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Sample records for species chlorophyta chlorophyceae

  1. Comparative analyses of chloroplast genome data representing nine green algae in Sphaeropleales (Chlorophyceae, Chlorophyta

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    Karolina Fučíková

    2016-06-01

    Full Text Available The chloroplast genomes of green algae are highly variable in their architecture. In this article we summarize gene content across newly obtained and published chloroplast genomes in Chlorophyceae, including new data from nine of species in Sphaeropleales (Chlorophyceae, Chlorophyta. We present genome architecture information, including genome synteny analysis across two groups of species. Also, we provide a phylogenetic tree obtained from analysis of gene order data for species in Chlorophyceae with fully sequenced chloroplast genomes. Further analyses and interpretation of the data can be found in “Chloroplast phylogenomic data from the green algal order Sphaeropleales (Chlorophyceae, Chlorophyta reveal complex patterns of sequence evolution” (Fučíková et al., In review [1].

  2. Accurate and robust phylogeny estimation based on profile distances: a study of the Chlorophyceae (Chlorophyta

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    Rahmann Sven

    2004-06-01

    Full Text Available Abstract Background In phylogenetic analysis we face the problem that several subclade topologies are known or easily inferred and well supported by bootstrap analysis, but basal branching patterns cannot be unambiguously estimated by the usual methods (maximum parsimony (MP, neighbor-joining (NJ, or maximum likelihood (ML, nor are they well supported. We represent each subclade by a sequence profile and estimate evolutionary distances between profiles to obtain a matrix of distances between subclades. Results Our estimator of profile distances generalizes the maximum likelihood estimator of sequence distances. The basal branching pattern can be estimated by any distance-based method, such as neighbor-joining. Our method (profile neighbor-joining, PNJ then inherits the accuracy and robustness of profiles and the time efficiency of neighbor-joining. Conclusions Phylogenetic analysis of Chlorophyceae with traditional methods (MP, NJ, ML and MrBayes reveals seven well supported subclades, but the methods disagree on the basal branching pattern. The tree reconstructed by our method is better supported and can be confirmed by known morphological characters. Moreover the accuracy is significantly improved as shown by parametric bootstrap.

  3. Rare Pediastrum species (Chlorophyceae from Polish coastal lakes

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    Joanna Kowalska

    2011-01-01

    Full Text Available An account is given of the occurrence of Pediastrum (Chlorophyceae, Sphaeropleales in five eutrophic coastal lakes (Jamno, Bukowo, Gardno, Łebsko and Sarbsko in northern Poland, together with morphological data of the species and more detailed taxonomic and ecological information for three taxa which appear to be rare world wide. These are P. musterii, P. orientale and P. alternans; the first is recorded for the first time from central Europe. P. orientale and P. alternans show considerable morphological variability under different environmental conditions, indicating the need for further studies. The studied lakes seem to be especially favourable for Pediastrum, with a total of eight species (15 taxa in the phytoplankton noted during the summer. However, the relative frequency of the genus in the overall algal communities was low. The most frequent species were P. boryanum, P. kawraiskyi and P. duplex and these were accompanied by cyanobacteria, coccal green algae (Chlorophyceae, Chlorococcales and diatoms (Bacillariophyceae. All the Pediastrum taxa were documented using LM and SEM.

  4. Cryptic diversity within the genus .i.Pseudomuriella./i. Hanagata (Chlorophyta, Chlorophyceae, Sphaeropleales) assessed using four Barcode markers

    Czech Academy of Sciences Publication Activity Database

    Fučíková, K.; Rada, J.C.; Lukešová, Alena; Lewis, L.A.

    2011-01-01

    Roč. 93, 1/2 (2011), s. 29-46 ISSN 0029-5035 Grant - others:National Science Foundation(US) DEB-0529737; National Science Foundation(US) ATA1-4KH47C Institutional research plan: CEZ:AV0Z60660521 Keywords : barcoding * coccoid * cryptic species Subject RIV: EH - Ecology, Behaviour Impact factor: 0.615, year: 2011

  5. Surveying Caulerpa (Chlorophyta species along the shores of the eastern Mediterranean

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    S. UKABI

    2012-02-01

    Full Text Available Caulerpa (Chlorophyta species inhabiting intertidal and shallow subtidal areas along the Israeli Mediterranean shores were surveyed (i.e. presence/absence on a seasonal basis from 2007-2009. We recorded the presence of three speciesC. prolifera, C. mexicana, and C. scalpelliformis. These species were noticeable in autumn and inconspicuous during winter, thus, revealing seasonality and population dynamics. There were no indications of well-known invasive species such as Caulerpa racemosa var.cylindracea and Caulerpa taxifolia. This study is the first of a kind that assesses the geographical distribution and seasonality of the genus Caulerpa along the Israeli shores.

  6. Delineating a New Heterothallic Species of Volvox (Volvocaceae, Chlorophyceae Using New Strains of "Volvox africanus".

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    Hisayoshi Nozaki

    Full Text Available The volvocine algae represent an excellent model lineage in which to study evolution of female and male genders based on comparative analyses of related species. Among these species, Volvox carteri has been extensively studied as a model of an oogamous and complex organism. However, it may have unique derived features that are not present in other species of Volvox. Therefore, information regarding the characteristics of sexual reproduction of other species of Volvox is also important. In 1971, Starr studied four types of sexuality in several global strains identified as Volvox africanus; however, further taxonomic studies of these strains have been lacking, and strains of three of the four sexual types are not available. Here, we studied the morphology, sexual reproduction, and taxonomy of two V. africanus-like species isolated recently from Lake Biwa, Japan. These two species were very similar to two sexual types described by Starr in 1971: one producing dioecious sexual spheroids in heterothallic strains and the other forming both male spheroids and monoecious spheroids in a single strain. The former species produced zygotes with a reticulate cell wall, whereas a smooth zygote wall was observed in the latter species as in V. africanus previously reported from various localities around the world. Our multigene phylogenetic analysis demonstrated that these are sister species to each other. However, the presence of a compensatory base change in the most conserved region of the secondary structure of nuclear ribosomal DNA internal transcribed spacer-2, hybrid inviability demonstrated by intercrossing experiments, and morphological differences in the density of abutment between the gelatinous material of adjacent cells (individual sheaths in the spheroid supported the recognition of the two species, V. africanus having a smooth zygote wall and V. reticuliferus Nozaki sp. nov. having a reticulate zygote wall.

  7. A NEW SPECIES OF VOLVOX SECT. MERRILLOSPHAERA (VOLVOCACEAE, CHLOROPHYCEAE) FROM TEXAS1.

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    Nozaki, Hisayoshi; Coleman, Annette W

    2011-06-01

    Smith (1944) divided the familiar genus Volvox L. into four sections, placing seven species that lacked cytoplasmic bridges between adult cells in the section Merrillosphaera. Herein, we describe a new member of the section Merrillosphaera originating from Texas (USA): Volvox ovalis Pocock ex Nozaki et A. W. Coleman sp. nov. Asexual spheroids of V. ovalis are ovoid or elliptical, with a monolayer of 1,000-2,000 somatic cells that are not linked by cytoplasmic bridges, an expanded anterior region, and 8-12 gonidia in the posterior region. Visibly asymmetric cleavage divisions do not occur in V. ovalis embryos as they do Volvox carteri F. Stein, Volvox obversus (W. Shaw) Printz, and Volvox africanus G. S. West, so the gonidia of the next generation are not yet recognizable in V. ovalis embryos prior to inversion. Molecular phylogenetic analyses of the five chloroplast genes and the internal transcribed spacer (ITS) regions of nuclear rDNA indicated that V. ovalis is closely related to Volvox spermatosphaera Powers (Powers 1908, as "spermatosphara") and/or Volvox tertius Art. Mey.; however, V. ovalis can be distinguished from V. spermatosphaera by its larger gonidia, and from V. tertius by visible differences in gonidial chloroplast morphology. © 2011 Phycological Society of America.

  8. Genealogy in Microspora (Chlorophyceae)

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    Jong, de Y.S.D.M.; Lokhorst, G.M.; Kruijer, J.D.

    2000-01-01

    The genealogical relationships in the green algal genus Microspora (Chlorophyceae) are determined by phylogenetic analysis based on 15 ecological, morphological and reproductive characters. It is found that the traditional defining characters like cell shape and distinctness of the H-shaped pieces

  9. DESCRIPTION OF TWO NEW MONOECIOUS SPECIES OF VOLVOX SECT. VOLVOX (VOLVOCACEAE, CHLOROPHYCEAE), BASED ON COMPARATIVE MORPHOLOGY AND MOLECULAR PHYLOGENY OF CULTURED MATERIAL(1).

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    Isaka, Nanako; Kawai-Toyooka, Hiroko; Matsuzaki, Ryo; Nakada, Takashi; Nozaki, Hisayoshi

    2012-06-01

    Species of Volvox sect. Volvox (Volvocaceae, Chlorophyceae) are unique because they have thick cytoplasmic bridges between somatic cells and spiny-walled zygotes. This section is taxonomically important because the genus Volvox is polyphyletic. However, taxonomic studies of species in Volvox sect. Volvox have not been carried out on cultured material. Here, we performed a taxonomic study of monoecious species of Volvox sect. Volvox based on the comparative morphology and molecular phylogeny of chloroplast genes and the internal transcribed spacer (ITS) regions of nuclear rDNA using various strains originating from Japan and two preserved strains from the USA. The strains were clearly divided into four species, V. globator L., V. barberi W. Shaw, V. kirkiorum sp. nov., and V. ferrisii sp. nov., on the basis of differences in numbers of zygotes (eggs) in the sexual spheroids, form of zygote wall, and somatic cell shape. Sequences for ITS of nuclear rDNA resolved that the two new species have phylogenetic positions separated from V. globator, V. barberi, V. capensis F. Rich et Pocock, and V. rousseletii G. S. West UTEX 1862 within Volvox sect. Volvox. © 2012 Phycological Society of America.

  10. Taxonomic studies on the marine and brackish-water species of Ulothrix (Ulotricales, Chlorophyceae) in western Europe

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    Lokhorst, G.M.

    1978-01-01

    In this fourth report on the taxonomy of Ulothrix Kützing a new classification of the marine and brackish-water species in western Europe is proposed. Comparative studies on field collections, uni-algal cultures, herbarium collections and sections prepared for electron microscopy lead to the

  11. Morphological study of three species of Polyphysaceae (Chlorophyta from southern seashores of Iran (Persian Gulf

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    Jelveh Sohrabipour

    2016-09-01

    Full Text Available Members of Polyphysaceae (Acetabulariaceae are very beautiful and attractive unicellular plants which grow on coral reefs of the intertidal regions especially in tropical oceans and seas. In this study morphological features of some collected and identified species of the family from the Iranian seashores of Persian Gulf has been reported. Parvocaulis parvulus, Acetabularia caliculus and Parvocaulis clavatus are three identified species in the studied area which mainly collected from Hormozgan province seashores. Cap forms, number and form of rays, form of corona, hair scars and size of vegetative and reproductive parts of each species were studied after decalcification and results were presented in this paper.

  12. Morphological study of three species of Polyphysaceae (Chlorophyta) from southern seashores of Iran (Persian Gulf)

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    Jelveh Sohrabipour; Reza Rabiei

    2016-01-01

    Members of Polyphysaceae (Acetabulariaceae) are very beautiful and attractive unicellular plants which grow on coral reefs of the intertidal regions especially in tropical oceans and seas. In this study morphological features of some collected and identified species of the family from the Iranian seashores of Persian Gulf has been reported. Parvocaulis parvulus, Acetabularia caliculus and Parvocaulis clavatus are three identified species in the studied area which mainly collected from Hormozg...

  13. Culturing requirements and commercial quality of four different species of Ulva (Ulvales, chlorophyta)

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    Cremades Ugarte, Javier; Casais, Eduardo; Couce, A.; Alamrousi, A; Pintado Valverde, José; Oca Baradad, Joan; Masaló Llorà, Ingrid; Jiménez de Ridder, Patrícia

    2016-01-01

    The commercial production of Ulva spp. by aquaculture is gaining in importance due both to the qualitative and quantitative increase in the use of the harvested biomass and its new applications in inland IMTA techniques. However, very little is known about the specific culturing requirements and commercial quality of the different species of Ulva. The aim of this work is to try from this point of view four Ulva species that could be grown in southern Europe: U. australis, U. fasciata...

  14. Taxonomy of Nephroselmis viridis sp. nov. (Nephroselmidophyceae, Chlorophyta), a sister marine species to freshwater N. olivacea.

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    Yamaguchi, Haruyo; Suda, Shoichiro; Nakayama, Takeshi; Pienaar, Richard N; Chihara, Mitsuo; Inouye, Isao

    2011-01-01

    The genus Nephroselmis (Nephroselmidophyceae), which had been placed in the Prasinophyceae, is one of the primitive green flagellates that are important to our understanding of the early evolution of green plants. We studied a new species of Nephroselmis isolated from Japan, Fiji and South Africa. This species has been known for a long time as undescribed species 'N. viridis.' N. viridis possesses some ultrastructural characters shared with only the freshwater type species N. olivacea, including a disc-like structure beneath the pyrenoid and bipolar spiny body scales with 1-5-8-5-1 spines. Molecular phylogenetic analysis based on 18S rDNA also supports a sister relationship between N. viridis and N. olivacea. However, N. viridis is distinguishable from N. olivacea by the shape of its starch sheath, its scales, its pigment composition and its habitat. In this paper, we designate the formal description of N. viridis sp. nov. We also describe variability in the 18S rDNA introns of various N. viridis strains. This detailed study of N. viridis provides some insights into the evolution of Nephroselmis.

  15. TEMPERATURE RESPONSES AND DISTRIBUTION OF AUSTRALIAN SPECIES OF CLADOPHORA (CLADOPHORALES, CHLOROPHYTA)

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    CAMBRIDGE, ML; BREEMAN, AM; VANDENHOEK, C

    Temperature ranges for survival, growth and sporulation of isolates of 11 Cladophora species from Australia, as well as one isolate from Japan, were tested in constant temperature conditions from 0 to 35-degrees-C at 5-degrees-C intervals over 3 months. These ranges were compared with those

  16. Visualization of DNA-containing structurs in various species of Chlorophyta, Rhodophyta and Cyanophyta using SYBR green I dye

    Czech Academy of Sciences Publication Activity Database

    Vítová, Milada; Hendrychová, Jana; Cepák, Vladislav; Zachleder, Vilém

    2005-01-01

    Roč. 50, č. 4 (2005), s. 333-340 ISSN 0015-5632 R&D Projects: GA ČR GA204/02/1438; GA ČR GA204/03/1113; GA AV ČR KJB5020305 Institutional research plan: CEZ:AV0Z5020903; CEZ:AV0Z60050516 Keywords : dna-containing * chlorophyta * rhodophyta Subject RIV: EE - Microbiology, Virology Impact factor: 0.918, year: 2005

  17. TEMPERATURE RESPONSES AND EVOLUTION OF THERMAL TRAITS IN CLADOPHOROPSIS-MEMBRANACEA (SIPHONOCLADALES, CHLOROPHYTA)

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    PAKKER, H; VANREINE, WFP; BREEMAN, AM

    1994-01-01

    Temperature tolerances and relative growth rates were determined for different isolates of the tropical to warm temperate seaweed species Cladophoropsis membranacea (C. Agardh) Boergesen (Siphonocladales, Chlorophyta) and some related taxa. Most isolates of C. membranacea survived undamaged at 18

  18. TRACKING DISPERSAL ROUTES - PHYLOGEOGRAPHY OF THE ARCTIC ANTARCTIC DISJUNCT SEAWEED ACROSIPHONIA-ARCTA (CHLOROPHYTA)

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    VANOPPEN, MJH; DIEKMANN, OE; WIENCKE, C; STAM, WT; OLSEN, JL

    Phylogenetic relationships in the Arctic-Antarctic disjunct seaweed species Acrosiphonia arcta (Dillwyn) J. G. Agardh (Acrosiphoniales, Chlorophyta) were examined using restriction fragment-length polymorphism analysis of the fast-evolving nuclear ribosomal intergenic spacer (IGS) region and random

  19. A survey of Polytomella (Chlorophyceae, Chlorophyta) strains in public culture collections.

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    MacDonald, Shelley M; Lee, Robert W

    2016-08-01

    Polytomella is a genus of colorless green algae in the Reinhardtinia clade of the Chlamydomonadales, which has proven useful for a broad range of studies particularly those exploring the evolutionary loss of photosynthesis and mitochondrial genomics/biochemistry. Although 13 Polytomella strain accessions are currently available from public culture collections, the taxonomic status and redundancy of many of these strains is not clear because of possible mix-ups, deficient historical records, and incomplete molecular data. This study therefore considers previously available and/or new cox1 and mitochondrial DNA telomere sequences from all 13 Polytomella strain accessions. Among four of these, namely P. parva SAG 63-3, P. piriformis SAG 63-10, P. capuana SAG 63-5, and P. magna SAG 63-9, cox1 and mitochondrial telomere regions are both highly divergent between strains. All of the remaining nine Polytomella strain accessions have cox1 sequences that are identical to that of P. parva SAG 63-3 and although five of these have a mitochondrial telomere haplotype that is identical to that of P. parva SAG 63-3, the remaining four have one of three different haplotypes. Among the 10 strains with identical cox1 sequences, we suggest that three of the telomere haplotypes are associated with distinct geographical isolates of Polytomella and the fourth evolved from one of these isolates during 50 years of active culture. © 2016 Phycological Society of America.

  20. A dichotomous species of Codium (Bryopsidales, Chlorophyta is colonizing northern Chile Una especie dicotómica de Codium (Bryopsidales, Chlorophyta está colonizando el norte de Chile

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    ALEJANDRA GONZÁLEZ

    2004-06-01

    Full Text Available In late 2001 and early 2002, a dichotomous species of Codium appeared colonizing the low intertidal and shallow subtidal bottoms of Caldera Bay, northern Chile (27° 03’ S, 70° 51’ W. Due to the ecological and economic impact the species is having in Caldera Bay and its potential spread along the Chilean coastline, we studied the taxonomic identity of the species and examined its relationships with other dichotomous species of Codium reported for temperate Pacific South America. Morphological analyses suggest that the seaweeds from Caldera Bay belong to Codium fragile (Suringar Hariot. Not only is there strong agreement in internal and external morphological characters, but among all the species reported for Peru and Chile, this is the only one exhibiting utricles with rounded, apiculate tip terminating in a mucron. This species has a broad geographic distribution in temperate waters. In Chile it was known only from the coasts of Valdivia to the Straits of Magellan (39° 48’ S, 73° 26’ W to 53° 10’ S, 73° 49’ W. This is the first record of C. fragile in northern Chile, and this study discusses several alternative hypotheses for the presence of the species into this area. The morphological characteristics of the material collected in Caldera partially agree with diagnostic characters known for C. fragile subspecies tasmanicum and C. fragile subspecies tomentosoides. However, the rapid population spread of the species in northern Chile, and recent molecular analysis support the identification of this form as the invasive C. fragile subspecies tomentosoidesA fines de 2001 y principio de 2002, apareció en el norte de Chile una especie del género Codium, de morfología dicotómica, colonizando los niveles intermareales y submareales de la Bahía de Caldera (27° 03’ S, 70° 51’ O. Debido al impacto ecológico y económico que ha provocado esta especie en la Bahía de Caldera y a su dispersión potencial a lo largo de la costa de

  1. Evaluating the Species Boundaries of Green Microalgae (Coccomyxa, Trebouxiophyceae, Chlorophyta Using Integrative Taxonomy and DNA Barcoding with Further Implications for the Species Identification in Environmental Samples.

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    Tatyana Darienko

    Full Text Available Integrative taxonomy is an approach for defining species and genera by taking phylogenetic, morphological, physiological, and ecological data into account. This approach is appropriate for microalgae, where morphological convergence and high levels of morphological plasticity complicate the application of the traditional classification. Although DNA barcode markers are well-established for animals, fungi, and higher plants, there is an ongoing discussion about suitable markers for microalgae and protists because these organisms are genetically more diverse compared to the former groups. To solve these problems, we assess the usage of a polyphasic approach combining phenotypic and genetic parameters for species and generic characterization. The application of barcode markers for database queries further allows conclusions about the 'coverage' of culture-based approaches in biodiversity studies and integrates additional aspects into modern taxonomic concepts. Although the culture-dependent approach revealed three new lineages, which are described as new species in this paper, the culture-independent analyses discovered additional putative new species. We evaluated three barcode markers (V4, V9 and ITS-2 regions, nuclear ribosomal operon and studied the morphological and physiological plasticity of Coccomyxa, which became a model organism because its whole genome sequence has been published. In addition, several biotechnological patents have been registered for Coccomyxa. Coccomyxa representatives are distributed worldwide, are free-living or in symbioses, and colonize terrestrial and aquatic habitats. We investigated more than 40 strains and reviewed the biodiversity and biogeographical distribution of Coccomyxa species using DNA barcoding. The genus Coccomyxa formed a monophyletic group within the Trebouxiophyceae separated into seven independent phylogenetic lineages representing species. Summarizing, the combination of different characteristics

  2. DNA-Based Taxonomy in Ecologically Versatile Microalgae: A Re-Evaluation of the Species Concept within the Coccoid Green Algal Genus Coccomyxa (Trebouxiophyceae, Chlorophyta.

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    Veronica Malavasi

    Full Text Available Coccomyxa is a genus of unicellular green algae of the class Trebouxiophyceae, well known for its cosmopolitan distribution and great ecological amplitude. The taxonomy of this genus has long been problematic, due to reliance on badly-defined and environmentally variable morphological characters. In this study, based on the discovery of a new species from an extreme habitat, we reassess species circumscription in Coccomyxa, a unicellular genus of the class Trebouxiophyceae, using a combination of ecological and DNA sequence data (analyzed with three different methods of algorithmic species delineation. Our results are compared with those of a recent integrative study of Darienko and colleagues that reassessed the taxonomy of Coccomyxa, recognizing 7 species in the genus. Expanding the dataset from 43 to 61 sequences (SSU + ITS rDNA resulted in a different delimitation, supporting the recognition of a higher number of species (24 to 27 depending on the analysis used, with the 27-species scenario receiving the strongest support. Among these, C. melkonianii sp. nov. is described from material isolated from a river highly polluted by heavy metals (Rio Irvi, Sardinia, Italy. Analyses performed on ecological characters detected a significant phylogenetic signal in six different characters. We conclude that the 27-species scenario is presently the most realistic for Coccomyxa and we suggest that well-supported lineages distinguishable by ecological preferences should be recognized as different species in this genus. We also recommend that for microbial lineages in which the overall diversity is unknown and taxon sampling is sparse, as is often the case for green microalgae, the results of analyses for algorithmic DNA-based species delimitation should be interpreted with extreme caution.

  3. Combining and Comparing Coalescent, Distance and Character-Based Approaches for Barcoding Microalgaes: A Test with Chlorella-Like Species (Chlorophyta.

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    Shanmei Zou

    Full Text Available Several different barcoding methods of distinguishing species have been advanced, but which method is the best is still controversial. Chlorella is becoming particularly promising in the development of second-generation biofuels. However, the taxonomy of Chlorella-like organisms is easily confused. Here we report a comprehensive barcoding analysis of Chlorella-like species from Chlorella, Chloroidium, Dictyosphaerium and Actinastrum based on rbcL, ITS, tufA and 16S sequences to test the efficiency of traditional barcoding, GMYC, ABGD, PTP, P ID and character-based barcoding methods. First of all, the barcoding results gave new insights into the taxonomic assessment of Chlorella-like organisms studied, including the clear species discrimination and resolution of potentially cryptic species complexes in C. sorokiniana, D. ehrenbergianum and C. Vulgaris. The tufA proved to be the most efficient barcoding locus, which thus could be as potential "specific barcode" for Chlorella-like species. The 16S failed in discriminating most closely related species. The resolution of GMYC, PTP, P ID, ABGD and character-based barcoding methods were variable among rbcL, ITS and tufA genes. The best resolution for species differentiation appeared in tufA analysis where GMYC, PTP, ABGD and character-based approaches produced consistent groups while the PTP method over-split the taxa. The character analysis of rbcL, ITS and tufA sequences could clearly distinguish all taxonomic groups respectively, including the potentially cryptic lineages, with many character attributes. Thus, the character-based barcoding provides an attractive complement to coalescent and distance-based barcoding. Our study represents the test that proves the efficiency of multiple DNA barcoding in species discrimination of microalgaes.

  4. Combining and Comparing Coalescent, Distance and Character-Based Approaches for Barcoding Microalgaes: A Test with Chlorella-Like Species (Chlorophyta).

    Science.gov (United States)

    Zou, Shanmei; Fei, Cong; Song, Jiameng; Bao, Yachao; He, Meilin; Wang, Changhai

    2016-01-01

    Several different barcoding methods of distinguishing species have been advanced, but which method is the best is still controversial. Chlorella is becoming particularly promising in the development of second-generation biofuels. However, the taxonomy of Chlorella-like organisms is easily confused. Here we report a comprehensive barcoding analysis of Chlorella-like species from Chlorella, Chloroidium, Dictyosphaerium and Actinastrum based on rbcL, ITS, tufA and 16S sequences to test the efficiency of traditional barcoding, GMYC, ABGD, PTP, P ID and character-based barcoding methods. First of all, the barcoding results gave new insights into the taxonomic assessment of Chlorella-like organisms studied, including the clear species discrimination and resolution of potentially cryptic species complexes in C. sorokiniana, D. ehrenbergianum and C. Vulgaris. The tufA proved to be the most efficient barcoding locus, which thus could be as potential "specific barcode" for Chlorella-like species. The 16S failed in discriminating most closely related species. The resolution of GMYC, PTP, P ID, ABGD and character-based barcoding methods were variable among rbcL, ITS and tufA genes. The best resolution for species differentiation appeared in tufA analysis where GMYC, PTP, ABGD and character-based approaches produced consistent groups while the PTP method over-split the taxa. The character analysis of rbcL, ITS and tufA sequences could clearly distinguish all taxonomic groups respectively, including the potentially cryptic lineages, with many character attributes. Thus, the character-based barcoding provides an attractive complement to coalescent and distance-based barcoding. Our study represents the test that proves the efficiency of multiple DNA barcoding in species discrimination of microalgaes.

  5. Classification of planctonema-like algae, including a new genus Planctonemopsis gen. nov., a new species Planctonema gelatinosum sp. nov. and a reinstated genus Psephonema (Trebouxiophyceae, Chlorophyta).

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    Liu, Xudong; Zhu, Huan; Liu, Benwen; Liu, Guoxiang; Hu, Zhengyu

    2017-08-01

    Planctonema-like species consist of planktonic green algae and are found throughout the world. Their characteristic morphology, which includes short and slender filaments consisting of side-by-side or distant cylindrical cells enclosed in a fine and hyaline sheath, makes them easily distinguishable. To date, Planctonema lauterbornii was the only taxon accepted for this group. However, descriptions from different materials have revealed notable morphological differences, including the presence/absence of a pyrenoid, a mucilage sheath and an apical thickening of the cell wall. In this study, six strains of Planctonema-like species were identified and successfully cultured in the laboratory. We used a molecular approach to determine their taxonomic relationships and phylogenetic positions. The molecular analysis resolved them to at least three genera. The genus Planctonema was positioned in Trebouxiophyceae as an incertae sedis taxon that is closely related to Oocystaceae and was divided into two species. Planctonema gelatinosum was determined to be a new species with approximately twice the width and a thicker mucilage sheath, which differentiated it from the type species Planctonema lauterbornii. The genus Psephonema was reinstated based on 1.5-2 times length-width ratio than Planctonema and the big difference on the rbcL cpDNA gene marker and an intron insertion in the 18S rDNA. A new genus, Planctonemopsis, which represents the pyrenoid-present strains among the Planctonema-like species, was established. Planctonemopsis was positioned within Oocystaceae as a new clade and is distantly related to the other two genera. Taxonomic diversity was proven by distinctive morphological differences and phylogenetic divergence in the Planctonema-like group identified herein. © 2017 Phycological Society of America.

  6. Silica gel matrix immobilized Chlorophyta hydrodictyon africanum ...

    African Journals Online (AJOL)

    Chlorophyta hydrodictyon africanum was immobilized on a silica gel matrix to improve its mechanical properties. The algae-silica gel adsorbent was used for batch sorption studies of a cationic dye, methylene blue (MB). Optimum adsorption was obtained with a dosage of 0.8 g bio sorbent. Results from sorption studies ...

  7. Proliferation of group II introns in the chloroplast genome of the green alga Oedocladium carolinianum (Chlorophyceae

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    Jean-Simon Brouard

    2016-10-01

    Full Text Available Background The chloroplast genome sustained extensive changes in architecture during the evolution of the Chlorophyceae, a morphologically and ecologically diverse class of green algae belonging to the Chlorophyta; however, the forces driving these changes are poorly understood. The five orders recognized in the Chlorophyceae form two major clades: the CS clade consisting of the Chlamydomonadales and Sphaeropleales, and the OCC clade consisting of the Oedogoniales, Chaetophorales, and Chaetopeltidales. In the OCC clade, considerable variations in chloroplast DNA (cpDNA structure, size, gene order, and intron content have been observed. The large inverted repeat (IR, an ancestral feature characteristic of most green plants, is present in Oedogonium cardiacum (Oedogoniales but is lacking in the examined members of the Chaetophorales and Chaetopeltidales. Remarkably, the Oedogonium 35.5-kb IR houses genes that were putatively acquired through horizontal DNA transfer. To better understand the dynamics of chloroplast genome evolution in the Oedogoniales, we analyzed the cpDNA of a second representative of this order, Oedocladium carolinianum. Methods The Oedocladium cpDNA was sequenced and annotated. The evolutionary distances separating Oedocladium and Oedogonium cpDNAs and two other pairs of chlorophycean cpDNAs were estimated using a 61-gene data set. Phylogenetic analysis of an alignment of group IIA introns from members of the OCC clade was performed. Secondary structures and insertion sites of oedogonialean group IIA introns were analyzed. Results The 204,438-bp Oedocladium genome is 7.9 kb larger than the Oedogonium genome, but its repertoire of conserved genes is remarkably similar and gene order differs by only one reversal. Although the 23.7-kb IR is missing the putative foreign genes found in Oedogonium, it contains sequences coding for a putative phage or bacterial DNA primase and a hypothetical protein. Intergenic sequences are 1.5-fold

  8. Production of terpenes in the culture of Chlorophyceae and Rhodophyta

    Science.gov (United States)

    Abe, M.; Hashimoto, S.

    2014-12-01

    Terpenes show high reactivity in the troposphere, contributing to organic aerosol reactions with OH radicals. One of the main sources of terpenes in the atmosphere is terrestrial plants. It has been recently reported that marine phytoplankton also produce monoterpenes (Yassaa et al: 2008). Because aerosol production of natural origin affects the cloud cover over the open ocean, it is important to investigate the origin of aerosol generation in the open ocean. In this study, we investigated the production of terpenes and isoprene with a focus on Chlamydomonas (Chlorophyceae) and Rhodella maculata (Rhodophyta). Concentrations of terpenes and isoprene were measured using a dynamic headspace (GERSTEL DHS)—gas chromatograph (Agilent 6890N)—mass spectrometer (Agilent 5975C). In addition, chlorophyll a was measured using a fluorometer (Turner TD-700). The results showed that isoprene, α-pinene, and β-pinene were produced by Chlamydomonas sp. and that isoprene, limonene, and camphene were produced by Rhodella maculata. Chlamydomonas sp. produced α-pinene and β-pinene, similar to land plants. The ratio of the pinene/isoprene concentrations in the atmosphere over seawater where phytoplankton are blooming has been reported as approximately 0.7 (Yassaa et al: 2008). In this experiment, the pinene/isoprene concentration ratios in the cultures were approximately 0.1. This result indicates that marine phytoplankton may not be ignored in the marine atmosphere chemistry of terpenes.

  9. Chlorophyta filamentosas do município de Cáceres e arredores, Mato Grosso, Brasil: uma contribuição ao seu conhecimento Filamentous Chlorophyta from the Cáceres region, Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Izabel Cristina Alves Dias

    1989-12-01

    Full Text Available São descritas, comentadas e ilustradas 12 espécies de Chlorophyta filamentosas coletadas durante a II Expedição do Programa Polonoroeste/Conselho Nacional de Desenvolvimento Científico e Tecnológico/Museu Nacional da Universidade Federal do Rio de Janeiro à região de Cáceres e arredores, Mato Grosso, Brasil. Do total de espécies apresentadas neste trabalho nove constituem primeiras citações de ocorrência no Estado de Mato Grosso e seis no Brasil.Twelve species of filamentous Chlorophyta from the municipality of Cáceres and surroundings, state of Mato Grosso, Brazil, are described, illustrated, and discussed. Nine species were documented for the first time for Mato Grosso, and six for the Brazilian territory.

  10. ARCTIC-ANTARCTIC DISJUNCTIONS IN THE BENTHIC SEAWEEDS ACROSIPHONIA-ARCTA (CHLOROPHYTA) AND DESMARESTIA-VIRIDIS-WILLII (PHAEOPHYTA) ARE OF RECENT ORIGIN

    NARCIS (Netherlands)

    VANOPPEN, MJH; OLSEN, JL; STAM, WT; VANDENHOEK, C; WIENCKE, C

    Two examples of the most extreme biogeographic disjunctions in benthic marine algae are found in Acrosiphonia arcta (Chlorophyta) and Desmarestia viridis/willii (Phaeophyta). Both species are members of the Arctic and Antarctic boreal and subboreal marine floras. Although both genera have temperate

  11. Endogenous cytokinins in three genera of microalgae from the chlorophyta

    Czech Academy of Sciences Publication Activity Database

    Ördög, V.; Stirk, W. A.; van Staden, J.; Novák, Ondřej; Strnad, Miroslav

    2004-01-01

    Roč. 40, č. 1 (2004), s. 88-95 ISSN 0022-3646 R&D Projects: GA ČR GA522/03/0323; GA AV ČR IBS5038351 Institutional research plan: CEZ:AV0Z5038910 Keywords : aromatic cytokinins * Chlorophyta * endogenous cytokinin content Subject RIV: EC - Immunology Impact factor: 2.490, year: 2004

  12. Screening and Evaluation of Some Green Algal Strains (Chlorophyceae Isolated from Freshwater and Soda Lakes for Biofuel Production

    Directory of Open Access Journals (Sweden)

    Ramganesh Selvarajan

    2015-07-01

    Full Text Available Microalgae are photosynthetic microorganisms that can produce lipids, proteins and carbohydrates in large amounts and within short periods of time and these can be processed into both biofuels and other useful commercial products. Due to this reason microalgae are considered as a potential source of renewable energy; and one of the most important decisions in obtaining oil from microalgae is the choice of species. In this study, the potential of Chlorophyceae species isolated from freshwater and soda lakes in Hungary and Romania (Central Europe were characterized and evaluated by determining their biomass accumulation, lipid productivity, fatty acid profiles, and biodiesel properties besides protein and carbohydrate productivity. Out of nine strains tested, three accumulated more than 40% dry weight of protein, four accumulated more than 30% dry weight of carbohydrate and the strain Chlorella vulgaris LC8 accumulated high lipid content (42.1% ± 2.6% with a favorable C16-C18 fatty acid profile (77.4% as well as suitable biodiesel properties of high cetane number (57.3, low viscosity (4.7 mm2/s, lower iodine number (75.18 g I2/100 g, relative cloud point (8.8 °C and negative cold filter plugging point (−6.5 °C. Hence the new strain, Chlorella vulgaris LC8 has potential as a feedstock for the production of excellent quality biodiesel.

