic clusters. The excess homozygosity, significant inbreeding and population genetic differentiation observed in B. globosus populations are likely to be due to the habitat patchiness, mating system and the proneness to cyclic extinction and recolonization in transient habitats.

  3. Changes in body size spectra of benthic caridean shrimps (Decapoda: Caridea) and snails (Gastropoda) as response to seasonal variability

    OpenAIRE

    2016-01-01

    Ecologists have been largely interested in the description and understanding of the power scaling relationships between body size and abundance of organisms. Many studies have focused on estimating the exponents of these functions across taxonomic groups and spatial scales, to draw inferences about the processes underlying this pattern. The exponents of these functions usually approximate -3/4 at geographical scales, but they deviate from this value when smaller spatial extensions are conside...

  4. The nudibranch names mentioned as n.sp. in Bergh (1861) are almost all nomina nuda (Gastropoda: Heterobranchia: Nudibranchia).

    Science.gov (United States)

    Jensen, Kathe; Nielsen, Claus

    2014-01-06

    In a publication in Danish from 1861, Bergh described the nematocysts found in a number of nudibranch species. Many of the species had been described previously, but a number were new and given names, but without a description. These species are nomina nuda. We have translated the "descriptions", including the foot-notes, and reproduced the original plate to show that only the nematocysts (real or assumed) were described. The only species given a short description fulfilling the requirements of the ICZN is Pleurophyllidia quadrilateralis, which was described as the only species in the new genus Sancara. This in turn was shown to be a junior synonym of Linguella de Blainville, 1823. All the species were subsequently described anatomically in detail and made valid in a number of papers, and most of the type material is located in the Zoological Museum, Copenhagen (Natural History Museum of Denmark). The names in current use have been given.

  5. Opisthobranchs from the western Indian Ocean, with descriptions of two new species and ten new records (Mollusca, Gastropoda

    Directory of Open Access Journals (Sweden)

    Nathalie Yonow

    2012-05-01

    Full Text Available Seventy species of opisthobranchs are described in this work based on collections from the Persian Gulf, Socotra, Kenya, Zanzibar, Madagascar, La Réunion, Mauritius, the Seychelles, the Maldives, and Sri Lanka. Ten species are newly recorded from the western Indian Ocean and four species are recorded in the scientific literature for the first time since their original descriptions. Two species are described as new: Cyerce bourbonica sp. n. from La Réand Doriopsilla nigrocera sp. n. from the Persian Gulf coast of Saudi Arabia. Chromodoris cavae is removed from its synonymy with C. tennentana and redescribed from specimens from La Réunion, while several new synonyms are proposed for some commonly occurring species. Risbecia bullockii is recorded for the second time from the Indian Ocean and assigned to its correct genus.

  6. Subgeneric division of the genus Orcula Held 1837 with remarks on Romanian orculid data (Gastropoda, Pulmonata, Orculidae

    Directory of Open Access Journals (Sweden)

    Barna Pall-Gergely

    2013-05-01

    Full Text Available The genital anatomy of Orcula jetschini (Romania, O. zilchi (Bulgaria and O. wagneri (Albania is described. Based on anatomical features (morphology of the penial caecum, shell characters (sculpture and shape and unpublished molecular data, the genus Orcula is subdivided into three subgenera. O. zilchi was classified within the monotypic subgenus Orcula (Hausdorfia subgen. n.; O. jetschini, O. wagneri and O. schmidtii were classified to Orcula (Illyriobanatica subgen. n. (type species: Pupa Schmidtii, whereas the other Orcula species remain in the nominotypical subgenus. Orcula (Hausdorfia is known from South-Eastern Bulgaria and North-Western Turkey, Orcula (Illyriobanatica inhabits Western Romania, North-Western Greece, Albania, Macedonia, Kosovo and Montenegro. The nine species of Orcula (Orcula are known mainly from the Alps and the Western Carpathians (from Eastern France to Eastern Hungary and Slovakia.The occurrence of only one Orcula species, namely O. jetschini is verified from Romania. Available information suggests that data on the Romanian occurrence of Orcula dolium and O. gularis were based on wrongly identified specimens. Sphyradium dobrogicum (=Orcula dobrogica is considered as a synonym of S. doliolum.

  7. No Evidence for a Culturable Bacterial Tetrodotoxin Producer in Pleurobranchaea maculata (Gastropoda: Pleurobranchidae and Stylochoplana sp. (Platyhelminthes: Polycladida

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    Lauren R. Salvitti

    2015-01-01

    Full Text Available Tetrodotoxin (TTX is a potent neurotoxin found in the tissues of many taxonomically diverse organisms. Its origin has been the topic of much debate, with suggestions including endogenous production, acquisition through diet, and symbiotic bacterial synthesis. Bacterial production of TTX has been reported in isolates from marine biota, but at lower than expected concentrations. In this study, 102 strains were isolated from Pleurobranchaea maculata (Opisthobranchia and Stylochoplana sp. (Platyhelminthes. Tetrodotoxin production was tested utilizing a recently developed sensitive method to detect the C9 base of TTX via liquid chromatography—mass spectrometry. Bacterial strains were characterized by sequencing a region of the 16S ribosomal RNA gene. To account for the possibility that TTX is produced by a consortium of bacteria, a series of experiments using marine broth spiked with various P. maculata tissues were undertaken. Sixteen unique strains from P. maculata and one from Stylochoplana sp. were isolated, representing eight different genera; Pseudomonadales, Actinomycetales, Oceanospirillales, Thiotrichales, Rhodobacterales, Sphingomonadales, Bacillales, and Vibrionales. Molecular fingerprinting of bacterial communities from broth experiments showed little change over the first four days. No C9 base or TTX was detected in isolates or broth experiments (past day 0, suggesting a culturable microbial source of TTX in P. maculata and Stylochoplana sp. is unlikely.

  8. No evidence for a culturable bacterial tetrodotoxin producer in Pleurobranchaea maculata (Gastropoda: Pleurobranchidae) and Stylochoplana sp. (Platyhelminthes: Polycladida).

    Science.gov (United States)

    Salvitti, Lauren R; Wood, Susanna A; McNabb, Paul; Cary, Stephen Craig

    2015-01-28

    Tetrodotoxin (TTX) is a potent neurotoxin found in the tissues of many taxonomically diverse organisms. Its origin has been the topic of much debate, with suggestions including endogenous production, acquisition through diet, and symbiotic bacterial synthesis. Bacterial production of TTX has been reported in isolates from marine biota, but at lower than expected concentrations. In this study, 102 strains were isolated from Pleurobranchaea maculata (Opisthobranchia) and Stylochoplana sp. (Platyhelminthes). Tetrodotoxin production was tested utilizing a recently developed sensitive method to detect the C9 base of TTX via liquid chromatography-mass spectrometry. Bacterial strains were characterized by sequencing a region of the 16S ribosomal RNA gene. To account for the possibility that TTX is produced by a consortium of bacteria, a series of experiments using marine broth spiked with various P. maculata tissues were undertaken. Sixteen unique strains from P. maculata and one from Stylochoplana sp. were isolated, representing eight different genera; Pseudomonadales, Actinomycetales, Oceanospirillales, Thiotrichales, Rhodobacterales, Sphingomonadales, Bacillales, and Vibrionales. Molecular fingerprinting of bacterial communities from broth experiments showed little change over the first four days. No C9 base or TTX was detected in isolates or broth experiments (past day 0), suggesting a culturable microbial source of TTX in P. maculata and Stylochoplana sp. is unlikely.