  13. Diversity and Abundance of Chlorophyta in Krakal Beach, Gunung Kidul, Yogyakarta

    Science.gov (United States)

    Putri, A. C.; Nugroho, I. C.; Firdaus, N. U. N.; Puspita, N. O. J.; Fajrin, S. A. R.; Hamzah, S. D. A.

    2017-10-01

    Chlorophyta plays an important role in energy flow as the main producer in marine food chain, material circulation, bioaccumulation, and bio-indicator in the intertidal zone. Several genera of Chlorophyta have been used by local society around coastal area of Gunung Kidul, Yogyakarta as local product, but the research about diversity and abundance information of Chlorophyta in Krakal beach was not yet understood. The aim of this study is to gain the information about diversity and abundancy of Chlorophyta in Krakal Beach, Gunung Kidul,Yogyakarta. This research was conducted in March 11th 2017. This research utilizes Line Transect and Stratified Random Sampling method which is used 1x1 m plot. There are six genera of Chlorophyta have been identified in this research, such as Chaetomorpha sp.; Boergesenia sp; Ulva sp.; Cladophora sp.; Enteromorpha sp.; and Halicystis sp. From 6 genera of Chlorophyta, the highest genera coverage is Enteromorpha sp. (9.88%). This research is expected to record data of macroalgae abundance especially Chlorophyta, in Krakal Beach. By this research, monitoring of macroalgae could be done and supported by government and local people to maintain the sustainability of Chlorophyta.

  14. Plastomes of the green algae Hydrodictyon reticulatum and Pediastrum duplex (Sphaeropleales, Chlorophyceae

    Directory of Open Access Journals (Sweden)

    Hilary A. McManus

    2017-05-01

    Full Text Available Background Comparative studies of chloroplast genomes (plastomes across the Chlorophyceae are revealing dynamic patterns of size variation, gene content, and genome rearrangements. Phylogenomic analyses are improving resolution of relationships, and uncovering novel lineages as new plastomes continue to be characterized. To gain further insight into the evolution of the chlorophyte plastome and increase the number of representative plastomes for the Sphaeropleales, this study presents two fully sequenced plastomes from the green algal family Hydrodictyaceae (Sphaeropleales, Chlorophyceae, one from Hydrodictyon reticulatum and the other from Pediastrum duplex. Methods Genomic DNA from Hydrodictyon reticulatum and Pediastrum duplex was subjected to Illumina paired-end sequencing and the complete plastomes were assembled for each. Plastome size and gene content were characterized and compared with other plastomes from the Sphaeropleales. Homology searches using BLASTX were used to characterize introns and open reading frames (orfs ≥ 300 bp. A phylogenetic analysis of gene order across the Sphaeropleales was performed. Results The plastome of Hydrodictyon reticulatum is 225,641 bp and Pediastrum duplex is 232,554 bp. The plastome structure and gene order of H. reticulatum and P. duplex are more similar to each other than to other members of the Sphaeropleales. Numerous unique open reading frames are found in both plastomes and the plastome of P. duplex contains putative viral protein genes, not found in other Sphaeropleales plastomes. Gene order analyses support the monophyly of the Hydrodictyaceae and their sister relationship to the Neochloridaceae. Discussion The complete plastomes of Hydrodictyon reticulatum and Pediastrum duplex, representing the largest of the Sphaeropleales sequenced thus far, once again highlight the variability in size, architecture, gene order and content across the Chlorophyceae. Novel intron insertion sites and unique

  15. Chlorococcales nuevas para el embalse Paso de las Piedras (Buenos Aires, Argentina New Chlorococcales for Paso de las Piedras Reservoir (Buenos Aires, Argentine

    Directory of Open Access Journals (Sweden)

    Carolina Fernández

    2005-12-01

    Full Text Available En el presente trabajo se citan e ilustran 22 especies pertenecientes al orden Chlorococcales (Chlorophyceae, Chlorophyta halladas en el embalse Paso de las Piedras que representan nuevas citas para este ambiente. Pseudokirchneriella subcapitata, Tetraedron hemisphaericum y Scenedesmus semipulcher constituyen nuevas citas para la República Argentina.In this paper, we record and illustrate 22 species of Chlorococcales (Chlorophyceae, Chlorophyta found in Paso de las Piedras Reservoir, which are new records for this area. Pseudokirchneriella subcapitata, Tetraedron hemisphaericum and Scenedesmus semipulcher are new for Argentina.

  16. Life history and culture studies of Monostroma oxyspermum (Kutz.) Doty (Monostromataceae, Chlorophyceae) growing in estuarine conditions along the central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Deshmukhe, G.V.; Dhargalkar, V.K.; Untawale, A.G.

    The specimen of Monostroma oxyspermum (Chlorophyceae) were collected in Indian waters from mangrove ecosystem of Shirgao Creek, Ratnagiri, Maharashtra; Terekhol Creek, Goa; and Kali Estuary, Karwar Karnataka. The life history of these were studied...

  17. Biochemical activity of di- and polyamines in the green alga Chlorella vulgaris Beijerinck (Chlorophyceae

    Directory of Open Access Journals (Sweden)

    Romuald Czerpak

    2011-01-01

    Full Text Available This study concerns on the influence of diamines (agmatine, putrescine and polyamines (spermine, spermidine upon the growth and the content of chlorophyll a and b, monosaccharides and proteins in the cells of alga Chlorella vulgaris Beijerinck (Chlorophyceae. In the experiments agmatine, putrescine, spermine and spermidine in the range of concentrations 10-6-10-3 M were used. At the concentration 10-3 M and the 1st day of cultivation, they have a toxic effect on growth of the algae. It was found that di- and polyamines used within the range of concentration 10-6-10-4 M stimulate the growth and the contents of analysed biochemical parameters in the cells of C. vulgaris. The most stimulating influence on metabolism of the alga was demonstrated by spermidine and putrescine at concentration of 10-4 M. Agmatine and spermine were characterised by a lower biological activity than spermidine and putrescine demonstrated the most stimulating influence.

  18. Effect of isomers of hydroxybenzoic acid on the growth and metabolism of Chlorella vulgaris Beijerinck (Chlorophyceae

    Directory of Open Access Journals (Sweden)

    Andrzej Bajguz

    2014-01-01

    Full Text Available The isomers o-, m-, and p- of hydroxybenzoic acid (HBA in the concentration range 10-1-10-4 M in the unicellular green alga Chlorella vulgaris (Chlorophyceae display marked biological activity. The o-HBA isomer, commonly known as salicylic acid, in a concentration of 10-4 M exerted the most stimulating effect on the parameters analysed (the number of cells, dry mass, the content of chlorophylls a and h, carotenoids, soluble proteins and their secretion, monosaccharides, DNA and RNA whereas p-HBA had weak stimulating properties. On the other hand, m-HBA had a weak inhibitory effect on the growth of C. vulgaris and all the biochemical parameters analysed in comparison with the control culture of algae devoid of HBA isomers.

  19. Meiotic genes and sexual reproduction in the green algal class Trebouxiophyceae (Chlorophyta)

    KAUST Repository

    Fučíková, Karolina

    2015-04-06

    © 2015 Phycological Society of America. Sexual reproduction is widespread in eukaryotes and is well documented in chlorophytan green algae. In this lineage, however, the Trebouxiophyceae represent a striking exception: in contrast to its relatives Chlorophyceae and Ulvophyceae this group appears to be mostly asexual, as fertilization has been rarely observed. Assessments of sexual reproduction in the Trebouxiophyceae have been based on microscopic observation of gametes fusing. New genomic data offer now the opportunity to check for the presence of meiotic genes, which represent an indirect evidence of a sexual life cycle. Using genomic and transcriptomic data for 12 taxa spanning the phylogenetic breadth of the class, we tried to clarify whether genuine asexuality or cryptic sexuality is the most likely case for the numerous putatively asexual trebouxiophytes. On the basis of these data and a bibliographic review, we conclude that the view of trebouxiophytes as primarily asexual is incorrect. In contrast to the limited number of reports of fertilization, meiotic genes were found in all genomes and transcriptomes examined, even in species presumed asexual. In the taxa examined the totality or majority of the genes were present, Helicosporidium and Auxenochlorella being the only partial exceptions (only four genes present). The evidence of sex provided by the meiotic genes is phylogenetically widespread in the class and indicates that sexual reproduction is not associated with any particular morphological or ecological trait. On the basis of the results, we expect that the existence of the meiotic genes will be documented in all trebouxiophycean genomes that will become available in the future.

  20. Clorofíceas marinhas bentônicas da Praia de Serrambi, Pernambuco, Brasil Benthic marine Chlorophyceae from Serrambi Beach, Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    Sônia Maria Barreto Pereira

    1998-04-01

    Full Text Available É apresentado o levantamento florístico sobre as clorofíceas marinhas bentônicas encontradas na Praia de Serrambi, litoral Sul do Estado de Pernambuco. O material estudado foi coletado em três estações, as quais foram visitadas mensalmente durante o período de abril de 1986 a setembro de 1987. As clorofíceas foram representadas na flora local por 39 espécies, três variedades e uma forma, pertencentes às ordens Ulotrichales, Ulvales, Siphonocladales, Cladophorales, Caulerpales e Dasycladales. Acetabularia calyculus Quoy & Gaimard. In Freycinet, Bryopsis pennata Lamouroux, Bryopsis plumosa (Hudson C. Agardh, Caulerpa ambigua Okamura, Caulerpa serrulata (Forsskål J. Agardh emend Børgesen, Chaetomorpha brachygona Harvey, Cladophora coelothrix Kützing, Cladophoropsis membranacea (C. Agardh Børgesen, Codium intertextum Collins & Hervey, Ernodesmis verticillata (Kützing Børgesen são novas referências para a flora do litoral de Pernambuco. Pringsheimiella scutata (Reinke von Höhnel ex Marchewianka o é também para o litoral continental do Brasil. Halimeda opuntia (L. Lamouroux foi hospedeira de maior número de epífitas, enquanto Bryopsis plumosa, quando epífita, foi a que cresceu sobre maior número de hospedeiros.This survey presents studies about benthics marine chlorophyceae found in the Serrambi Beach, South coast of Pernambuco. The material studied was collected in three stations, which were visited monthly during the period from April, 1986 to September, 1987. The chlorophyceae were represented in this flora by 39 species, three varieties and one form, from orders Ulotrichales, Ulvales, Siphonocladales, Cladophorales, Caulerpales and Dasycladales. Acetabularia calyculus Quoy & Gaimard. In Freycinet, Bryopsis pennata Lamouroux, Bryopsis plumosa (Hudson C. Agardh, Caulerpa ambigua Okamura, Caulerpa serrulata (Forsskål J. Agardh emend Børgesen, Chaetomorpha brachygona Harvey, Cladophora coelothrix Kützing, Cladophoropsis

  1. Inclusion of chloroplast genes that have undergone expansion misleads phylogenetic reconstruction in the Chlorophyta.

    Science.gov (United States)

    Novis, Phil M; Smissen, Rob; Buckley, Thomas R; Gopalakrishnan, Kishore; Visnovsky, Gabriel

    2013-11-01

    Chlorophytes comprise a substantial proportion of green plant diversity. However, sister-group relationships and circumscription of the classes Chlorophyceae, Trebouxiophyceae, and Ulvophyceae have been problematic to resolve. Some analyses support a sister relationship between the trebouxiophycean Leptosira and chlorophyceans, potentially altering the circumscription of two classes, also supported by a shared fragmentation in the chloroplast gene rpoB. We sought to determine whether the latter is a synapomorphy or whether the supporting analyses are vulnerable to systematic bias. We sequenced a portion of rpoB spanning the fragmented region in strains for which it had not previously been sampled: four Chlorophyceae, six counterclockwise (CCW) group (ulvophyceans and trebouxiophyceans) and one streptophyte. We then explored the effect of subsampling proteins and taxa on phylogenetic reconstruction from a data set of 41 chloroplast proteins. None of the CCW or streptophyte strains possessed the split in rpoB, including inferred near relatives of Leptosira, but it was found in all chlorophycean strains. We reconstructed alternative phylogenies (Leptosira + Chlorophyceae and Leptosira + Chlorellales) using two different protein groups (Rpo and Rps), both subject to coding-region expansion. A conserved region of RpoB remained suitable for analysis of more recent divergences. The Rps sequences can explain earlier findings linking Leptosira with the Chlorophyceae and should be excluded from phylogenetic analyses attempting to resolve deep nodes because their expansion violates the assumptions of substitution models. We reaffirm that Leptosira is a trebouxiophycean and that fragmentation of rpoB has occurred at least twice in chlorophyte evolution.

  2. Seasonal variation in biomass and species composition of ...

    Indian Academy of Sciences (India)

    in April. The stranded weeds constituted a total of 62 species during the entire study period. Of this, Rhodophyta ranked high with 26 species followed by Chlorophyta with 22 species and Phaeophyta with 14 species. The stranded seaweeds that were washed ashore provide valuable floristic information about the intertidal ...

  3. Seasonal variation in biomass and species composition of ...

    Indian Academy of Sciences (India)

    The stranded weeds constituted a total of 62 species during the entire study period.Of this,Rhodophyta ranked high with 26 species followed by Chlorophyta with 22 species and Phaeophyta with 14 species.The stranded seaweeds that were washed ashore provide valuable floristic information about the intertidal and near ...

  4. Meiotic genes and sexual reproduction in the green algal class Trebouxiophyceae (Chlorophyta)

    Czech Academy of Sciences Publication Activity Database

    Fučíková, K.; Pažoutová, Marie; Rindi, F.

    2015-01-01

    Roč. 51, č. 3 (2015), s. 419-430 ISSN 0022-3646 Institutional support: RVO:60077344 Keywords : algal genomes * Chlorophyta * green algae * meiotic genes * sexual reproduction * Trebouxiophyceae Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.536, year: 2015

  5. Lead (Pb heavy metal impacts in the green Ulva lactuca (Chlorophyceae marine algae

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    B. Saleh

    2016-05-01

    Full Text Available Toxicity of different lead (Pb (0, 2, 4 and 8 mg/L concentrations in the green Ulva lactuca (Chlorophyta marine algae at physiological level has been investigated 48 h after Pb treatment under laboratory conditions. Thalus algae damages followed Pb treatment as revealed by microscopy test showed that the 4 and 8 mg/L Pb caused morphological changes in cells viability; whereas, no effect observed at the lowest Pb applied concentration (2 mg/L. Data revealed that Pb stress caused reduction in most investigated physiological parameters i.e. Pigments content, osmotic potential and membrane stability index values. This decline in osmotic potential was significantly (p ≤ 0.001 different. Whereas, estimated electric conductivity (EC values increased significantly (p ≤ 0.001 as applied Pb concentration increased. The current study allowed somewhat to highlight and better understanding Pb impacts in U. lactuca algae. Thereby, the studied algae could be used as a useful bioindicator in Pb polluted ecosystems.

  6. First record of Caulerpa cylindracea (Caulerpaceae, Chlorophyta in Andalusia (Southern Spain

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    Altamirano, María

    2014-12-01

    Full Text Available Three different species of Caulerpa (Caulerpaceae, Chlorophyta co-occur in the Mediterranean Sea: two of them are found at the central-eastern basin and are typically considered non aggressive components of the Lessepsian flora [(C. chemnitzia(Esper J.V. Lamouroux and C. racemosa var. lamourouxii (Turner Weber-van Bosse f. requienii(Montagne Weber van Bosse]; a third taxon, C. cylindracea Sonder has aggressively expanded its range since its first observation in 1990, and it is nowadays reported from nearly all the Mediterranean countries. We report a population of C. cylindracea from Almería (Andalusia, Southern Iberian Peninsula at −30 m depth as to be the westernmost record of the invasive variety on the Mediterranean European coast. Therefore, we made use of morphological description and molecular phylogenetics to provide a complete identification of this invasive seaweed in Southern Spain. Our findings are discussed in light of the composition of the receptor communities, such as maërl bed, edges of Posidonia oceanica (Linnaeus Delile, and their ecology. Our results confirmed the suggested directionality of the invasive pathway to be westward to the Strait of Gibraltar, mainly supported by sea currents and vectors of anthropogenic origin.En el Mar Mediterráneo se encuentran tres especies diferentes de Caulerpa (Caulerpaceae, Chlorophyta: dos de ellas se localizan en la cuenca centro oriental y se consideran componentes no agresivos de la flora Lessepsiana (C. chemnitzia(Esper J.V. Lamouroux and C. racemosa var. lamourouxii (Turner Weber-van Bosse f. requienii(Montagne Weber van Bosse; un tercer taxon, C. cylindracea Sonder ha expandido de manera agresiva su rango de distribución desde su primera observación en 1990, y actualmente se registra en casi todos los países de la cuenca mediterránea. En este trabajo se informa sobre una población de C. cylindracea en Almería (Andalucía, Sur de España, a −30 m de profundidad, que

  7. Atividade antioxidante in vitro de extratos de algumas algas verdes (Chlorophyta do litoral catarinense (Brasil Antioxidant in vitro activity of extracts of some green seaweed (Chlorophyta from southern Brazilian coast

    Directory of Open Access Journals (Sweden)

    Melissa dos Santos Raymundo

    2004-12-01

    Full Text Available O efeito antioxidante de quatro espécies de algas marinhas do filo Chlorophyta (Codium decorticatum, Enteromorpha intestinalis, Ulva fasciata e Chaetomorpha anteninna foi avaliado através da inibição da peroxidação do ácido linoléico em emulsão. Os extratos etéreos e metanólicos, na concentração de 0,01%, foram obtidos por extração seqüencial das biomassas secas. As espécies mais efetivas sobre a peroxidação lipídica foram Enteromorpha intestinalis e Chaetomorpha anteninna, com porcentagens de inibição acima de 70%. A habilidade dos extratos metanólicos para seqüestrar o peróxido de hidrogênio foi avaliada, obtendo-se valores médios para porcentagens de captura entre 1,26% e 20,01%. Além disto, quantificaram-se os teores de clorofila a, carotenóides totais e compostos fenólicos totais nas biomassas algais. Os resultados indicam que as algas verdes estudadas são uma fonte promissora de compostos biologicamente ativos com propriedades antioxidantes.The antioxidant activity of four species of green seaweeds of the phylo Chlorophyta (Codium decorticatum, Enteromorpha intestinalis, Ulva fasciata and Chaetomorpha anteninna collected at the seacoast of the State of Santa Catarina, Brazil, was evaluated by means of the inhibition of peroxidation of linoleic acid converted into emulsion. Both ethereal and methanolic extracts were obtained from dried biomasses by sequential extraction procedures in concentrations of 0.01%. The most efficient species towards lipid peroxidation were E. intestinalis and C. anteninna with inhibition yields above 70% .The capacity of methanolic extracts to quench hydrogen peroxide was also estimated. Mean values varied from 1.26 to 20.01%. Chlorophylls a, total carotenoids and phenolic compounds were also quantified in the biomasses. Results indicated that studied green seaweeds are a very promising source of biologically active compounds with antioxidant properties.

  8. Occurrence of arsenic in selected marine macroalgae from two coastal areas of South Australia. [Rhodophyceae; phaeophyceae; Chlorophyceae

    Energy Technology Data Exchange (ETDEWEB)

    Maher, W.A.; Clarke, S.M.

    1984-03-01

    Total arsenic concentrations have been measured in macroalgae specimens from two coastal areas of South Australia. Phaeophyta in both areas were found to contain elevated arsenic concentrations (42.2-179 ..mu..g g/sup -1/ and 26.3-65.3 ..mu..g g/sup -1/) relative to Rhodophyta (17.6-31.3 ..mu..g g/sup -1/ and 12.5-16.2 ..mu..g g/sup -1/) and Chlorophyta (6.3-16.3 ..mu..g g/sup -1/ and 9.9-10.8 ..mu..g g/sup -1/). 13 references, 3 tables.

  9. Screening of Endophytic Fungi from Chlorophyta and Phaeophyta for Antibacterial Activity

    Science.gov (United States)

    Rahaweman, A. C.; Pamungkas, J.; Madduppa, H.; Thoms, C.; Tarman, K.

    2016-01-01

    Chlorophyta and Phaeophyta macroalgae are important sources of secondary metabolites with pharmaceutically relevant antibacterial, antifungal and antiviral bioactivities. Oftentimes, these algae-derived compounds are, in fact, produced by endophytic fungi living inside the macroalgal tissue. Numerous studies have shown that endophytic fungi can produce a broad range of active metabolites such as terpenes, alkaloids, and quinones. The aim of the present study was to screen fungal strains isolated from a variety of Caulerpa spp., Halimeda spp., and Sargassum spp. for antibacterial activity against Staphylococcus aureus and Escherichia coli. Thirteen morphologically different isolates were tested. Two of them showed pronounced activity against S. aureus in agar diffusion assays.

  10. Culturing Selenastrum capricornutum (Chlorophyta) in a synthetic algal nutrient medium with defined mineral particulates

    Science.gov (United States)

    Kuwabara, J.S.; Davis, J.A.; Chang, Cecily C.Y.

    1985-01-01

    Algal nutrient studies in chemically-defined media typically employ a synthetic chelator to prevent iron hydroxide precipitation. Micronutrient-particulate interactions may, however, significantly affect chemical speciation and hence biovailability of these nutrients in natural waters. A technique is described by which Selenastrum capricornutum Printz (Chlorophyta) may be cultured in a medium where trace metal speciation (except iron) is controlled, not by organic chelation, but by sorption onto titanium dioxide. Application of this culturing protocol in conjunction with results from sorption studies of nutrient ions on mineral particles provides a means of studying biological impacts of sorptive processes in aquatic environments. ?? 1985 Dr W. Junk Publishers.

  11. Karyotypic differences and evolutionary tendencies of some species ...

    Indian Academy of Sciences (India)

    Karyotypic differences and evolutionary tendencies of some species from the subgenus Obliquodesmus Mlad. of genus Scenedesmus Meyen. (Chlorophyta, Chlorococcales). BALIK DZHAMBAZOV1,3 ∗, RUMEN MLADENOV2, IVANKA TENEVA2 and DETELINA BELKINOVA2. 1Cell Biology Laboratory, Department of ...

  12. Seasonal variations in biomass and species composition of ...

    Indian Academy of Sciences (India)

    This study was carried out to evaluate the seasonal variations of seaweed biomass and species composition at six different sites along the coastal areas in Bushehr Province. Sampling depths varied among sites, from 0.3 to 2.0 m below mean sea level. A total of 37 (i.e., 10 Chlorophyta, 12 Phaeophyta and 15. Rhodophyta) ...

  13. Seasonal variations in biomass and species composition of ...

    Indian Academy of Sciences (India)

    This study was carried out to evaluate the seasonal variations of seaweed biomass and species composition at six different sites along the coastal areas in Bushehr Province. Sampling depths varied among sites, from 0.3 to 2.0 m below mean sea level. A total of 37 (i.e., 10 Chlorophyta, 12 Phaeophyta and 15 Rhodophyta) ...

  14. Karyotypic differences and evolutionary tendencies of some species ...

    Indian Academy of Sciences (India)

    Karyotypic differences and evolutionary tendencies of some species from the subgenus Obliquodesmus Mlad. of genus Scenedesmus Meyen (Chlorophyta, ... Department of Experimental Medical Science, BMC I 11, Lund University, 22184 Lund, Sweden; Department of Botany, University of Plovdiv, 24 Tsar Assen St., 4000 ...

  15. Lipidomic analysis of Botryococcus (Trebouxiophyceae, Chlorophyta) - Identification of lipid classes containing very long chain fatty acids by offline two-dimensional LC-tandem MS.

    Science.gov (United States)

    Řezanka, Tomáš; Lukavský, Jaromír; Vítová, Milada; Nedbalová, Linda; Sigler, Karel

    2018-04-01

    Very long chain fatty acids (VLCFAs) were identified in four strains of the green alga Botryococcus braunii (Trebouxiophyceae). The algae contained a series of monoenoic fatty acids up to triacontenoic acid and further VLCFAs in amounts around 1% of total fatty acids. The separation of lipid classes using hydrophilic interaction chromatography revealed that the most abundant VLCFAs (28:2, 28:1 and 28:0) were contained in neutral lipids (triacylglycerols and/or diacylglycerols) and in phospholipids (phosphatidic acid and/or phosphatidylcholine). Using non-aqueous reversed-phase liquid chromatography tandem mass spectrometry (NARP-LC/MS 2 ) of the appropriate collected fractions, molecular species of triacylglycerols containing one or two VLCFAs were described and phosphatidylcholines containing VLCFAs were separated for the first time. Because the presence of Botryosphaerella sudetica (Chlorophyceae) as contaminant of Botryococcus braunii strain Droop 1950/807-1 placed some doubts on the results of previous studies, a strain of this green alga of was also analyzed. In contrast to Botryococcus, C16, a substantially lower proportion of C18 polyunsaturated fatty acids and no VLCFAs were detected in Botryosphaerella. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Analysis of expressed sequence tags from the Ulva prolifera (Chlorophyta)

    Science.gov (United States)

    Niu, Jianfeng; Hu, Haiyan; Hu, Songnian; Wang, Guangce; Peng, Guang; Sun, Song

    2010-01-01

    In 2008, a green tide broke out before the sailing competition of the 29th Olympic Games in Qingdao. The causative species was determined to be Enteromorpha prolifera ( Ulva prolifera O. F. Müller), a familiar green macroalga along the coastline of China. Rapid accumulation of a large biomass of floating U. prolifera prompted research on different aspects of this species. In this study, we constructed a nonnormalized cDNA library from the thalli of U. prolifera and acquired 10 072 high-quality expressed sequence tags (ESTs). These ESTs were assembled into 3 519 nonredundant gene groups, including 1 446 clusters and 2 073 singletons. After annotation with the nr database, a large number of genes were found to be related with chloroplast and ribosomal protein, GO functional classification showed 1 418 ESTs participated in photosynthesis and 1 359 ESTs were responsible for the generation of precursor metabolites and energy. In addition, rather comprehensive carbon fixation pathways were found in U. prolifera using KEGG. Some stress-related and signal transduction-related genes were also found in this study. All the evidences displayed that U. prolifera had substance and energy foundation for the intense photosynthesis and the rapid proliferation. Phylogenetic analysis of cytochrome c oxidase subunit I revealed that this green-tide causative species is most closely affiliated to Pseudendoclonium akinetum (Ulvophyceae).

  17. Use of fatty acids in the chemotaxonomy of the family Selenastraceae (Sphaeropleales, Chlorophyceae).

    Science.gov (United States)

    Mori, Cilene Cristina; Bagatini, Inessa Lacativa; Garcia da Silva, Thais; Parrish, Christopher Charles; Henriques Vieira, Armando Augusto

    2018-04-06

    The family Selenastraceae includes many species of freshwater green microalgae with morphological characteristics that are so subtly different that it is difficult to discriminate species within it. Therefore, the use of the diacritical characteristics of traditional morphological taxonomy may be ineffective at differentiating among many species of the family. Chemotaxonomy based on fatty acid methyl ester (FAME) can help resolve uncertainties not completely addressed by other approaches, such as molecular studies of some species within the Selenastraceae. Here, we first tested three techniques for the analysis of microalgal FAME to choose the one that would provide the best profiles for chemotaxonomy: 1) direct transesterification (DT) of the biomass followed by gas chromatography coupled to mass spectrometry analysis (GC-MS); 2) extraction using chloroform and methanol, followed by transesterification (T) and then analysis by gas chromatography/flame ionization detector (GC-FID); and 3) extraction with chloroform and methanol and then separation into lipid classes using thin-layer chromatography (TLC) using the Iatroscan-Chromarod system. The tests were conducted on 12 strains (11 species) of Selenastraceae and one outgroup strain. The fatty acid profiles produced by the DT-GC-MS technique yielded the best results for the chemotaxonomy of the Selenastraceae species using 12 FAME. The proportion of the variance in the fatty acid profiles obtained with DT-GC-MS analysis explained by species was 85%, whereas the differences explained by strains was 92%. Therefore, DT-GC-MS was used to analyze other microalgae strains, totaling 15 species of 8 genera of green coccoid microalgae, including the recently described Curvastrum. The results with all strains showed that fatty acid profiles obtained by DT-GC-MS were significantly different (p < 0.001) among strains and among species. The variance in fatty acids profiles explained by separation into strains was 97

  18. Chlorophyta and Rhodophyta macroalgae: a source of health promoting phytochemicals.

    Science.gov (United States)

    Santos, Sonia A O; Vilela, Carla; Freire, Carmen S R; Abreu, Maria H; Rocha, Silvia M; Silvestre, Armando J D

    2015-09-15

    A detailed study of the lipophilic composition of Codium tomentosum, Ulva lactuca, Gracilaria vermiculophylla and Chondrus crispus macroalgae cultivated in the Portuguese coast was carried out by gas chromatography-mass spectrometry before and after alkaline hydrolysis. Their long-chain aliphatic alcohols and monoglycerides compositions are reported for the first time. Additionally, other new compounds were also identified: phytol and neophytadiene in C. tomentosum, U. lactuca and G. vermiculophylla and stigmasterol, α-tocopherol and 24-methylenecholesterol in C. tomentosum. The lipophilic fraction of the studied macroalgae are mainly constituted by fatty acids (110.1-1030.5mgkg(-1) of dry material) and sterols (14.8-1309.1mgkg(-1) of dry material). C. tomentosum showed to be a valuable source of stigmasterol (1229.0mgkg(-1) of dry material) and α-tocopherol (21.8mgkg(-1) of dry material). These results are a relevant contribution for the valorisation of these macroalgae species as sources of valuable phytochemicals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Carbon Partitioning in Green Algae (Chlorophyta and the Enolase Enzyme

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    Jürgen E. W. Polle

    2014-08-01

    Full Text Available The exact mechanisms underlying the distribution of fixed carbon within photoautotrophic cells, also referred to as carbon partitioning, and the subcellular localization of many enzymes involved in carbon metabolism are still unknown. In contrast to the majority of investigated green algae, higher plants have multiple isoforms of the glycolytic enolase enzyme, which are differentially regulated in higher plants. Here we report on the number of gene copies coding for the enolase in several genomes of species spanning the major classes of green algae. Our genomic analysis of several green algae revealed the presence of only one gene coding for a glycolytic enolase [EC 4.2.1.11]. Our predicted cytosolic localization would require export of organic carbon from the plastid to provide substrate for the enolase and subsequent re-import of organic carbon back into the plastids. Further, our comparative sequence study of the enolase and its 3D-structure prediction may suggest that the N-terminal extension found in green algal enolases could be involved in regulation of the enolase activity. In summary, we propose that the enolase represents one of the crucial regulatory bottlenecks in carbon partitioning in green algae.

  20. New Design Strategy for Development of Specific Primer Sets for PCR-Based Detection of Chlorophyceae and Bacillariophyceae in Environmental Samples▿ †

    Science.gov (United States)

    Valiente Moro, Claire; Crouzet, Olivier; Rasconi, Séréna; Thouvenot, Antoine; Coffe, Gérard; Batisson, Isabelle; Bohatier, Jacques

    2009-01-01

    Studying aquatic microalgae is essential for monitoring biodiversity and water quality. We designed new sets of 18S rRNA PCR primers for Chlorophyceae and Bacillariophyceae by using the ARB software and implementing a virtual PCR program. The results of specificity analysis showed that most of the targeted algal families were identified and nontargeted organisms, such as fungi or ciliates, were excluded. These newly developed PCR primer sets were also able to amplify microalgal rRNA genes from environmental samples with accurate specificity. These tools could be of great interest for studying freshwater microalgal ecology and for developing bioindicators of the health status of aquatic environments. PMID:19592531

  1. New design strategy for development of specific primer sets for PCR-based detection of Chlorophyceae and Bacillariophyceae in environmental samples.

    Science.gov (United States)

    Moro, Claire Valiente; Crouzet, Olivier; Rasconi, Séréna; Thouvenot, Antoine; Coffe, Gérard; Batisson, Isabelle; Bohatier, Jacques

    2009-09-01

    Studying aquatic microalgae is essential for monitoring biodiversity and water quality. We designed new sets of 18S rRNA PCR primers for Chlorophyceae and Bacillariophyceae by using the ARB software and implementing a virtual PCR program. The results of specificity analysis showed that most of the targeted algal families were identified and nontargeted organisms, such as fungi or ciliates, were excluded. These newly developed PCR primer sets were also able to amplify microalgal rRNA genes from environmental samples with accurate specificity. These tools could be of great interest for studying freshwater microalgal ecology and for developing bioindicators of the health status of aquatic environments.

  2. Tetraselmis indica (Chlorodendrophyceae, Chlorophyta), a new species isolated from salt pans in Goa, India

    Digital Repository Service at National Institute of Oceanography (India)

    Mani, A.; Anil, A.C.; Leliaert, F.; Delany, J.; Mesbahi, E.

    . The cells show marked phototaxis. Reproduction Vegetative reproduction is by transverse division of the protoplast into two (Figs 25, 26), three or four daughter cells within the parental theca. Cells sometimes divide asymmetrically. Nucleolar... and nuclear division are followed by cytoplasmic division. Daughter cells often develop flagella while still surrounded by the parental theca. The alga survives during unfavourable periods as cysts, which are capable of rejuvenation and normal development...

  3. A close-up view on ITS2 evolution and speciation - a case study in the Ulvophyceae (Chlorophyta, Viridiplantae

    Directory of Open Access Journals (Sweden)

    Caisová Lenka

    2011-09-01

    Full Text Available Abstract Background The second Internal Transcriber Spacer (ITS2 is a fast evolving part of the nuclear-encoded rRNA operon located between the 5.8S and 28S rRNA genes. Based on crossing experiments it has been proposed that even a single Compensatory Base Change (CBC in helices 2 and 3 of the ITS2 indicates sexual incompatibility and thus separates biological species. Taxa without any CBC in these ITS2 regions were designated as a 'CBC clade'. However, in depth comparative analyses of ITS2 secondary structures, ITS2 phylogeny, the origin of CBCs, and their relationship to biological species have rarely been performed. To gain 'close-up' insights into ITS2 evolution, (1 86 sequences of ITS2 including secondary structures have been investigated in the green algal order Ulvales (Chlorophyta, Viridiplantae, (2 after recording all existing substitutions, CBCs and hemi-CBCs (hCBCs were mapped upon the ITS2 phylogeny, rather than merely comparing ITS2 characters among pairs of taxa, and (3 the relation between CBCs, hCBCs, CBC clades, and the taxonomic level of organisms was investigated in detail. Results High sequence and length conservation allowed the generation of an ITS2 consensus secondary structure, and introduction of a novel numbering system of ITS2 nucleotides and base pairs. Alignments and analyses were based on this structural information, leading to the following results: (1 in the Ulvales, the presence of a CBC is not linked to any particular taxonomic level, (2 most CBC 'clades' sensu Coleman are paraphyletic, and should rather be termed CBC grades. (3 the phenetic approach of pairwise comparison of sequences can be misleading, and thus, CBCs/hCBCs must be investigated in their evolutionary context, including homoplasy events (4 CBCs and hCBCs in ITS2 helices evolved independently, and we found no evidence for a CBC that originated via a two-fold hCBC substitution. Conclusions Our case study revealed several discrepancies between ITS2

  4. Flora béntica y reproducción de las algas Batophora spp. (Chlorophyta: Dasycladaceae de una laguna costera contaminada (Bahía de Chetumal, México

    Directory of Open Access Journals (Sweden)

    L.I Quan-Young

    2006-06-01

    Full Text Available Los componentes de la flora béntica, y mediciones de partes vegetativas y reproductivas de Batophora oerstedii y B. occidentalis (Chlorophyta se registraron en cinco sitios de la costa Oeste de la Bahía de Chetumal, donde se ha registrado la existencia de un gradiente de contaminación orgánica. La colecta de flora se realizó en mayo y Octubre de 1999, meses incluidos en las épocas climáticas de secas y lluvias, respectivamente. Se registraron 40 taxa de vegetación béntica, de los cuales 11 representan nuevos registros para la Bahía de Chetumal, y 6 para el Caribe Mexicano. Especies de Enteromorpha estuvieron presentes en ambientes ricos en materia orgánica, tanto de origen urbano, como natural. En los desagües de la Bahía de Chetumal existen especies indicadoras de contaminación, pero la ausencia de Batophora spp., dominante en esta laguna costera. Los caracteres morfológicos de B. occidentalis y B. oerstedii a lo largo de los cinco sitios de muestreo no reflejaron la presencia de contaminantes. Ambas especies presentaron diferencias significativas en su largo y ancho de gametóforos, y en el diámetro de gametangios. Las diferencias en estrategias reproductivas probablemente ayudan a que B. oerstedii y B. occidentalis puedan coexistir cercanamente en la Bahía de Chetumal.Benthic flora and reproduction of Batophora spp. algae (Chlorophyta: Dasycladaceae in a polluted coastal lagoon (Chetumal Bay, Mexico. The benthic flora, and the vegetative and reproductive characters of the algae Batophora oerstedii and B. occidentalis (Chlorophyta were recorded from five sites of Chetumal Bay, Quintana Roo, Mexico. A sewage gradient has been reported along those sites. Plants were sampled in May and October 1999, which corresponded to dry and rainy seasons, respectively. Forty taxa were found, 11 are new records for the Chetumal Bay, and 6 are new records for the Mexican Caribbean. Enteromorpha species were present in sites known as rich in

  5. Phenotypic plasticity in Scenedesmus incrassatulus (Chlorophyceae) in response to heavy metals stress.

    Science.gov (United States)

    Peña-Castro, Julián Mario; Martínez-Jerónimo, Fernando; Esparza-García, Fernando; Cañizares-Villanueva, Rosa Olivia

    2004-12-01

    The microalgae genus Scenedesmus is commonly found in freshwater bodies, wastewater facilities and water polluted with heavy metals. Phenotypic plasticity in Scenedesmus has been documented in response to a wide variety of conditions; however, heavy metals have not been comprehensively documented as phenotypic plasticity inducers. In this study, we report the phenotypic plasticity of Scenedesmus incrassatulus (a non-spiny, four-cell coenobium forming species) in response to EC(50) value of copper, cadmium and hexavalent chromium. S. incrassatulus was grown in batch cultures in the presence of each metal. Chlorophyll-a content, cell size, parameters derived from the schematic energy-flux model for photosystem II, and morphotype expressions were recorded. Divalent cation metals induced unicellular forms, and hexavalent chromium produced out-of-shape coenobia corresponding to various stages of autospore formation. The changes induced by divalent metals were interpreted as phenotypic plasticity, because they were always associated to population doublings and were reversible when toxicant pressure was removed (only for Cu). Copper was the best inductor of unicellular forms and also affected significantly all the photosynthetic parameters measured. The developed morphotypes could confer ecological advantages to S. incrassatulus in metal stressed environments.

  6. Time Course Exo-Metabolomic Profiling in the Green Marine Macroalga Ulva (Chlorophyta for Identification of Growth Phase-Dependent Biomarkers

    Directory of Open Access Journals (Sweden)

    Taghreed Alsufyani

    2017-01-01

    Full Text Available The marine green macroalga Ulva (Chlorophyta lives in a mutualistic symbiosis with bacteria that influence growth, development, and morphogenesis. We surveyed changes in Ulva’s chemosphere, which was defined as a space where organisms interact with each other via compounds, such as infochemicals, nutrients, morphogens, and defense compounds. Thereby, Ulva mutabilis cooperates with bacteria, in particular, Roseovarius sp. strain MS2 and Maribacter sp. strain MS6 (formerly identified as Roseobacter sp. strain MS2 and Cytophaga sp. strain MS6. Without this accompanying microbial flora, U. mutabilis forms only callus-like colonies. However, upon addition of the two bacteria species, in effect forming a tripartite community, morphogenesis can be completely restored. Under this strictly standardized condition, bioactive and eco-physiologically-relevant marine natural products can be discovered. Solid phase extracted waterborne metabolites were analyzed using a metabolomics platform, facilitating gas chromatography-mass spectrometry (GC-MS and liquid chromatography-mass spectrometry (LC-MS analysis, combined with the necessary acquisition of biological metadata. Multivariate statistics of the GC-MS and LC-MS data revealed strong differences between Ulva’s growth phases, as well as between the axenic Ulva cultures and the tripartite community. Waterborne biomarkers, including glycerol, were identified as potential indicators for algal carbon source and bacterial-algal interactions. Furthermore, it was demonstrated that U. mutabilis releases glycerol that can be utilized for growth by Roseovarius sp. MS2.

  7. Isolation, expression and characterization of rbcL gene from Ulva prolifera J. Agardh (Ulvophyceae, Chlorophyta)

    Science.gov (United States)

    Shao, Zhanru; Li, Wei; Guo, Hui; Duan, Delin

    2015-12-01

    Ulva prolifera is a typical green alga in subtidal areas and can grow tremendously fast. A highly efficient Rubisco enzyme which is encoded by UpRbcL gene may contribute to the rapid growth. In this study, the full-length UpRbcL open reading frame (ORF) was identified, which encoded a protein of 474 amino acids. Phylogenetic analysis of UpRbcL sequences revealed that Chlorophyta had a closer genetic relationship with higher plants than with Rhodophyta and Phaeophyta. The two distinct residues (aa11 and aa91) were presumed to be unique for Rubisco catalytic activity. The predicted three-dimensional structure showed that one α/β-barrel existed in the C-terminal region, and the sites for Mg2+ coordination and CO2 fixation were also located in this region. Gene expression profile indicated that UpRbcL was expressed at a higher level under light exposure than in darkness. When the culture temperature reached 35°C, the expression level of UpRbcL was 2.5-fold lower than at 15°C, and the carboxylase activity exhibited 13.8-fold decrease. UpRbcL was heterologously expressed in E. coli and was purified by Ni2+ affinity chromatography. The physiological and biochemical characterization of recombinant Rubisco will be explored in the future.

  8. Inhibition of growth of Ulva expansa (chlorophyta) by ultraviolet-B radiation

    International Nuclear Information System (INIS)

    Grobe, C.W.; Murphy, T.M.

    1994-01-01

    We examined the effect of ultraviolet-B radiation (UV-B, 290-320 nm) on the growth rate of the intertidal marine alga Ulva expansa (Setch.) S ampersand G. (Chlorophyta). Segments of thallus collected from a natural population were grown in outdoor seawater tanks. Combinations of UV-B-opaque screens, UV-B transparent screens, and UV-B lamps were used to investigate the effects of solar UV-B and solar plus supplemental UV-B on the growth of these segments. Growth was measured by changes in segment surface area, damp weight, and dry weight. Growth rates of segments were inhibited under both solar UV-B and solar plus supplemental UV-B treatments. Growth rates were also inhibited by high levels of photosynthetically active radiation, independent of UV-B fluence. These results indicate that increases in UV-B resulting from further ozone depletion will have a negative impact on the growth of this alga. 32 refs., 5 figs., 2 tabs

  9. Detection of Genetic Variations in Marine Algae Ulva lactuca (Chlorophyta Induced by Heavy Metal Pollutants

    Directory of Open Access Journals (Sweden)

    Basel Saleh

    2015-09-01

    Full Text Available Ulva lactuca (Chlorophyta green macroalgae has been successfully used as bioindicator for heavy metals pollution in ecosystems. Random amplified microsatellite polymorphism (RAMP marker was employed to investigate genetic DNA pattern variability in green U. lactuca 5 days after exposure to Cu, Pb, Cd and Zn heavy metals stress. Genomic template stability (GTS% value was employed as a qualitative DNA changes measurement based on RAMP technique. In this respect, estimated GTS% value was recorded to be 65.215, 64.630, 59.835 and 59.250% for Pb, Cu, Cd and Zn treatment, respectively. Moreover, genetic similarity (GS induced by the above heavy metals was also evaluated to measure genetic distance between algae treated plants and their respective control. In this respect, estimated GS values generated by RAMP marker ranged between 0.576 (between control and Zn treatment - 0.969 (for both case; between Pb and Cu and between Cd and Zn treatment with an average of 0.842. Based upon data presented herein based on variant bands number (VB, GTS% and GS values; the present study could be suggested that Pb and Cu followed similar tendency at genomic DNA changes. Similar finding was also observed with Cd and Zn ions. Thereby, RAMP marker successfully highlighted DNA change patterns induced by heavy metals stress.

  10. The complete chloroplast and mitochondrial genomes of the green macroalga Ulva sp. UNA00071828 (Ulvophyceae, Chlorophyta.

    Directory of Open Access Journals (Sweden)

    James T Melton

    Full Text Available Sequencing mitochondrial and chloroplast genomes has become an integral part in understanding the genomic machinery and the phylogenetic histories of green algae. Previously, only three chloroplast genomes (Oltmannsiellopsis viridis, Pseudendoclonium akinetum, and Bryopsis hypnoides and two mitochondrial genomes (O. viridis and P. akinetum from the class Ulvophyceae have been published. Here, we present the first chloroplast and mitochondrial genomes from the ecologically and economically important marine, green algal genus Ulva. The chloroplast genome of Ulva sp. was 99,983 bp in a circular-mapping molecule that lacked inverted repeats, and thus far, was the smallest ulvophycean plastid genome. This cpDNA was a highly compact, AT-rich genome that contained a total of 102 identified genes (71 protein-coding genes, 28 tRNA genes, and three ribosomal RNA genes. Additionally, five introns were annotated in four genes: atpA (1, petB (1, psbB (2, and rrl (1. The circular-mapping mitochondrial genome of Ulva sp. was 73,493 bp and follows the expanded pattern also seen in other ulvophyceans and trebouxiophyceans. The Ulva sp. mtDNA contained 29 protein-coding genes, 25 tRNA genes, and two rRNA genes for a total of 56 identifiable genes. Ten introns were annotated in this mtDNA: cox1 (4, atp1 (1, nad3 (1, nad5 (1, and rrs (3. Double-cut-and-join (DCJ values showed that organellar genomes across Chlorophyta are highly rearranged, in contrast to the highly conserved organellar genomes of the red algae (Rhodophyta. A phylogenomic investigation of 51 plastid protein-coding genes showed that Ulvophyceae is not monophyletic, and also placed Oltmannsiellopsis (Oltmannsiellopsidales and Tetraselmis (Chlorodendrophyceae closely to Ulva (Ulvales and Pseudendoclonium (Ulothrichales.

  11. Carotenogénesis de cinco cepas del alga Dunaliella sp. (Chlorophyceae aisladas de lagunas hipersalinas de Venezuela

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    Miguel Guevara

    2005-09-01

    . (Chlorophyceae isolated from Venezuelan hypersaline lagoons. We evaluated discontinuous cultures (Algal medium at 0.5 mM of NaNO3 , and 27% NaCl of five strains of Dunaliella sp. isolated from Venezuelan hypersaline lagoons (Araya, Coche, Peonía, Cumaraguas, and Boca Chica and one strain from a reference collection (Dunaliella salina, LB1644. Cultures were maintained to 25±1 °C, with constant aeration, photoperiod 12:12, and two light intensities (195 and 390 µE.m-2 .s-1 during 30 days. Cell count was recorded on a daily basis using a Neubaüer camera. Totals of chlorophyll a and carotenoids were measured at the end of the experiment. The largest cellular densities were measured during the smallest light intensities. The strain with the largest cellular density was isolated from Boca Chica (8 x10(6 and 2.5 x10(6 cel.ml-1 a 390 and 195µE.m-2 .s-1, respectively. The increment of light intensity produced a significant reduction of growth rates in all strains. Totals of carotenoids by volume were as large as 390 µE.m-2 .s-1. Strains LB1644, from Coche and Araya were those that produced the largest amount of carotenoids (38.4; 32.8 and 21.0 µg.ml-1 , respectively. Differences total carotenoids by cell between treatments were significant. The largest concentration was 390 µE.m-2 .s-1 . The strains LB1644 and Coche produced the highest values of carotenes (137.14 and 106.06 pg.cel-1, respectively. Differences in the relation carotenoid:chlorophyll a between the strains at various light intensities was significant. Strains LB1644 presented the largest value of the relation carotenoids:chlorophyll a (20:1 at 195 µE.m-2 .s-1. No significant differences were detected in the strain Coche (15:1. All the other strains showed relations lower than one. Our results suggest that the strains of Coche and Araya show potential to be used in the biotechnology of carotenoids production. Rev. Biol. Trop. 53(3-4: 331-337. Epub 2005 Oct 3.

  12. Morphological features of the species of the genus Chlamydomonas s.l. (Chlorophyta from various molecular clades

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    Maria N. Pavlovska

    2012-03-01

    Full Text Available The morphology of 78 authentic strains from 5 clades into culture condition was investigated. The complex of phenotype features was established. Such features as: type of mucilage and their origin, mucilage collapse under methylene blue, saving papilla and stigma in not motile stage, extracellular matrix formation inside cell wall, the way of sporangium break, pyrenoid and stigma habit before cell division, cell shape, chloroplast morphology. Diagnostic features for determination of taxa on clades level are discussed.

  13. Pseudoderbesia, nuevo género de algas marinas (Bryopsidaceae, Chlorophyta Pseudoderbesia, nuevo género de algas marinas (Bryopsidaceae, Chlorophyta

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    Calderon Eduardo

    1991-06-01

    Full Text Available Se aislaron cuatro clones de Pseudoderbesia y se mantuvieron como cultivos unialgales: dos provenientes de la Costa Colombiana del Caribe (P. arbuscula y dos de las Islas Canarias en el Océano Atlántico (Pseudoderbesia sp.. Aunque se conoce solo la fase gametofítica, hay razones suficientes para el establecimiento de un nuevo género. Se describe y discute el crecimiento, variabilidad, producción bajo condiciones de cultivo. Se sugiere la posibilidad que ciertas especies de Derbesia que poseen ramificación dicotómica y filamentos gradualmente atenuados, como D. fastigiata, D. attenuata y D. padinae, sean realmente miembros de Pseudoderbesia. Pseudoderbesia is described as a new genus within the Bryopsidaceae. Four clones of Pseudoderbesia were isolated and kept as unialgal cultures: two from the Caribbean coast of Colombia (P. arbuscula and two from the Canary Islands, Atlantic Ocean (Pseudoderbesia sp.. Although only the gametophytic phase is known, it is distinct enough for the establishement of a new genus. Growth, variability and swarmer production, under culture conditions, are described and discussed. It is suggested, that some little known species of Derbesia with dichotomous branching and gradually attenuated filaments, like D. fastigiata, D. attenuata and D. padinae, could actually be members of Pseudoderbesia.

  14. Chloroplast DNA sequence of the green alga Oedogonium cardiacum (Chlorophyceae: Unique genome architecture, derived characters shared with the Chaetophorales and novel genes acquired through horizontal transfer

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    Lemieux Claude

    2008-06-01

    Full Text Available Abstract Background To gain insight into the branching order of the five main lineages currently recognized in the green algal class Chlorophyceae and to expand our understanding of chloroplast genome evolution, we have undertaken the sequencing of chloroplast DNA (cpDNA from representative taxa. The complete cpDNA sequences previously reported for Chlamydomonas (Chlamydomonadales, Scenedesmus (Sphaeropleales, and Stigeoclonium (Chaetophorales revealed tremendous variability in their architecture, the retention of only few ancestral gene clusters, and derived clusters shared by Chlamydomonas and Scenedesmus. Unexpectedly, our recent phylogenies inferred from these cpDNAs and the partial sequences of three other chlorophycean cpDNAs disclosed two major clades, one uniting the Chlamydomonadales and Sphaeropleales (CS clade and the other uniting the Oedogoniales, Chaetophorales and Chaetopeltidales (OCC clade. Although molecular signatures provided strong support for this dichotomy and for the branching of the Oedogoniales as the earliest-diverging lineage of the OCC clade, more data are required to validate these phylogenies. We describe here the complete cpDNA sequence of Oedogonium cardiacum (Oedogoniales. Results Like its three chlorophycean homologues, the 196,547-bp Oedogonium chloroplast genome displays a distinctive architecture. This genome is one of the most compact among photosynthetic chlorophytes. It has an atypical quadripartite structure, is intron-rich (17 group I and 4 group II introns, and displays 99 different conserved genes and four long open reading frames (ORFs, three of which are clustered in the spacious inverted repeat of 35,493 bp. Intriguingly, two of these ORFs (int and dpoB revealed high similarities to genes not usually found in cpDNA. At the gene content and gene order levels, the Oedogonium genome most closely resembles its Stigeoclonium counterpart. Characters shared by these chlorophyceans but missing in members

  15. Polyols and UV-sunscreens in the Prasiola-clade (Trebouxiophyceae, Chlorophyta) as metabolites for stress response and chemotaxonomy.

    Science.gov (United States)

    Hotter, Vivien; Glaser, Karin; Hartmann, Anja; Ganzera, Markus; Karsten, Ulf

    2018-04-01

    In many regions of the world, aeroterrestrial green algae of the Trebouxiophyceae (Chlorophyta) represent very abundant soil microorganisms, and hence their taxonomy is crucial to investigate their physiological performance and ecological importance. Due to a lack in morphological features, taxonomic and phylogenetic studies of Trebouxiophycean algae can be a challenging task. Since chemotaxonomic markers could be a great assistance in this regard, 22 strains of aeroterrestrial Trebouxiophyceae were chemically screened for their polyol-patterns as well as for mycosporine-like amino acids (MAAs) in their aqueous extracts using RP-HPLC and LC-MS. d-sorbitol was exclusively detected in members of the Prasiolaceae family. The novel MAA prasiolin and a related compound ("prasiolin-like") were present in all investigated members of the Prasiola-clade, but missing in all other tested Trebouxiophyceae. While prasiolin could only be detected in field material directly after extraction, the "prasiolin-like" compound present in the other algae was fully converted into prasiolin after 24 h. These findings suggest d-sorbitol and prasiolin-like compounds are suitable chemotaxonomic markers for the Prasiolaceae and Prasiola-clade, respectively. Additional UV-exposure experiments with selected strains show that MAA formation and accumulation can be induced, supporting their role as UV-sunscreen. © 2018 The Authors Journal of Phycology published by Wiley Periodicals, Inc. on behalf of Phycological Society of America.

  16. Polissacarídeos sulfatados isolados das clorofíceas Caulerpa racemosa e Caulerpa cupressoides – extração, fracionamento e atividade anticoagulante =Sulfated polysaccharides isolated from Caulerpa racemosa and Caulerpa cupressoides (Chlorophyceaes – extraction, fractionation and anticoagulant activity

    Directory of Open Access Journals (Sweden)

    José Ariévilo Gurgel Rodrigues

    2010-04-01

    in 0.1 M sodium acetate buffer (pH 5.0 containing 5 mM cysteine and 5 mM EDTA, followed by fractionation on ion exchange DEAE-cellulose column with NaCl gradient. The obtained fractions were analyzed by 0.5% agarose gel electrophoresis and the anticoagulant activity measured by the activated partial thromboplastin time (APTT using normal human plasma, and compared to a standard heparin curve (193 IU mg-1. Similar chromatographic profiles of SP were shown on both species, butwith distinct mobility patterns, when the SP fractions were compared by electrophoresis. SP eluted with 0.75 M of NaCl modified the APTT, whose anticoagulant activities were only 21.23 and 24.36 IU mg-1 for C. racemosa and C. cupressoides, respectively. Therefore, anticoagulant SP isolated from chlorophyceaes showed effects inferior to heparin, and comparative studies of these molecules are also suggested as auxiliary tools in the identification of algae of the same genus.

  17. A Molecular Survey of Ulva (Chlorophyta) in Temperate Australia Reveals Enhanced Levels of Cosmopolitanism.

    Science.gov (United States)

    Kirkendale, Lisa; Saunders, Gary W; Winberg, Pia

    2013-02-01

    The green algal genus Ulva includes a speciose group of marine macroalgae inhabiting shallow seas worldwide. Although algal blooms in Asia highlight the opportunistic nature of several "nuisance" species, recent research clearly reveals important positive benefits of Ulva. Applied research requires accurate, reliable, and rapid identification, however, identification of Ulva spp. has met with con-siderable difficulty. Consequently, many have turned to molecular markers to aid in taxonomy. Previous studies of plants and algae have relied heavily on ITS and rbcL. Recently, tufA has been presented as a suitable barcoding gene to facilitate species-level identification of green macroalgae and it is used here to explore the diversity of Ulva spp. in temperate Australia. Ninety Ulva specimens collected from 38 sites across five states were sequenced for this gene region with exemplars from each genetic group also sequenced for rbcL to test for congruence. Collections of Australian Ulva spp. were compared to samples from Asia and North America and exhibited trends consistent with recent studies in terms of species relationships. Results support an overwhelmingly cosmopolitan flora in temperate Australia that contrasts with other Australasian surveys of Ulva that report a greater number of endemics and new species. Four new records, as well as numerous range extensions for taxa already known from the country, are documented. Evidence for three nonindigenous Ulva species in temperate Australia is discussed. © 2012 Phycological Society of America.

  18. Biodiesel synthesis via transesterification of lipid Chlorophyta cultivated in walne rich carbon medium using KOH/Zeolite catalyst

    Science.gov (United States)

    Dianursanti, Hayati, Siti Zahrotul; Putri, Dwini Normayulisa

    2017-11-01

    Microalgae from the Chlorophyta division such as Nannochloropsis oculata and Chlorella vulgaris are highly potential to be developed as biodiesel feedstocks because they have a high oil content up to 58%. Biodiesel is produced by transesterification of triglycerides and alcohols with the aid of homogeneous catalysts such as KOH. However, the use of KOH catalysts produces soaps in the biodiesel synthesis. Heterogeneous catalysts are known to solve this problem. One of them is natural zeolite. Zeolite can be used as a catalyst and as a support catalyst. Loading KOH on the zeolite surface is expected to increase alkalinity in KOH/Zeolite catalysts so as to increase the activity of KOH/Zeolite catalyst in transesterification of triglyceride with methanol. In this experimental lipid of microalgae will be used for produced biodiesel via transesterification reaction with methanol and KOH/Zeolite as a catalyst heterogeneous at 60 °C for 3h and utilized catalyst modificated KOH/Zeolite with variation 0.5 M, 1 M and 1.5 M KOH. The modified zeolite was then analyzed by XRF, XRD and BET. The result showed that the yield of biodiesel from lipid N.oculata was 81,09% by 0.5KOH/Zeolite catalyst, 86,53% by 1KOH/Zeolite catalyst, 1,5KOH/Zeolite and 88,13% by 1.5KOH/Zeolit, while the biodiesel produced from lipid C.vulgaris was 59.29% by 0.5KOH/Zeolite, 82.27% by 1KOH/Zeolite and 83.72% by 1.5KOH/Zeolite.

  19. Purification and photobiochemical profile of photosystem 1 from a high-salt tolerant, oleaginous Chlorella (Trebouxiophycaea, Chlorophyta).

    Science.gov (United States)

    McConnell, Michael D; Lowry, David; Rowan, Troy N; van Dijk, Karin; Redding, Kevin E

    2015-06-01

    The eukaryotic green alga Chlamydomonas reinhardtii has been studied extensively within the biofuel industry as a model organism, as researchers look towards algae to provide chemical feedstocks (i.e., lipids) for the production of liquid transportation fuels. C. reinhardtii, however, is unsuitable for high-level production of such precursors due to its relatively poor lipid accumulation and fresh-water demand. In this study we offer insight into the primary light harvesting and electron transfer reactions that occur during phototropic growth in a high-salt tolerant strain of Chlorella (a novel strain introduced here as NE1401), a single-celled eukaryotic algae also in the phylum Chlorophyta. Under nutrient starvation many eukaryotic algae increase dramatically the amount of lipids stored in lipid bodies within their cell interiors. Microscopy and lipid analyses indicate that Chlorella sp. NE1401 may become a superior candidate for algal biofuels production. We have purified highly active Photosystem 1 (PS1) complexes to study in vitro, so that we may understand further the photobiochemisty of this promising biofuel producer and how its characteristics compare and contrast with that of the better understood C. reinhardtii. Our findings suggest that the PS1 complex from Chlorella sp. NE1401 demonstrates similar characteristics to that of C. reinhardtii with respect to light-harvesting and electron transfer reactions. We also illustrate that the relative extent of the light state transition performed by Chlorella sp. NE1401 is smaller compared to C. reinhardtii, although they are triggered by the same dynamic light stresses.

  20. Taxonomic significance of micromorphology and dimensions of oospores in the genus Chara L., Charales, Chlorophyta

    Directory of Open Access Journals (Sweden)

    Mandal D.K.

    2004-01-01

    Full Text Available Oospore wall ornamentation patterns as revealed by scanning electron microscopy (SEM provide important taxonomic characters in the Charales. The present study illustrates inter- and intra-specific variations in the oospore wall ornamentation of five species of Chara, including eight intra-specific taxa. The type variety and form of C. globularis shows pusticular elevations with pores at the base of the elevation. The variety and form aspera of C. globularis shows a porous oospore wall, and the oospore is provided with a ribbon which bears nearly granular ornamentation. The type form of C. setosa has a granular oospore wall. The three forms of C. braunii show a similar type of ornamentation and support their placement under a single species. Chara corallina has a roughened oospore wall. Oospore dimensions studied at the population level are another feature included in the present study. The oospore dimension data (length, width fossa-breadth, number of striae at the population level were analyzed statistically, and the results show species-specificity of these parameters. The significance of oospore wall ornamentation and dimensions are discussed simultaneously with morphological features.

  1. Interactions between marine facultative epiphyte Chlamydomonas sp. (Chlamydomonadales, Chlorophyta) and ceramiaceaen algae (Rhodophyta).

    Science.gov (United States)

    Klochkova, Tatyana A; Cho, Ga Youn; Boo, Sung Min; Chung, Ki Wha; Kim, Song Ja; Kim, Gwang Hoon

    2008-07-01

    Previously unrecorded marine Chlamydomonas that grew epiphytic on ceramiaceaen algae was collected from the western coast of Korea and isolated into a unialgal culture. The isolate was subjected to 18S rDNA phylogenetic analysis as well as ultrastructure and life cycle studies. It had an affinity with the marine Chlamydomonas species and was less related to freshwater/terrestrial representatives of this genus. It had flagella shorter than the cell body two-layered cell wall with striated outer surface and abundant mucilaginous material beneath the innermost layer and no contractile vacuoles. This alga grew faster in mixed cultures with ceramiaceaen algae rather than in any tested unialgal culture condition; the cells looked healthier and zoosporangia and motile flagellated vegetative cells appeared more often. These results suggested that this Chlamydomonas might be a facultative epiphyte benefiting from its hosts. Several ceramiaceaen algae were tested as host plants. Meanwhile, cell deformation or collapse of the whole thallus was caused to Aglaothamnion byssoides, and preliminary study suggested that a substance released from Chlamydomonas caused the response. This is first report on harmful epiphytic interactions between Chlamydomonas species and red ceramiaceaen algae.

  2. Growth rate and calcium carbonate accumulation of Halimeda macrolobaDecaisne (Chlorophyta: Halimedaceae in Thai waters

    Directory of Open Access Journals (Sweden)

    Jaruwan Mayakun

    2014-08-01

    Full Text Available Halimeda macroloba Decaisne can utilize the CO2 used for carbon fixation in photosynthesis and use bicarbonate as the main carbon source for calcification. Although Halimeda has been recognized as a carbon sink species, the calcium accumulation of Halimeda species in Thai waters remain poorly understood. In this study, the highest density of H. macroloba was 26 thalli/m2 and Halimeda quickly produced 1-2 new segments/thallus/day or 20.1 mg dry weight/thallus/day. Its calcium carbonate accumulation rate was 16.6 mg CaCO3 /thallus/day, or 82.46 % per thallus. In Thailand, however, only three scientific papers of growth rate and CaCO3 accumulation rate of H. macroloba have been found and collected. Of these records, the mean density was 26-104 thalli/m2 . The growth rate of H. macroloba was around 1-2 mg dry weight/day and the CaCO3 accumulation rate varied around 41-91%. Thus, Halimeda has a great potential to decrease the carbon dioxide concentration in the ocean.

  3. Who is in there? Exploration of endophytic bacteria within the siphonous green seaweed Bryopsis (Bryopsidales, Chlorophyta.

    Directory of Open Access Journals (Sweden)

    Joke Hollants

    Full Text Available Associations between marine seaweeds and bacteria are widespread, with endobiotic bacterial-algal interactions being described for over 40 years. Also within the siphonous marine green alga Bryopsis, intracellular bacteria have been visualized by electron microscopy in the early '70s, but were up to now never molecularly analyzed. To study this partnership, we examined the presence and phylogenetic diversity of microbial communities within the cytoplasm of two Bryopsis species by combining fluorescence in situ hybridization (FISH, denaturing gradient gel electrophoresis (DGGE and 16S rRNA gene clone libraries. Sequencing results revealed the presence of Arcobacter, Bacteroidetes, Flavobacteriaceae, Mycoplasma, Labrenzia, Phyllobacteriaceae and Xanthomonadaceae species. Although the total diversity of the endobiotic communities was unique to each Bryopsis culture, Bacteroidetes, Mycoplasma, Phyllobacteriaceae, and in particular Flavobacteriaceae bacteria, were detected in several Bryopsis samples collected hundreds of kilometres apart. This suggests that Bryopsis closely associates with well-defined endophytic bacterial communities of which some members possibly maintain an endosymbiotic relationship with the algal host.

  4. Gametangial characteristics in the sexual reproduction of Halimeda macroloba Decaisne (Chlorophyta: Halimedaceae

    Directory of Open Access Journals (Sweden)

    Jaruwan Mayakun1

    2012-04-01

    Full Text Available Halimeda macroloba Decaisne is a reef builder that provides habitats for many marine organisms and is importantfor the production of calcium carbonate sediments. This species is one of the most common and abundant algae in tropicalregions of the Indo-Pacific Ocean. However, the trigger for reproduction of H. macroloba is not well understood. We haveexamined some environmental factors that might trigger reproduction and determined the gametangial characteristics of H.macroloba. The peak seasonal reproduction of H. macroloba occurred within only a 3-month period (May-July. Nutrientand salinity were found to have triggered reproduction. Gametangial clusters were produced along the outer margin of segmentsand the gametophores had a long stipe and were dichotomously branched at their distal end. Divided and sessilegametangia were observed. This description of the variable gametangial morphology of H. macroloba is reported for the firsttime.

  5. First and second line mechanisms of cadmium detoxification in the lichen photobiont Trebouxia impressa (Chlorophyta)

    International Nuclear Information System (INIS)

    Sanita di Toppi, L.; Pawlik-Skowronska, B.; Vurro, E.; Vattuone, Z.; Kalinowska, R.; Restivo, F.M.; Musetti, R.; Skowronski, T.

    2008-01-01

    'First line' defence mechanisms, such as phytochelatin biosynthesis, and 'second line' mechanisms, such as stress protein induction, were investigated in cadmium-exposed cells of Trebouxia impressa Ahmadjian, a green microalgal species that is a common photobiont of the lichen Physcia adscendens (Fr.) H. Olivier. When T. impressa cells were exposed to 0, 9 and 18 μM Cd for 6, 18 and 48 h, glutathione and phytochelatins efficiently protected the cells against Cd damage. By contrast, the highest Cd concentration (36 μM) at the longest exposure-time (48 h) caused marked drops in glutathione and phytochelatin content, several types of ultrastructural damage, and decreases in cell density and total chlorophyll concentration. In this case, induction of stress proteins was observed, but only long after the induction of phytochelatins. Thus, stress proteins could represent a 'second line' mechanism to counteract Cd stress, activated when there is a decline in the 'first line' mechanism of Cd detoxification given by phytochelatins. - Trebouxia impressa photobionts protect themselves against cadmium stress by means of phytochelatins and stress proteins

  6. First and second line mechanisms of cadmium detoxification in the lichen photobiont Trebouxia impressa (Chlorophyta)

    Energy Technology Data Exchange (ETDEWEB)

    Sanita di Toppi, L. [Dipartimento di Biologia Evolutiva e Funzionale, viale G.P. Usberti 11/A, Universita di Parma, 43100 Parma (Italy)], E-mail: luigi.sanitaditoppi@unipr.it; Pawlik-Skowronska, B. [Centre for Ecological Research, Polish Academy of Sciences, Experimental Station, Niecala 18/3, 20080 Lublin (Poland); Vurro, E. [Dipartimento di Biologia Evolutiva e Funzionale, viale G.P. Usberti 11/A, Universita di Parma, 43100 Parma (Italy); Vattuone, Z. [Dipartimento di Biologia Evolutiva e Funzionale, viale G.P. Usberti 11/A, Universita di Parma, 43100 Parma (Italy); Centre for Ecological Research, Polish Academy of Sciences, Experimental Station, Niecala 18/3, 20080 Lublin (Poland); Kalinowska, R. [Centre for Ecological Research, Polish Academy of Sciences, Experimental Station, Niecala 18/3, 20080 Lublin (Poland); Restivo, F.M. [Dipartimento di Genetica, Biologia dei Microrganismi, Antropologia, Evoluzione, viale G.P. Usberti 11/A, Universita di Parma, 43100 Parma (Italy); Musetti, R. [Dipartimento di Biologia Applicata alla Difesa delle Piante, via delle Scienze 208, Universita di Udine, 33100 Udine (Italy); Skowronski, T. [Centre for Ecological Research, Polish Academy of Sciences, Experimental Station, Niecala 18/3, 20080 Lublin (Poland)

    2008-01-15

    'First line' defence mechanisms, such as phytochelatin biosynthesis, and 'second line' mechanisms, such as stress protein induction, were investigated in cadmium-exposed cells of Trebouxia impressa Ahmadjian, a green microalgal species that is a common photobiont of the lichen Physcia adscendens (Fr.) H. Olivier. When T. impressa cells were exposed to 0, 9 and 18 {mu}M Cd for 6, 18 and 48 h, glutathione and phytochelatins efficiently protected the cells against Cd damage. By contrast, the highest Cd concentration (36 {mu}M) at the longest exposure-time (48 h) caused marked drops in glutathione and phytochelatin content, several types of ultrastructural damage, and decreases in cell density and total chlorophyll concentration. In this case, induction of stress proteins was observed, but only long after the induction of phytochelatins. Thus, stress proteins could represent a 'second line' mechanism to counteract Cd stress, activated when there is a decline in the 'first line' mechanism of Cd detoxification given by phytochelatins. - Trebouxia impressa photobionts protect themselves against cadmium stress by means of phytochelatins and stress proteins.