  9. Antimicrobial activities of the tissue extracts of Babylonia spirata Linnaeus, 1758 (Mollusca:Gastropoda) from Thazhanguda, southeast coast of India

    Institute of Scientific and Technical Information of China (English)

    Periyasamy N; Srinivasan M; Balakrishnan S

    2012-01-01

    Objective: To investigate the antimicrobial activity of the tissue extracts of Babylonia spirata (B. spirata) against nine bacterial and three fungal pathogens. Methods: Crude extract of gastropod was tested for inhibition of bacterial and fungal growth. Antibacterial assay was carried out by disc diffusion method and in vitro antifungal activity was determined against Czapex Dox agar. The antimicrobial activity was measured accordingly based on the inhibition zone around the disc impregnated with gastropod extract. Molecular size of muscle protein was determined using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). And fourier transform infrared spectroscopy (FTIR) spectro photometry analysis was also studied. Results:The maximum inhibition zone (12 mm) was observed against Pseudomonas aeruginosa in the crude ethanol extract of B. spirata and the minimum inhibition zone (2 mm) was noticed againstStaphylococcus aureus in the crude methanol extract of B. spirata. Water extract of B. spirata showed the highest activity against Vibrio parahaemolyticus, Staphylococcus aureus and Candidaalbicans. Ethanol, acetone, methanol, chloroform and water extracts showed antimicrobial activity against almost all the bacteria and fungus. Compared with water extracts, ethanol and methanol extracts showed higher activity against all pathogens. The molecular weight of protein of the gastropod sample ranged from 2-110 kDa on SDS-PAGE. FTIR analysis revealed the presence of bioactive compounds signals at different ranges. Conclusions: The research shows that the great medicinal value of the gastropod muscle of B. spirata may be due to high quality of antimicrobial compounds.

  10. The complete mitochondrial genome of Haliotis laevigata (Gastropoda: Haliotidae) using MiSeq and HiSeq sequencing.

    Science.gov (United States)

    Robinson, Nick A; Hall, Nathan E; Ross, Elizabeth M; Cooke, Ira R; Shiel, Brett P; Robinson, Andrew J; Strugnell, Jan M

    2016-01-01

    The mitochondrial genome of greenlip abalone, Haliotis laevigata, is reported. MiSeq and HiSeq sequencing of one individual was assembled to yield a single 16,545 bp contig. The sequence shares 92% identity to the H. rubra mitochondrial genome (a closely related species that hybridize with H. laevigata in the wild). The sequence will be useful for determining the maternal contribution to hybrid populations, for investigating population structure and stock-enhancement effectiveness.

  11. A Miocene molluscan faunule from Caucagua (Miranda State, Venezuela), with the description of a new species of Tryonia (Mollusca, Gastropoda)

    NARCIS (Netherlands)

    Wesselingh, F.P.; Macsotay, O.

    2006-01-01

    A molluscan faunule from the Miocene Cumaca Formation of the western margin of the Tuy Basin (Venezuela) is described. The fauna yields two species of freshwater snails and a single terrestrial snail species. Tryonia vivasi nov. spec. is described from the fauna, and its biogeographical significance

  12. New narrow-range endemic land snails from the sky islands of northern South Africa (Gastropoda: Streptaxidae and Urocyclidae

    Directory of Open Access Journals (Sweden)

    David G. Herbert

    2016-10-01

    Full Text Available One new genus and five new species of land snails are described from high altitude, insular, Afrotemperate forest habitats in northern South Africa. The distribution of these species is discussed in relation to other narrowly endemic land snails occurring in this and neighbouring regions. The new genus is Ptilototheca gen. nov.; the five new species are: Gulella davisae sp. nov., G. hadroglossa sp. nov., Ptilototheca soutpansbergensis gen. et sp. nov., Sheldonia monsmaripi sp. nov. and S. wolkbergensis sp. nov.

  13. Freshwater snails (Mollusca: Gastropoda) from the Commonwealth of Dominica with a discussion of their roles in the transmission of parasites

    Science.gov (United States)

    We collected six species of freshwater snails from Dominica, including Biomphalaria kuhniana, Gundlachia radiata Helisoma (= Planorbella) trivolvis, Melanoides tuberculata, Neritina punctulata, and Physa marmorata. Our collections indicate that un-reported species such as Gundlachia radiata and Hel...

  14. Eco-physiological adaptation of the land snail Achatina achatina (Gastropoda: Pulmonata in tropical agro-ecosystem

    Directory of Open Access Journals (Sweden)

    Christian O. Chukwuka

    2014-03-01

    Full Text Available The survival of land snails in an adverse environmental condition depends on the integral physiological, morphological and behavioural adaptations. These adaptations are essential in understanding the species-specific habitat requirements and in predicting their environmental responses. In this study, the monthly and the periodic patterns of eco-physiological adaptation of land snail, Achatina achatina in Nsukka tropical agro-ecosystem were assessed from December 2012 to July 2013. Standard methods were employed in sampling the land snail and determination of the water content, biochemical fuel reserves and enzyme concentrations of the samples. The present results showed that lipids were high at the beginning of aestivation and depleted as the aestivation progressed. Glycogen was significantly low throughout the aestivation months (December–March and increased in the active months (April–July. Protein content recorded a definite pattern all through the months studied. Catabolism of lactate and a decrease in activity of LDH during aestivation and substantial increase upon activation were observed. Data showed that transaminase and aspartate enzymes depleted during the aestivation months indicating that the snails may have developed potential cell injury due to oxidative stress and thermal heat. A disassociation between the physiological responses and climatic data was recorded. The physiological adaptation of A. achatina ensures regular adjustment under extreme conditions and compensates for its metabolic regulation in the tropics. It is concluded that survival of A. achatina is not environmentally predicted; rather it depends on the species-specific inherent process in predicting responses for survival.

  15. Neosataria, replacement name for Sataria Annandale, 1920 (Mollusca: Gastropoda: Bithyniidae), preoccupied by Sataria Roewer, 1915 (Arachnida: Opiliones: Sclerosomatidae).

    Science.gov (United States)

    Kulkarni, Siddharth; Khot, Rahul

    2015-06-24

    The family Bithyniidae is represented in tropical Asia by the following genera, Bithynia, Digonistoma, Mysorella, Parabithynia, Emmericiopsis, Hydrobioides, Parafossarulus, Pseudovivipara, Sataria and Wattebladia (Dudgeon 1999; Pyron & Brown 2015).

  16. The ibero-balearic region: one of the areas of highest Hydrobiidae (Gastropoda, Prosobranchia, Rissooidea diversity in Europe

    Directory of Open Access Journals (Sweden)

    Arconada, Beatriz

    2003-12-01

    Full Text Available The prosobranch mollusc family Hydrobiidae Troschel, 1857 has a cosmopolitan distribution and is made up of small to minute species that inhabit permanent aquatic ecosystems. It is one of the largest families within the superfamily Rissooidea. The evolutionary relationships between members of this family are still unclear due to: 1 insufficient available information regarding the morphological characters of many of the described taxa, 2 uncertainty concerning which morphological characters are of greatest taxonomic and phylogenetic interest, and 3 the rare use of molecular characters to study evolutionary relationships. In this work, we examine the reasons for the confusing systematics of hydrobiids. We include a diagnosis of the 13 genera and a list of the 43 species described and accepted to date for the Ibero-balearic region, along with data regarding their geographic distribution and a compilation of the most relevant bibliographical references. The Iberian Peninsula is one of the areas of greatest hydrobiid diversity in Europe, and has a large number of endemic genera and species in addition to those that have a typically circummediterranean distribution. Numerous hydrobiid species and populations are threatened, and in some cases, in danger of extinction due to the fragile nature of many of the ecosystems they inhabit.

    La familia Hydrobiidae Troschel, 1857 de moluscos prosobranquios, tiene distribución cosmopolita y está constituida por especies de tamaño pequeño (o incluso diminuto que habitan ecosistemas acuáticos permanentes. Se trata de una de las familias con mayor número de especies de la superfamilia Rissooidea. Las relaciones evolutivas entre los miembros de esta familia son aún confusas debido a: (1 la insuficiente información disponible sobre los caracteres morfológicos de muchos de los táxones descritos, (2 la indefinición de los caracteres morfológicos de interés taxonómico y filogenético, y (3 la escasa aplicación de los caracteres moleculares para este fin. En este trabajo se revisa la confusa sistemática de los hidróbidos y sus causas. Además, se incluye una diagnosis de los 13 géneros y un listado de las 43 especies hasta ahora descritas y aceptadas en el ámbito ibero-balear, con datos sobre su distribución geográfica y la bibliografía más relevante. Se constata que la Península Ibérica constituye una de las áreas de mayor diversidad de hidróbidos en Europa, conteniendo un alto número de géneros y especies endémicos a los que se añaden otros de distribución circunmediterránea. La fragilidad de muchos de los ecosistemas en los que viven hace que muchas de sus especies y/o poblaciones se hallen amenazadas e incluso en peligro de extinción.

  17. Developmental toxicity of metaldehyde in the embryos of Lymnaea stagnalis (Gastropoda: Pulmonata) co-exposed to the synergist piperonyl butoxide.