  7. Mechanisms of metal tolerance in marine macroalgae, with emphasis on copper tolerance in Chlorophyta and Rhodophyta.

    Science.gov (United States)

    Moenne, Alejandra; González, Alberto; Sáez, Claudio A

    2016-07-01

    Green and red macroalgae are closely related organisms, and with terrestrial plants, and constitute the base of marine food webs in coastal ecosystems. Green and red seaweeds, as all living organisms, require essential metals, such as copper, iron, zinc, which can act as co-factors for several proteins and enzymes; however, these metals in excess can induce stress and impair cell viability. Most important negative effects of metal excess are related to the induction of an oxidative stress condition, characterized by the over-accumulation of Reactive Oxygen Species (ROS). In this respect, copper, abundant in wastewaters disposed to coastal environments from domestic and industrial activities, has been one of the most studied metals. Different investigations have provided evidence that green and red macroalgae display several defenses against copper excess to prevent, or at least reduce, stress and damage, among which are cellular exclusion mechanisms, synthesis of metal-chelating compounds, and the activation of the antioxidant system. Most important defense mechanisms identified in green and red seaweed involve: metal-binding to cell wall and epibionts; syntheses of metallothioneins and phytochelatins that accumulate in the cytoplasm; and the increase in the activity of antioxidant enzymes such as superoxide dismutase, ascorbate peroxidase, glutathione peroxidase and catalase, and greater production of antioxidant metabolites as glutathione and ascorbate in organelles and the cytoplasm. In this review, we go through historical records, latest advances, and pending tasks aiming to expand our current knowledge on defense mechanisms to copper excess in green and red macroalgae, with emphasis on biochemical and molecular aspects. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. In vitro exposure of Ulva lactuca Linnaeus (Chlorophyta) to gasoline - Biochemical and morphological alterations.

    Science.gov (United States)

    Pilatti, Fernanda Kokowicz; Ramlov, Fernanda; Schmidt, Eder Carlos; Kreusch, Marianne; Pereira, Débora Tomazi; Costa, Christopher; de Oliveira, Eva Regina; Bauer, Cláudia M; Rocha, Miguel; Bouzon, Zenilda Laurita; Maraschin, Marcelo

    2016-08-01

    Refined fuels have considerable share of pollution of marine ecosystems. Gasoline is one of the most consumed fuel worldwide, but its effects on marine benthic primary producers are poorly investigated. In this study, Ulva lactuca was chosen as a biological model due to its cosmopolitan nature and tolerance to high levels and wide range of xenobiotics and our goal was to evaluate the effects of gasoline on ultrastructure and metabolism of that seaweed. The experimental design consisted of in vitro exposure of U. lactuca to four concentrations of gasoline (0.001%, 0.01%, 0.1%, and 1.0%, v/v) over 30 min, 1 h, 12 h, and 24 h, followed by cytochemical, SEM, and biochemical analysis. Increase in the number of cytoplasmic granules, loss of cell turgor, cytoplasmic shrinkage, and alterations in the mucilage were some of the ultrastructural alterations observed in thalli exposed to gasoline. Decrease in carotenoid and polyphenol contents, as well as increase of soluble sugars and starch contents were associated with the time of exposure to the xenobiotic. In combination, the results revealed important morphological and biochemical alterations in the phenotype of U. lactuca upon acute exposure to gasoline. This seaweed contain certain metabolites assigned as candidates to biomarkers of the environmental stress investigated and it is thought to be a promise species for usage in coastal ecosystems perturbation monitoring system. In addition, the findings suggest that U. lactuca is able to metabolize gasoline hydrocarbons and use them as energy source, acting as bioremediator of marine waters contaminated by petroleum derivatives. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. ALIEN MARINE SPECIES OF LIBYA: FIRST INVENTORY AND NEW RECORDS IN EL-KOUF NATIONAL PARK (CYRENAICA AND THE NEIGHBOURING AREAS

    Directory of Open Access Journals (Sweden)

    H. BAZAIRI

    2013-10-01

    Full Text Available The presence of marine alien species in El-Kouf National Park and the neighbouring areas was assessed using a compilation of available information and observations, a field survey conducted on October 2010 in the framework of the MedMPAnet project and results of further monitoring during June and September 2012. A total of 9 alien species were reported: the Rhodophyta Asparagopsis taxiformis (Delile Trevisan de Saint-Léon, the Chlorophyta Caulerpa racemosa var. cylindracea (Sonder Verlaque, Huisman & Boudouresque, the crab Percnon gibbesi (H. Milne-Edwards, 1853 and the fishes Fistularia commersonii Rüppell, 1838, Siganus luridus (Rüppell, 1829, Siganus rivulatus Forsskål, 1775, Pempheris vanicolensis Cuvier, 1831, Lagocephalus sceleratus (Gmelin, 1789 and Sphyraena flavicauda Rüppell, 1838. Several of them were until now unknown for the National Park. The list of alien marine species of Libya is updated and discussed. Until now 63 marine aliens species were recorded along the Libyan coasts. These include 3 Foraminifera, 3 Ochrophyta, 5 Rhodophyta, 5 Chlorophyta, 1 Magnoliophyta, 11 Arthropoda, 13 Mollusca, 1 Echinodermata and 21 Chordata. Among these Non Indigenous Species, 43 are known as established along the Libyan coast including 8 invasive, 11 casual, 6 questionable, 3 cryptogenic and 1 unknown. An in-depth study of the marine organisms would substantially increase the number of alien species occurring in Libya. Monitoring of marine assemblages of MPAs is a valuable opportunity to go further into the knowledge of native and introduced species.

  10. The importance of light and photoperiod in sexual reproduction and geographical distribution in the green snow alga, Chloromonas sp.-D (Chlorophyceae, Volvocales)

    Science.gov (United States)

    Hoham, Ronald W.; Marcarelli, Amy M.; Rogers, Haldre S.; Ragan, Michael D.; Petre, Benjamin M.; Ungerer, Michael D.; Barnes, Joseph M.; Francis, David O.

    2000-12-01

    The effects of premating light regimes on sexual reproduction and the production of spherical cells in Chloromonas sp.-D, a unicellular green snow alga, were studied using cross-mating strains 582C and 582D isolated from snowpacks associated with mixed hardwood- softwood forests in Whetstone Gulf State Park, Tughill Plateau, NY. Two pre-acclimation regimes were used, Vita-Lite as controls (530- 700 nm peak) and blue light as experimentals (430- 460 nm peak) prior to the mating experiments. In blue light, an increase in the number of matings and spherical cells (spheres) produced in the life cycle was observed as the photoperiod increased. This implies that longer photoperiods of blue light are more optimal for sexual reproduction in Chloromonas sp.-D than shorter ones. Under Vita-Lite, there was a significant increase in the number of matings and spheres with the extended 20 : 4 photoperiod compared with the shorter 14 : 10 photoperiod. Under blue light, significantly more matings and spheres occurred than under Vita-Lite using the same irradiance level of 95µmol photons m-2 s-1 (photosynthetically active radiation [PAR] of 400- 700 nm) for the 14 : 10 and 20 : 4 photoperiods. The results of these experiments suggest that Chloromonas sp.-D, known only from the Tughill Plateau, NY, is not reproducing optimally at this site where it grows and reproduces under an approximate 14 : 10 photoperiod in early April. However, in the upper 10 cm of snow in the Tughill Plateau, a blue light irradiance level of 95µmol photons m-2 s-1 occurs, which is optimal for this species. When these conditions are combined with a 14 : 10 photoperiod, the Tughill Plateau appears to be sub-optimal for mating and production of spherical cells. Since Chloromonas sp.-D does not appear to have a dependence on a dark cycle, this would allow it to expand its geographical distribution. It may reproduce more optimally under blue light (95µmol photons m-2 s-1) with an extended photoperiod (>20 : 4

  11. Regulation of gametogenesis and zoosporogenesis in Ulva linza (Chlorophyta: comparison with Ulva mutabilis and potential for laboratory culture

    Directory of Open Access Journals (Sweden)

    Eleanor Fay Vesty

    2015-01-01

    Full Text Available Green Ulvophyte macroalgae represent attractive model systems for understanding growth, development and evolution. They are untapped resources for food, fuel and high-value compounds, but can also form nuisance blooms. To fully analyse green seaweed morphogenesis, controlled laboratory-based culture of these organisms is required. To date, only a single Ulvophyte species, Ulva mutabilis Føyn, has been manipulated to complete its whole life cycle in laboratory culture and to grow continuously under axenic conditions. Such cultures are essential to address multiple key questions in Ulva development and in algal-bacterial interactions. Here we show that another Ulva species, U. linza, with a broad geographical distribution, has the potential to be grown in axenic culture similarly to U. mutabilis. Ulva linza can be reliably induced to sporulate (form gametes and zoospores in the laboratory, by cutting the relevant thallus tissue into small pieces and removing extracellular inhibitors (sporulation and swarming inhibitors. The germ cells work as an ideal feed stock for standardized algae cultures.The requirement of U. linza for bacterial signals to induce its normal morphology (particularly of the rhizoids appears to have a species-specific component. The axenic cultures of these two species pave the way for future comparative studies of algal-microbial interactions.

  12. High levels of intra- and inter-individual polymorphism in the rDNA ITS1 of Caulerpa racemosa (Chlorophyta)

    NARCIS (Netherlands)

    Fama, P; Olsen, JL; Stam, WT; Procaccini, G

    2000-01-01

    The coenocytic green alga Caulerpa racemosa colonized the Mediterranean some time after the opening of the Suez Canal in 1869. For most of the past century it has remained confined to the southeastern Mediterranean, but over the past several years the species has been reported in abundance along the

  13. Bacteria-induced morphogenesis of Ulva intestinalis and Ulva mutabilis (Chlorophyta): a contribution to the lottery theory.

    Science.gov (United States)

    Ghaderiardakani, Fatemeh; Coates, Juliet C; Wichard, Thomas

    2017-08-01

    The green marine macroalgae of the class Ulvophyceae (Ulvophytes) are common algae distributed worldwide particularly in intertidal areas, which play a key role in aquatic ecosystems. They are potentially valuable resources for food, animal feed and fuel but can also cause massive nuisance blooms. Members of Ulvaceae, like many other seaweeds, harbour a rich diversity of epiphytic bacteria with functions related to host growth and morphological development. In the absence of appropriate bacterially derived signals, germ cells of the genus Ulva develop into 'atypical' colonies consisting of undifferentiated cells with abnormal cell walls. This paper examines the specificity of bacteria-induced morphogenesis in Ulva, by cross-testing bacteria isolated from several Ulva species on two Ulva species, the emerging model system Ulva mutabilis and the prominent biofouler species Ulva intestinalis. We show that pairs of bacterial strains isolated from species other than U. mutabilis and U. intestinalis can fully rescue axenic plantlets generated either from U. mutabilis or U. intestinalis gametes. This laboratory-based study demonstrates that different compositions of microbial communities with similar functional characteristics can enable complete algal morphogenesis and thus supports the 'competitive lottery' theory for how symbiotic bacteria drive algal development. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Regulation of gametogenesis and zoosporogenesis in Ulva linza (Chlorophyta): comparison with Ulva mutabilis and potential for laboratory culture

    Science.gov (United States)

    Vesty, Eleanor F.; Kessler, Ralf W.; Wichard, Thomas; Coates, Juliet C.

    2015-01-01

    Green Ulvophyte macroalgae represent attractive model systems for understanding growth, development, and evolution. They are untapped resources for food, fuel, and high-value compounds, but can also form nuisance blooms. To fully analyze green seaweed morphogenesis, controlled laboratory-based culture of these organisms is required. To date, only a single Ulvophyte species, Ulva mutabilis Føyn, has been manipulated to complete its whole life cycle in laboratory culture and to grow continuously under axenic conditions. Such cultures are essential to address multiple key questions in Ulva development and in algal–bacterial interactions. Here we show that another Ulva species, U. linza, with a broad geographical distribution, has the potential to be grown in axenic culture similarly to U. mutabilis. U. linza can be reliably induced to sporulate (form gametes and zoospores) in the laboratory, by cutting the relevant thallus tissue into small pieces and removing extracellular inhibitors (sporulation and swarming inhibitors). The germ cells work as an ideal feed stock for standardized algae cultures. The requirement of U. linza for bacterial signals to induce its normal morphology (particularly of the rhizoids) appears to have a species-specific component. The axenic cultures of these two species pave the way for future comparative studies of algal–microbial interactions. PMID:25674100

  15. Identification of metallophores and organic ligands in the chemosphere of the marine macroalga Ulva (Chlorophyta and at land-sea interfaces

    Directory of Open Access Journals (Sweden)

    Thomas Wichard

    2016-07-01

    Full Text Available The roles of organic matter in seawater have often been discussed from the aspect of metal toxicity and bioavailability in seawater. In fact, organic ligands, as part of the organic matter, can work as a trace metal ion buffer system. At the same time, however, the release of well-defined metal chelators as exudates by, for example, marine bacteria is necessary to compete with natural metal complexes and sustain the metal acquisition required for several processes including nitrogen fixation. The identification, isolation and structure elucidation of chelators is, thus, essential to our understanding of metal stress management in the natural habitat and role of these chelators on cellular process. The isolation of an organic ligand from its chemosphere is a challenging task. The purpose of this paper is, therefore, to give an additional perspective on how the effective application of stable isotope pairs of a metal of interest (both cations and oxoanions combined with mass spectrometric analyses can pave the way to discovering new organic ligands (i.e. metallophores and the chelating characteristics of dissolved organic matter (DOM: Pairs of isotopes, such as 54Fe and 58Fe (or any other pair of available isotopes of a given metal, can be used to create easily detectable unique isotopic signatures in mass spectra when they are bound by chelators. The identification of organic ligands is outlined for a proposed model system of mutualistic interactions between the green macroalga Ulva (Chlorophyta and associated bacteria, as well as discussed briefly for DOM along land-sea gradients.

  16. Unraveling the Photoprotective Response of Lichenized and Free-Living Green Algae (Trebouxiophyceae, Chlorophyta to Photochilling Stress

    Directory of Open Access Journals (Sweden)

    Fátima Míguez

    2017-07-01

    Full Text Available Lichens and free-living terrestrial algae are widespread across many habitats and develop successfully in ecosystems where a cold winter limits survival. With the goal of comparing photoprotective responses in free-living and lichenized algae, the physiological responses to chilling and photochilling conditions were studied in three lichens and their isolated algal photobionts together as well as in a fourth free-living algal species. We specifically addressed the following questions: (i Are there general patterns of acclimation in green algae under chilling and photochilling stresses? (ii Do free-living algae exhibit a similar pattern of responses as their lichenized counterparts? (iii Are these responses influenced by the selection pressure of environmental conditions or by the phylogenetic position of each species? To answer these questions, photosynthetic fluorescence measurements as well as pigment and low molecular weight carbohydrate pool analyses were performed under controlled laboratory conditions. In general, photochemical efficiency in all free-living algae decreased with increasing duration of the stress, while the majority of lichens maintained an unchanged photochemical activity. Nevertheless, these patterns cannot be generalized because the alga Trebouxia arboricola and the lichen Ramalina pollinaria (associated with Trebouxia photobionts both showed a similar decrease in photochemical efficiency. In contrast, in the couple Elliptochloris bilobata-Baeomyces rufus, only the algal partner exhibited a broad physiological performance under stress. This study also highlights the importance of the xanthophyll cycle in response to the studied lichens and algae to photochilling stress, while the accumulation of sugars was not related to cold acclimation, except in the alga E. bilobata. The differences in response patterns detected among species can be mainly explained by their geographic origin, although the phylogenetic position should

  17. New data on distribution, morphology and ecology of Oedogonium capillare Kützing ex Hirn (Oedogoniales, Chlorophyta in Poland

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    Marta Pikosz

    2015-12-01

    Full Text Available Algological investigations were focused on taxonomy, chorology and ecology of threatened filamentous green alga species in Poland. Studies on Oedogonium capillare Kützing ex Hirn growing in large quantities in association with Cladophora rivularis (Linnaeus Hoek in pond were conducted. The aim of these studies was to describe the distribution, ecology and morphology of O. capillare as part of a more comprehensive study of this filamentous green alga. It is the eighth record in Poland for O. capillare. Filaments of O. capillare were grown over a wide pH range (7.3-9.6 and in high variability of nutrients. Vegetative cells, oogonia and antheridia were observed, which allowed taxonomic identification. O. capillare occurs in eutrophic waters which requires protection of its habitat.

  18. Chemical compositions of the marine algae Gracilaria salicornia (Rhodophyta) and Ulva lactuca (Chlorophyta) as a potential food source.

    Science.gov (United States)

    Tabarsa, Mehdi; Rezaei, Masoud; Ramezanpour, Zohreh; Waaland, Joseph Robert

    2012-09-01

    The nutritional compositions of two edible red (Gracilaria salicornia) and green (Ulva lactuca) seaweeds were determined to evaluate their possible uses as potential food ingredients. In general, these species contained limited amounts of lipids ranging between 0.99 and 2.00 g 100 g(-1) dry weight) and considerably high amount of minerals, especially in G. salicornia (38.91 g 100 g(-1) d.w.). The crude protein values varied between 9.58 and 10.69 g 100 g(-1) d.w. Amounts for total amino acids were 889.78 ± 22.64 mg g(-1) protein d.w. in G. salicornia and 543.3 ± 15.14 mg g(-1) protein d.w. in U. lactuca. The most abundant fatty acids were C12:0, C16:0, C20:4 ω6 and C22:5 ω3, in addition to C18:1 in G. salicornia. Both seaweed species were balanced sources of ω3 and ω6 fatty acids with a ratio of ω6/ω3 that varied between 1.2 and 1.17. Between the seaweeds investigated, high levels of K (2414.02-11 380.06 mg 100 g(-1) d.w.) were observed and the amounts of Ca, Na and Fe were higher than those reported for land plants. Thus, G. salicornia and U. lactuca may be utilised as value-added products for human nutrition purposes. Copyright © 2012 Society of Chemical Industry.

  19. Characteristic carotenoids in some phytobenthos species in the coastal area of the Adriatic Sea

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    Bazyli Czeczuga

    2014-01-01

    Full Text Available The author investigated the presence of various carotcnoids in some phytobenthos species (20 species representative of Chlorophytn, Phaeophyta and Rhodophyta from the coast of the Adriatic Sea. The presence of following carotenoids has been determined 1 in Chlorophyta lycopene, α-, β-, γ- , ε-carotene, β-cryptoxanthin, lutein, lutein epoxide, zeaxanthin, antheraxanthin, neoxanthin, violaxanthin, siphonein and astaxanthin esier; 2 in Phorophyta: α-, β-, γ- , ε- carotene, zeaxanthin, antheraxanthin, diataxanthin, fucoxanthin, fucoxanthol, neoxanthin, violaxanthin and rhodoxanthin-like: 3 in Rhodophyta α-, β-, γ-carotene,α-, β-,cryptoxanthin, lutein lutein epoxide, zeaxanthin, anthcraxanthin, mutatoxanthin, fucoxanthin neoxanthin and violaxanthin The total carotenoid content ranged from 1.197 ( Cystoseira corniculata to 16 748 mg g-1 dry weight (Chaetomorpha aerea.

  20. Two algal species of Volvox L. with their taxonomy and ecology from West Bengal, India

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    Nilu Halder

    2016-08-01

    Full Text Available The present paper was communicated with the taxonomic description and ecology of two species of the genus Volvox L. viz. Volvox aureus Ehr. and Volvox globator L. under the order Volvocales of class Chlorophyceae. They are freshwater and planktonic phycoflora. The colony of former species was comparatively smaller (340 µm than the later (480 µm whereas, somatic cells were found slightly larger in the former species in comparison to later species. Both were colonial, multicellular, greenish and formed dots like appearances in the water bodies and, exhibited phototactic movements. These two species were being reported first time from Hooghly of West Bengal, India. The ecological study showed that they preferred to grow in alkaline water (pH 7.3-7.5 with slight high organic nutrient contents (NO3 -N: PO4 3- ratios: 0.25-0.35: 0.30-0.32 mg/l. This study also revealed that higher total alkalinity values (174.0-184.0 mg/l were favorable for their developments and their maximum growth noticed in summer in aquatic ecosystems.

  1. Use of alternative media and different types of recipients in a laboratory culture of Ankistrodesmus gracilis (Reinsch Korshikov (Chlorophyceae - doi: 10.4025/actascibiolsci.v33i3.8046 Use of alternative media and different types of recipients in a laboratory culture of Ankistrodesmus gracilis (Reinsch Korshikov (Chlorophyceae - doi: 10.4025/actascibiolsci.v33i3.8046

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    Flávia de Almeida Berchielli

    2011-07-01

    Full Text Available A laboratory culture of Ankistrodesmus gracilis algae was evaluated by studying the biology of the species and its chemical composition in a traditional medium (CHU12 and in two alternative culture media, NPK (20-5-20 and macrophyte (Eichhornia crassipes + NPK, in three different types of recipients (fiberglass, carboy and plastic bag. First peak in the growth curve of Ankistrodesmus gracilis occurred on the ninth day in macrophyte + NPK medium (74.16 x 105 cells mL-1 in a fiberglass recipient. However, highest density (p 12 (122.87 x 105 cells mL-1 in a plastic bag on the twelfth day. Cell density was over 70 x 105 cells mL-1 starting on the twelfth day. Growth rate of A. gracilis was similar (p > 0.05 in culture media in the three recipients. Protein and fiber were similar (p > 0.05 in the treatments, but lipids were higher (p -1 in NPK (p A. gracilis cultured in three types of recipients. Costs are low, occupying less space when cultured in plastic bags and in the laboratory.A laboratory culture of Ankistrodesmus gracilis algae was evaluated by studying the biology of the species and its chemical composition in a traditional medium (CHU12 and in two alternative culture media, NPK (20-5-20 and macrophyte (Eichhornia crassipes + NPK, in three different types of recipients (fiberglass, carboy and plastic bag. First peak in the growth curve of Ankistrodesmus gracilis occurred on the ninth day in macrophyte + NPK medium (74.16 x 105 cells mL-1 in a fiberglass recipient. However, highest density (p 12 (122.87 x 105 cells mL-1 in a plastic bag on the twelfth day. Cell density was over 70 x 105 cells mL-1 starting on the twelfth day. Growth rate of A. gracilis was similar (p > 0.05 in culture media in the three recipients. Protein and fiber were similar (p > 0.05 in the treatments, but lipids were higher (p -1 in NPK (p A. gracilis cultured in three types of recipients. Costs are low, occupying less space when cultured in plastic bags and in the

  2. Use of alternative media and different types of recipients in a laboratory culture of Ankistrodesmus gracilis (Reinsch Korshikov (Chlorophyceae = Utilização de meios alternativos e diferentes tipos de recipientes no cultivo de Ankistrodesmus gracilis (Reinsch Korshikov (Chlorophyceae em laboratório.

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    Lucia Helena Sipauba-Tavares

    2011-07-01

    Full Text Available A laboratory culture of Ankistrodesmus gracilis algae was evaluated by studying the biology of the species and its chemical composition in a traditional medium (CHU12 and in two alternative culture media, NPK (20-5-20 and macrophyte (Eichhornia crassipes + NPK, in three different types of recipients (fiberglass, carboy and plastic bag. First peak in the growth curve of Ankistrodesmus gracilis occurred on the ninth day in macrophyte + NPK medium (74.16 x 105 cells mL-1 in a fiberglass recipient. However, highest density (p 0.05 in culture media in the three recipients. Protein and fiber were similar (p > 0.05 in the treatments, but lipids were higher (p O objetivo do estudo foi avaliar os aspectos biológicos e a composição química da alga Ankistrodesmus gracilis em laboratório utilizando um meio tradicional (CHU12 e dois meios alternativos, NPK (20-5-20 e macrófita (Eichhornia crassipes + NPK em três diferentes tipos de recipientes (cuba de fibra de vidro translúcido, garrafões e saco plástico. O primeiro pico de densidade celular de Ankistrodesmus gracilis ocorreu no nono dia da curva de crescimento em meio macrófita+NPK (74,16 x 105 células mL-1 no recipiente de fibra de vidro, porém a maior densidade (p 0,05 nos três recipientes e meios de cultivo. Os teores de proteína e fibra foram similares (p > 0,05 nos tratamentos utilizados, já os de lipídios foram mais elevados (p < 0,05 no meio NPK. Os teores médios de nitrato, amônia, fósforo total e ortofosfato estiveram acima de 1 mg L-1 no meio NPK (p < 0,01. Os resultados obtidos neste estudo indicam a possibilidade do uso de meios alternativos como o NPK e macrophyte +NPK para o cultivo de A. gracilis em larga escala cultivados nos três tipos de recipientes, porém, em saco plástico o custo é baixo e ocupa menos espaço em cultivo de laboratório.

  3. Carotenoids, Phenolic Compounds and Tocopherols Contribute to the Antioxidative Properties of Some Microalgae Species Grown on Industrial Wastewater

    DEFF Research Database (Denmark)

    Safafar, Hamed; van Wagenen, Jonathan Myerson; Møller, Per

    2015-01-01

    sp., and Desmodesmus sp. (Chlorophyta), were screened for their antioxidant properties using different in vitro assays. Natural antioxidants, including pigments, phenolics, and tocopherols, were measured in methanolic extracts of microalgae biomass. Highest and lowest concentrations of pigments......This study aimed at investigating the potential of microalgae species grown on industrial waste water as a new source of natural antioxidants. Six microalgae from different classes, including Phaeodactylum sp. (Bacillariophyceae), Nannochloropsis sp. (Eustigmatophyceae), Chlorella sp., Dunaniella......, phenolic compounds, and tocopherols were found in Desmodesmus sp. and Phaeodactylum tricornuotom microalgae species, respectively. The results of each assay were correlated to the content of natural antioxidants in microalgae biomass. Phenolic compounds were found as major contributors to the antioxidant...

  4. Determination of selected elements in red, brown and green seaweed species for monitoring pollution in the coastal environment of Ghana

    International Nuclear Information System (INIS)

    Serfor-Armah, Y.; Ghana Atomic Energy Commission, Legon-Accra; Ghana University, Legon-Accra; Carboo, D.; Akuamoah, R.K.; Chatt, A.

    2006-01-01

    The concentrations of 23 elements, namely Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hf, Hg, I, K, La, Mg, Mn, Na, Ni, Sc, Sm, V, and Zn, in seven Rhodophyta (red), three Phaeophyta (brown) and five Chlorophyta (green) seaweed species from different areas along the coast of Ghana were determined using instrumental neutron activation analysis (INAA). These species can be potentially used as biomonitors. The INAA method involved irradiations using thermal and epithermal neutrons at the Dalhousie University SLOWPOKE-2 Reactor (DUSR) facility followed by conventional and anti-coincidence γ-ray spectrometry. The precision in terms of relative standard deviation was within ±4%. The accuracy of the methods was evaluated by analyzing four reference materials. Our results were within ±3% of the certified or information values in all cases. (author)

  5. Strategies to enhance the production of photosynthetic pigments and lipids in chlorophycae species

    Directory of Open Access Journals (Sweden)

    Juan Roberto Benavente-Valdés

    2016-06-01

    Full Text Available Microalgae are a major natural source for a vast array of valuable compounds as lipids, proteins, carbohydrates, pigments among others. Despite many applications, only a few species of microalgae are cultured commercially because of poorly developed of cultivation process. Nowadays some strategies of culture have been used for enhancing biomass and value compounds yield. The most strategies applied to microalgae are classified into two groups: nutrimental and physical. The nutrimental are considered as change in media composition as nitrogen and phosphorous limitation and changes in carbon source, while physical are described as manipulation in operational conditions and external factors such as application of high-light intensities, medium salinity and electromagnetic fields. The exposition to electromagnetic field is a promising technique that can improve the pigments and biomass yield in microalgae culture. Therefore, is important to describe the advantages and applications of the overall process. The aim of this review was to describe the main culture strategies used to improve the photosynthetic and lipids content in chlorophyceae species.

  6. Strategies to enhance the production of photosynthetic pigments and lipids in chlorophycae species.

    Science.gov (United States)

    Benavente-Valdés, Juan Roberto; Aguilar, Cristóbal; Contreras-Esquivel, Juan Carlos; Méndez-Zavala, Alejandro; Montañez, Julio

    2016-06-01

    Microalgae are a major natural source for a vast array of valuable compounds as lipids, proteins, carbohydrates, pigments among others. Despite many applications, only a few species of microalgae are cultured commercially because of poorly developed of cultivation process. Nowadays some strategies of culture have been used for enhancing biomass and value compounds yield. The most strategies applied to microalgae are classified into two groups: nutrimental and physical. The nutrimental are considered as change in media composition as nitrogen and phosphorous limitation and changes in carbon source, while physical are described as manipulation in operational conditions and external factors such as application of high-light intensities, medium salinity and electromagnetic fields. The exposition to electromagnetic field is a promising technique that can improve the pigments and biomass yield in microalgae culture. Therefore, is important to describe the advantages and applications of the overall process. The aim of this review was to describe the main culture strategies used to improve the photosynthetic and lipids content in chlorophyceae species.

  7. Cellulose contents of some abundant Indian seaweed species.

    Science.gov (United States)

    Siddhanta, Arup K; Kumar, Sanjay; Mehta, Gaurav K; Chhatbar, Mahesh U; Oza, Mihir D; Sanandiya, Naresh D; Chejara, Dharmesh R; Godiya, Chirag B; Kondaveeti, Stalin

    2013-04-01

    Crude cellulose as well as alpha- and beta-celluloses were estimated in thirty-four seaweed species of fifteen orders of Chlorophyta, Phaeophyta and Rhodophyta of Indian waters. The greatest yields of crude cellulose and a-cellulose were obtained from Chaetomorpha aerea (approx. 20.0% and 18.5%, respectively), and of beta-cellulose (approx. 3.1%) from Caulerpa imbricata. The lowest crude cellulose, and alpha-and beta-contents were recorded for the calcareous red alga Liagora indica (approx. 0.90%, 0.70% and 0.10%, respectively). There was little variation in cellulose content among the brown algae, while wide variations in the yields were found in the green and red algae. The present work contributes to the repertoire of 67 Indian seaweed species studied to now for their cellulose contents in our laboratory. The combined studies highlight that Chaetomorpha aerea, Acrosiphonia orientalis, Caulerpa taxifolia, Sargassum tenerrimum, Hydroclathrus clathratus and Gelidiella acerosa possess relatively high (> 10%) cellulose contents, which could be of potential utility.

  8. Enzymatic regulation of photosynthetic and light-independent carbon fixation in Laminaria setchellii (Phaeophyta, Ulva lactuca (Chlorophyta and Iridaea cordata (Rhodophyta Regulación enzimática de la fotosíntesis y la fijación de carbono en obscuridad por Laminaria setchellii (Phaeophyta, Ulva lactuca (Chlorophyta e Iridaea cordata (Rhodophyta

    Directory of Open Access Journals (Sweden)

    ALEJANDRO CABELLO-PASINI

    2001-06-01

    carboxikinasa (PEPCK y fosfoenolpiruvato carboxilasa (PEPC en la Phaeophyta Laminaria setchellii, la Chlorophyta Ulva lactuca y la Rhodophyta Iridaea cordata. Los niveles de clorofila-a no variaron en U. lactuca e I. cordata. Sin embargo, los niveles de pigmentos fueron significativamente menores en la región meristemática de L. setchellii probablemente debido a una falta de diferenciación de los cloroplastos de esta región. De una manera similar, la fotosíntesis neta no varió en el talo de U. lactuca e I. cordata, mientras que se incrementó desde el estipe y el meristemo hacia la lámina de L. setchellii. En contraste con la fotosíntesis, la fijación de carbono en oscuridad fue significantemente mayor en la zona meristemática de L. setchellii sugiriendo un mecanismo para la compensación de la incorporación de carbono en tejido fotosintéticamente limitado. La actividad enzimática de RUBISCO y PEPCK se comportó de una manera similar a los procesos carboxilantes in vivo, indicando que la fotosíntesis y la fijación de carbono en oscuridad son reguladas por la actividad de las enzimas carboxilantes a lo largo del talo de L. setchellii

  9. Endangered Species

    Science.gov (United States)

    EPA's Endangered Species Protection Program helps promote recovery of listed species. The ESPP determines if pesticide use in a geographic area may affect any listed species. Find needed limits on pesticide use in Endangered Species Protection Bulletins.

  10. Plankton Community Stability and Its Relationship with Phytoplankton Species Richness in Lake Nansihu, China

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    Wang Tian

    2016-10-01

    Full Text Available The relationship between biodiversity and ecosystem functioning is a central issue in ecology. The insurance hypothesis suggests that biodiversity could improve community productivity and reduce the temporal variability of main ecosystem processes. In the present study, we used a plankton community that was investigated from 2011 to 2014 in Lake Nansihu to test this hypothesis and explore the mechanisms involved. As a result, 138 phytoplankton and 76 zooplankton species were identified in the lake, and their biomasses showed apparent seasonal variations. The average temporal stability index of zooplankton taxa was significantly higher than that of phytoplankton. Complex relationships were observed between the species richness and temporal stability of different phytoplankton taxa: a unimodal relationship for both Cyanophyta and Bacillariophyta; a strong concave relationship for Euglenophyta; and no apparent relationship for both Chlorophyta and total phytoplankton. These relationships were primarily controlled by the portfolio effect; while the effects of overyielding and species asynchrony were relatively weak. Phytoplankton species richness had a significant positive influence on the temporal stability indices of protozoa, Rotifera and total zooplankton, while its influence on Cladocera and copepods was not significant. The dominant mechanisms were found to be ‘trophic overyielding’ and a weak ‘trophic portfolio effect’; however, ‘trophic species asynchrony’ played a minor role. These results demonstrated that the effects of diversity on community stability can be complex in natural ecosystems. In addition, the diversity of phytoplankton not only influenced its own temporal stability, but also affected the stability of zooplankton through trophic interactions.

  11. Ulva ohnoi (Ulvales, Chlorophyta) as a biofilter in IMTA-RAS systems: influence of nitrogen and phosphorous levels in its development

    OpenAIRE

    Cremades Ugarte, Javier; Casais, Eduardo; Oca Baradad, Joan; Masaló Llorà, Ingrid; Jiménez de Ridder, Patrícia; Pintado Valverde, José

    2017-01-01

    The present study aims to gain knowledge about the influence of the concentrations of these nutrients and their possible interactions in the development of Ulva ohnoi, the selected species in this project

  12. Effect of treated sewage on growth of marine algae

    Digital Repository Service at National Institute of Oceanography (India)

    Dhargalkar, V.K.

    Eight algal species belonging to Chlorophyta, Rhodophyta and Phaeophyta were used to assess the effect of different concentrations of secondary treated sewage on their growth. Chlorophyta and Rhodophyta members. Ulva fasciata and Gracilaria...

  13. Ulva and Enteromorpha (Ulvaceae, Chlorophyta) from two sides of the Yellow Sea: analysis of nuclear rDNA ITS and plastid rbcL sequence data

    Science.gov (United States)

    Wang, Jinfeng; Li, Nan; Jiang, Peng; Boo, Sung Min; Lee, Wook Jae; Cui, Yulin; Lin, Hanzhi; Zhao, Jin; Liu, Zhengyi; Qin, Song

    2010-07-01

    Ulvacean green seaweeds are common worldwide; they formed massive green tides in the Yellow Sea in recent years, which caused marine ecological problems as well as a social issue. We investigated two major genera of the Ulvaceae, Ulva and Enteromorpha, and collected the plastid rbcL and nuclear ITS sequences of specimens of the genera in two sides of the Yellow Sea and analyzed them. Phylogenetic trees of rbcL data show the occurrence of five species of Enteromorpha ( E. compressa, E. flexuosa, E. intestinalis, E. linza and E. prolifera) and three species of Ulva ( U. pertusa, U. rigida and U. ohnoi). However, we found U. ohnoi, which is known as a subtropical to tropical species, at two sites on Jeju Island, Korea. Four ribotypes in partial sequences of 5.8S rDNA and ITS2 from E. compressa were also found. Ribotype network analysis revealed that the common ribotype, occurring in China, Korea and Europe, is connected with ribotypes from Europe and China/Japan. Although samples of the same species were collected from both sides of the Yellow Sea, intraspecific genetic polymorphism of each species was low among samples collected worldwide.

  14. Changes in seagrass polychaete assemblages after invasion by Caulerpa racemosa var. cylindracea (Chlorophyta: Caulerpales: community structure, trophic guilds and taxonomic distinctness

    Directory of Open Access Journals (Sweden)

    Antonio Box

    2010-06-01

    Full Text Available A two-year study focusing on the associated polychaete assemblages revealed that the degradation of the Posidonia oceanica seagrass meadows, together with the colonisation of rhizomes by invasive Caulerpa racemosa in the Balearic Islands, have produced important changes in the ecosystem functioning, and have therefore affected the benthic faunal communities. The highest abundance and number of species occurred in C. racemosa from August to December. The species composition of the polychaete assemblage in C. racemosa is similar to that of P. oceanica but abundances of shared species differ between Caulerpa and Posidonia. Abundance, number of species and diversity were positively correlated with C. racemosa biomass. The spatial complexity provided by the network of C. racemosa fronds and stolons seemed to combine with that of the remaining seagrass mat to support a well developed polychaete assemblage. Although invaded meadows harboured significantly modified polychaete assemblages when compared with living P. oceanica meadows, the main impacts seem to be non-harmful (i.e. increased abundance and number of species and mainly affect their seasonal patterns, which is a direct consequence of the corresponding biomass seasonality of C. racemosa.

  15. Molecular evidence for a diverse green algal community growing in the hair of sloths and a specific association with Trichophilus welckeri (Chlorophyta, Ulvophyceae

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    Chiarello Adriano G

    2010-03-01

    Full Text Available Abstract Background Sloths are slow-moving arboreal mammals inhabiting tropical rainforests in Central and South America. The six living species of sloths are occasionally reported to display a greenish discoloration of their pelage. Trichophilus welckeri, a green algal species first described more than a century ago, is widely believed to discolor the animals fur and provide the sloth with effective camouflage. However, this phenomenon has not been explored in any detail and there is little evidence to substantiate this widely held opinion. Results Here we investigate the genetic diversity of the eukaryotic community present in fur of all six extant species of sloth. Analysis of 71 sloth hair samples yielding 426 partial 18S rRNA gene sequences demonstrates a diverse eukaryotic microbial assemblage. Phylogenetic analysis reveals that sloth fur hosts a number of green algal species and suggests that acquisition of these organisms from the surrounding rainforest plays an important role in the discoloration of sloth fur. However, an alga corresponding to the morphological description of Trichophilus welckeri was found to be frequent and abundant on sloth fur. Phylogenetic analysis demonstrated the retention of this alga on the fur of sloths independent of geographic location. Conclusions These results demonstrate a unique diverse microbial eukaryotic community in the fur of sloths from Central and South America. Our analysis streghtens the case for symbiosis between sloths and Trichophilus welckeri.

  16. Strong Endemism of bloom-forming tubular Ulva in Indian West Coast, with description of Ulva paschima Sp. Nov. (Ulvales, Chlorophyta).

    Science.gov (United States)

    Bast, Felix; John, Aijaz Ahmad; Bhushan, Satej

    2014-01-01

    Ulva intestinalis and Ulva compressa are two bloom-forming morphologically-cryptic species of green seaweeds widely accepted as cosmopolitan in distribution. Previous studies have shown that these are two distinct species that exhibit great morphological plasticity with changing seawater salinity. Here we present a phylogeographic assessment of tubular Ulva that we considered belonging to this complex collected from various marine and estuarine green-tide occurrences in a ca. 600 km stretch of the Indian west coast. Maximum Likelihood and Bayesian Inference phylogenetic reconstructions using ITS nrDNA revealed strong endemism of Indian tubular Ulva, with none of the Indian isolates forming part of the already described phylogenetic clades of either U. compressa or U. intestinalis. Due to the straightforward conclusion that Indian isolates form a robust and distinct phylogenetic clade, a description of a new bloom-forming species, Ulva paschima Bast, is formally proposed. Our phylogenetic reconstructions using Neighbor-Joining method revealed evolutionary affinity of this new species with Ulva flexuosa. This is the first molecular assessment of Ulva from the Indian Subcontinent.

  17. Phytoplankton species composition of four ecological provinces in Yellow Sea, China

    Science.gov (United States)

    Li, Xiaoqian; Feng, Yuanyuan; Leng, Xiaoyun; Liu, Haijiao; Sun, Jun

    2017-12-01

    The ecological province based on phytoplankton species composition is important to understanding the interplay between environmental parameters and phytoplankton species composition. The aim of this study was to establish phytoplankton species composition ecological pattern thus elucidate the relationship between environmental factors and the phytoplankton species composition in the ecological provinces. Phytoplankton samples were collected from 31 stations in Yellow Sea (121.00°-125.00°E, 32.00°-39.22°N) in November 2014. The samples were enumerated and identified with the Utermöhl method under an optical inverted microscope-AE2000 with magnifications of 200 × or 400 ×. In the present study, a total of 141 taxa belonging to 60 genera of 4 phyla of phytoplankton were identified, among them 101 species of 45 genera were Bacillariophyta, 36 species of 11 genera were Dinophyta, 3 species of 3 genera were Chrysophyta and 1 species of 1 genera was Chlorophyta. The study area was divided into 4 ecological provinces according to an unsupervised cluster algorithm applied to the phytoplankton biomass. A T-S (Temperature-Salinity) scatter diagram depicted with data of water temperature and salinity defined by environmental provinces matched well with the ecological provinces. The results of Canonical Correspondence Analysis (CCA) indicated that the phytoplankton species composition was mainly correlated with temperature, salinity and silicate concentration in the studied area. A method of establishing ecological provinces is useful to further understanding the environmental effects on the marine phytoplankton species composition and the consequent marine biogeochemistry.

  18. Basicladia chelonum (Collins W.E. Hoffmann et Tilden (Chlorophyta, Cladophorophyceae from Cuba (Caribbean: new observation of the ultrastructure of its vegetative cells

    Directory of Open Access Journals (Sweden)

    Joanna Czerwik-Marcinkowska

    2011-01-01

    Full Text Available Basicladia chelonum (Collins W.E. Hoffmann and Tilden (1930 principally known from North America and Hawaii was recently (2004 found in Cuba (Caribbean from artificial pool growing on shells of musk turtles (Trachemys decussata Gray. Specimens collected in Cuba were subjected to detailed examinations also using a transmission electron microscope. On one hand, these studies confirmed many features of this species previously described by earlier authors in the specimens from Texas. On the other hand, the present studies revealed structures unknown so far (pyrenoid structure, which allowed for new analysis of this species. These investigations also have shown that Basicladia chelonum exhibits close similarity to the genus Cladophora and other representatives of the class Cladophorophyceae. The similarities include : siphonocladous level of organization of thallus, numerous chloroplasts forming a network and other structures. Conversely, the pyrenoid in vegetative cells of Basicladia chelonum distinguishes it markedly from representatives of the genus Cladophora, which have bilenticular pyrenoids divided into two hemispheres by a single thylakoids and each hemisphere is covered by a bowlshaped starch grain (Van Hoek et al. 1995. Since in Cladophora the ultrastructure of the pyrenoid is highly constant and characteristic, this contrasts with the genus Basicladia and, therefore, more firmly establishes position of the latter as an independent unit within Cladophorophyceae.

  19. Invasive Species

    Science.gov (United States)

    Invasive species have significantly changed the Great Lakes ecosystem. An invasive species is a plant or animal that is not native to an ecosystem, and whose introduction is likely to cause economic, human health, or environmental damage.

  20. Seasonal variation in biomass and species composition of seaweeds stranded along Port Okha, northwest coast of India

    Science.gov (United States)

    Thakur, Mukund C.; Reddy, C. R. K.; Jha, Bhavanath

    2008-06-01

    Port Okha coast, which is known for its luxuriant growth of a diverse assemblage of seaweeds on Saurashtra coast, is found to have abundant quantities of seaweeds being drifted and washed ashore every year. Studies conducted for quantifying the stranded seaweeds from May 2004 to April 2005 showed an average biomass value of 3.10 kg fresh wt/m2/month with maximum being 6.60 kg fresh wt/m2 in April. The stranded weeds constituted a total of 62 species during the entire study period. Of this, Rhodophyta ranked high with 26 species followed by Chlorophyta with 22 species and Phaeophyta with 14 species. The stranded seaweeds that were washed ashore provide valuable floristic information about the intertidal and near shore sub-tidal algae of the respective regions. Although natural senescence of seaweeds is one of the major factors, strong currents primarily forced by tides, also contribute to the uprooting and subsequent drifting of seaweeds on to the beach. This ultimately causes changes in floristic features of the existing algal beds.

  1. Comparison of extraction and transesterification methods on the determination of the fatty acid contents of three Brazilian seaweed species

    Directory of Open Access Journals (Sweden)

    Aline P. Martins

    2012-08-01

    Full Text Available Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen J.V. Lamouroux (Rhodophya, Sargassum cymosum C. Agardh (Heterokontophyta, and Ulva lactuca L. (Chlorophyta, comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl. The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

  2. Comparison of extraction and transesterification methods on the determination of the fatty acid contents of three Brazilian seaweed species

    Directory of Open Access Journals (Sweden)

    Aline P. Martins

    2012-06-01

    Full Text Available Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen J.V. Lamouroux (Rhodophya, Sargassum cymosum C. Agardh (Heterokontophyta, and Ulva lactuca L. (Chlorophyta, comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl. The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

  3. The effects of UV radiation on photosynthesis estimated as chlorophyll fluorescence in Zygnemopsis decussata (Chlorophyta growing in a high mountain lake (Sierra Nevada, Southern Spain

    Directory of Open Access Journals (Sweden)

    Mayte MATA

    2009-08-01

    were similar in algae submitted to desiccation/rehydration under PAB and P treatments as they were in the control (submerged algae. The combined effect of desiccation and UVA produced the greatest decrease of photosynthesis in Z. decussata. Thus UVB, in contrast to other species, may support the recovery process. Z. decussata can acclimate to severe stress conditions in this high mountain lake by the photoprotection mechanism induced by UVB radiation through dynamic photoinhibition and the accumulation of phenolic compounds (UV screen and antioxidant substances.

  4. Seasonal variations in biomass and species composition of seaweeds along the northern coasts of Persian Gulf (Bushehr Province)

    Science.gov (United States)

    Dadolahi-Sohrab, A.; Garavand-Karimi, M.; Riahi, H.; Pashazanoosi, H.

    2012-02-01

    This study was carried out to evaluate the seasonal variations of seaweed biomass and species composition at six different sites along the coastal areas in Bushehr Province. Sampling depths varied among sites, from 0.3 to 2.0 m below mean sea level. A total of 37 (i.e., 10 Chlorophyta, 12 Phaeophyta and 15 Rhodophyta) seaweed species were collected. Studies were conducted for quantifying the seaweeds during four seasons from October 2008 until July 2009. During present research, Ulva intestinalis and Cladophora nitellopsis of green, Polycladia myrica, Sirophysalia trinodis and Sargassum angustifolium of brown and Gracilaria canaliculata and Hypnea cervicornis of red seaweeds showed highest biomass in coastal areas of Bushehr Province. The Cheney`s ratio of 2.1 indicated a temperate algal flora to this area. All sites exhibited more than 50% similarity of algal species, indicating a relatively homogenous algal distribution. Total biomass showed the highest value of 3280.7 ± 537.8 g dry wt m - 2 during summer and lowest value of 856.9 ± 92.0 g dry wt m - 2 during winter. During this study, the highest and lowest seaweed biomass were recorded on the site 2 (2473.7 ± 311.0 g dry wt m - 2) and site 5 (856.7 ± 96.8 g dry wt m - 2), respectively.

  5. Antioxidant, antimutagenic and antiproliferative activities in selected seaweed species from Sinaloa, Mexico.

    Science.gov (United States)

    Osuna-Ruiz, Idalia; López-Saiz, Carmen-María; Burgos-Hernández, Armando; Velázquez, Carlos; Nieves-Soto, Mario; Hurtado-Oliva, Miguel A

    2016-10-01

    Context Seaweeds from the Mexican Pacific Ocean have not been evaluated as a source of chemoprotectants. Objective The objective of this study is to evaluate chemopreventive activities of the seaweeds Phaephyceae - Padina durvillaei (Dictyotaceae) - Rodhophyceae - Spyridia filamentosa (Spyridiaceae), Gracilaria vermiculophylla (Gracilariaceae) - and Chlorophyceae - Ulva expansa (Ulvaceae), Codium isabelae (Codiaceae), Rhizoclonium riparium (Cladophoraceae) and Caulerpa sertularioides (Caulerpaceae). Materials and methods Methanol, acetone and hexane seaweed extracts were assessed at 30 and 3 mg/mL on antioxidant capacity (DPPH and ABTS assays), 0.003-3.0 mg/plate on antimutagenic activity against AFB1 using Salmonella typhimurium TA98 and TA100 tester strains in Ames test, and 12.5 to 100 μg/mL on antiproliferative activity on Murine B-cell lymphoma. Phenols, flavonoids and pigments content were also assessed as antioxidant compounds. Results Extraction yield was higher in methanol than in acetone and hexane extracts (6.4, 2.7 and 1.4% dw). Antioxidant capacity was higher in brown and green than in red seaweed species, particularly in P. durvillaei extracted in acetone (EC50  value= 16.9 and 1.56 mg/mL for DPPH and ABTS). Flavonoids and chlorophylls were identified as mainly antioxidant components; particularly in hexane extracts, which were correlated with the antioxidant capacity. Highest mutagenesis inhibition (> 40%) occurred in R. riparium at the lowest concentration assayed (0.003 mg/plate), while highest antiproliferative inhibition (37 and 72% for 12.5 and 25 μg/mL) occurred in C. sertularioides. Discussion and conclusion Flavonoids and chlorophylls explained the chemopreventive activities assessed in S. filamentosa, R. riparium and C. sertularioides. These seaweeds have a high potential as a source of novel chemoprotectants.

  6. Detection of green algae (Chlorophyceae) for the diagnosis of drowning.

    Science.gov (United States)

    Yoshimura, S; Yoshida, M; Okii, Y; Tokiyasu, T; Watabiki, T; Akane, A

    1995-01-01

    The plankton test (generally, diatom test) is one of the methods available to diagnose the cause of death of submerged bodies. The solubilization method using tissue solubilizer Soluene-350 was used in this study to detect not only diatoms but also green algae, based on the fact that the solubilizer does not digest the cell walls of green algae which are made from cellulose. Detection of green algae from organs of submerged cadavers is very informative to determine drowning in fresh water, and also in cases where only few diatoms are detected in the organs.

  7. 'Candidatus Megaira polyxenophila' gen. nov., sp. nov.: considerations on evolutionary history, host range and shift of early divergent rickettsiae.

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    Martina Schrallhammer

    Full Text Available "Neglected Rickettsiaceae" (i.e. those harboured by non-hematophagous eukaryotic hosts display greater phylogenetic variability and more widespread dispersal than pathogenic ones; yet, the knowledge about their actual host range and host shift mechanism is scarce. The present work reports the characterization following the full-cycle rRNA approach (SSU rRNA sequence, specific in situ hybridization, and ultrastructure of a novel rickettsial bacterium, herewith proposed as 'Candidatus Megaira polyxenophila' gen. nov., sp. nov. We found it in association with four different free-living ciliates (Diophrys oligothrix, Euplotes octocarinatus, Paramecium caudatum, and Spirostomum sp., all belonging to Alveolata, Ciliophora; furthermore it was recently observed as intracellular occurring in Carteria cerasiformis and Pleodorina japonica (Chlorophyceae, Chlorophyta. Phylogenetic analyses demonstrated the belonging of the candidate new genus to the family Rickettsiaceae (Alphaproteobacteria, Rickettsiales as a sister group of the genus Rickettsia. In situ observations revealed the ability of the candidate new species to colonize either nuclear or cytoplasmic compartments, depending on the host organism. The presence of the same bacterial species within different, evolutionary distant, hosts indicates that 'Candidatus Megaira polyxenophila' recently underwent several distinct host shifts, thus suggesting the existence of horizontal transmission pathways. We consider these findings as indicative of an unexpected spread of rickettsial infections in aquatic communities, possibly by means of trophic interactions, and hence propose a new interpretation of the origin and phylogenetic diversification of rickettsial bacteria.

  8. Silica gel matrix immobilized Chlorophyta hydrodictyon africanum ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-08-05

    Aug 5, 2015 ... immobilization of 300 mg per gram silica. Maximum immobilization was 400 mg biomass per gram silica. Sorption capacity increased with an increase in initial dye concentration and reached equilibrium within. 30 min. Three models were used to simulate kinetic data and the pseudo–second order model ...

  9. Carotenoids, Phenolic Compounds and Tocopherols Contribute to the Antioxidative Properties of Some Microalgae Species Grown on Industrial Wastewater

    Directory of Open Access Journals (Sweden)

    Hamed Safafar

    2015-12-01

    Full Text Available This study aimed at investigating the potential of microalgae species grown on industrial waste water as a new source of natural antioxidants. Six microalgae from different classes, including Phaeodactylum sp. (Bacillariophyceae, Nannochloropsis sp. (Eustigmatophyceae, Chlorella sp., Dunaniella sp., and Desmodesmus sp. (Chlorophyta, were screened for their antioxidant properties using different in vitro assays. Natural antioxidants, including pigments, phenolics, and tocopherols, were measured in methanolic extracts of microalgae biomass. Highest and lowest concentrations of pigments, phenolic compounds, and tocopherols were found in Desmodesmus sp. and Phaeodactylum tricornuotom microalgae species, respectively. The results of each assay were correlated to the content of natural antioxidants in microalgae biomass. Phenolic compounds were found as major contributors to the antioxidant activity in all antioxidant tests while carotenoids were found to contribute to the 1,1-diphenyl-2-picryl-hydrazil (DPPH radical scavenging activity, ferrous reduction power (FRAP, and ABTS-radical scavenging capacity activity. Desmodesmus sp. biomass represented a potentially rich source of natural antioxidants, such as carotenoids (lutein, tocopherols, and phenolic compounds when cultivated on industrial waste water as the main nutrient source.

  10. Seasonal variations in the biochemical composition of some common seaweed species from the coast of Abu Qir Bay, Alexandria, Egypt

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    Hanan M. Khairy

    2013-05-01

    Full Text Available Variations in protein, carbohydrate, lipid, ash, moisture, fatty acid and aminoacid contents of the seaweeds Ulva lactuca Linnaeus (Chlorophyta,Jania rubens (Linnaeus J.V. Lamouroux and Pterocladia capillacea (S.G. Gmelin Bornet(Rhodophyta were studied seasonally from spring to autumn 2010. The seaweeds were collected from a rocky site near Boughaz El-Maadya on the coast of Abu Qir Bay east of Alexandria, Egypt. Remarkable seasonal variations were recorded in the levels of the studied parameters in the three species. Pterocladia capillacea was characterized by the highest protein andcarbohydrate content throughout the different seasons, whereas Ulva lactuca contained more lipids (4.09 ± 0.2% than J. rubens and P. capillacea. The highest total fatty acids were recorded in J. rubens during the three seasons, while saturated fatty acids were predominant in P. capillacea during spring. This is due mainly to the presence of palmitic acid(C16:0, which made up 74.3% of the saturated fatty acids. The highest level of polyunsaturated fatty acids (PUFA in these algae was measured in J. rubens; DHA (22:6ω3 was the main acid, making up 26.4% of the total fatty acids especiallyduring summer. Proline was the major component of the amino acids in the three algal species, with maximum amounts in U. lactuca.

  11. Carotenoids, Phenolic Compounds and Tocopherols Contribute to the Antioxidative Properties of Some Microalgae Species Grown on Industrial Wastewater

    Science.gov (United States)

    Safafar, Hamed; van Wagenen, Jonathan; Møller, Per; Jacobsen, Charlotte

    2015-01-01

    This study aimed at investigating the potential of microalgae species grown on industrial waste water as a new source of natural antioxidants. Six microalgae from different classes, including Phaeodactylum sp. (Bacillariophyceae), Nannochloropsis sp. (Eustigmatophyceae), Chlorella sp., Dunaniella sp., and Desmodesmus sp. (Chlorophyta), were screened for their antioxidant properties using different in vitro assays. Natural antioxidants, including pigments, phenolics, and tocopherols, were measured in methanolic extracts of microalgae biomass. Highest and lowest concentrations of pigments, phenolic compounds, and tocopherols were found in Desmodesmus sp. and Phaeodactylum tricornuotom microalgae species, respectively. The results of each assay were correlated to the content of natural antioxidants in microalgae biomass. Phenolic compounds were found as major contributors to the antioxidant activity in all antioxidant tests while carotenoids were found to contribute to the 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging activity, ferrous reduction power (FRAP), and ABTS-radical scavenging capacity activity. Desmodesmus sp. biomass represented a potentially rich source of natural antioxidants, such as carotenoids (lutein), tocopherols, and phenolic compounds when cultivated on industrial waste water as the main nutrient source. PMID:26690454

  12. (Annonaceae) species

    African Journals Online (AJOL)

    Aghomotsegin

    2016-03-09

    Mar 9, 2016 ... 2Bioactivity Programme, Natural Products Division, Forest Research Institute Malaysia (FRIM), 52109 Kepong, Selangor. Darul Ehsan, Malaysia. ... The genus Xylopia comprises about 170 species and they are widely .... American Type Culture Collection (ATCC) while VRSA156 and. VISA24 were lab ...

  13. The concept of ecological succession applied to phytoplankton over four consecutive years in five ponds featuring a salinity gradient

    Science.gov (United States)

    Khemakhem, Hajer; Elloumi, Jannet; Moussa, Mahmoud; Aleya, Lotfi; Ayadi, Habib

    2010-06-01

    The distribution of phytoplankton abundance, biomass and species composition coupled with environmental factors and metazooplankton was studied relatively intensively and over a period of four consecutive years in five ponds featuring a gradient of increasing salinity from near to that of sea water to a nine-fold concentration from 2000 to 2003. The results indicate that the physical characteristics of the water (temperature and salinity) were quite similar over the years. Nutrients, which were concentrated in pond A1, decreased with increases in salt concentration. The composition of the phytoplankton community showed strong seasonality. Diatoms dominated in the first ponds A1, A16 and C2-1, followed by dinoflagellates. Chlorophyceae dominated the phytoplankton community in the hypersaline ponds M2 and TS. Cyanobacteriae were relatively abundant in ponds M2 and TS. The highest phytoplankton density and biomass were found in the ponds with the highest salinity due to the proliferation of Dunaliella salina (Chlorophyta: Volvocales). The inter-annual study of phytoplankton succession in the Sfax solar salterns showed slight differences among the years of study due to the stability of the environmental conditions. Phytoplankton communities were permanently primitive, stage 1 - structured as they failed to build complexity because of salt stress which operates for longer and above any other variables. This reduced frequency of disturbance to the existing course of regulation, allowed the community to "mature" from its "primitive" state, rather than experience frequent structural setbacks.

  14. The role of abiotic and biotic environmental factors in shaping epiphyton on common reed in shallow, hydrologically transformed, temperate lakes

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    Toporowska Magdalena

    2018-01-01

    Full Text Available Epiphytic algae are an important group of organisms involved in primary productivity, nutrient cycling, and energy transfer in littoral food webs. However, multifactorial studies conducted on epiphyton on the same substrate across a spectrum of environmental parameters are very limited. Here, we present first complex field study on the role of abiotic and biotic factors in shaping the species richness, diversity, abundance, and biomass composition of epiphyton on common reed in four shallow lakes with different trophic status, water and fish management, and the abundance and structure of potential algal grazers: littoral crustaceans and fish. The obtained results revealed that the algal taxa richness was the lowest in the hypertrophic lake and the highest in the meso-eutrophic lake. Epiphyton abundance (predominated by pennate diatoms and biomass were found to be the highest in eutrophic water bodies. Biomass consisted primarily of diatoms, but we found the seasonal predominance of filamentous Chlorophyta (in the eutrophic lakes and Chlorophyceae (in the meso-eutrophic lake. Redundancy analysis (RDA showed that the frequency of water level fluctuations was the most significant variable in the composition of epiphyton. RDA also revealed the importance of grazing pressure of fish. Thus, in hydrologically transformed lakes, man-made factors may be of great relevance in the development of epiphytic algae.

  15. Biochemical constituents of seaweeds along the Maharashtra coast

    Digital Repository Service at National Institute of Oceanography (India)

    Dhargalkar, V.K.; Jagtap, T.G.; Untawale, A.G.

    Protein, carbohydrate and organic carbon were estimated in 43 marine algal species from different stations along the Maharashtra Coast in India These species showed variation in their biochemical contents Protein varied from 10 to 33% Chlorophyceae...

  16. Heavy metal concentrations in macroalgae species from Sinop coasts of the Southern Black Sea

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    Levent Bat

    2016-10-01

    Full Text Available Objective: To determine the concentrations of Fe, Zn, Ni, Cu, Mn, Pb, Cd and Co in macroalgae from Sinop coasts of the Sounthern Black Sea. Methods: Chlorophyta-green algae (Chaetomorpha spp., Cladophora spp., Ulva linza, Ulva intestinalis, Ulva lactuca, Ulva rigida; Ochrophyta-brown alga [Cystoseira barbata (C. barbata] and Rhodophyta-red algae (Ceramium spp., Corallina panizzoi were collected seasonally in the year 2010 from the upper infralittoral zone of inner harbour, outer harbour, Gerze and Ayancık of Sinop coasts of the Black Sea. The samples were analysed by atomic absorption spectrophotometer in order to determine heavy metal levels in different algal division species along Sinop coasts and to provide information of marine environment quality as marine strategy framework directive is aimed to ensure good environmental status of the seas by 2020 in the European Union. Results: The results showed that metal concentrations in all studied green algae, brown alga and red algae increase in the order: Cd < Co < Ni < Pb < Cu < Zn < Mn < Fe, Cd < Co < Cu < Ni < Pb < Mn < Zn < Fe and Co < Cd < Ni < Cu < Pb < Mn < Zn < Fe, respectively. In all divisions, among the essential elements the highest concentrations exhibited by Fe, in Gerze station- (2328 ± 89 µg/g dry weight in Chaetomorpha spp.; (2143 ± 78 µg/g dry weight in C. barbata and (968 ± 20 µg/g dry weight in Ceramium spp. Conclusions: The highest accumulation of different metals in the analysed algae species were: Fe and Co in Chaetomorpha spp., Zn in C. barbata, Ni and Cu in Ulva linza, Mn in Ulva intestinalis, Pb and Cd in Corallina panizzoi.

  17. Screening of antioxidant activity in microalgae

    Directory of Open Access Journals (Sweden)

    Mariana F.G. Assunção

    2014-06-01

    Both sets of results indicate an interesting antioxidant potential in microalgae belonging to the groups Eustigmatophyceae and Chlorophyceae. Tested species of these groups showed ABTS•+ values comparable to grape and raspberry ethanolic extracts, confirmed also by the DPPH• method.

  18. Bioactivity of marine organisms: Part 7- Effect of seaweed extract on central nervous system

    Digital Repository Service at National Institute of Oceanography (India)

    Kamat, S.Y.; Wahidullah, S.; DeSouza, L.; Naik, C.G.; Ambiye, V.; Bhakuni, D.S.; Jain, S.; Goel, A.K.; Srimal, R.C.

    Alcohol extracts of marine algae (Rhodophyceae, Phaeophyceae and Chlorophyceae) was screened for their effect on central nervous system. Of 69 species investigated 8 appeared biologically active, 6 being CNS stimulant, sites and dates of collection...

  19. Extraction and anticoagulant activity of sulfated polysaccharides from Caulerpa cupressoides var. lycopodium (Vahl C. Agardh (Chlorophyceae = Extração e atividade anticoagulante dos polissacarídeos sulfatados da clorofícea Caulerpa cupressoides var. lycopodium (Vahl C. Agardh = Extração e atividade anticoagulante dos polissacarídeos sulfatados da clorofícea Caulerpa cupressoides var. lycopodium (Vahl C. Agardh.

    Directory of Open Access Journals (Sweden)

    José Ariévilo Gurgel Rodrigues

    2011-04-01

    Full Text Available The reportedly low standard quality of heparin (HEP for use in cardiac surgeries has led to concern in the Brazilian and international markets. Sulfated polysaccharides (SPs from seaweeds have been regarded as promising substitutes for HEP. The aim of this study was to sequentially extract total SPs (TSPs from Caulerpa cupressoides (Chlorophyceae with papain in 100 mM sodium acetate buffer (pH 5.0 containing 5 mM cysteine and 5 mM EDTA, followed byfractionation by ion-exchange chromatography (DEAE-cellulose, and then evaluate the anticoagulant potential of SP fractions by activated partial thromboplastin time (APTT using normal human plasma and compare it to standard HEP (193 IU mg-1. The obtained fractions were chemically characterized by chemical composition and agarose gel electrophoresis. The yield was 4.61%, and three fractions of SP (F I, F II and F III eluted with 0.50, 0.75 and 1.00 M of NaCl,respectively, were observed on chromatography profiles; however, differences in charge densities patterns and degree of resolution among them were revealed by electrophoresis. SPs were capable of modifying APTT only in fractions eluted with 0.75 M of NaCl, whose activities were 23.37 and 25.76 IU mg-1, respectively, and the charge density was prerequisite to activity. Therefore, C. cupressoides is a source of SPs possessing low anticoagulant potential compared to HEP.O baixo padrão de qualidade outrora declarado da heparina (HEP para o uso em cirurgias cardíacas tem levado preocupação nos mercados nacional e internacional. Os polissacarídeos sulfatados (PSs de algasmarinhas têm sido considerados como promissores substitutos para HEP. Objetivou-se a extrair sequencialmente PSs totais (PSTs da clorofícea Caulerpa cupressoides com papaína em tampão acetato de sódio 100 mM (pH 5,0 contendo cisteína 5 mM e EDTA 5 mM, fracionar por cromatografia de troca iônica (DEAE-celulose e avaliar o potencial anticoagulante das frações de PS por meio do

  20. Marine algal flora of submerged Angria Bank (Arabian Sea)

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A.G.; Reddy, C.R.K.; Ambiye, V.

    Submerged Angria Bank was surveyed for the deep water marine algal flora. About 57 species were reported from this bank for the first time. Rhodophyta dominated (30 species) followed by Chlorophyta (18 species) and Phaeophyta (9 species). A few...

  1. An Algal Diet Accelerates Larval Growth of Anopheles gambiae (Diptera: Culicidae) and Anopheles arabiensis (Diptera: Culicidae).

    Science.gov (United States)

    Tuno, N; Kohzu, A; Tayasu, I; Nakayama, T; Githeko, A; Yan, G

    2018-01-21

    The population sizes of Anopheles gambiae Giles (Diptera: Culicidae) and Anopheles arabiensis Patton (Diptera: Culicidae) increase dramatically with the onset of the rainy season in sub-Saharan Africa, but the ecological mechanisms underlying the increases are not well understood. As a first step toward to understand, we investigated the proliferation of algae, the major food of mosquito larvae, in artificial fresh water bodies exposed to sunlight for a short period, and old water bodies exposed to sunlight for a long period, and the effects thereof on the development of these anopheline larvae. We found that an epizoic green algal species of the genus Rhopalosolen (Chlorophyta: Chlorophyceae) proliferated immediately after water freshly taken from a spring was placed in sunlight. This alga proliferated only briefly (for ~10 d) even if the water was repeatedly exposed to sunlight. However, various algal species were observed in water that remained under sunlight for 40 d or longer (i.e., in old water bodies). The growth performance of larvae was higher in sunlight-exposed (alga-rich) water than in shade-stored (alga-poor) water. Stable isotope analysis suggested that these two anopheline species fed on Rhopalosolen algae in fresh water bodies but hardly at all on other algae occurring in the old water bodies. We concluded that freshly formed ground water pools facilitate high production of anopheline species because of the proliferation of Rhopalosolen algae therein, and the increase in the number of such pools in the rainy season, followed by rapid increases in A. gambiae and A. arabiensis numbers. © The Author(s) 2018. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Species concept and speciation

    Directory of Open Access Journals (Sweden)

    Amal Y. Aldhebiani

    2018-03-01

    Full Text Available Defining and recognizing a species has been a controversial issue for a long time. To determine the variation and the limitation between species, many concepts have been proposed. When a taxonomist study a particular taxa, he/she must adopted a species concept and provide a species limitation to define this taxa. In this paper some of species concepts are discussed starting from the typological species concepts to the phylogenetic concept. Positive and negative aspects of these concepts are represented in addition to their application.