    Science.gov (United States)

    Hallett, Katrina C; Atfield, Andrew; Comber, Sean; Hutchinson, Thomas H

    2016-02-01

    Metaldehyde is a widely used molluscicide in countries where damage to crops from slugs and snails is a major problem associated with warm and wet winters. In the UK it is estimated that over 8% of the area covered by arable crops is treated with formulated granular bait pellets containing metaldehyde as the main active ingredient. Metaldehyde is hydrophilic (log Kow=0.12), water soluble (200 mg·L(-1) at 17 °C) and has been detected in UK surface waters in the concentration range of typically 0.2-0.6 μg·L(-1) (maximum 2.7 μg·L(-1)) during 2008-2011. In the absence of chronic data on potential hazards to non-target freshwater molluscs, a laboratory study was conducted to investigate the impact of metaldehyde on embryo development in the gastropod Lymnaea stagnalis (RENILYS strain) and using zinc as a positive control. L. stagnalis embryos were exposed to metaldehyde under semi-static conditions at 20±1 °C and hatching success and growth (measured as shell height and intraocular distance) examined after 21 d. Exposure concentrations were verified using HPLC and gave 21 d (hatching)NOEC and (hatching)LOEC mean measured values of 36 and 116 mg MET·L(-1), respectively (equal to the 21 d (shell height)NOEC and (shell height)LOEC values). For basic research purposes, a second group of L. stagnalis embryos was co-exposed to metaldehyde and the pesticide synergist piperonyl butoxide (PBO). Co-exposure to the PBO (measured concentrations between 0.47-0.56 mg·L(-1)) reduced hatching success from 100% to 47% and resulted in a 30% reduction in embryo growth (shell height) in snail embryos co-exposed to metaldehyde at 34-36 mg·L(-1) over 21 d. In conclusion, these data suggest mollusc embryos may have some metabolic detoxication capacity for metaldehyde and further work is warranted to explore this aspect in order to support the recent initiative to include molluscs in the OECD test guideline programme.

  18. Developmental toxicity, acute toxicity and mutagenicity testing in freshwater snails Biomphalaria glabrata (Mollusca: Gastropoda) exposed to chromium and water samples.

    Science.gov (United States)

    Tallarico, Lenita de Freitas; Borrely, Sueli Ivone; Hamada, Natália; Grazeffe, Vanessa Siqueira; Ohlweiler, Fernanda Pires; Okazaki, Kayo; Granatelli, Amanda Tosatte; Pereira, Ivana Wuo; Pereira, Carlos Alberto de Bragança; Nakano, Eliana

    2014-12-01

    A protocol combining acute toxicity, developmental toxicity and mutagenicity analysis in freshwater snail Biomphalaria glabrata for application in ecotoxicological studies is described. For acute toxicity testing, LC50 and EC50 values were determined; dominant lethal mutations induction was the endpoint for mutagenicity analysis. Reference toxicant potassium dichromate (K2Cr2O7) was used to characterize B. glabrata sensitivity for toxicity and cyclophosphamide to mutagenicity testing purposes. Compared to other relevant freshwater species, B. glabrata showed high sensitivity: the lowest EC50 value was obtained with embryos at veliger stage (5.76mg/L). To assess the model applicability for environmental studies, influent and effluent water samples from a wastewater treatment plant were evaluated. Gastropod sensitivity was assessed in comparison to the standardized bioassay with Daphnia similis exposed to the same water samples. Sampling sites identified as toxic to daphnids were also detected by snails, showing a qualitatively similar sensitivity suggesting that B. glabrata is a suitable test species for freshwater monitoring. Holding procedures and protocols implemented for toxicity and developmental bioassays showed to be in compliance with international standards for intra-laboratory precision. Thereby, we are proposing this system for application in ecotoxicological studies.

  19. Philinidae, Laonidae and Philinorbidae (Gastropoda: Cephalaspidea: Philinoidea) from the northeastern Pacific Ocean and the Beaufort Sea (Arctic Ocean).

    Science.gov (United States)

    Valdés, Ángel; Cadien, Donald B; Gosliner, Terrence M

    2016-08-08

    Based on morphological data a total of nine native species of Philinidae are recognized from the northeastern Pacific including the Bering Sea and the adjacent Arctic Ocean (Beaufort Sea). Four of them have been previously described: Philine ornatissima Yokoyama, 1927, Philine bakeri Dall, 1919, Philine polystrigma (Dall, 1908), and Philine hemphilli Dall, 1919. Five of them are new and described herein: Philine mcleani sp. nov., Philine baxteri sp. nov., Philine malaquiasi sp. nov., Philine wareni sp. nov., and Philine harrisae sp. nov. These species display a substantial degree of variation in internal and external morphological traits (i.e., presence/absence of gizzard plates, different radular structure and tooth morphology, various reproductive anatomical features) and it is likely that they belong to different clades (genera). However, in the absence of a comprehensive phylogeny for Philine, they are here provisionally regarded as Philine sensu lato. In addition to the nine native species, two introduced species: Philine orientalis A. Adams, 1854 and Philine auriformis Suter, 1909 are here illustrated and compared to the native species to facilitate identification. Finally, two species previously considered members of Philinidae are examined anatomically and confirmed as members of Laonidae, Laona californica (Willett, 1944) and Philinorbidae, Philinorbis albus (Mattox, 1958), based on morphological data.

  20. Histologia da glândula de albúmen de Pomacea canaliculata (Lamarck, 1822 (Mollusca, Gastropoda, Pilidae

    Directory of Open Access Journals (Sweden)

    Eliane de Fátima Marques de Mesquita

    1990-01-01

    Full Text Available In this paper the authors give a histological analysis of the albumen gland of mature and immature females of Pomacea canaliculata (Lamarck, 1822. In the immaturity, tthe gland doesn't show any secretory activity, although in the maturity this activity is indicated by the presence of a homogeneous and eosinophilic material in its lumen. We could notice in the capsule gland of matures females a calcareous element is present as a granular and basophilic deposit. The albumen gland is envolved by a thin conjunctive layer that can be seen in van Gieson's coloured preparations.

  1. Putative midkine family protein up-regulation in Patella caerulea (Mollusca, Gastropoda) exposed to sublethal concentrations of cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Vanucci, Silvana [Department of Animal Biology and Marine Ecology, University of Messina, Salita Sperone 31, 98166 S Agata, Messina (Italy)]. E-mail: silvana.vanucci@unime.it; Minerdi, Daniela [Department of Animal Biology and Genetics, University of Florence, via Romana 19, 50125 Florence (Italy); Kadomatsu, Kenji [Department of Biochemistry, University of Nagoya Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Mengoni, Alessio [Department of Animal Biology and Genetics, University of Florence, via Romana 19, 50125 Florence (Italy); Bazzicalupo, Marco [Department of Animal Biology and Genetics, University of Florence, via Romana 19, 50125 Florence (Italy)

    2005-11-30

    A cDNA sequence of a putative midkine (MK) family protein was identified and characterised in the mollusc Patella caerulea. The midkine family consists of two members, midkine and pleiotrophin (PTN), and it is one of the recently discovered cytokines. Our results show that this putative midkine protein is up-regulated in specimens of P. caerulea exposed to sublethal cadmium concentrations (i.e. 0.5 and 1 mg l{sup -1} Cd) over a 10-day exposure period. Semiquantitative RT-PCR and quantitative Real time RT-PCR estimations indicate elevated expression of midkine mRNA in exposed specimens compared to controls. Moreover, RT-PCR Real time values were higher in the viscera (here defined as the part of the soft tissue including digestive gland plus gills) than in the foot (i.e. foot plus head plus heart) of the limpets. At present, information on the functional signalling significance of the midkine family proteins suggests that the up-regulation of P. caerulea putative midkine family protein is a distress signal likely with informative value on health status of the organism and with potential prognostic capability.

  2. Bulinus globosus (Planorbidae; Gastropoda) populations in the Lake Victoria basin and coastal Kenya show extreme nuclear genetic differentiation

    DEFF Research Database (Denmark)

    Nyakaana, Silvester; Stothard, J. Russell; Nalugwa, Allen

    2013-01-01

    -fertilizing, this species has been reported to be preferentially out crossing. In this study, we characterized the population genetic structure of 19 B. globosus populations sampled across the Lake Victoria basin and coastal Kenya using four polymorphic microsatellite loci. Population genetic structure was characterized...