  3. Characterization of an UV- and VIS-absorbing, purpurogallin-derived secondary pigment new to algae and highly abundant in Mesotaenium berggrenii (Zygnematophyceae, Chlorophyta), an extremophyte living on glaciers.

    Science.gov (United States)

    Remias, Daniel; Schwaiger, Stefan; Aigner, Siegfried; Leya, Thomas; Stuppner, Hermann; Lütz, Cornelius

    2012-03-01

    Mesotaenium berggrenii is one of few autotrophs that thrive on bare glacier surfaces in alpine and polar regions. This extremophilic alga produces high amounts of a brownish vacuolar pigment, whose chemical constitution and ecological function is largely unknown until now. Field material was harvested to isolate and characterize this pigment. Its tannin nature was determined by photometric methods, and the structure determination was carried out by means of HPLC-MS and 1D- and 2D-NMR spectroscopy. The main constituent turned out to be purpurogallin carboxylic acid-6-O-β-d-glucopyranoside. This is the first report of such a phenolic compound in this group of algae. Because of its broad absorption capacities of harmful UV and excessive VIS radiation, this secondary metabolite seems to play an important role for the survival of this alga at exposed sites. Attributes and abundances of the purpurogallins found in M. berggrenii strongly suggest that they are of principal ecophysiological relevance like analogous protective pigments of other extremophilic microorganisms. To prove that M. berggrenii is a true psychrophile, photosynthesis measurements at ambient conditions were carried out. Sequencing of the 18S rRNA gene of this alpine species and of its arctic relative, the filamentous Ancylonema nordenskiöldii, underlined their distinct taxonomic position within the Zygnematophyceae. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  4. Endangered Species Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of the Endangered Species Act (ESA) is to protect and recover imperiled species and the ecosystems upon which they depend. The U.S. Fish and Wildlife...

  5. Endangered Species Protection Bulletins

    Science.gov (United States)

    Endangered Species Protection Bulletins set forth geographically specific pesticide use limitations for the protection of threatened and endangered (listed) species and their designated critical habitat. Find out how to get and use Bulletins.

  6. National invasive species program

    Science.gov (United States)

    Anna Rinick

    2007-01-01

    The structure and function of the National Invasive Species Council was presented below. The names and contact information for the USDA Invasive Species coordinators as of February 2006 were presented on the next page.

  7. Species choice, provenance and species trials among native Brazilian species

    Energy Technology Data Exchange (ETDEWEB)

    Drumond, M.A.

    1982-01-01

    Six papers from the conference are presented. Drumond, M.A., Potential of species native to the semi-arid tropics, 766-781, (Refs. 18), reports on Anadenanthera macrocarpa, Mimosa species, Schinopsis brasiliensis, Spondias tuberosa, Ziziphus joazeiro, Cnidoscolus phyllacanthus, Bursera leptophleos (leptophloeos), Tabebuia impetiginosa, Astronium urundeuva, and Mimosa caesalpinia. Monteiro, R.F.R., Speltz, R.M., Gurgel, J.T. do A.; Silvicultural performance of 24 provenances of Araucaria angustifolia in Parana, 814-824, (Refs. 8). Pires, C.L. da S., Kalil Filho, A.N., Rosa, P.R.F. da, Parente, P.R., Zanatto, A.C.S.; Provenance trials of Cordia alliodora in the State of Sao Paulo, 988-995, (Refs. 9). Nogueira, J.C.B., Siqueira, A.C.M.F., Garrido, M.A.O., Gurgel Garrido, L.M. do A., Rosa, P.R.F., Moraes, J.L. de, Zandarin, M.A., Gurgel Filho, O.A., Trials of some native species in various regions of the State of Sao Paulo, 1051-1063, (Refs. 9) describes Centrolobium tomentosum, Peltophorum dubium, Tabebuia vellosoi, Cariniana legalis, and Balfourodendron riedelianum. Batista, M.P., Borges, J.F., Franco, M.A.B.; Early growth of a native species in comparison with exotics in northeastern Para, Brazil, 1105-1110, (Refs. 3). Jacaranda copaia is compared with Gmelina arborea, Pinus caribaea various hondurensis, Eucalyptus deglupta, and E. urophylla. Lima, P.C.F., Souza, S.M. de, Drumond, M.A.; Trials of native forest species at Petrolina, Pernambuco, 1139-1148, (Refs. 8), deals with Anadenanthera macrocarpa, Piptadenia obliqua, Pithecellobium foliolosum, Astronium urundeuva, Schinopsis brasiliensis, Cassia excelsa, Caesalpinia pyramidalis, Parkia platycephala, Pseudobombax simplicifolium, Tabebuia impetiginosa, Caesalpinia ferrea, and Aspidosperma pyrifolium. 18 references.

  8. Detection of cryptic species

    International Nuclear Information System (INIS)

    Cockburn, A.F.; Jensen, T.; Seawright, J.A.

    1998-01-01

    Morphologically similar cryptic species are common in insects. In Anopheles mosquitoes morphologically described species are complexes of cryptic species. Cryptic species are of great practical importance for two reasons: first, one or more species of the complex might not be a pest and control efforts directed at the complex as a whole would therefore be partly wasted; and second, genetic (and perhaps biological) control strategies directed against one species of the complex would not affect other species of the complex. At least one SIT effort has failed because the released sterile insect were of a different species and therefore did not mate with the wild insects being targeted. We use a multidisciplinary approach for detection of cryptic species complexes, focusing first on identifying variability in wild populations using RFLPs of mitochondrial and ribosomal RNA genes (mtDNA and rDNA); followed by confirmation using a variety of other techniques. For rapid identification of wild individuals of field collections, we use a DNA dot blot assay. DNA probes can be isolated by differential screening, however we are currently focusing on the sequencing of the rDNA extragenic spacers. These regions are repeated several hundred times per genome in mosquitoes and evolve rapidly. Molecular drive tends to keen the individual genes homogeneous within a species. (author)

  9. Chlorococcales (Algee: Chlorophyceae found in aquatic environments of the Colombian Amazon basin Chlorococcales (Algee: Chlorophyceae found in aquatic environments of the Colombian Amazon basin

    Directory of Open Access Journals (Sweden)

    Núñez Avellaneda Marcela

    1998-06-01

    Full Text Available Ten taxa of algae belonging to the order Chlorococcales are recorded for the first time from the Colombian Amazon basin. Two of these, Nephrocytium limneticum and Sorastrum americanum var. americanum, are recorded for the first time in Colombia.Se registran por primera vez para la Amazonia colombiana 10 taxones de Chlorococcales del fitoplancton y ticoplancton encontrados en algunos lagos del río Amazonas y del río Cotuhé, afluente del río Putumayo. Nephrocytium limneticum y Sorastrum americanum varo americanum son primeros registros para Colombia.

  10. Características populacionais de Microphrys bicornutus (Brachyura, Mithracidae no fital Halimeda opuntia (Chlorophyta, Halimedaceae, em área recifal submetida à visitação humana, em João Pessoa, Paraíba Population characteristics of Microphrys bicornutus (Brachyura, Mithracidae on the phytal Halimeda opuntia (Chlorophyta, Halimedaceae, on reef area submitted to human visitation, in João Pessoa, Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    Jefferson B. Batista

    2009-03-01

    immature animals, and similar size frequency and reproductive period. Sex-ratio, size frequency distribution, and size of the biggest specimens differed from those estimated in others latitudes and habitats for this species. Sex ratio estimation has made evident that independently of maturation stage, males tended to predominate significantly and the proportion of females to decrease with sexual maturation. Without exhibiting influence of the alga biomass, and of the salinity and temperature of the water, significant population variations were associated to the increase of juvenile during rainy periods. The low population density and the largest disproportion of the relationship male: female in Picãozinho subarea with larger flow of people, are suggestive that the trampling of the alga might have induced this population variation.

  11. Support your local species

    DEFF Research Database (Denmark)

    Stärk, Johanna

    Nearly a quarter of all animal species within the European Union are threatened with extinction. Protecting many of these species will require the full spectrum of conservation actions from in-situ to ex-situ management. Holding an estimated 44% of EU Red Listed terrestrial vertebrates, zoos hereby...

  12. New Species of Agaricales

    Science.gov (United States)

    Kim, Yang Sup; Park, Ki Moon; Kim, Wan Gyu; Yoo, Kwan Hee; Park, In Cheol

    2009-01-01

    Clitocybe alboinfundibulliforme sp. nov. is widely distributed in Korea. Volvariella koreana sp. nov. is rarely distributed in Korea. These taxa were occasionally found together at the same place. Both of these species seem to be associated with each other. These two species are fully described and illustrated in this paper. PMID:23983550

  13. (WF n ) species

    Indian Academy of Sciences (India)

    potential, electron affinity, absolute electronegativity and chemical hardness are also evaluated which provide insights into chemical ..... η = 1/2 (IP − EA). (3). Absolute electronegativity measures the ability of species to attract electron and correlates inversely with the proton affinity. The increase in χ of WFn species with the ...

  14. Arctic species resilience

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Forchhammer, Mads C.; Jeppesen, Erik

    the predicted increase in climate variability. Whereas species may show relatively high phenological resilience to climate change per se, the resilience of systems may be more constrained by the inherent dependence through consumer-resource interactions across trophic levels. During the last 15 years...... and resources. This poster will present the conceptual framework for this project focusing on species resilience....

  15. Aquatic species and habitats

    Science.gov (United States)

    Danny C. Lee; James R. Sedell; Bruce E. Rieman; Russell F. Thurow; Jack E. Williams

    1998-01-01

    Continuing human activities threaten the highly prized aquatic resources of the interior Columbia basin. Precipitous declines in native species, particularly Pacific salmon, and a large influx of introduced species have radically altered the composition and distribution of native fishes. Fortunately, areas of relatively high aquatic integrity remain, much of it on...

  16. Chapter 16: Species Diversity

    African Journals Online (AJOL)

    zargaran

    2012-05-03

    May 3, 2012 ... In this survey, the oak gall wasps (Hymenoptera: Cynipidae: Cynipini) were collected from oak forests of West-Azerbaijan Province in six sites, from April to October. Species richness, heterogeneity, evenness and true diversity were measured. Based on the result of this study, 37 of oak gall wasps species ...

  17. Management of invasive species

    DEFF Research Database (Denmark)

    Schou, Jesper Sølver; Jensen, Frank

    In this paper, we conduct a number of cost-benefit analyses to clarify whether the establishment of invasive species should be prevented or the damage of such species should be mitigated after introduction. We use the potential establishment of ragweed in Denmark as an empirical case. The main...... of information externalities, altruistic preferences, possible catastrophic events and ethical considerations....

  18. The Origin of Species

    NARCIS (Netherlands)

    Darwin, Charles

    2005-01-01

    In The Origin of Species Darwin outlined his theory of evolution, which proposed that species had been evolving and differentiating over time under the influence of natural selection. On its publication it became hugely influential, bringing about a seismic shift in the scientific view of humanitys

  19. Occurrence of genus Monostroma (Ulvales, Chlorophyta) from Ratnagiri (Maharashtra)

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A.G.; Agadi, V.V.; Dhargalkar, V.K.

    The occurrence of a genus Monostroma has been recorded from the Shirgaon creek at Ratnagiri along the central west coast of India. The Monostroma sp. was found in the brackish water environment with low salinity, high nutrients and thick mangrove...

  20. (Chlorophyta) biomass production using Moringa oleifera Lam. leaf ...

    African Journals Online (AJOL)

    Chlorella sorokiniana Shih. et Krauss, a unicellular green alga was assayed to assess its to promotion potentials response of aqueous and ethanolic leaf extracts of Moringa oleifera Lam. C. sorokiniana grown in 200 ml aliquots of modified basal medium for two weeks: was treated with the aqueous and ethanolic extracts at ...

  1. Algal diversity of Adada River, Nigeria. I. Chlorophyta (green algae ...

    African Journals Online (AJOL)

    Commercial water tankers collect water and sell to indigenes and towns around the river, hence the need to investigate the algal biodiversity in other to access its suitability for human consumption using known algal indicators of water quality and add to the pool of data useful for long term trends in floral composition in ...

  2. Ankistrodesmus gracilis (Chlorophyta fertilized in swine manure in the laboratory

    Directory of Open Access Journals (Sweden)

    Lúcia Helena Sipaúba-Tavares

    2008-03-01

    Full Text Available The objective of the present work was to investigate the influence of swine manure media on the growth, total length, dry weight, and nutritional value of Ankistrodesmus gracilis microalgae. Two media were measured: “in natura” and biodigested. The growth rate peak for A. gracilis was highest with biodigester treatment (6.2 x 107 cells.mL-1 on the 5th day, at a volume of 2L. The highest percentage of lipids was verifi ed for “in natura” media. Protein was highest (p > 0.05 for the biodigested media at 2L. Biovolume, ash rate, and total length were different (p 0.05. Light demand was also different between media, with lesser intensity being required for biodigested media (13.5μE.cm-2.s-1. In fact, the biodigested media proved to be cheaper in terms of cost and benefit. Generally, the medium containing swine manure, both “in natura” and biodigested, showed better results in A. gracilis development, with water quality adequate for culture systems. Swine manure in both forms may also be used in high-density cultures in the laboratory.

  3. The species in primatology.

    Science.gov (United States)

    Groves, Colin

    2014-01-01

    Biologists of the late eighteenth and early nineteenth centuries all bandied about the term "species," but very rarely actually said what they meant by it. Often, however, one can get inside their thinking by piecing together some of their remarks. One of the most nearly explicit-appropriately, for the man who wrote a book called The Origin of Species - was Charles Darwin: "Practically, when a naturalist can unite two forms together by others having intermediate characters, he treats the one as a variety of the other… He later translated this into evolutionary terms: "Hereafter, we shall be compelled to acknowledge that the only distinction between species and well-marked varieties is, that the latter are known, or believed, to be connected at the present day by intermediate gradations, whereas species were formerly thus connected"(1:484-5.) Copyright © 2014 Wiley Periodicals, Inc.

  4. Hierarchical species distribution models

    Science.gov (United States)

    Hefley, Trevor J.; Hooten, Mevin B.

    2016-01-01

    Determining the distribution pattern of a species is important to increase scientific knowledge, inform management decisions, and conserve biodiversity. To infer spatial and temporal patterns, species distribution models have been developed for use with many sampling designs and types of data. Recently, it has been shown that count, presence-absence, and presence-only data can be conceptualized as arising from a point process distribution. Therefore, it is important to understand properties of the point process distribution. We examine how the hierarchical species distribution modeling framework has been used to incorporate a wide array of regression and theory-based components while accounting for the data collection process and making use of auxiliary information. The hierarchical modeling framework allows us to demonstrate how several commonly used species distribution models can be derived from the point process distribution, highlight areas of potential overlap between different models, and suggest areas where further research is needed.

  5. Endangered Species: Pesticide Restrictions

    Science.gov (United States)

    Our goal is to protect threatened and endangered species and their habitats, without placing unnecessary burden on agriculture and pesticide users. Pesticide limitations are developed to ensure safe use of pesticides in order to meet this goal.

  6. Threatened & Endangered Species Occurrences

    Data.gov (United States)

    Kansas Data Access and Support Center — The database consists of a single statewide coverage of location records for 54 species contained in the Kansas Natural Heritage Inventory database of the Kansas...

  7. Wood Species Recognition System

    OpenAIRE

    Bremananth R; Nithya B; Saipriya R

    2009-01-01

    The proposed system identifies the species of the wood using the textural features present in its barks. Each species of a wood has its own unique patterns in its bark, which enabled the proposed system to identify it accurately. Automatic wood recognition system has not yet been well established mainly due to lack of research in this area and the difficulty in obtaining the wood database. In our work, a wood recognition system has been designed based on pre-processing te...

  8. Sub specie aeternitatis

    Directory of Open Access Journals (Sweden)

    Laura Gioeni

    2012-10-01

    Full Text Available Per delineare il rapporto tra etica ed estetica nell'architettura e rispondere alla domanda principale «che cosa è o dovrebbe essere un buon architetto?», il saggio discute la tesi di Wittgenstein secondo cui «l'opera d'arte è l'oggetto visto sub specie aeternitatis e la vita buona è il mondo visto sub specie aeternitatis. Questa è la connessione tra arte ed etica».

  9. Evaluation of Algae from the effluent of Dandot cement company ...

    African Journals Online (AJOL)

    Twenty genera and fifty species of algae have been reported from the effluent water of Dandot Cement Company. They include thirteen genera and thirty five species from Chlorophyceae; three genera and six species from Cyanophyceae and four genera and nine species from Bacillariophyceae. Camera Lucida drawings ...

  10. Genomic definition of species

    Energy Technology Data Exchange (ETDEWEB)

    Crkvenjakov, R.; Drmanac, R.

    1991-07-01

    The subject of this paper is the definition of species based on the assumption that genome is the fundamental level for the origin and maintenance of biological diversity. For this view to be logically consistent it is necessary to assume the existence and operation of the new law which we call genome law. For this reason the genome law is included in the explanation of species phenomenon presented here even if its precise formulation and elaboration are left for the future. The intellectual underpinnings of this definition can be traced to Goldschmidt. We wish to explore some philosophical aspects of the definition of species in terms of the genome. The point of proposing the definition on these grounds is that any real advance in evolutionary theory has to be correct in both its philosophy and its science.

  11. Bounding species distribution models

    Directory of Open Access Journals (Sweden)

    Thomas J. STOHLGREN, Catherine S. JARNEVICH, Wayne E. ESAIAS,Jeffrey T. MORISETTE

    2011-10-01

    Full Text Available Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for “clamping” model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART and maximum entropy (Maxent models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5: 642–647, 2011].

  12. Bounding Species Distribution Models

    Science.gov (United States)

    Stohlgren, Thomas J.; Jarnevich, Cahterine S.; Morisette, Jeffrey T.; Esaias, Wayne E.

    2011-01-01

    Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS) might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for "clamping" model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART) and maximum entropy (Maxent) models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5): 642-647, 2011].

  13. Prices and species diversity

    DEFF Research Database (Denmark)

    Sauer, Johannes

    . Based on a biologically defined species diver-sity index we incorporate biodiversity either as a desirable output or biodiversity loss as a detrimental input. Beside quantitative shadow price measures the main contribu-tion of the work is the evidence that parametric scores of environmental efficiency...... of biodiversity and the appropriate incorporation in stochastic fron-tier models to achieve more realistic measures of production efficiency. We use the empirical example of tobacco production drawing from as well as affecting species diversity in the surrounding forests. We apply a shadow profit distance...

  14. Seasonal variations in the biochemical composition of some common seaweed species from the coast of Abu Qir Bay, Alexandria, Egypt

    OpenAIRE

    Khairy, Hanan M.; El-Shafay, Shimaa M.

    2013-01-01

    Variations in protein, carbohydrate, lipid, ash, moisture, fatty acid and aminoacid contents of the seaweeds Ulva lactuca Linnaeus (Chlorophyta),Jania rubens (Linnaeus) J.V. Lamouroux and Pterocladia capillacea (S.G. Gmelin) Bornet(Rhodophyta) were studied seasonally from spring to autumn 2010. The seaweeds were collected from a rocky site near Boughaz El-Maadya on the coast of Abu Qir Bay east of Alexandria, Egypt. Remarkable seasonal variations were recorded in the levels of the studied pa...

  15. Translating Dyslexia across Species

    Science.gov (United States)

    Gabel, Lisa A.; Manglani, Monica; Escalona, Nicholas; Cysner, Jessica; Hamilton, Rachel; Pfaffmann, Jeffrey; Johnson, Evelyn

    2016-01-01

    Direct relationships between induced mutation in the "DCDC2" candidate dyslexia susceptibility gene in mice and changes in behavioral measures of visual spatial learning have been reported. We were interested in determining whether performance on a visual-spatial learning and memory task could be translated across species (study 1) and…

  16. on candida species

    African Journals Online (AJOL)

    Abstract. Background: Candida species (sp) is implicated in causing opportunistic disseminated mycotic complications in stage II. HIV patients. Cleistopholis patens is a West African medicinal tree reported to have significant antifungal activity against C. albicans. Objectives: This study aimed to determine the anti-candidal ...

  17. Species Distribution Modelling

    DEFF Research Database (Denmark)

    Gomes, Vitor H. F.; Ijff, Stephanie D.; Raes, Niels

    2018-01-01

    Species distribution models (SDMs) are widely used in ecology and conservation. Presence-only SDMs such as MaxEnt frequently use natural history collections (NHCs) as occurrence data, given their huge numbers and accessibility. NHCs are often spatially biased which may generate inaccuracies in SD...

  18. Chapter 16: Species Diversity

    African Journals Online (AJOL)

    zargaran

    2012-05-03

    May 3, 2012 ... 2008; Zargaran et al., 2008), the oak cynipid gall wasps diversity is yet to be studied. Nazemi et al. (2008) reported species richness of oak gall wasps from. Kurdistan, Ilam and Kermanshah provinces of Iran. Reducing the oak gall wasps diversity will be as an alarm for environmental health of oak forests.

  19. Man as a Species.

    Science.gov (United States)

    Solem, Alan; And Others

    Written in 1964, the document represents experimental material of the Anthropology Curriculum Study Project. The objectives of the project were to discuss the evolution of man as distinguished from the evolution of other species and as related to culture, and to emphasize human diversity. Three brief essays are presented. The first, "The…

  20. Reactive Oxygen Species

    DEFF Research Database (Denmark)

    Franchina, Davide G.; Dostert, Catherine; Brenner, Dirk

    2018-01-01

    oxygen species (ROS), which have long been known to trigger cell death. However, there is now evidence that ROS also act as intracellular signaling molecules both in steady-state and upon antigen recognition. The levels and localization of ROS contribute to the redox modeling of effector proteins...

  1. Ecology of intertidal benthic algae of Northern Karnataka coast

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A.G.; Reddy, C.R.K.; Deshmukhe, G.V.

    The intertidal benthic marine algal flora has been studied for distribution, phenology, biomass and zonation along with the environmental conditions. About 65 species belonging to 42 genera of Chlorophyta, Phaeophyta have been recorded. Rhodophyta...

  2. Additions to the marine algal flora of Curaçao, Netherlands Antilles

    NARCIS (Netherlands)

    Stegenga, H.; Vroman, M.

    1988-01-01

    Nine species of benthic marine algae are reported from the Caribbean island of Curaçao for the first time: Chlorophyta: Derbesia marina and Trichosolen longipedicellata; Phaeophyta: Ectocarpus rhodochortonoides, Feldmannia elachistaeformis, Hecatonema floridanum, Herponema tortugense and Sphacelaria

  3. Productivity and biochemical composition of Tetradesmus obliquus and Phaeodactylum tricornutum

    NARCIS (Netherlands)

    Buono, Silvia; Colucci, Antonella; Angelini, Antonella; Langellotti, Antonio Luca; Massa, Marina; Martello, Anna; Fogliano, Vincenzo; Dibenedetto, Angela

    2016-01-01

    The present work evaluated biomass productivity, carbon dioxide fixation rate, and biochemical composition of two microalgal species, Phaeodactylum tricornutum (Bacillariophyta) and Tetradesmus obliquus (Chlorophyta), cultivated indoors in high-technology photobioreactors (HT-PBR) and outdoors

  4. Occurrence of green alga Ernodesmisverticillata (Kuetzing) Boergesen at Malvan (Maharashtra coast)

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A.G.; Agadi, V.V.

    The occurrence of Ernodesmis verticillata belonging to Chlorophyta has been recorded for the first time from Malvan, along the Maharashtra Coast. The general distribution, habit and habitat of this species are given. During the recent survey...

  5. Studies on structure and organization of calcium carbonate deposits in algae

    Digital Repository Service at National Institute of Oceanography (India)

    Kerkar, V.; Untawale, A.G.

    The structure and organization of calcium carbonate deposits is studied in species of Halimeda, Udotea, Neomeris (Chlorophyta) and Padina (Phaeophyta). It was found that in Halimeda aragonite deposition takes place outside the cell wall...

  6. Resistant biomacromolecules in five marine microalgae of the classes Eustigmatophyceae and Chlorophyceae: Geochemical implications

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Gelin, F.; Boogers, I.; Noordeloos, A.A.M.; Riegman, R.; Leeuw, J.W. de

    1997-01-01

    Non-hydrolysable macromolecular constituents (i.e. algaenans) were isolated from two out of seven marine microalgae investigated. Nannochloropsis salina and Nannochloropsis sp. from the class of Eustigmatophyceae produce highly aliphatic algaenans. Flash pyrolysis and chemical degradations with HI

  7. Effect of grazing-associated infochemicals on growth and morphological, development in Scenedesmus acutus (Chlorophyceae)

    NARCIS (Netherlands)

    Lürling, M.

    1998-01-01

    Populations of the phenotypically plastic alga Scenedesmus acutus Meyen were cultured in standard medium or in medium with filtered water from a Daphnia culture to examine the expression of ecomorphs in both water types. A rapid formation of four- and eight-celled coenobia was observed in the

  8. Spectroscopic investigation of ionizing-radiation tolerance of a Chlorophyceae green micro-alga

    Energy Technology Data Exchange (ETDEWEB)

    Farhi, E; Compagnon, E; Marzloff, V; Ollivier, J; Boisson, A M; Natali, F; Russo, D [Institut Laue-Langevin, BP 156, 38042 Grenoble cedex 9 (France); Rivasseau, C; Gromova, M; Bligny, R [CEA, Laboratoire de Physiologie Cellulaire Vegetale, 17 rue des Martyrs, 38054 Grenoble cedex 9 (France); Coute, A [Museum National d' Histoire Naturelle, Laboratoire de Cryptogamie, 2 rue Buffon, 75005 Paris (France)

    2008-03-12

    Micro-organisms living in extreme environments are captivating in the peculiar survival processes they have developed. Deinococcus radiodurans is probably the most famous radio-resistant bacteria. Similarly, a specific ecosystem has grown in a research reactor storage pool, and has selected organisms which may sustain radiative stress. An original green micro-alga which was never studied for its high tolerance to radiations has been isolated. It is the only autotrophic eukaryote that develops in this pool, although contamination possibilities coming from outside are not unusual. Studying what could explain this irradiation tolerance is consequently very interesting. An integrative study of the effects of irradiation on the micro-algae physiology, metabolism, internal dynamics, and genomics was initiated. In the work presented here, micro-algae were stressed with irradiation doses up to 20 kGy (2 Mrad), and studied by means of nuclear magnetic resonance, looking for modifications in the metabolism, and on the IN13 neutron backscattering instrument at the ILL, looking for both dynamics and structural macromolecular changes in the cells.

  9. Some Chlorophyceae from the marine salines of Bonaire (Netherlands West Indies)

    NARCIS (Netherlands)

    Koster, Joséphine Th.

    1943-01-01

    A collection of samples containing algae from the salines of Bonaire was brought home by Mr P. Wagenaar Hummelinck from his trips to the Netherlands West Indian Islands in 1930 and in 1936—1937. Though these trips were chiefly undertaken in order to gather zoological material (1, 2) 1), the

  10. CHANGES IN ENDOGENOUS CYTOKININ CONCENTRATIONS IN CHLORELLA (CHLOROPHYCEAE) IN RELATION TO LIGHT AND THE CELL CYCLE

    Czech Academy of Sciences Publication Activity Database

    Stirk, W. A.; van Staden, J.; Novák, Ondřej; Doležal, Karel; Strnad, Miroslav; Dobrev, Petre; Sipos, G.; Oerdoeg, V.; Balint, P.

    2011-01-01

    Roč. 47, č. 2 (2011), s. 291-301 ISSN 0022-3646 R&D Projects: GA ČR GA301/08/1649; GA ČR GA206/09/1284 Institutional research plan: CEZ:AV0Z50380511 Keywords : cell cycle * Chlorella * cis-zeatin * cytokinins * N6-(2-isopentenyl)adenine Subject RIV: EF - Botanics Impact factor: 2.071, year: 2011

  11. Positive feedback in species communities

    NARCIS (Netherlands)

    Gerla, D.J.

    2012-01-01

    Sometimes the eventual population densities in a species community depend on the initial densities or the arrival times of species. If arrival times determine species composition, a priority effect has occurred. Priority effects may occur if the species community exhibits alternative stable states

  12. Prior indigenous technological species

    Science.gov (United States)

    Wright, Jason T.

    2018-01-01

    One of the primary open questions of astrobiology is whether there is extant or extinct life elsewhere the solar system. Implicit in much of this work is that we are looking for microbial or, at best, unintelligent life, even though technological artefacts might be much easier to find. Search for Extraterrestrial Intelligence (SETI) work on searches for alien artefacts in the solar system typically presumes that such artefacts would be of extrasolar origin, even though life is known to have existed in the solar system, on Earth, for eons. But if a prior technological, perhaps spacefaring, species ever arose in the solar system, it might have produced artefacts or other technosignatures that have survived to present day, meaning solar system artefact SETI provides a potential path to resolving astrobiology's question. Here, I discuss the origins and possible locations for technosignatures of such a prior indigenous technological species, which might have arisen on ancient Earth or another body, such as a pre-greenhouse Venus or a wet Mars. In the case of Venus, the arrival of its global greenhouse and potential resurfacing might have erased all evidence of its existence on the Venusian surface. In the case of Earth, erosion and, ultimately, plate tectonics may have erased most such evidence if the species lived Gyr ago. Remaining indigenous technosignatures might be expected to be extremely old, limiting the places they might still be found to beneath the surfaces of Mars and the Moon, or in the outer solar system.

  13. Estimating Effects of Species Interactions on Populations of Endangered Species.

    Science.gov (United States)

    Roth, Tobias; Bühler, Christoph; Amrhein, Valentin

    2016-04-01

    Global change causes community composition to change considerably through time, with ever-new combinations of interacting species. To study the consequences of newly established species interactions, one available source of data could be observational surveys from biodiversity monitoring. However, approaches using observational data would need to account for niche differences between species and for imperfect detection of individuals. To estimate population sizes of interacting species, we extended N-mixture models that were developed to estimate true population sizes in single species. Simulations revealed that our model is able to disentangle direct effects of dominant on subordinate species from indirect effects of dominant species on detection probability of subordinate species. For illustration, we applied our model to data from a Swiss amphibian monitoring program and showed that sizes of expanding water frog populations were negatively related to population sizes of endangered yellow-bellied toads and common midwife toads and partly of natterjack toads. Unlike other studies that analyzed presence and absence of species, our model suggests that the spread of water frogs in Central Europe is one of the reasons for the decline of endangered toad species. Thus, studying population impacts of dominant species on population sizes of endangered species using data from biodiversity monitoring programs should help to inform conservation policy and to decide whether competing species should be subject to population management.

  14. The functional biogeography of species

    DEFF Research Database (Denmark)

    Carstensen, Daniel W.; Dalsgaard, Bo; Svenning, Jens-Christian

    2013-01-01

    Biogeographical systems can be analyzed as networks of species and geographical units. Within such a biogeographical network, individual species may differ fundamentally in their linkage pattern, and therefore hold different topological roles. To advance our understanding of the relationship...... between species traits and large-scale species distribution patterns in archipelagos, we use a network approach to classify birds as one of four biogeographical species roles: peripherals, connectors, module hubs, and network hubs. These roles are based upon the position of species within the modular...... network of islands and species in Wallacea and the West Indies. We test whether species traits - including habitat requirements, altitudinal range-span, feeding guild, trophic level, and body length - correlate with species roles. In both archipelagos, habitat requirements, altitudinal range-span and body...

  15. Penicillium species causing onychomycosis.

    Directory of Open Access Journals (Sweden)

    Ramani R

    1994-04-01

    Full Text Available Onychomycosis caused by mould infection is rare. A 40 year old male patient presented with dystrophic finger nails and multiple, erythematous lesions with slightly raised borders and scaling all over the body. The patient was a known diabetic. He did not respond to griseofulvin. Samples from nails and skin scales were cultured. From the nails, Penicillium species and from the skin scales. Trichophyton rubrum were isolated. Ketoconazole therapy (200 mg twice daily x 4 mths led to complete cure with negative cultures and normalization of nails.

  16. Species concepts, species delimitation and the inherent limitations ...

    Indian Academy of Sciences (India)

    Frank Zachos

    genes” (ibid., italics in the original). Hill focuses on birds, but in principle the concept could be applicable more widely. It is similar to the Genetic and the Differential Fitness Species ..... into account social and financial ramifications of species status (as when the habitat of an endangered species needs protection) not only ...

  17. Species concepts, species delimitation and the inherent limitations ...

    Indian Academy of Sciences (India)

    Frank Zachos

    The nuisance of having to deal with so many species concepts can be reinterpreted as a situation in which various lines ... understanding of the species category and its ontology, but the most pressing practical problem remains ..... into account social and financial ramifications of species status (as when the habitat of an.

  18. Save Our Species: Protecting Endangered Species from Pesticides.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC.

    This full-size poster profiles 11 wildlife species that are endangered. Color illustrations of animals and plants are accompanied by narrative describing their habitats and reasons for endangerment. The reverse side of the poster contains information on the Endangered Species Act, why protecting endangered and threatened species is important, how…

  19. Identification of malassezia species

    Directory of Open Access Journals (Sweden)

    Kindo A

    2004-01-01

    Full Text Available Malassezia spp. are lipophilic unipolar yeasts recognized as commensals of skin that may be pathogenic under certain conditions. The genus Malassezia now comprises of seven species. This study was aimed at using a simple practical approach to speciate Malassezia yeasts from clinical material. Seventy skin scrapings from patients with pityriasis versicolor infection, positive in 10% potassium hydroxide (KOH, were cultured onto modified Dixon′s agar (mDixon′s agar and Sabouraud dextrose agar (SDA and incubated at 32ºC. Speciation was done on the basis of Gram stain morphology, catalase test, and utilization of Tweens. Out of 70 scrapings 48 (68.75% showed growth on mDixon′s agar. The commonest isolate was M. sympodialis (28, 58% followed by M. globosa (19, 40% and one isolate was (2% of M. restricta. M. sympodialis was the commonest species affecting our population and there was no isolation of M. obtusa, M. slooffiae, M. pachydermatis and M. furfur.

  20. Endangered Species Act Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

  1. New species of Malaysian ferns

    NARCIS (Netherlands)

    Holttum, R.E.