  3. [Genetic diversity in two populations of the snail Strombus gigas (Gastropoda: Strombidae) from Yucatan, Mexico, using microsatellite].

    Science.gov (United States)

    Zamora-Bustillos, Roberto; Rodríguez-Canul, Rossanna; García de León, Francisco J; Tello Cetina, Jorge

    2011-09-01

    The pink conch Strombus gigas is an important fisheries resource in the Caribbean region, including the Yucatán Peninsula. We analyzed the genetic diversity and genetic structure of two populations (Alacranes Reef and Chinchorro Bank) with the use of five microsatellite molecular markers. The results indicate that the two populations are in the same rank of genetic diversity (He), from 0.613 to 0.692. Significant deviation from H-WE was observed in the both populations due to deficit to heterozygotes, this was attributed to inbreeding as a consequence of over-fishing; nevertheless, other possible causes considered are mixing of individuals from two or more populations, and the existence of null alleles. Levels of genetic differentiation indicated the existence of a single homogenous population in the Yucatan Peninsula (F(ST) de 0.003, p = 0.49), which fits with highest levels of gene flow is significant (2.3 individuals) between both populations. Results from this study support the hypothesis that S. gigas is part of a single panmictic population in the Yucatan Peninsula; therefore, this fishery resource should be regulated the same way for both areas.

  4. Biosynthesis and composition of sterols and sterol esters in the land snail Cepaea nemoralis (L.) (gastropoda, pulmonata, stylommatophora)

    NARCIS (Netherlands)

    Horst, D.J. van der; Voogt, P.A.

    1972-01-01

    1. 1. The biosynthesis and composition of sterols and sterol esters were studied in the land snail Cepaea nemoralis after injection of Na-1-14C-acetate. 2. 2. Free and esterified sterols appeared to be synthesized by the animals, whilst the specific radioactivity of the sterols from the esters was

  5. On Trichia alpicola (Eder, 1921) from Switzerland (Mollusca: Gastropoda Pulmonata: Hygromiidae) and the spiral sculpture on its shell

    NARCIS (Netherlands)

    Gittenberger, E.; Neuteboom, W.H.

    1991-01-01

    The nominal taxon Fruticicola villosa var. alpicola Eder, 1921, is provisionally considered a separate Trichia species next to T. villosa. The hairs and the spiral sculpture on the shells of both species are illustrated.

  6. Two complete mitochondrial genomes from Praticolella mexicana Perez, 2011 (Polygyridae) and gene order evolution in Helicoidea (Mollusca, Gastropoda)

    Science.gov (United States)

    Minton, Russell L.; Cruz, Marco A. Martinez; Farman, Mark L.; Perez, Kathryn E.

    2016-01-01

    Abstract Helicoidea is a diverse group of land snails with a global distribution. While much is known regarding the relationships of helicoid taxa, comparatively little is known about the evolution of the mitochondrial genome in the superfamily. We sequenced two complete mitochondrial genomes from Praticolella mexicana Perez, 2011 representing the first such data from the helicoid family Polygyridae, and used them in an evolutionary analysis of mitogenomic gene order. We found the mitochondrial genome of Praticolella mexicana to be 14,008 bp in size, possessing the typical 37 metazoan genes. Multiple alternate stop codons are used, as are incomplete stop codons. Mitogenome size and nucleotide content is consistent with other helicoid species. Our analysis of gene order suggested that Helicoidea has undergone four mitochondrial rearrangements in the past. Two rearrangements were limited to tRNA genes only, and two involved protein coding genes. PMID:27833437

  7. Description of a new species of the genus Arganiella Giusti & Pezzoli, 1980 (Mollusca, Gastropoda, Hydrobiidae from the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Ramos, M.ª A.

    2007-06-01

    Full Text Available A new species of Arganiella Giusti & Pezzoli, 1980, up to now a monotypic genus, thought to be endemic to the Italian Central Apennines, is described from the Iberian Peninsula. This new species, named Arganiella tartessica, is located in southwestern Spain, provinces of Huelva and Badajoz. In this paper, a detailed description of its morphological characters is given and new data of nervous system and ciliated areas in the cephalic region are provided.Se describe una especie ibérica de Arganiella Giusti y Pezzoli, 1980, un género que hasta ahora se consideraba monotípico y endémico de los Apeninos centrales italianos. Esta nueva especie, denominada Arganiella tartessica, ha sido localizada en el sureste español, en las provincias de Huelva y Badajoz. En este artículo se describen en detalle sus caracteres morfológicos y se presentan datos, hasta la fecha desconocidos en el género Arganiella, del sistema nervioso y de áreas ciliadas en la región cefálica.

  8. First record of Thylaeodus (Gastropoda: Vermetidae from the Equatorial Atlantic Ocean, with the description of a new species

    Directory of Open Access Journals (Sweden)

    Paula Spotorno

    2013-02-01

    Full Text Available The vermetid Thylaeodus equatorialis sp. nov. is endemic to the São Pedro and São Paulo Archipelago, located at the mid equatorial Atlantic Ocean. The species is closely related to Thylaeodus rugulosus (Monterosato, 1878, as indicated by similar shell characters, coloration of the soft parts, and feeding tube scars. However, T. equatorialis sp. nov. mainly differs from T. rugulosus in the operculum/aperture diameter ratio (~79% versus 100%, by having well developed pedal tentacles and fewer egg capsules in brooding females. In addition, the new species has the following unique characteristics: size almost twice as large (shell, tube aperture, erect feeding tube, protoconch and egg capsules as the other Atlantic species; unusual method of brooding egg capsules; radula with prominent and more numerous flanking cusps; and small pustules following the suture of the protoconch. A detailed discussion on the taxonomy and biology of vermetid Thylaeodus and allies is also presented.

  9. Gulella adami, a new species of land snail from the Ivory Coast, West Africa (Gastropoda Pulmonata: Streptaxidae)

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1994-01-01

    Gulella adami spec. nov. is described from a classical West African locality, Assini in the Ivory Coast (Côte d'Ivoire). It is most unusual in showing two superficial parietal processes, which may also be interpreted as a double angular lamella, in the aperture of the shell. The shell closely resemb

  10. Shell morphology of the freshwater snail Gundlachia ticaga (Gastropoda: Ancylidae from four sites in Ilha Grande, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Luiz Eduardo M. Lacerda

    2011-06-01

    Full Text Available The freshwater snail Gundlachia ticaga (Marcus & Marcus, 1962 is widely distributed in Brazil, but its morphology has been poorly studied. We compared the shell morphology of samples from four sites (Vila do Abraão, Vila de Provetá, Parnaioca and Praia do Sul in Ilha Grande (Angra dos Reis, state of Rio de Janeiro in order to evaluate differences within and among four populations. We used nine morphometric characters representing shell size and shape. To analyze shell morphology we considered aperture shape, sculpture of teleoconch, apex carving and position. The resulting dataset was correlated by Pearson´s linear correlation and shell differences among populations were tested using ANOVA and Discriminant Function Analysis. The results showed that there is significant variation among populations concerning shell shape and morphology. Shells from preserved localities (Praia do Sul and Parnaioca and shells from highly modified environments (Vila do Abraão and Vila de Provetá were the most similar to each other. Results from the visual assessment and from the discriminant analysis were almost identical. The shell indices are the most important variables in the differentiation of samples. The observed variation corroborates the hypothesis that G. ticaga displays phenotypic plasticity, which may lead to wrong identifications. Narrower shells with an elongate aperture could be misidentified as Ferrissia Walker, 1903 and, broader shells with a roundish aperture could be wrongly identified as Burnupia Walker, 1912. We confirmed that the absence of radial lines is not a good diagnostic character for G. ticaga. The analysis of the apical micro-sculpture and soft parts is essential for a correct identification.

  11. Costigulella primennilus spec. nov., a new minute western African terrestrial snail, with remarks on the genus Costigulella (Gastropoda Pulmonata: Streptaxidae)

    NARCIS (Netherlands)

    Winter, de A.J.

    2008-01-01

    Costigulella primennilus spec. nov. is the first representative of Costigulella reported from Cameroon. It is probably the smallest species of the family Streptaxidae known world-wide. Arguments are provided to consider Costigulella an independent radiation and genus, rather than a subgenus of Gulel

  12. Exploring species level taxonomy and species delimitation methods in the facultatively self-fertilizing land snail genus Rumina (gastropoda: pulmonata.