    1962-01-01

    The present paper includes descriptions of several new species of ferns found among recent collections from various parts of Malaysia; also two new combinations of names of species which are of interest on account of their taxonomic history.

  2. New Malesian species of Viscaceae

    NARCIS (Netherlands)

    Barlow, Bryan A.

    1996-01-01

    Three new Malesian species of Viscaceae are described. Ginalloa flagellaris Barlow is distinguished as a species from New Guinea and New Britain, previously included within G. arnottiana Korthals. Viscum exile Barlow is recognized as a new species endemic to Celebes, related to V. ovalifolium.

  3. 75 FR 78974 - Endangered Species

    Science.gov (United States)

    2010-12-17

    ...-XA086 Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... the Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.) and the regulations governing the taking, importing, and exporting of endangered and threatened species (50 CFR 222-226). Permit...

  4. California Endangered Species Resource Guide.

    Science.gov (United States)

    California State Dept. of Education, Los Angeles.

    This document was developed in response to California Senate Bill No. 885, "The Endangered Species Education Project," that called for a statewide program in which schools adopt a local endangered species, research past and current efforts to preserve the species' habitat, develop and implement an action plan to educate the community…

  5. 76 FR 2348 - Endangered Species

    Science.gov (United States)

    2011-01-13

    .... 15596] Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... requested permit has been issued under the authority of the Endangered Species Act of 1973, as amended (ESA... endangered and threatened species (50 CFR parts 222-226). The North Carolina Aquarium at Fort Fisher has been...

  6. Electrosmog and species conservation

    International Nuclear Information System (INIS)

    Balmori, Alfonso

    2014-01-01

    Despite the widespread use of wireless telephone networks around the world, authorities and researchers have paid little attention to the potential harmful effects of mobile phone radiation on wildlife. This paper briefly reviews the available scientific information on this topic and recommends further studies and specific lines of research to confirm or refute the experimental results to date. Controls must be introduced and technology rendered safe for the environment, particularly, threatened species. - Highlights: • Studies have shown effects in both animals and plants. • Two thirds of the studies reported ecological effects. • There is little research in this area and further research is needed. • The technology must be safe. • Controls should be introduced to mitigate the possible effects

  7. Checklist of Phytoplankton of Shendam Reserviour in Plateau State ...

    African Journals Online (AJOL)

    A qualitative study of phytoplankton flora was carried out in Shendam reservoir, Plateau state of Nigeria. Seventy one species were recorded indicating a fairly low species number when compared to other Nigerian waters. The major groups of phytoplankton found were chlorophyceae, bacilliarophyceae, cyanophyceae and ...

  8. Native species that can replace exotic species in landscaping

    Directory of Open Access Journals (Sweden)

    Elisabeth Regina Tempel Stumpf

    2015-08-01

    Full Text Available Beyond aesthetics, the contemporary landscaping intends to provide other benefits for humans and environment, especially related to the environmental quality of urban spaces and conservation of the species. A trend in this direction is the reduction in the use of exotic plants in their designs, since, over time, they can become agents of replacement of native flora, as it has occurred in Rio Grande do Sul with many species introduced by settlers. However, the use of exotic species is unjustifiable, because the flora diversity of the Bioma Pampa offers many native species with appropriate features to the ornamental use. The commercial cultivation and the implantation of native species in landscaped areas constitute innovations for plant nurseries and landscapers and can provide a positive reduction in extractivism, contributing to dissemination, exploitation and preservation of native flora, and also decrease the impact of chemical products on environment. So, this work intends to identify native species of Bioma Pampa with features and uses similar to the most used exotic species at Brazilian landscaping. The species were selected from consulting books about native plants of Bioma Pampa and plants used at Brazilian landscaping, considering the similarity on habit and architecture, as well as characteristics of leafs, flowers and/or fruits and environmental conditions of occurrence and cultivation. There were identified 34 native species able to properly replace exotic species commonly used. The results show that many native species of Bioma Pampa have interesting ornamental features to landscape gardening, allowing them to replace exotic species that are traditionally cultivated.

  9. Species of Wadicosa (Araneae, Lycosidae): a new species from Madagascar.

    Science.gov (United States)

    Kronestedt, Torbjörn

    2017-05-10

    Since establishing the wolf spider genus Wadicosa Zyuzin, 1985 (Zyuzin 1985), eleven species have been accepted in it, either by transfer from Lycosa Latreille, 1804 or Pardosa C.L. Koch, 1847 or by original designation (WSC 2017). However, according to Kronestedt (1987), additional species wait to be formally transferred to Wadicosa. The genus is restricted to the Old World, with one species, Wadicosa jocquei Kronestedt, 2015, recently described from Madagascar and surrounding islands.

  10. Ring species as demonstrations of the continuum of species formation

    DEFF Research Database (Denmark)

    Pereira, Ricardo José Do Nascimento; Wake, David B.

    2015-01-01

    In the mid-20th century, Ernst Mayr (1942) and Theodosius Dobzhansky (1958) championed the significance of 'circular overlaps' or 'ring species' as the perfect demonstration of the gradual nature of species formation. As an ancestral species expands its range, wrapping around a geographic barrier...... in this issue of Molecular Ecology by Fuchs et al. (2015), focused on the entire genealogy of a bulbul (Alophoixus) species complex, offers key insights into the evolutionary processes underlying diversification of this Indo-Malayan bird. Their findings fulfil most of the criteria that can be expected for ring...

  11. Population genetics and cryptic species

    International Nuclear Information System (INIS)

    McPheron, Bruce A.

    2000-01-01

    Does the definition of a species matter for pest management purposes? Taxonomists provide us with tools - usually morphological characters - to identify a group of organisms that we call a species. The implication of this identification is that all of the individuals that fit the provided description are members of the species in question. The taxonomists have considered the range of variation among individuals in defining the species, but this variation is often forgotten when we take the concept of species to the level of management. Just as there is morphological variation among individuals, there is also variation in practically any character we might imagine, which has implications for the short and long term success of our management tactics. The rich literature on insecticide resistance should be a constant reminder of the fact that the pressure on pest survival and reproduction applied by our management approaches frequently leads to evolutionary changes within the pest species. The degree of variation within a particular species is a defining characteristic of that species. This level of variability may have very important implications for successful management, so it is very important to measure variation and, whenever possible, the genetic basis of that variation, in a target species. Population genetic approaches can provide evidence of genetic structure (or lack thereof) among populations of a species. These types of data can be used to discuss the movement of pest populations on a local or global scale. In other cases, we may have a complex of species that share some, but not all, characteristics. Species complexes that share morphological characters (i.e., cannot be easily distinguished) but not biological characters are referred to as sibling or cryptic species

  12. Armillaria species in coniferous stands

    Directory of Open Access Journals (Sweden)

    Anna Żółciak

    2013-12-01

    Full Text Available Identification of the Armillaria species in selected coniferous stands (Scots pine stands, Norway spruce stands and fir stands was the aim of the work carried out on the basis of mating tests and consideration of macroscopic traits of fruit-bodies. One species of Armillaria [A. ostoyae (Romagnesi Herink] was found in Scots pine stands, three species [A. ostoyae, A. cepistipes Velenovský and A. borealis Marxmüller et Korhonen] were found in Norway spruce stands and two species [A. ostoyae and A. cepistipes] were found in fir stands.

  13. Uncommon Species and Other Features

    Data.gov (United States)

    Vermont Center for Geographic Information — The Vermont Fish and Wildlife Department's Natural Heritage Inventory (NHI) maintains a database of uncommon, rare, threatened and endangered species and natural...

  14. Balance of bacterial species in the gut

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Balance of bacterial species in the gut. Protective. Lactobacillus species. Bifidobacterium species. Selected E. coli. Saccharomyces boulardii. Clostridium butyricum.

  15. Removing other Tree Species does not benefit the Timber Species ...

    African Journals Online (AJOL)

    The endemic canopy tree Cephalosphaera usambarensis is a valuable timber species in montane rainforest of Tanzania. Here we evaluate an experiment in which mature trees of species other than C. usambarensis were removed from an area in the East Usambara Mountains. We compared stage/size structure of the ...

  16. Fuzzy species among recombinogenic bacteria

    Directory of Open Access Journals (Sweden)

    Fraser Christophe

    2005-03-01

    Full Text Available Abstract Background It is a matter of ongoing debate whether a universal species concept is possible for bacteria. Indeed, it is not clear whether closely related isolates of bacteria typically form discrete genotypic clusters that can be assigned as species. The most challenging test of whether species can be clearly delineated is provided by analysis of large populations of closely-related, highly recombinogenic, bacteria that colonise the same body site. We have used concatenated sequences of seven house-keeping loci from 770 strains of 11 named Neisseria species, and phylogenetic trees, to investigate whether genotypic clusters can be resolved among these recombinogenic bacteria and, if so, the extent to which they correspond to named species. Results Alleles at individual loci were widely distributed among the named species but this distorting effect of recombination was largely buffered by using concatenated sequences, which resolved clusters corresponding to the three species most numerous in the sample, N. meningitidis, N. lactamica and N. gonorrhoeae. A few isolates arose from the branch that separated N. meningitidis from N. lactamica leading us to describe these species as 'fuzzy'. Conclusion A multilocus approach using large samples of closely related isolates delineates species even in the highly recombinogenic human Neisseria where individual loci are inadequate for the task. This approach should be applied by taxonomists to large samples of other groups of closely-related bacteria, and especially to those where species delineation has historically been difficult, to determine whether genotypic clusters can be delineated, and to guide the definition of species.

  17. 50 CFR Table 2c to Part 679 - Species Codes: FMP Forage Fish Species (all species of the following families)

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Species Codes: FMP Forage Fish Species (all species of the following families) 2c Table 2c to Part 679 Wildlife and Fisheries FISHERY...: FMP Forage Fish Species (all species of the following families) Species Description Code Bristlemouths...

  18. Insular species swarm goes underground

    DEFF Research Database (Denmark)

    P. S. Reboleira, Ana Sofia; Enghoff, Henrik

    2014-01-01

    -group, an insular species swarm distributed in the archipelagos of Madeira and the Canary Islands. We discuss the differences between the new species and their relatives and present information on the subterranean environment of Madeira. An updated overview of the subterranean biodiversity of millipedes...

  19. 76 FR 74778 - Endangered Species

    Science.gov (United States)

    2011-12-01

    .... 16439] Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... has been issued under the authority of the Endangered Species Act of 1973, as amended (ESA; 16 U.S.C. 1531 et seq.) and the regulations governing the taking, importing, and exporting of endangered and...

  20. 76 FR 1405 - Endangered Species

    Science.gov (United States)

    2011-01-10

    ...-XA128 Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and..., importing, and exporting of endangered and threatened species (50 CFR parts 222-226). The five-year permit... above- named organization. The requested permit has been issued under the authority of the Endangered...

  1. Species delimitation and global biosecurity.

    Science.gov (United States)

    Boykin, Laura M; Armstrong, Karen F; Kubatko, Laura; De Barro, Paul

    2012-01-01

    Species delimitation directly impacts on global biosecurity. It is a critical element in the decisions made by national governments in regard to the flow of trade and to the biosecurity measures imposed to protect countries from the threat of invasive species. Here we outline a novel approach to species delimitation, "tip to root", for two highly invasive insect pests, Bemisia tabaci (sweetpotato whitefly) and Lymantria dispar (Asian gypsy moth). Both species are of concern to biosecurity, but illustrate the extremes of phylogenetic resolution that present the most complex delimitation issues for biosecurity; B. tabaci having extremely high intra-specific genetic variability and L. dispar composed of relatively indistinct subspecies. This study tests a series of analytical options to determine their applicability as tools to provide more rigorous species delimitation measures and consequently more defensible species assignments and identification of unknowns for biosecurity. Data from established DNA barcode datasets (COI), which are becoming increasingly considered for adoption in biosecurity, were used here as an example. The analytical approaches included the commonly used Kimura two-parameter (K2P) inter-species distance plus four more stringent measures of taxon distinctiveness, (1) Rosenberg's reciprocal monophyly, (P(AB)),1 (2) Rodrigo's (P(randomly distinct)),2 (3) genealogical sorting index, (gsi),3 and (4) General mixed Yule-coalescent (GMYC).4,5 For both insect datasets, a comparative analysis of the methods revealed that the K2P distance method does not capture the same level of species distinctiveness revealed by the other three measures; in B. tabaci there are more distinct groups than previously identified using the K2P distances and for L. dipsar far less variation is apparent within the predefined subspecies. A consensus for the results from P(AB), P(randomly distinct) and gsi offers greater statistical confidence as to where genetic limits might

  2. Species recognition and cryptic species in the Tuber indicum complex.

    Directory of Open Access Journals (Sweden)

    Juan Chen

    Full Text Available Morphological delimitation of Asian black truffles, including Tuber himalayense, T. indicum, T. sinense, T. pseudohimalayense, T. formosanum and T. pseudoexcavatum, has remained problematic and even phylogenetic analyses have been controversial. In this study, we combined five years of field investigation in China with morphological study and DNA sequences analyses (ITS, LSU and β-tubulin of 131 Tuber specimens to show that T. pseudohimalayense and T. pseudoexcavatum are the same species. T. formosanum is a separate species based on its host plants and geographic distribution, combined with minor morphological difference from T. indicum. T. sinense should be treated as a synonym of T. indicum. Our results demonstrate that the present T. indicum, a single described morphological species, should include at least two separate phylogenetic species. These findings are of high importance for truffle taxonomy and reveal and preserve the richness of truffle diversity.

  3. Genome Sequences of Oryza Species

    KAUST Repository

    Kumagai, Masahiko

    2018-02-14

    This chapter summarizes recent data obtained from genome sequencing, annotation projects, and studies on the genome diversity of Oryza sativa and related Oryza species. O. sativa, commonly known as Asian rice, is the first monocot species whose complete genome sequence was deciphered based on physical mapping by an international collaborative effort. This genome, along with its accurate and comprehensive annotation, has become an indispensable foundation for crop genomics and breeding. With the development of innovative sequencing technologies, genomic studies of O. sativa have dramatically increased; in particular, a large number of cultivars and wild accessions have been sequenced and compared with the reference rice genome. Since de novo genome sequencing has become cost-effective, the genome of African cultivated rice, O. glaberrima, has also been determined. Comparative genomic studies have highlighted the independent domestication processes of different rice species, but it also turned out that Asian and African rice share a common gene set that has experienced similar artificial selection. An international project aimed at constructing reference genomes and examining the genome diversity of wild Oryza species is currently underway, and the genomes of some species are publicly available. This project provides a platform for investigations such as the evolution, development, polyploidization, and improvement of crops. Studies on the genomic diversity of Oryza species, including wild species, should provide new insights to solve the problem of growing food demands in the face of rapid climatic changes.

  4. Molecular Typing of Nocardia Species

    Directory of Open Access Journals (Sweden)

    Seyyed Saeed Eshraghi

    2012-03-01

    Full Text Available Identification of clinically significant Nocardia species is essential for the definitive diagnosis, predict antimicrobial susceptibility, epidemiological purposes, and for an effective treatment. Conventional identification of Nocardia species in routine medical laboratories which is based on phenotypic (cellular morphology, colonial characteristics, biochemical and enzymatic profiles, and chemotaxonomic characteristics is often laborious, and time-consuming. The procedure requires expertise, and newer species can be difficult to differentiate with accuracy from other related species. Alternative methods of identification, such as high performance liquid chromatography (HPLC and molecular biology techniques allow a better characterization of species. The taxonomy of the genus Nocardia has been dramatically been revised during the last decade and more than 30 valid human clinical significance species of Nocardia have been reported. The use of molecular approaches, including 16S rRNA gene sequencing, restriction fragment length polymorphism (RFLP or PCR restriction endonuclease analysis has been the focus of recent investigations to distinguish the isolates of Nocardia from other actinomycetes genera. The methods have revolutionized the characterization of the Nocardiae by providing rapid, sensitive, and accurate identification procedures. The present review describes the currently known medically important pathogenic species of Nocardia.

  5. Species-area relationships are controlled by species traits.

    Science.gov (United States)

    Franzén, Markus; Schweiger, Oliver; Betzholtz, Per-Eric

    2012-01-01

    The species-area relationship (SAR) is one of the most thoroughly investigated empirical relationships in ecology. Two theories have been proposed to explain SARs: classical island biogeography theory and niche theory. Classical island biogeography theory considers the processes of persistence, extinction, and colonization, whereas niche theory focuses on species requirements, such as habitat and resource use. Recent studies have called for the unification of these two theories to better explain the underlying mechanisms that generates SARs. In this context, species traits that can be related to each theory seem promising. Here we analyzed the SARs of butterfly and moth assemblages on islands differing in size and isolation. We tested whether species traits modify the SAR and the response to isolation. In addition to the expected overall effects on the area, traits related to each of the two theories increased the model fit, from 69% up to 90%. Steeper slopes have been shown to have a particularly higher sensitivity to area, which was indicated by species with restricted range (slope = 0.82), narrow dietary niche (slope= 0.59), low abundance (slope= 0.52), and low reproductive potential (slope = 0.51). We concluded that considering species traits by analyzing SARs yields considerable potential for unifying island biogeography theory and niche theory, and that the systematic and predictable effects observed when considering traits can help to guide conservation and management actions.

  6. Occurrence and Deleterious Effects of Algal Blooms Associated With ...

    African Journals Online (AJOL)

    Bloom-forming algal families found in association included members of the phytoplankton class Chlorophyceae: (Pediastrium spp and Spirogyra spp.), the Bacillariophyceae which included Synedra, Melosira and Nitzschia species and potentially toxin-producing genera of the class Cyanophyceae (Microcystis, Anabaena, ...

  7. Evolution of mutualism between species

    Energy Technology Data Exchange (ETDEWEB)

    Post, W.M.; Travis, C.C.; DeAngelis, D.L.

    1980-01-01

    Recent theoretical work on mutualism, the interaction between species populations that is mutually beneficial, is reviewed. Several ecological facts that should be addressed in the construction of dynamic models for mutualism are examined. Basic terminology is clarified. (PSB)

  8. The Candida Pathogenic Species Complex

    Science.gov (United States)

    Turner, Siobhán A.; Butler, Geraldine

    2014-01-01

    Candida species are the most common causes of fungal infection. Approximately 90% of infections are caused by five species: Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei. Three (C. albicans, C. tropicalis, and C. parapsilosis) belong to the CTG clade, in which the CTG codon is translated as serine and not leucine. C. albicans remains the most commonly isolated but is decreasing relative to the other species. The increasing incidence of C. glabrata is related to its reduced susceptibility to azole drugs. Genome analysis suggests that virulence in the CTG clade is associated with expansion of gene families, particularly of cell wall genes. Similar independent processes took place in the C. glabrata species group. Gene loss and expansion in an ancestor of C. glabrata may have resulted in preadaptations that enabled pathogenicity. PMID:25183855

  9. Achromobacter species in cystic fibrosis

    DEFF Research Database (Denmark)

    Hansen, C R; Pressler, T; Ridderberg, W

    2013-01-01

    Achromobacter species leads to chronic infection in an increasing number of CF patients. We report 2 cases of Achromobacter ruhlandii cross-infection between patients after well-described indirect contact....

  10. Infrared spectra of mineral species

    CERN Document Server

    Chukanov, Nikita V

    2014-01-01

    This book details more than 3,000 IR spectra of more than 2,000 mineral species collected during last 30 years. It features full descriptions and analytical data of each sample for which IR spectrum was obtained.

  11. Earth Day: All Species Projects.

    Science.gov (United States)

    Kraft, Marty

    1994-01-01

    Describes the All Species Project, an interdisciplinary program that attempts to build a sense of community and understanding of the natural world by integrating ideas from art, science, anthropology, counseling, theater, and any other area deemed applicable. (MDH)

  12. EAMJ Species April 10.indd

    African Journals Online (AJOL)

    2010-04-04

    albicans Candida species. (17). In the setting of candidemia and deep infections susceptibility testing may be of benefit especially in cases where initial therapy has failed, the results may guide on suitable adjustment of therapy.

  13. Theoretical microbial ecology without species

    Science.gov (United States)

    Tikhonov, Mikhail

    2017-09-01

    Ecosystems are commonly conceptualized as networks of interacting species. However, partitioning natural diversity of organisms into discrete units is notoriously problematic and mounting experimental evidence raises the intriguing question whether this perspective is appropriate for the microbial world. Here an alternative formalism is proposed that does not require postulating the existence of species as fundamental ecological variables and provides a naturally hierarchical description of community dynamics. This formalism allows approaching the species problem from the opposite direction. While the classical models treat a world of imperfectly clustered organism types as a perturbation around well-clustered species, the presented approach allows gradually adding structure to a fully disordered background. The relevance of this theoretical construct for describing highly diverse natural ecosystems is discussed.

  14. Phenotypic Plasticity and Species Coexistence.

    Science.gov (United States)

    Turcotte, Martin M; Levine, Jonathan M

    2016-10-01

    Ecologists are increasingly interested in predicting how intraspecific variation and changing trait values impact species interactions and community composition. For many traits, much of this variation is caused by phenotypic plasticity, and thus the impact of plasticity on species coexistence deserves robust quantification. Partly due to a lack of sound theoretical expectations, empirical studies make contradictory claims regarding plasticity effects on coexistence. Our critical review of this literature, framed in modern coexistence theory, reveals that plasticity affects species interactions in ways that could impact stabilizing niche differences and competitive asymmetries. However, almost no study integrates these measures to quantify the net effect of plasticity on species coexistence. To address this challenge, we outline novel empirical approaches grounded in modern theory. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Species delimitation in the Stenocereus griseus (Cactaceae species complex reveals a new species, S. huastecorum.

    Directory of Open Access Journals (Sweden)

    Hernán Alvarado-Sizzo

    Full Text Available The Stenocereus griseus species complex (SGSC has long been considered taxonomically challenging because the number of taxa belonging to the complex and their geographical boundaries remain poorly understood. Bayesian clustering and genetic distance-based methods were used based on nine microsatellite loci in 377 individuals of three main putative species of the complex. The resulting genetic clusters were assessed for ecological niche divergence and areolar morphology, particularly spination patterns. We based our species boundaries on concordance between genetic, ecological, and morphological data, and were able to resolve four species, three of them corresponding to S. pruinosus from central Mexico, S. laevigatus from southern Mexico, and S. griseus from northern South America. A fourth species, previously considered to be S. griseus and commonly misidentified as S. pruinosus in northern Mexico showed significant genetic, ecological, and morphological differentiation suggesting that it should be considered a new species, S. huastecorum, which we describe here. We show that population genetic analyses, ecological niche modeling, and morphological studies are complementary approaches for delimiting species in taxonomically challenging plant groups such as the SGSC.

  16. Chapter 07: Species description pages

    Science.gov (United States)

    Alex C. Wiedenhoeft

    2011-01-01

    These pages are written to be the final step in the identification process; you will be directed to them by the key in Chapter 6. Each species or group of similar species in the same genus has its own set of pages. The information in the first page describes the characteristics of the wood covered in the manual. The page shows images of similar or confusable woods,...

  17. Species Egalitarianism and the Environment

    Directory of Open Access Journals (Sweden)

    Kristin Tiili

    2014-06-01

    Full Text Available A general anthropocentric view of the human species affects the environment and is a major contributing factor in the environmental crisis we are currently facing. A species egalitarian society would have positive effects on the crisis, and particularly in regards to short term goals of decreasing greenhouse gases in the atmosphere. Additionally it would increase the quality of life and alleviate the suffering of countless beings, nonhuman animals and humans alike.

  18. Seed dormancy in alpine species

    OpenAIRE

    Schwienbacher, Erich; Navarro-Cano, Jose Antonio; Neuner, Gilbert; Erschbamer, Brigitta

    2011-01-01

    In alpine species the classification of the various mechanisms underlying seed dormancy has been rather questionable and controversial. Thus, we investigated 28 alpine species to evaluate the prevailing types of dormancy. Embryo type and water impermeability of seed coats gave an indication of the potential seed dormancy class. To ascertain the actual dormancy class and level, we performed germination experiments comparing the behavior of seeds without storage, after cold-dry storage, after c...

  19. Endangered Lilium Species of Turkey

    Directory of Open Access Journals (Sweden)

    Sevim Demir

    2018-01-01

    Full Text Available Turkey, which is among the major gene centers of the world and has a special place in plant genetic diversity. However, many plant genetic resources, including geophytes, are under genetic erosion because of the environmental and other problems and therefore face with the danger of extinction. Lilium ciliatum is endemic to North East Anatolia. IUCN (International Union for the Conservation of Natural Resources Red List Category of this species is Endangered (EN. Lilium ciliatum naturally grown in Zigana pass, Bayburt, Trabzon, Bulancak, Giresun and Gümüşhane is endangered and major threats of L. ciliatum are road construction and human disturbance related to ecotourism and recreation. It was reported that Lilium carniolicum naturally grown in Turkey is endangered although it isn’t in the IUCN Red List. Distribution areas of L. carniolicum are Trabzon, Rize, Artvin and it is also endemic to North East Anatolia. These species have high potential for use as ornamental plants with their colorful big flowers. In addition, the bulbs of these species are also used in the cosmetic industry and medicine. These are the main properties that increase the importance of L. ciliatum and L. carniolicum species. Therefore it is very important to protect the habitats of these species, ensure the continuity of their generations. The disappearance of these endemic species from our country means to disappear from the world. This review has been given in order to give some information about the endangered Lilium species of Turkey and conservation actions on these species in Turkey flora and take attention to the issue.

  20. Collective behaviour across animal species.

    Science.gov (United States)

    DeLellis, Pietro; Polverino, Giovanni; Ustuner, Gozde; Abaid, Nicole; Macrì, Simone; Bollt, Erik M; Porfiri, Maurizio

    2014-01-16

    We posit a new geometric perspective to define, detect, and classify inherent patterns of collective behaviour across a variety of animal species. We show that machine learning techniques, and specifically the isometric mapping algorithm, allow the identification and interpretation of different types of collective behaviour in five social animal species. These results offer a first glimpse at the transformative potential of machine learning for ethology, similar to its impact on robotics, where it enabled robots to recognize objects and navigate the environment.

  1. Echinacea species of medicinal use

    OpenAIRE

    Leon Sorin MUNTEAN; Dan VARBAN; Sorin MUNTEAN; Mircea TAMAS; Rodica VARBAN

    1998-01-01

    Echinacea species come from North America. Preparations of Echinacea pallida Nutt. and Echinacea purpurea (L.) Moench are used in healing many diseases owing to their immunostimulative, antivirus and bacteria, scarifying and anti-inflammatory properties. Echinacea pallida Nutt. displays tap root, linear spear-shaped leaves. Seedling plantation with both species is performed in May and spacing of 50 cm between rows and 30 cm between plants per row. Harvest takes place in the 2-nd year of flowe...

  2. Keystone species and food webs.

    Science.gov (United States)

    Jordán, Ferenc

    2009-06-27

    Different species are of different importance in maintaining ecosystem functions in natural communities. Quantitative approaches are needed to identify unusually important or influential, 'keystone' species particularly for conservation purposes. Since the importance of some species may largely be the consequence of their rich interaction structure, one possible quantitative approach to identify the most influential species is to study their position in the network of interspecific interactions. In this paper, I discuss the role of network analysis (and centrality indices in particular) in this process and present a new and simple approach to characterizing the interaction structures of each species in a complex network. Understanding the linkage between structure and dynamics is a condition to test the results of topological studies, I briefly overview our current knowledge on this issue. The study of key nodes in networks has become an increasingly general interest in several disciplines: I will discuss some parallels. Finally, I will argue that conservation biology needs to devote more attention to identify and conserve keystone species and relatively less attention to rarity.

  3. The Colletotrichum gloeosporioides species complex.

    Science.gov (United States)

    Weir, B S; Johnston, P R; Damm, U

    2012-09-15

    The limit of the Colletotrichum gloeosporioides species complex is defined genetically, based on a strongly supported clade within the Colletotrichum ITS gene tree. All taxa accepted within this clade are morphologically more or less typical of the broadly defined C. gloeosporioides, as it has been applied in the literature for the past 50 years. We accept 22 species plus one subspecies within the C. gloeosporioides complex. These include C. asianum, C. cordylinicola, C. fructicola, C. gloeosporioides, C. horii, C. kahawae subsp. kahawae, C. musae, C. nupharicola, C. psidii, C. siamense, C. theobromicola, C. tropicale, and C. xanthorrhoeae, along with the taxa described here as new, C. aenigma, C. aeschynomenes, C. alatae, C. alienum, C. aotearoa, C. clidemiae, C. kahawae subsp. ciggaro, C. salsolae, and C. ti, plus the nom. nov. C. queenslandicum (for C. gloeosporioides var. minus). All of the taxa are defined genetically on the basis of multi-gene phylogenies. Brief morphological descriptions are provided for species where no modern description is available. Many of the species are unable to be reliably distinguished using ITS, the official barcoding gene for fungi. Particularly problematic are a set of species genetically close to C. musae and another set of species genetically close to C. kahawae, referred to here as the Musae clade and the Kahawae clade, respectively. Each clade contains several species that are phylogenetically well supported in multi-gene analyses, but within the clades branch lengths are short because of the small number of phylogenetically informative characters, and in a few cases individual gene trees are incongruent. Some single genes or combinations of genes, such as glyceraldehyde-3-phosphate dehydrogenase and glutamine synthetase, can be used to reliably distinguish most taxa and will need to be developed as secondary barcodes for species level identification, which is important because many of these fungi are of biosecurity

  4. Are hybrid species more fit than ancestral parent species in the current hybrid species habitats?

    NARCIS (Netherlands)

    Donovan, L.A.; Rosenthal, D.R.; Sanchez-Velenosi, M.; Rieseberg, L.H.; Ludwig, F.

    2010-01-01

    Hybrid speciation is thought to be facilitated by escape of early generation hybrids into new habitats, subsequent environmental selection and adaptation. Here, we ask whether two homoploid hybrid plant species (Helianthus anomalus, H. deserticola) diverged sufficiently from their ancestral parent

  5. Terrestrial animals as invasive species and as species at risk from invasions

    Science.gov (United States)

    Deborah M. Finch; Dean Pearson; Joseph Wunderle; Wayne Arendt

    2010-01-01

    Including terrestrial animal species in the invasive species strategy plan is an important step in invasive species management. Invasions by nonindigenous species threaten nearly 50 percent of imperiled native species in the United States and are the Nation's second leading cause of species endangerment. Invasion and conversion of native habitats by exotic species...

  6. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    The stranded weeds constituted a total of 62 species during the entire study period.Of this,Rhodophyta ranked high with 26 species followed by Chlorophyta with 22 species and Phaeophyta with 14 species.The stranded seaweeds that were washed ashore provide valuable floristic information about the intertidal and near ...

  7. Malassezia Species and Pityriasis Versicolor

    Directory of Open Access Journals (Sweden)

    Gulin Rodoplu

    2016-01-01

    Full Text Available Malassezia species are found in part of the normal human cutaneous commensal flora, however it has been known for many years that the Malassezia yeasts are associated with a number of different human diseases ranging from pityriasis versicolor to seborrhoeic dermatitis. In addition, since the 1980s, they have been reported as causing opportunistic systemic infections. The taxonomy of Malassezia spp. has recently been modified to include 13 obligatorily lipophilic species, plus one non-obligatorily lipophilic species, which only rarely colonizes human hosts and currently the genus consist 14 species as M. furfur, M. pachydermatis, M. sympodialis, M. globosa, M. obtusa, M. slooffiae, M. restricta, M. dermatis, M. japonica, M. nana, M. yamatoensis, M. caprae, M. equina, M. cuniculi. Fastidious growth requirements of Malassezia yeasts defied the initial attempts to culture these organisms and their true identification and the relationship between different species only became apparent with the application of modern molecular techniques. The causative fungus is seen especially in such seborrheic areas as the scalp, face, trunk and upper back. Under the influence of various exogenous or endogenous predisposing factors, these yeasts change from the blastospore form to the mycelial form and become pathogenic. Diagnosis of pityriasis versicolor which is caused by Malassezia species is generally easy and lies on the basis of its clinical appearance and can be confirmed by mycological examination. The diagnosisis is mainly based on direct examination with potassium hydroxide (KOH and demonstration that represents pseudohyphae and blastoconidia as the typical %u201Cspaghetti and meatballs%u201D pattern. Characteristic features of the genus Malassezia include a distinctive morphology and an affinity for lipids in culture. Culture is necessary to recover the infecting strain, especially for epidemiologic purposes and also to test its antifungal susceptibility

  8. Especies del Fitoplancton Presentes en el Lago Tonatiahua, Morelos, México Especies del Fitoplancton Presentes en el Lago Tonatiahua, Morelos, México

    Directory of Open Access Journals (Sweden)

    Roberto Trejo Albarrán

    2012-02-01

    Full Text Available Se llevó a cabo un reconocimiento de las especies del fitoplancton del Lago Tonatiahua, Morelos, México, registrándose un total de 24 especies, incluidas en las siguientes clases: Chlorophyceae con 4 especies, Chlamydophyceae con 3 especies, Cyanophyceae con 3 especies, Euglenophyceae con 2 especies, Dinophyceae con 1 especie y Bacillariophyceae con 11, se da una descripción de cada una de ellas y la distribución que presentaron en la columna de agua durante el estudio. An examination of the phytoplankton species from the Tonatiahua lake of Morelos, Mexico was carried out. 24species were examinated. They were included in the following classification: Chlorophyceae with 4species, Chlamydophyceae with 3species, Cyanophyceae with 3 species, Euglenophyceae with 2 species, Dinophyceae with 1 species, Bacillariophyceae with 11 species, a description of each are and its distribution in a water column during the test are presented in this paper.

  9. Turbulent dispersal promotes species coexistence

    Science.gov (United States)

    Berkley, Heather A; Kendall, Bruce E; Mitarai, Satoshi; Siegel, David A

    2010-01-01

    Several recent advances in coexistence theory emphasize the importance of space and dispersal, but focus on average dispersal rates and require spatial heterogeneity, spatio-temporal variability or dispersal-competition tradeoffs to allow coexistence. We analyse a model with stochastic juvenile dispersal (driven by turbulent flow in the coastal ocean) and show that a low-productivity species can coexist with a high-productivity species by having dispersal patterns sufficiently uncorrelated from those of its competitor, even though, on average, dispersal statistics are identical and subsequent demography and competition is spatially homogeneous. This produces a spatial storage effect, with an ephemeral partitioning of a ‘spatial niche’, and is the first demonstration of a physical mechanism for a pure spatiotemporal environmental response. ‘Turbulent coexistence’ is widely applicable to marine species with pelagic larval dispersal and relatively sessile adult life stages (and perhaps some wind-dispersed species) and complements other spatial and temporal storage effects previously documented for such species. PMID:20455921

  10. The complete mitochondrial DNA sequences of Nephroselmis olivacea and Pedinomonas minor. Two radically different evolutionary patterns within green algae.