    Directory of Open Access Journals (Sweden)

    Vanya Prévot

    Full Text Available Delimiting species in facultatively selfing taxa is a challenging problem of which the terrestrial pulmonate snail genus Rumina is a good example. These snails have a mixed breeding system and show a high degree of shell and color variation. Three nominal species (R. decollata, R. saharica and R. paivae and two color morphs within R. decollata (dark and light are currently recognized. The present study aims at evaluating to what extent these entities reflect evolutionary diverging taxonomic units, rather than fixed polymorphisms due to sustained selfing. Therefore, a phylogenetic analysis of nuclear (ITS1, ITS2 and mitochondrial DNA (COI, CytB, 12S rDNA, 16S rDNA sequences was performed. Putative species in Rumina, inferred from the mitochondrial DNA phylogeny, were compared with those proposed on the basis of the COI gene by (1 DNA barcoding gap analysis, (2 Automatic Barcode Gap Discovery, (3 the species delimitation plug-in of the Geneious software, (4 the Genealogical Sorting Index, and (5 the General Mixed Yule Coalescent model. It is shown that these methods produce a variety of different species hypotheses and as such one may wonder to what extent species delimitation methods are really useful. With respect to Rumina, the data suggest at least seven species, one corresponding to R. saharica and six that are currently grouped under the name R. decollata. The species-level status of R. paivae is rejected.

  13. Anisospira velascorum, a new land snail from Mexico, with notes on the anatomy and histology (Mollusca, Gastropoda, Urocoptidae)

    NARCIS (Netherlands)

    Breure, A.S.H.

    1977-01-01

    During a collecting trip through southern and central Mexico (Breure, 1974) special attention has been paid to Bulimulidae and Urocoptidae. Among the material of urocoptids a new species has been found. Anisospira velascorum sp. n. (figs. 1-10, pl. 1) Description. — Shell up to 30.5 mm, 2.39 times a

  14. Intraspecific morphological and genetic variability in the European freshwater snail Radix labiata (Rossmaessler, 1835) (Gastropoda: Basommatophora: Lymnaeidae)

    NARCIS (Netherlands)

    Schniebs, K.; Glöer, P.; Vinarski, M.V.; Hundsdoerfer, A.K.

    2013-01-01

    Radix labiata is a widely distributed Palaearctic freshwater snail. This work aims to improve the knowledge of the intraspecific variability in the most important characters used for its determination. To find out which characters are really suitable to distinguish this species from other similar Ra

  15. The Japanese oyster drill Ocinebrellus inornatus (Récluz, 1851) (Mollusca, Gastropoda, Muricidae), introduced to the Limfjord, Denmark

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Faasse, Marco; Gittenberger, Adriaan

    2012-01-01

    The predatory neogastropod Ocinebrellus inornatus was first reported from Europe in W France in 1995 and has since been detected at other sites in NW and N France and The Netherlands. It is native to the North Pacific where it preys on the Pacific oyster Crassostrea gigas. Here we report on the o......The predatory neogastropod Ocinebrellus inornatus was first reported from Europe in W France in 1995 and has since been detected at other sites in NW and N France and The Netherlands. It is native to the North Pacific where it preys on the Pacific oyster Crassostrea gigas. Here we report...

  16. The occurrence, bionomics and potential impacts of the invasive freshwater snail Tarebia granifera (Lamarck, 1822) (Gastropoda: Thiaridae) in South Africa

    NARCIS (Netherlands)

    Appleton, C.C.; Forbes, A.T.; Demetriades, N.T.

    2009-01-01

    The Asian prosobranch snail Tarebia granifera was reported from South Africa (and Africa) for the first time in 1999 in northern KwaZulu-Natal though it was probably introduced sometime prior to 1996. In the 10 years since its discovery it has spread rapidly, particularly northwards, into Mpumalanga

  17. Identification of protein components of egg masses indicates parental investment in immunoprotection of offspring by Biomphalaria glabrata (gastropoda, mollusca).

    Science.gov (United States)

    Hathaway, Jennifer J M; Adema, Coen M; Stout, Barbara A; Mobarak, Charlotte D; Loker, Eric S

    2010-04-01

    The macromolecules contributed by the freshwater gastropod Biomphalaria glabrata, intermediate host of Schistosoma mansoni, to developing offspring inside egg masses are poorly known. SDS-PAGE fractionated egg mass fluids (EMF) of M line and BB02 B. glabrata were analyzed by MALDI-TOF (MS and tandem MS). A MASCOT database was assembled with EST data from B. glabrata and other molluscs to aid in sequence characterization. Of approximately 20 major EMF polypeptides, 16 were identified as defense-related, including protease inhibitors, a hemocyanin-like factor and tyrosinase (each with possible phenoloxidase activity), extracellular Cu-Zn SOD, two categories of C-type lectins, Gram-negative bacteria-binding protein (GNBP), aplysianin/achacin-like protein, as well as versions of lipopolysaccharide binding protein/bacterial permeability-increasing proteins (LBP/BPI) that differed from those previously described from hemocytes. Along with two sequences that were encoded by "unknown" ESTs, EMF also yielded a compound containing a vWF domain that is likely involved in defense and a polypeptide with homology to the Aplysia pheromone temptin. Further study of B. glabrata pheromones is warranted as these could be useful in efforts to control these schistosome-transmitting snails. Several of the EMF polypeptides were contained in the albumen gland, the organ that produces most EMF. Thus, parental investment of B. glabrata in immunoprotection of its offspring is indicated to be considerable.

  18. Experimental illumination of a forest: no effects of lights of different colours on the onset of the dawn chorus in songbirds

    NARCIS (Netherlands)

    Da Silva, Arnaud; de Jong, Maaike; van Grunsven, Roy H. A.; Visser, Marcel E.; Kempenaers, Bart; Spoelstra, Kamiel

    2017-01-01

    Light pollution is increasing exponentially, but its impact on animal behaviour is still poorly understood. For songbirds, the most repeatable finding is that artificial night lighting leads to an earlier daily onset of dawn singing. Most of these studies are, however, correlational and cannot entir

  19. Experimental illumination of a forest: no effects of lights of different colours on the onset of the dawn chorus in songbirds

    NARCIS (Netherlands)

    Silva, Da Arnaud; Jong, de Maaike; Grunsven, van R.H.A.; Visser, M.E.; Kempenaers, Bart; Spoelstra, Kamiel

    2017-01-01

    Light pollution is increasing exponentially, but its impact on
    animal behaviour is still poorly understood. For songbirds, the
    most repeatable finding is that artificial night lighting leads to
    an earlier daily onset of dawn singing. Most of these studies are,
    however, correlational

  20. Experimental illumination of a forest: no effects of lights of different colours on the onset of the dawn chorus in songbirds

    Science.gov (United States)

    de Jong, Maaike; van Grunsven, Roy H. A.; Visser, Marcel E.; Kempenaers, Bart; Spoelstra, Kamiel

    2017-01-01

    Light pollution is increasing exponentially, but its impact on animal behaviour is still poorly understood. For songbirds, the most repeatable finding is that artificial night lighting leads to an earlier daily onset of dawn singing. Most of these studies are, however, correlational and cannot entirely dissociate effects of light pollution from other effects of urbanization. In addition, there are no studies in which the effects of different light colours on singing have been tested. Here, we investigated whether the timing of dawn singing in wild songbirds is influenced by artificial light using an experimental set-up with conventional street lights. We illuminated eight previously dark forest edges with white, green, red or no light, and recorded daily onset of dawn singing during the breeding season. Based on earlier work, we predicted that onset of singing would be earlier in the lighted treatments, with the strongest effects in the early-singing species. However, we found no significant effect of the experimental night lighting (of any colour) in the 14 species for which we obtained sufficient data. Confounding effects of urbanization in previous studies may explain these results, but we also suggest that the experimental night lighting may not have been strong enough to have an effect on singing. PMID:28280562

  1. Mark Bowden and Owen Sheers present "Creation" [working title]: a new musical and poetic collaborative project for chorus, soloists and orchestra

    CERN Multimedia

    2013-01-01

    "Creation" is a new collaboration between Mark Bowden, in his role as BBC National Orchestra of Wales’ Resident Composer, and the poet and novelist Owen Sheers.   Taking Haydn's 1798 work "The Creation" as a point of departure, they plan to create a new cantata for the digital age exploring the meaning of creation in the twenty-first century. Through engagement with developments in biology and physics they plan to create a new work incorporating poetry and music that will explore the latest ideas concerning the creation of matter and the emergence of life in the universe, whilst also delving into the human side of the brilliant minds that are currently working to uncover these secrets of the universe. More information is available here. Meet them at the CERN Library (bldg. 52 1-052) on Wednesday 2 October at 4 p.m. * Coffee will be served at 3.30 p.m.*

  2. 谈合唱教学在学校素质教育中的作用%Discussing the Function of the Chorus Teaching in School Anlage Education

    Institute of Scientific and Technical Information of China (English)

    钟小威

    2000-01-01

    合唱是一种群体歌唱的多声部艺术表现形式,合唱教学包括欣赏、演唱、表演三个环节,是学校音乐教育不可缺少的一项教学内容,是对学生进行思想教育、审美教育的有效途径。本文着重就合唱教学在学校素质教育中的作用进行简要的论述。

  3. Art as tragic overcoming. An approach to the philosophical problem of the origin of the tragic choir. Commentary on the paragraphs 7 and 8 of The birth of tragedy

    Directory of Open Access Journals (Sweden)

    Oscar Quejido Alonso

    2014-07-01

    Full Text Available From Nietzsche's statement that "the tragedy born of the tragic chorus, and was originally chorus and nothing but chorus" (GT, 7, we will try to show how, since the first Nietzschean conception of tragedy, this fundamental element of his thought can be characterized, beyond next differences, as an ever transient overcoming of nihilism. Thus, by analyzing the aphorisms 7 and 8 of The Birth of Tragedy, we will show how these elements appear through Nietzsche's interpretation of the tragic chorus

  4. Mahler: Sinfonie Nr. 8 Es-Dur (Sinfonie der Tausend) / Norbert Rüdell

    Index Scriptorium Estoniae

    Rüdell, Norbert

    1995-01-01

    Uuest heliplaadist "Mahler: Sinfonie Nr. 8 Es-Dur (Sinfonie der Tausend). Estonian Boys' Choir, Brunnsbo Children's Choir, Gothenburg Opera Chorus, Royal Stockholm Philharmonic Choir, Gothenburg Symphony Chorus, Gothenburg Opera Chorus, Gothenburg Symphony Orchestra, Neeme Järvi. BIS/Disco-Center CD 700 (WD:72'18")

  5. Aplicaciones biotecnológicas del gen "afp" (Antifungical Protein) de "Aspergillus giganteus" para la protección de plantas frente a infección por patógenos

    OpenAIRE

    Moreno Gonçalves, Ana Beatriz

    2006-01-01

    Las plantas están constantemente sometidas a estreses ambientales y los hongos son sus principales patógenos. Actualmente, el control de las enfermedades que causan se realiza utilizando compuestos químicos, generando impacto en el medio ambiente. Una alternativa es la obtención de plantas transgénicas resistentes. En un principio, la mayoría de los transgenes provenían de las propias plantas (genes involucrados en las respuestas de densa). Actualmente, y dada su reducida efectividad, se está...

  6. Study on the Effects of Diverting Water into Upper Burnt Pocket, Navigation Pool Number 18, Illinois and A Field Test of the Regression Simulation Model Previously Developed on Navigation Pool Number 8.

    Science.gov (United States)

    1981-03-01

    Ephemeroptera, C = Odonata , E = Trichoptera, F = Coleoptera, G = Diptera, H = Gastropoda, I = Pelecypoda ....... ................... ... 53 Figure 5. Biomass (g...13, 1979. A = Oiigochaeta, B = Hirudinea, C = Ephemeroptera, D = Odonata , E = Trichoptera, F = Coeleoptera, G = Diptera, H = Gastropoda, I = Pelecypoda...Area, Navigation Pool No. 18, Illinois, on August 5, 1980. A = Oligochaeta, B = Hirudinea, C = Ephemeroptera, D = Odonata , E = Trichoptera, F

  7. Determination of the variability of both hydrophilic and lipophilic toxins in endemic wild bivalves and carnivorous gastropods from the southern part of Chile.

    Science.gov (United States)

    Zamorano, Ruben; Marín, Michelle; Cabrera, Fabiola; Figueroa, Diego; Contreras, Cristóbal; Barriga, Andrés; Lagos, Néstor; García, Carlos

    2013-01-01

    The aim of this study was to analyse and determine the composition of paralytic shellfish poisoning (PSP) toxins and lipophilic toxins in the Region of Aysén, Chile, in wild endemic mussels (Mytilus chilensis, Venus antiqua, Aulacomya ater, Choromytilus chorus, Tagelus dombeii and Gari solida) and in two endemic carnivorous molluscs species (Concholepas concholepas and Argobuccinum ranelliforme). PSP-toxin contents were determined by using HPLC with fluorescence detection, while lipophilic toxins were determined by using LC-MS/MS. Mean concentrations for the total of PSP toxins were in the range 55-2505 μg saxitoxin-equivalent/100 g. The two most contaminated samples for PSP toxicity were bivalve Gari solida and carnivorous Argobuccinum ranelliforme with 2505 ± 101 and 1850 ± 137 μg saxitoxin-equivalent/100 g, respectively (p < 0.05). The lipophilic toxins identified were okadaic acid, dinophysistoxin-1 (DTX-1), azaspiracid-1 (AZA-1), pectenotoxin-2 (PTX-2) and yessotoxins (YTX). All analysed molluscs contained lipophilic toxins at levels ranging from 56 ± 4.8 to 156.1 ± 8.2 μg of okadaic acid-equivalent/kg shellfish together with YTX at levels ranging from 1.0 ± 0.1 to 18 ± 0.9 μg of YTX-equivalent/kg shellfish and AZA at levels ranging from 3.6 ± 0.2 to 31 ± 2.1 μg of AZA-equivalent/kg shellfish. Furthermore, different bivalves and gastropods differ in their capacity of retention of lipophilic toxins, as shown by the determination of their respective lipophilic toxins levels. In all the evaluated species, the presence of lipophilic toxins associated with biotransformation in molluscs and carnivorous gastropods was not identified, in contrast to the identification of PSP toxins, where the profiles identified in the different species are directly related to biotransformation processes. Thus, this study provides evidence that the concentration of toxins in the food intake of the evaluated species (Bivalvia and Gastropoda class) determines the degree of

  8. Ontogenetic changes in feeding and food preferences of the dog conch Laevistrombus canarium Linnaeus 1758 (Mollusca: Gastropoda) from Merambong shoal, Malaysia

    Science.gov (United States)

    Husna, Wan Nurul Wan Hassan; Mazlan, Abd Ghaffar; Cob, Zaidi Che

    2016-10-01

    Laevistrombus canarium is one of the marine gastropod mollusks that have high commercial value, particularly in the aquaculture sector in Malaysia. This study was conducted to determine the feeding and food items of L. canarium at different ontogenetic stages (juveniles, sub-adults and adults) from Merambong shoals, Malaysia. Field observations on feeding activity were conducted, followed by detailed laboratory analysis on the stomach content. Five-minutes observations on randomly selected individuals were conducted at the field sampling site and their feeding activities were recorded with reference to age stage. Various shell sizes from each ontogenetic stage were randomly collected and quickly anaesthetized with ice and preserved in 10% formalin before being transported to the laboratory for stomach content analyses. Field observations showed that L. canarium mainly grazed on epiphytes occurring on seagrass (46.67%), followed by sediment surface (40%) and epiphytes occurring on macroalgae (13.33%). Stomach content analyses showed a significant difference (P Food items found in the conch stomach include diatoms, detritus, foraminifera, seagrass and macroalgae fragments, sand particles and shell fragments. The Index of Relative Importance (%IRI) indicates three main types of food dominated the three ontogenetic stages namely diatoms, sand particles and detritus. However, no significant difference (P >0.05) was detected between the three main food items (diatoms, sand particles and detritus) among the ontogenetic stages. Therefore, feeding activity revealed the role of the dog conch in the marine food network. While, classification of the types of food consumed by L. canarium through stomach content analysis determines the particular position of the gastropod in the food chain. Further studies are needed to provide a better insight between trophic relationships of L. canarium with marine ecosystem.

  9. On a collection of Peruvian Neniinae (Mollusca: Gastropoda: Clausiliidae), with a check-list and a provisional key to all the Peruvian species known

    NARCIS (Netherlands)

    Loosjes, F.E.; Loosjes-van Bemmel, A.C.W.

    1984-01-01

    An annotated list is given of all Neniinae collected in 1975 by Dr. A. S. H. Breure in Peru. The localities that have been visited are also listed, together with the Neniinae collected there. Pseudogracilinenia gen. nov. is described for P. huallagana (Pilsbry, 1949) (type-species) and P.jolyi (O. B

  10. Threatened freshwater and terrestrial molluscs (Mollusca, Gastropoda et Bivalvia of Santa Catarina State, Southern Brazil: check list and evaluation of regional threats

    Directory of Open Access Journals (Sweden)

    2011-06-01

    Full Text Available A total of nineteen continental native mollusc species are confirmed for the Santa Catarina State (SC(organized in ten Genera and seven Families, one aquatic Prosobranchia/Caenogastropoda (Ampullariidae,six Pulmonata terrestrial gastropods (one Ellobiidae, three Megalobulimidae and two micro-snails –Charopidae and Streptaxidae and twelve freshwater mussels (eight Mycetopodidae and four Hyriidae. Thesespecies are designated by the International Union for Conservation of the Nature – IUCN as follows: seven as"Vulnerable", six "In Danger" and six “Without Category Established”. The general regional threats that thesespecies are subjected to are briefly analyzed.

  11. Registro de Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda no Brasil: caramujo hospedeiro intermediário da angiostrongilíase

    Directory of Open Access Journals (Sweden)

    Horácio Manuel Santana Teles

    1997-06-01

    Full Text Available A introdução de Achatina fulica é assinalada em Itariri, SP, Brasil. Essa espécie de caramujo terrestre foi importada para cultivo, visando à comercialização para consumo humano como "escargot". O encontro de exemplares em vida livre mostra a dispersão de A. fulica e, conseqüentemente, o risco de transmissão de Angiostrongylus cantonensis, nematóide parasita do homem e de outros vertebrados. Além disso, o caramujo é uma praga importante da agricultura.

  12. Serina Gredler (Gastropoda, Stylommatophora: Enidae), the continuous-peristomed mountain snails endemic to the eastern slope of the Qinghai-Xizang Plateau.

    Science.gov (United States)

    Wu, Min; Xu, Qin

    2013-01-01

    In this paper we initiate a taxonomic review of the genus Serina Gredler, endemic to the eastern slope of the Qinghai-Xizang Plateau, namely S Gansu, SW Sichuan, SE Xizang Autonomous Region and N Yunnan of China. We describe the genital anatomy for some species and the shell morphology for all known species: Serina belae (Hilber), S. cathaica Gredler, S. egressa Sturany, S. prostoma (Ancey), S. ser Gredler, S. subser Gredler, S. soluta (Möllendorff) and S. vincentii (Gredler). Based on the re-evaluation of both shell and genitalian differentiations we prefer to classify the taxon egressa as a separate species rather than a subspecies of S. ser. In our study we come to the conclusion that S. soluta inflata Yen and S. soluta stenochila (Möllendorff) should be regarded as synonyms of S. soluta due to the insufficient differentiation among them. Buliminus (Holcauchen) tubios Annandale, Bulimus prostoma leucochila Ancey and Serina deqenensis Chen, Zhou and Luo were conspecific with Serina prostoma and that Serina sobrina (Preston) was conspecific with Clausiliopsis szechenyi (Böttger). We propose a new species Serina denticulata n. sp. from the Southern Gansu Plateau. Furthermore we discuss the phylogenetic relationship among the genera Serina, Clausiliopsis Möllendorff, Pupopsis Gredler, and Pupinidius Mö1lendorff based on the morphological data from twelve relevant species.

  13. A new record of Morula anaxares with a description of the radula of three other species from Goa, Central West Coast of India (Gastropoda: Muricidae)

    Digital Repository Service at National Institute of Oceanography (India)

    Kumbhar, J.V.; Rivonker, C.U.

    shell morphology, sculpture, micro-structure, operculum, radula and anatomical characters. However, studies along Indian coasts (Rao and Rao, 1993; Rajagopal et al., 1998; Rao, 2003) are meagre and based primarily on shell morphology, operculum... structure and meristic counts. Further, these studies lack details of radular structure, an important tool used in muricid systematics. Radular characters have also been widely used in diagnosis, even though Jyoti V. Kumbhar1, Chandrashekher U. Rivonker2...

  14. Evaluation of the cholinomimetic actions of trimethylsulfonium, a compound present in the midgut gland of the sea hare Aplysia brasiliana (Gastropoda, Opisthobranchia

    Directory of Open Access Journals (Sweden)

    C.M. Kerchove

    2002-04-01

    Full Text Available Trimethylsulfonium, a compound present in the midgut gland of the sea hare Aplysia brasiliana, negatively modulates vagal response, indicating a probable ability to inhibit cholinergic responses. In the present study, the pharmacological profile of trimethylsulfonium was characterized on muscarinic and nicotinic acetylcholine receptors. In rat jejunum the contractile response induced by trimethylsulfonium (pD2 = 2.46 ± 0.12 and maximal response = 2.14 ± 0.32 g was not antagonized competitively by atropine. The maximal response (Emax to trimethylsulfonium was diminished in the presence of increasing doses of atropine (P<0.05, suggesting that trimethylsulfonium-induced contraction was not related to muscarinic stimulation, but might be caused by acetylcholine release due to presynaptic stimulation. Trimethylsulfonium displaced [³H]-quinuclidinyl benzilate from rat cortex membranes with a low affinity (Ki = 0.5 mM. Furthermore, it caused contraction of frog rectus abdominis muscles (pD2 = 2.70 ± 0.06 and Emax = 4.16 ± 0.9 g, which was competitively antagonized by d-tubocurarine (1, 3 or 10 µM with a pA2 of 5.79, suggesting a positive interaction with nicotinic receptors. In fact, trimethylsulfonium displaced [³H]-nicotine from rat diaphragm muscle membranes with a Ki of 27.1 µM. These results suggest that trimethylsulfonium acts as an agonist on nicotinic receptors, and thus contracts frog skeletal rectus abdominis muscle and rat jejunum smooth muscle via stimulation of postjunctional and neuronal prejunctional nicotinic cholinoreceptors, respectively.

  15. Environmental Epidemiology of Intestinal Schistosomiasis in Uganda: Population Dynamics of Biomphalaria (Gastropoda: Planorbidae in Lake Albert and Lake Victoria with Observations on Natural Infections with Digenetic Trematodes

    Directory of Open Access Journals (Sweden)

    Candia Rowel

    2015-01-01

    Full Text Available This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were classified as either human infective (Schistosoma mansoni or nonhuman infective. The population dynamics of Biomphalaria differed by location and by lake and had positive relationship with pH (P<0.001 in both lakes and negative relationship with conductivity (P=0.04 in Lake Albert. Of the Biomphalaria collected in Lake Albert N=6,183, 8.9% were infected with digenetic trematodes of which 15.8% were shedding S. mansoni cercariae and 84.2% with nonhuman infective cercariae. In Lake Victoria, 2.1% of collected Biomphalaria  N=13,172 were infected with digenetic trematodes with 13.9% shedding S. mansoni cercariae, 85.7% shedding nonhuman infective cercariae, and 0.4% of infected snails shedding both types of cercariae. Upon morphological identification, species of Biomphalaria infected included B. sudanica, B. pfeifferi, and B. stanleyi in Lake Albert and B. sudanica, B. pfeifferi, and B. choanomphala in Lake Victoria. The study found the physicochemical factors that influenced Biomphalaria population and infections. The number and extent of snails shedding S. mansoni cercariae illustrate the high risk of transmission within these lake settings. For better control of this disease, greater effort should be placed on reducing environmental contamination by improvement of local water sanitation and hygiene.

  16. Environmental Epidemiology of Intestinal Schistosomiasis in Uganda: Population Dynamics of Biomphalaria (Gastropoda: Planorbidae) in Lake Albert and Lake Victoria with Observations on Natural Infections with Digenetic Trematodes

    Science.gov (United States)

    Rowel, Candia; Fred, Besigye; Sousa-Figueiredo, Jose C.; Kabatereine, Narcis B.; Stothard, J. Russell

    2015-01-01

    This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were classified as either human infective (Schistosoma mansoni) or nonhuman infective. The population dynamics of Biomphalaria differed by location and by lake and had positive relationship with pH (P < 0.001) in both lakes and negative relationship with conductivity (P = 0.04) in Lake Albert. Of the Biomphalaria collected in Lake Albert (N = 6,183), 8.9% were infected with digenetic trematodes of which 15.8% were shedding S. mansoni cercariae and 84.2% with nonhuman infective cercariae. In Lake Victoria, 2.1% of collected Biomphalaria  (N = 13,172) were infected with digenetic trematodes with 13.9% shedding S. mansoni cercariae, 85.7% shedding nonhuman infective cercariae, and 0.4% of infected snails shedding both types of cercariae. Upon morphological identification, species of Biomphalaria infected included B. sudanica, B. pfeifferi, and B. stanleyi in Lake Albert and B. sudanica, B. pfeifferi, and B. choanomphala in Lake Victoria. The study found the physicochemical factors that influenced Biomphalaria population and infections. The number and extent of snails shedding S. mansoni cercariae illustrate the high risk of transmission within these lake settings. For better control of this disease, greater effort should be placed on reducing environmental contamination by improvement of local water sanitation and hygiene. PMID:25705680

  17. Sclerochronology - a highly versatile tool for mariculture and reconstruction of life history traits of the queen conch, textit{Strombus gigas} (Gastropoda)

    Science.gov (United States)

    Radermacher, Pascal; Schöne, Bernd R.; Gischler, Eberhard; Oschmann, Wolfgang; Thébault, Julien; Fiebig, Jens

    2010-05-01

    The shell of the queen conch Strombus gigas provides a rapidly growing palaeoenvironmental proxy archive, allowing the detailed reconstruction of important life-history traits such as ontogeny, growth rate and growth seasonality. In this study, modern sclerochronological methods are used to cross-date the palaeotemperatures derived from the shell with local sea surface temperature (SST) records. The growth history of the shell suggests a bimodal seasonality in growth, with the growing season confined to the interval between April and November. In Glovers Reef, offshore Belize, the queen conch accreted shell carbonate at rates of up to 6 mm day-1 during the spring (April-June) and autumn (September-November). However a reduced period of growth occurred during the mid-summer months (July-August). The shell growth patterns indicate a positive response to annual seasonality with regards to precipitation. It seems likely that when precipitation levels are high, food availability is increased as the result of nutrient input to the ecosystem in correspondence with an increase in coastal runoff. Slow growth rates occur when precipitation, and as a consequence riverine runoff, is low. The SST however appears to influence growth only on a secondary level. Despite the bimodal growing season and the winter cessation in growth, the growth rates reconstructed here from two S. gigas shells are among the fastest yet reported for this species. The S. gigas specimens from Belize reached their final shell height (of 22.7 and 23.5 cm in distance between the apex and the siphonal notch) at the transition to adulthood in just 2 years. The extremely rapid growth as observed in this species permits detailed, high-resolution reconstructions of life-history traits where sub-daily resolutions can be achieved with ease. The potential for future studies has yet to be further explored. Queen conch sclerochronology provides an opportunity to recover extremely high-resolution palaeotemperature records, which could be used to improve numeric climate models, where the shells essentially function as mineralized buoys. The shell recorder may also help to reveal changes in biogeochemical dynamics in benthic ecosystems on intra-seasonal timescales in the fossil record. Furthermore, sclerochronology provides a rapid, effective and highly versatile investigative strategy when compared to time- and cost-consuming fieldwork for improving fisheries management and maricultural pursuits.

  18. Coat of many colours—DNA reveals polymorphism of mantle patterns and colouration in Caribbean Cyphoma Röding, 1798 (Gastropoda, Ovulidae

    Directory of Open Access Journals (Sweden)

    Bastian T. Reijnen

    2017-03-01

    Full Text Available The iconic gastropod genus Cyphoma is commonly observed in the Caribbean, where it lives in association with various octocorallian hosts. Each species in the genus Cyphoma has a unique, characteristic mantle pattern and colouration, which separates the valid taxa. Because of its abundance and recognisability Cyphoma gibbosum has been used as a model organism in several studies concerning allelochemicals, reef degradation, and physical defence mechanisms. Molecular analyses based on four molecular markers (COI, 16S, H3 and 28S for three Cyphoma species (C. gibbosum, C. mcgintyi, C. signatum and an unidentified black morph, collected from three localities in the Caribbean, show that they represent morphological varieties of a single, genetically homogeneous species. This outcome is in agreement with previous anatomical studies. As a result C. mcgintyi and C. signatum are synonymised with C. gibbosum, which is a key result for future work using C. gibbosum as a model organism. The striking morphological differences in mantle pattern and colouration are hypothesised to be the result of one of three possible scenarios: rapid divergence, supergenes (including balanced polymorphism, or incipient speciation.

  19. Duration of pairing and use of allosperm in Biomphalaria glabrata (Gastropoda: Planorbidae Duração do acasalamento e uso do aloesperma em Biomphalaria glabrata (Gastropode: Planorbidae

    Directory of Open Access Journals (Sweden)

    Marc Vianey-Liaud

    1989-03-01

    Full Text Available Virgin homozygous black pigmented and albino Biomphalaria glabrata are paired during a period varying from 1 to 20 days. The rate of cross-fertilized parents is statistically similar for the various lengths of pairing. As a whole, nearly 80% of the albino snails produce a pigmented progeny. This production begins as soon as the snails are mated and continues after their separation. To measure the actual use of the allosperm, its use during the postmating period must be added to the length of mating. So, it appears that the real use of the allosperm is statistically constant (mean slightly inferior to 8 weeks and not related to the length of the previous pairing.Espécimes virgens de Biomphalaria glabrata (um melâncio e um albino são acasalados durante um período variável de 1 a 20 dias. A proporção de espécimes parentais albinos fecundados por cruzamento é semelhante estatisticamente para os diversos períodos de acasalamento. Em conjunto, cerca de 80% dos albinos produziram descendência pigmentada. Essa produção começa assim que os moluscos são acasalados e continua depois que são separados. Para medir a utilização real do aloesperma, sua utilização durante o período de pós-acasalamento. Parece, assim, que a utilização real do aloesperma é estatisticamente constante (média ligeiramente inferior a oito semanas e não relacionada a duração do acasalamento anterior.

  20. Assessing the effects of fluoxetine on Physa acuta (Gastropoda, Pulmonata) and Chironomus riparius (Insecta, Diptera) using a two-species water-sediment test

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Argueello, Paloma [Laboratory for Ecotoxicology, Department of the Environment, INIA, Crta, A Coruna km 7, 28040 Madrid (Spain)], E-mail: arguello@inia.es; Fernandez, Carlos; Tarazona, Jose V. [Laboratory for Ecotoxicology, Department of the Environment, INIA, Crta, A Coruna km 7, 28040 Madrid (Spain)

    2009-03-01

    Fluoxetine has been tested in a two-species water-sediment system, which allowed a two-generation study with Chironomus riparius and a partial life-cycle with the freshwater snail Physa acuta to be performed at the same time. The design considered the continuous application of fluoxetine to overlaying water for nominal concentrations of 31.25, 62.5, 125 and 250 {mu}g/L. A fifth treatment (87.5 {mu}g/L) level consisted of pulse applications once a week. Measures of water and sediment concentrations were determined once a week and at the end of experiment (day 44), respectively. The fate study demonstrated that water dissipation can be explained by partitioning of fluoxetine to sediment. At the end of experiment, the percentage of detected fluoxetine was up to 10-fold higher in sediment than in overlaying water. The employed two-species test allowed distinguishing, in the same exposure conditions, effects due to waterborne exposure together ingestion at the sediment surface (freshwater grazing snail P. acuta) and exposure by burrowing activities (sediment-dwelling insect larvae C. riparius). The effect assessment showed a stimulation of P. acuta reproduction at lower concentrations (31.25 and 62.5 {mu}g/L), while the opposite effect was observed at the highest treatment (250 {mu}g/L). Additional studies should be conducted to establish if the statistically significant differences observed in F0 sex ratio at the 62.5 {mu}g/L and F1 adult emergence at 31.25 {mu}g/L of C. riparius have a toxicological significance. This study showed that fluoxetine can affect reproduction of freshwater molluscs. The results of the present study may contribute to knowledge on ecotoxicology of pharmaceuticals, about which little data is available. The possible consequences and implications for targeting the environmental risk assessment of fluoxetine are discussed.