    Science.gov (United States)

    Turmel, M; Lemieux, C; Burger, G; Lang, B F; Otis, C; Plante, I; Gray, M W

    1999-09-01

    Green plants appear to comprise two sister lineages, Chlorophyta (classes Chlorophyceae, Ulvophyceae, Trebouxiophyceae, and Prasinophyceae) and Streptophyta (Charophyceae and Embryophyta, or land plants). To gain insight into the nature of the ancestral green plant mitochondrial genome, we have sequenced the mitochondrial DNAs (mtDNAs) of Nephroselmis olivacea and Pedinomonas minor. These two green algae are presumptive members of the Prasinophyceae. This class is thought to include descendants of the earliest diverging green algae. We find that Nephroselmis and Pedinomonas mtDNAs differ markedly in size, gene content, and gene organization. Of the green algal mtDNAs sequenced so far, that of Nephroselmis (45,223 bp) is the most ancestral (minimally diverged) and occupies the phylogenetically most basal position within the Chlorophyta. Its repertoire of 69 genes closely resembles that in the mtDNA of Prototheca wickerhamii, a later diverging trebouxiophycean green alga. Three of the Nephroselmis genes (nad10, rpl14, and rnpB) have not been identified in previously sequenced mtDNAs of green algae and land plants. In contrast, the 25,137-bp Pedinomonas mtDNA contains only 22 genes and retains few recognizably ancestral features. In several respects, including gene content and rate of sequence divergence, Pedinomonas mtDNA resembles the reduced mtDNAs of chlamydomonad algae, with which it is robustly affiliated in phylogenetic analyses. Our results confirm the existence of two radically different patterns of mitochondrial genome evolution within the green algae.

  11. Tiarosporella species: Distribution and significance

    Directory of Open Access Journals (Sweden)

    Karadžić Dragan

    2003-01-01

    Full Text Available The genus Tiarosporella consists of eight species of which four occur on conifers. These fungi differ in conidial size and in the form of appendages that occur on the distal end of the conidia (pycnospore. In Europe only the two species have been recorded. T. parca occurs on the species of the genus Picea (P. abies and P. omorika, while T. durmitorensis infests fir (Abies alba. T. parca can be considered, as an endophyte, and it sporulates only when the needles die due to a stress or old age. T. durmitorensis is a very aggressive pathogen colonizing fir needles of all ages. Together with other fungi, it leads to tree death. So far, T. durmitotensis has been found only in European silver fir stands in the National Park "Durmitor" and in the National Park "Biogradska Gora".

  12. Scandinavian Oncophorus (Bryopsida, Oncophoraceae: species, cryptic species, and intraspecific variation

    Directory of Open Access Journals (Sweden)

    Lars Hedenäs

    2017-05-01

    Full Text Available Scandinavian members of the acrocarpous moss genus Oncophorus were revised after field observations had suggested unrecognized diversity. Based on molecular (nuclear: internal transcribed spacers 1 and 2, ITS; plastid: trnGUCC G2 intron, trnG, rps4 gene + trnS-rps4 spacer, rps4 and morphological evidence, four morphologically distinguishable species are recognized, Oncophorus elongatus (I.Hagen Hedenäs, O. integerrimus Hedenäs sp. nov. (syn. O. virens var. elongatus Limpr., O. virens (Hedw. Brid., and O. wahlenbergii Brid. (O. sardous Herzog, syn. nov.. Oncophorus elongatus was earlier recognized, but much of its variation was hidden within O. wahlenbergii. Its circumscription is here expanded to include plants with long leaves having mostly denticulate or sharply denticulate upper margins and with long and narrow marginal cells in the basal portion of the sheathing leaf lamina. The new species O. integerrimus sp. nov. differs from O. virens in having more loosely incurved leaves and entire or almost entire upper leaf margins. Besides these characters, the species in the respective pairs differ in quantitative features of the leaf lamina cells. Several cryptic entities were found, in several cases as molecularly distinct as some of the morphologically recognizable species, and phylogeographic structure is present within O. elongatus and O. virens.

  13. New species of Elattostachys (Blume) Radlk. (Sapindaceae)

    NARCIS (Netherlands)

    Adema, Frits

    1992-01-01

    Seven new species of Elattostachys (Blume) Radlk. are described, five from New Guinea and one each from Celebes and the Solomon Islands. A key to the species of Celebes and one to the species of New Guinea is given.

  14. Enolonium Species-Umpoled Enolates

    DEFF Research Database (Denmark)

    Arava, Shlomy; Kumar, Jayprakash N.; Maksymenko, Shimon

    2017-01-01

    Enolonium species/iodo(III) enolates of carbonyl compounds have been suggested to be intermediates in a wide variety of hypervalent iodine induced chemical transformations of ketones, including α-C-O, α-C-N, α-C-C, and alpha-carbon- halide bond formation, but they have never been characterized. W....... Our results open up chemical space for designing a variety of new transformations. We showcase the ability of enolonium species to react with prenyl, crotyl, cinnamyl, and allyl silanes with absolute regioselectivity in up to 92% yield....

  15. Seven new Malesian species of Ficus (Moraceae)

    NARCIS (Netherlands)

    Berg, C.C.

    2012-01-01

    Descriptions of seven new species, Ficus buntaensis, F. flavistipulata, F. jambiensis, F. porata, F. samarana, F. sorongensis and F. temburongensis are presented and the related species briefly discussed.

  16. Alien species recorded in the United Arab Emirates: an initial list of terrestrial and freshwater species

    Directory of Open Access Journals (Sweden)

    Pritpal Soorae

    2015-10-01

    Full Text Available Little is documented on the alien terrestrial and freshwater species in the United Arab Emirates. To address this, an assessment of terrestrial and freshwater alien species was conducted using various techniques such as a questionnaire, fieldwork data, networking with relevant people, and a detailed literature review. The results of the initial assessment show that there are 146 alien species recorded in the following seven major taxonomic groups: invertebrates 49 species, freshwater fish five species, amphibian one species, reptiles six species, birds 71 species, mammals six species and plants eight species. To inform decision makers a full list of the 146 species identified in this assessment is presented. 

  17. and tulbaghia species (wild garlic)

    African Journals Online (AJOL)

    Mgina

    Tulbaghia (wild Garlic) is a plant genus most closely related to the genus Allium both in the family Alliaceae and is ... that have been identified in the Alliaceae family. ... characteristic odours and the medicinal properties of both the Tulbaghia and Allium species. This review will focus mainly on the genus Tulbaghia and its.

  18. SARS – virus jumps species

    Indian Academy of Sciences (India)

    SARS – virus jumps species. Coronavirus reshuffles genes; Rotteir et al, Rotterdam showed the virus to jump from cats to mouse cells after single gene mutation ? Human disease due to virus jumping from wild or domestic animals; Present favourite animal - the cat; - edible or domestic.

  19. Thromboelastography in Selected Avian Species

    DEFF Research Database (Denmark)

    Andersen, Sophie Susanna Strindberg; Nielsen, Tenna W; Ribeiro, Ângela M

    2015-01-01

    ) (n = 13), helmeted Guinea fowl ( Numida meleagris ) (n = 12), Amazon parrots (Amazona species) (n = 9), Humboldt penguins ( Spheniscus humboldti ) (n = 6), and domestic chickens (n = 16). Activated partial thromboplastin time, prothrombin time, and fibrinogen were measured as a means of comparison...

  20. Molecular Epidemiology of Fonsecaea Species

    NARCIS (Netherlands)

    Najafzadeh, M.J.; Sun, J.; Vicente, V.A.; Klaassen, C.H.W.; Bonifaz, A.; Gerrits van den Ende, A.H.G.; Menken, S.B.J.; de Hoog, G.S.

    2011-01-01

    To assess population diversities among 81 strains of fungi in the genus Fonsecaea that had been identified down to species level, we applied amplified fragment-length polymorphism (AFLP) technology and sequenced the internal transcribed spacer regions and the partial cell division cycle, β-tubulin,

  1. Man...An Endangered Species?

    Science.gov (United States)

    Department of the Interior, Washington, DC.

    The general theme of this 1968 yearbook is that man is a threatened species, facing overpopulation and unbridled technology - both self induced. The presentation is broad, relating to many aspects of conservation and natural resources in the United States in a descriptive, non-technical style. The yearbook is divided into major topics: Land…

  2. Influenza vaccines for avian species

    Science.gov (United States)

    Beginning in Southeast Asia, in 2003, a multi-national epizootic outbreak of H5N1 highly pathogenic avian influenza (HPAI) was identified in commercial poultry and wild bird species. This lineage, originally identified in Southern China in 1996 and then Hong Kong in 1997, caused severe morbidity an...

  3. storey and canopy tree species

    African Journals Online (AJOL)

    different tree species. The data presented here would therefore help in the planning and management of tropical forest reserves and development of management inteiventions to enhance forest productivity and ecological balance. Materials and methods. Study site. Kalinzu Forest Reserve is a tropical rain forest locate<.! in.

  4. The Netherlands’ marine Cladophora species

    NARCIS (Netherlands)

    Slootweg, A.F.G.

    1947-01-01

    When studying the marine species of the genus Cladophora in the Netherlands, I had the disposal of the material of the National Herbarium at Leiden, the herbaria of the Universities of Amsterdam, Groningen and Utrecht and those of the “Zoölogisch Station” at Den Helder and the “Koninklijke

  5. Perpetual flowering in strawberry species

    Science.gov (United States)

    Studies have revealed genetic control of flowering patterns for seasonal flowering (SF) and perpetual flowering (PF) genotypes in the common garden strawberry, with associated links to gene homeologs in diploid alpine strawberry, F. vesca L. Within the genus Fragaria, 22 species and multiple subspec...

  6. Georgia Species at Risk Project

    Science.gov (United States)

    2009-06-01

    well-developed. Shrub and herb layers may be sparse or moderately dense. Within its range, Sabal minor may be a prominent shrub. Species richness...lanuginosa), Ulmus alata and Viburnum rufidulum. Common vines include Berchemia scandens and Cocculus carolinus. This community occurs on

  7. Endangered Species: An Educator's Handbook.

    Science.gov (United States)

    Smith, Jean, M., Comp.

    Presented are two articles, an annotated bibliography, and other information useful in teaching about endangered species, especially those found in Florida. The articles provide an ethical rationale, teaching suggestions, and a discussion of the value of wildlife. Descriptions of over 100 pertinent books, periodicals, movies, and filmstrips are in…

  8. Methylated DNA in Borrelia species.

    OpenAIRE

    Hughes, C A; Johnson, R C

    1990-01-01

    The DNA of Borrelia species was examined for the presence of methylated GATC sequences. The relapsing-fever Borrelia sp., B. coriaceae, and only 3 of 22 strains of B. burgdorferi contained adenine methylation systems. B. anserina lacked an adenine methylation system. Fundamental differences in DNA methylation exist among members of the genus Borrelia.

  9. Species recovery in the united states: Increasing the effectiveness of the endangered species act

    OpenAIRE

    Evans, DM; Che-Castaldo, JP; Crouse, D; Davis, FW; Epanchin-Niell, R; Flather, CH; Frohlich, RK; Goble, DD; Li, YW; Male, TD; Master, LL; Moskwik, MP; Neel, MC; Noon, BR; Parmesan, C

    2016-01-01

    © The Ecological Society of America. The Endangered Species Act (ESA) has succeeded in shielding hundreds of species from extinction and improving species recovery over time. However, recovery for most species officially protected by the ESA - i.e., listed species-has been harder to achieve than initially envisioned. Threats to species are persistent and pervasive, funding has been insufficient, the distribution of money among listed species is highly uneven, and at least 10 times more specie...

  10. Optimal conservation of migratory species.

    Directory of Open Access Journals (Sweden)

    Tara G Martin

    Full Text Available BACKGROUND: Migratory animals comprise a significant portion of biodiversity worldwide with annual investment for their conservation exceeding several billion dollars. Designing effective conservation plans presents enormous challenges. Migratory species are influenced by multiple events across land and sea-regions that are often separated by thousands of kilometres and span international borders. To date, conservation strategies for migratory species fail to take into account how migratory animals are spatially connected between different periods of the annual cycle (i.e. migratory connectivity bringing into question the utility and efficiency of current conservation efforts. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report the first framework for determining an optimal conservation strategy for a migratory species. Employing a decision theoretic approach using dynamic optimization, we address the problem of how to allocate resources for habitat conservation for a Neotropical-Nearctic migratory bird, the American redstart Setophaga ruticilla, whose winter habitat is under threat. Our first conservation strategy used the acquisition of winter habitat based on land cost, relative bird density, and the rate of habitat loss to maximize the abundance of birds on the wintering grounds. Our second strategy maximized bird abundance across the entire range of the species by adding the constraint of maintaining a minimum percentage of birds within each breeding region in North America using information on migratory connectivity as estimated from stable-hydrogen isotopes in feathers. We show that failure to take into account migratory connectivity may doom some regional populations to extinction, whereas including information on migratory connectivity results in the protection of the species across its entire range. CONCLUSIONS/SIGNIFICANCE: We demonstrate that conservation strategies for migratory animals depend critically upon two factors: knowledge of

  11. Species recovery in the United States: Increasing the effectiveness of the Endangered Species Act

    Science.gov (United States)

    Daniel M. Evans; Judy P. Che-Castaldo; Deborah Crouse; Frank W. Davis; Rebecca Epanchin-Niell; Curtis H. Flather; R. Kipp Frohlich; Dale D. Goble; Ya-Wei Li; Timothy D. Male; Lawrence L. Master; Matthew P. Moskwik; Maile C. Neel; Barry R. Noon; Camille Parmesan; Mark W. Schwartz; J. Michael Scott; Byron K. Williams

    2016-01-01

    The Endangered Species Act (ESA) has succeeded in shielding hundreds of species from extinction and improving species recovery over time. However, recovery for most species officially protected by the ESA - i.e., listed species - has been harder to achieve than initially envisioned. Threats to species are persistent and pervasive, funding has been insufficient...

  12. Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic.

    Science.gov (United States)

    Scherner, Fernando; Horta, Paulo Antunes; de Oliveira, Eurico Cabral; Simonassi, José Carlos; Hall-Spencer, Jason M; Chow, Fungyi; Nunes, José Marcos C; Pereira, Sonia Maria Barreto

    2013-11-15

    Coastal urbanization is rapidly expanding worldwide while its impacts on seaweed communities remain poorly understood. We assessed the impact of urbanization along an extensive latitudinal gradient encompassing three phycogeographical regions in the SW Atlantic. Human population density, number of dwellings, and terrestrial vegetation cover were determined for each survey area and correlated with diversity indices calculated from seaweed percent cover data. Urban areas had significantly lower calcareous algal cover (-38%), and there was significantly less carbonate in the sediment off urban areas than off reference areas. Seaweed richness averaged 26% less in urban areas than in areas with higher vegetation cover. We observed a remarkable decline in Phaeophyceae and a substantial increase of Chlorophyta in urban areas across a wide latitudinal gradient. Our data show that coastal urbanization is causing substantial loss of seaweed biodiversity in the SW Atlantic, and is considerably changing seaweed assemblages. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Synopsis of the Oxyethira flavicornis species group with new Japanese Oxyethira species (Trichoptera, Hydroptilidae

    Directory of Open Access Journals (Sweden)

    Oláh, J.

    2013-06-01

    Full Text Available A brief synopsis of the Oxyethira flavicornis species group is produced by the examination of type materials. Diagrammatic drawings with similar style were prepared for all the known and for the new species. Short description of genus Oxyethira, subgenus Oxyethira, species group of Oxyethira flavicornis are presented together with the description of five species clusters: O. datra new species cluster, O. ecornuta new species cluster, O. flavicornis new species cluster, O. hiroshima new species cluster, O. tiunovae new species cluster. Five new species are described from the O. flavicornis species group: O chitosea sp. n., O. hena sp. n., O. hiroshima sp. n., O. kakida sp. n., O. mekunna sp. n. One new species is described from the Oxyethira grisea species group: Oxyethira ozea sp. n. and two new species from the Oxyethira ramosa species group: Oxyethira miea sp. n., Oxyethira okinawa sp. n.

  14. Allelopathy of plant species of pharmaceutical importance to cultivated species

    Directory of Open Access Journals (Sweden)

    Álisson Sobrinho Maranho

    2012-11-01

    Full Text Available This study aimed to identify possible allelopathic effects of leaf aqueous extracts of Baccharis dracunculifolia DC., Pilocarpus pennatifolius Lem., Cyperus rotundus L., Morus rubra L., Casearia sylvestris Sw., and Plectranthus barbatus Andr. on the germination and initial growth of Lactuca sativa L., Brassica oleracea L. cv. capitata, B. oleracea L. cv. italica, B. pekinenses L., B. campestris L., Lycopersicum esculentum Miller, and Eruca sativa L. To obtain the aqueous extracts, leaves previously dried at a 1g.10mL-1 concentration were used, diluted in six solutions (10, 30, 50, 70, 90, and 100% and compared to control, distilled water, with five replications of 10 seeds for all vegetable species. The aqueous extracts of all species showed allelopathic potential for germination of seeds, the germination speed index, and the initial growth of shoots and roots of vegetable crops. The aqueous extracts of C. rotundus and P. barbatus promoted lower and higher allelopathic effects, respectively, and the vegetal structure mostly affected by the extracts was the primary root. The results indicate the existence of allelopathic potential in the species tested, so there’s a need for adopting care procedures when cultivating vegetables with them.

  15. Estrutura da comunidade de Chlorococcales sensu lato (Chlorophyceae em diferentes hábitats aquáticos e hidroperíodos Structure of the Chlorococcales sensu lato (Chlorophyceae community in different aquatic habitats and hydroperiods

    Directory of Open Access Journals (Sweden)

    Lezilda Carvalho Torgan

    2011-03-01

    Full Text Available Este estudo visa avaliar a riqueza, a densidade, a diversidade específica e a distribuição da comunidade de Chlorococcales s.l. em zonas pelágicas e litorâneas de diferentes hábitats aquáticos (lagoas isoladas, lagoas interligadas, banhados, açudes e arroios em dois hidroperíodos (águas altas e baixas em região subtropical no sul do Brasil. As amostragens de fitoplâncton foram realizadas em duas áreas, situadas entre as coordenadas 30(040´ - 30(010´ S e 50(030´ - 51(031´W no ano de 2003, com a obtenção simultânea de dados de temperatura, condutividade, pH, transparência e profundidade da água. Os resultados revelaram que as médias de riqueza e de diversidade específica foram maiores na zona litorânea e significativamente maiores (p24°C. Dentre os táxons observados, Desmodesmus heteracanthus (Guerr. Hentschke et Torgan, D. lunatus (W. et G. S. West Hegew. e Monoraphidium griffithii (Berk. Kom-Legn., mostraram-se indicadoras de hábitats e D. armatus (Chod. Hegew., D. denticulatus (Lagerh. An, Friedl et Hegew. e D. lunatus foram indicadoras de hidroperíodo. Este estudo demonstra a importância do hábitat e do hidroperíodo, na estrutura da comunidade de Chlorococcales s.l.This study aims to evaluate richness, density specific diversity and distribution of the Chlorococcales s.l. community in pelagic and littoral zones of different aquatic habitats (isolated lagoons, interlinked lagoons, swamps, reservoirs and streams during two hydroperiods (high and low water in a subtropical region in Southern Brazil. Phytoplankton sampling was carried out in two areas, situated within the coordinates 30(040´ - 30(010´ S and 50(030´ - 51(031´ W, in 2003 with simultaneous information on temperature, conductivity, pH, transparency and depth of water. The results showed that richness and specific diversity averages were higher in the littoral zone and significantly higher (p24°C. Among the observed taxa Desmodesmus heteracanthus (Guerr. Hentschke & Torgan, D. lunatus (W. et G. S. West Hegew. and Monoraphidium griffithii (Berk. Kom-Legn. were habitat indicators and D. armatus (Chod. Hegew., D. denticulatus (Lagerh. An, Friedl et Hegew. and D. lunatus were hydroperiod indicators. This study shows the importance of habitats and hydroperiods for Chlorococcales s.l. community structure.

  16. Floral reward in Ranunculaceae species

    Directory of Open Access Journals (Sweden)

    Bożena Denisow

    2016-04-01

    Full Text Available Floral reward is important in ecological and evolutionary perspectives and essential in pollination biology. For example, floral traits, nectar and pollen features are essential for understanding the functional ecology, the dynamics of pollen transport, competition for pollinator services, and patterns of specialization and generalization in plant–pollinator interactions. We believe to present a synthetic description in the field of floral reward in Ranunculaceae family important in pollination biology and indicating connections between ecological and evolutionary approaches. The links between insect visitors’ behaviour and floral reward type and characteristics exist. Ranunculaceae is a family of aboot 1700 species (aboot 60 genera, distributed worldwide, however the most abundant representatives are in temperate and cool regions of the northern and southern hemispheres. The flowers are usually radially symmetric (zygomorphic and bisexual, but in Aconitum, Aquilegia are bilaterally symmetric (zygomorphic. Most Ranunculaceae flowers offer no nectar, only pollen (e.g., Ranunculus, Adonis vernalis, Thalictrum, but numerous species create trophic niches for different wild pollinators (e.g. Osmia, Megachile, Bombus, Andrena (Denisow et al. 2008. Pollen is a source of protein, vitamins, mineral salts, organic acids and hormones, but the nutritional value varies greatly between different plant species. The pollen production can differ significantly between Ranunculacea species. The mass of pollen produced in anthers differ due to variations in the number of developed anthers. For example, interspecies differences are considerable, 49 anthers are noted in Aquilegia vulgaris, 70 anthers in Ranunculus lanuginosus, 120 in Adonis vernalis. A significant intra-species differences’ in the number of anthers are also noted (e.g. 41 to 61 in Aquilegia vulgaris, 23-45 in Ranunculus cassubicus. Pollen production can be up to 62 kg per ha for Ranunculus acer

  17. The myth of plant species saturation

    Science.gov (United States)

    Thomas J. Stohlgren; David T. Barnett; Catherine S. Jarnevich; Curtis Flather; John Kartesz

    2008-01-01

    Plant species assemblages, communities or regional floras might be termed saturated when additional immigrant species are unsuccessful at establishing due to competitive exclusion or other inter-specific interactions, or when the immigration of species is off-set by extirpation of species. This is clearly not the case for state, regional or national floras in the USA...

  18. What is a Species? An Endless Debate

    Indian Academy of Sciences (India)

    Srimath

    compatibility. Hennigian species. Hennig, 1950. Species are reproductively isolated natural concept. Willmann, 1985 populations or group of populations. They originate via the dissolution of the stem species in speciation event and cease to exist either through extinction or speciation. Ecological species. Van Valen, 1976.

  19. Charcoal anatomy of forest species

    Directory of Open Access Journals (Sweden)

    Graciela Inés Bolzon de Muñiz1

    2012-09-01

    Full Text Available Vegetal charcoal retains the anatomical structure of the wood and may permit its botanical identification, which depends on species characteristics, the charcoal fragments size and preservation state. Anatomical characterization of ten forest species charcoal was done envisaging the identification and control of illegal charcoal. Differences between gymnosperms and angiosperms are evident in carbonized wood. Vessel diameter was statistically different between wood and charcoal in Vatairea guianensis, Mezilaurus itauba, Calophyllum brasiliense e Qualea cf. acuminata, and vessel frequency in Vatairea guianensis, Manilkara huberi, Qualea cf. acuminata e Simarouba amara. The anatomical structure from wood, in general aspects, is constant during carbonization process using temperature of 450°C, being possible to identify the material by using its cellular components.

  20. Dynamic conservation for migratory species.

    Science.gov (United States)

    Reynolds, Mark D; Sullivan, Brian L; Hallstein, Eric; Matsumoto, Sandra; Kelling, Steve; Merrifield, Matthew; Fink, Daniel; Johnston, Alison; Hochachka, Wesley M; Bruns, Nicholas E; Reiter, Matthew E; Veloz, Sam; Hickey, Catherine; Elliott, Nathan; Martin, Leslie; Fitzpatrick, John W; Spraycar, Paul; Golet, Gregory H; McColl, Christopher; Morrison, Scott A

    2017-08-01

    In an era of unprecedented and rapid global change, dynamic conservation strategies that tailor the delivery of habitat to when and where it is most needed can be critical for the persistence of species, especially those with diverse and dispersed habitat requirements. We demonstrate the effectiveness of such a strategy for migratory waterbirds. We analyzed citizen science and satellite data to develop predictive models of bird populations and the availability of wetlands, which we used to determine temporal and spatial gaps in habitat during a vital stage of the annual migration. We then filled those gaps using a reverse auction marketplace to incent qualifying landowners to create temporary wetlands on their properties. This approach is a cost-effective way of adaptively meeting habitat needs for migratory species, optimizes conservation outcomes relative to investment, and can be applied broadly to other conservation challenges.

  1. Echinococcus species in African wildlife.

    Science.gov (United States)

    Hüttner, M; Romig, T

    2009-09-01

    Cystic echinococcosis, caused by different species of the Echinococcus granulosus complex, is an important zoonotic disease with a particular impact on pastoralist societies. In addition to the widespread taxa with synanthropic transmission, a number of Echinococcus species were described from African wild carnivores early in the 20th century. For lack of study material, most of these were later tentatively synonymized with E. granulosus. Early infection experiments with wildlife isolates gave ambiguous results due to the use of unspecified parasite material, and only recently molecular methods provided the opportunity to shed light on the confusing scenery e.g. by characterizing E. felidis from the African lion. Here we will summarize the convoluted history of Echinococcus research in sub-Saharan Africa and highlight the necessity of molecular surveys to establish the life cycles and estimate the zoonotic potential of these parasites.

  2. Ranking species in mutualistic networks

    Science.gov (United States)

    Domínguez-García, Virginia; Muñoz, Miguel A.

    2015-02-01

    Understanding the architectural subtleties of ecological networks, believed to confer them enhanced stability and robustness, is a subject of outmost relevance. Mutualistic interactions have been profusely studied and their corresponding bipartite networks, such as plant-pollinator networks, have been reported to exhibit a characteristic ``nested'' structure. Assessing the importance of any given species in mutualistic networks is a key task when evaluating extinction risks and possible cascade effects. Inspired in a recently introduced algorithm -similar in spirit to Google's PageRank but with a built-in non-linearity- here we propose a method which -by exploiting their nested architecture- allows us to derive a sound ranking of species importance in mutualistic networks. This method clearly outperforms other existing ranking schemes and can become very useful for ecosystem management and biodiversity preservation, where decisions on what aspects of ecosystems to explicitly protect need to be made.

  3. Haemolytic glycoglycerolipids from Gymnodinium species.

    Science.gov (United States)

    Parrish, C C; Bodennec, G; Gentien, P

    1998-03-01

    Glycoglycerolipids derived from microalgae can be a source of biologically active substances including toxins. Such glycolipids were analysed in two isolates of toxic marine dinoflagellates from European waters. The lipids of Gymnodinium mikimotoi contained 17% of monogalactosyl diacylglycerol (MGDG) and digalactosyl diacylglycerol (DGDG), while in Gymnodinium sp. the proportion was 35%. MGDG and DGDG from both species were haemolytic. The major unsaturated fatty acid in both algal glycolipids was 18:5 omega 3.

  4. Population Genomics of Paramecium Species.

    Science.gov (United States)

    Johri, Parul; Krenek, Sascha; Marinov, Georgi K; Doak, Thomas G; Berendonk, Thomas U; Lynch, Michael

    2017-05-01

    Population-genomic analyses are essential to understanding factors shaping genomic variation and lineage-specific sequence constraints. The dearth of such analyses for unicellular eukaryotes prompted us to assess genomic variation in Paramecium, one of the most well-studied ciliate genera. The Paramecium aurelia complex consists of ∼15 morphologically indistinguishable species that diverged subsequent to two rounds of whole-genome duplications (WGDs, as long as 320 MYA) and possess extremely streamlined genomes. We examine patterns of both nuclear and mitochondrial polymorphism, by sequencing whole genomes of 10-13 worldwide isolates of each of three species belonging to the P. aurelia complex: P. tetraurelia, P. biaurelia, P. sexaurelia, as well as two outgroup species that do not share the WGDs: P. caudatum and P. multimicronucleatum. An apparent absence of global geographic population structure suggests continuous or recent dispersal of Paramecium over long distances. Intergenic regions are highly constrained relative to coding sequences, especially in P. caudatum and P. multimicronucleatum that have shorter intergenic distances. Sequence diversity and divergence are reduced up to ∼100-150 bp both upstream and downstream of genes, suggesting strong constraints imposed by the presence of densely packed regulatory modules. In addition, comparison of sequence variation at non-synonymous and synonymous sites suggests similar recent selective pressures on paralogs within and orthologs across the deeply diverging species. This study presents the first genome-wide population-genomic analysis in ciliates and provides a valuable resource for future studies in evolutionary and functional genetics in Paramecium. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Candida Species Biofilms’ Antifungal Resistance

    Science.gov (United States)

    Silva, Sónia; Rodrigues, Célia F.; Araújo, Daniela; Rodrigues, Maria Elisa; Henriques, Mariana

    2017-01-01

    Candida infections (candidiasis) are the most prevalent opportunistic fungal infection on humans and, as such, a major public health problem. In recent decades, candidiasis has been associated to Candida species other than Candida albicans. Moreover, biofilms have been considered the most prevalent growth form of Candida cells and a strong causative agent of the intensification of antifungal resistance. As yet, no specific resistance factor has been identified as the sole responsible for the increased recalcitrance to antifungal agents exhibited by biofilms. Instead, biofilm antifungal resistance is a complex multifactorial phenomenon, which still remains to be fully elucidated and understood. The different mechanisms, which may be responsible for the intrinsic resistance of Candida species biofilms, include the high density of cells within the biofilm, the growth and nutrient limitation, the effects of the biofilm matrix, the presence of persister cells, the antifungal resistance gene expression and the increase of sterols on the membrane of biofilm cells. Thus, this review intends to provide information on the recent advances about Candida species biofilm antifungal resistance and its implication on intensification of the candidiasis. PMID:29371527

  6. Endophthalmitis caused by Klebsiella species.

    Science.gov (United States)

    Sridhar, Jayanth; Flynn, Harry W; Kuriyan, Ajay E; Dubovy, Sander; Miller, Darlene

    2014-09-01

    To report the clinical presentation, antibiotic sensitivities, treatment strategies, and visual outcomes associated with endophthalmitis caused by Klebsiella species. A noncomparative consecutive case series. Microbiology database records were retrospectively reviewed for all patients with endophthalmitis caused by Klebsiella species from 1990 to 2012 at a large university referral center. The corresponding clinical records were then reviewed to evaluate the endophthalmitis clinical features and treatment outcomes. Seven patients were identified. Clinical settings included endogenous (n = 3), posttraumatic (n = 2), trabeculectomy bleb-associated (n = 1), and postpenetrating keratoplasty (n = 1). Five patients presented with hypopyon. Presenting visual acuity ranged from 20/60 to light perception in nonendogenous cases and 1/200 to light perception in endogenous cases. Klebsiella was sensitive to aminoglycosides, third-generation cephalosporins, and second- and third-generation fluoroquinolones in all cases. Initial treatment strategies were vitreous tap and injection (n = 4), pars plana vitrectomy with intravitreal antibiotics (n = 2), and anterior chamber tap and injection (n = 1). All three endogenous cases later underwent enucleation or evisceration. In nonendogenous cases, the final visual acuity was 20/70 or better in all 4 patients. Endophthalmitis caused by Klebsiella species is associated with poor visual outcomes. Endogenous cases had high rates of enucleation or evisceration.

  7. Could there be a superhuman species?

    OpenAIRE

    Oderberg, David S.

    2014-01-01

    Transhumanism is the school of thought that advocates the use of technology to enhance the human species, to the point where some supporters consider that a new species altogether could arise. Even some critics think this at least a technological possibility. Some supporters also believe the emergence of a new, improved, superhuman species raises no special ethical questions. Through an examination of the metaphysics of species, and an analysis of the essence of the human species, I argue tha...

  8. Carotenoid and fatty acid compositions of an indigenous Ettlia texensis isolate (Chlorophyceae) under phototrophic and mixotrophic conditions.

    Science.gov (United States)

    Yıldırım, Arzu; Demirel, Zeliha; İşleten-Hoşoğlu, Müge; Akgün, İsmail Hakkı; Hatipoğlu-Uslu, Sevde; Conk-Dalay, Meltem

    2014-02-01

    Ettlia oleoabundance (formerly known as Neochloris oleoabundance) is an attractive candidate for biodiesel production because of its high lipid accumulation, and it's taking the majority of the attention among the strains of Ettlia genus; however, potential of the other genus members is unknown. An indigenous strain from Salda Lake (South West Turkey) identified by 18S rDNA sequencing as Ettlia texensis (GenBank accession no: JQ038221), and its fatty acid and carotenoid compositions under phototrophic and mixotrophic conditions was investigated to evaluate the potential of the strain for commercial uses. A threefold increase was observed in total lipid content (total fatty acids; from 13% to 37%) in mixotrophic culture respect to the phototrophic growth conditions. The oleic acid (C18:1) and alpha-linolenic acid (18:3) were the major unsaturated fatty acids accounting for 40% and 13.2% of total fatty acids in mixotrophic culture, respectively. Carotenoid analyses of the mixotrophic culture revealed the metabolite canthaxanthin, a commercially valuable carotenoid used mainly for food coloring, was the major constituent among other pigments. The possible use of E. texensis in biotechnological applications is discussed.

  9. The nucleocytosolic and chloroplast cycle in the green chlorococcal alga Scenedesmus obliquus (Chlorophyceae, Chlorococcales) grown under various temperatures

    Czech Academy of Sciences Publication Activity Database

    Cepák, Vladislav; Přibyl, Pavel; Vítová, Milada; Zachleder, Vilém

    2007-01-01

    Roč. 46, č. 3 (2007), s. 263-269 ISSN 0031-8884 R&D Projects: GA MŠk ME 575; GA ČR(CZ) GA204/03/1113; GA MŠk(CZ) 1M0571 Institutional research plan: CEZ:AV0Z60050516; CEZ:AV0Z50200510 Keywords : Scenedesmus * cell cycle * temperature Subject RIV: EF - Botanics Impact factor: 1.358, year: 2007

  10. Assessment of key biological and engineering design parameters for production of Chlorella zofingiensis (Chlorophyceae) in outdoor photobioreactors.

    Science.gov (United States)

    Zemke, Peter E; Sommerfeld, Milton R; Hu, Qiang

    2013-06-01

    For the design of a large field of vertical flat plate photobioreactors (PBRs), the effect of four design parameters-initial biomass concentration, optical path length, spacing, and orientation of PBRs-on the biochemical composition and productivity of Chlorella zofingiensis was investigated. A two-stage batch process was assumed in which inoculum is generated under nitrogen-sufficient conditions, followed by accumulation of lipids and carbohydrates in nitrogen-deplete conditions. For nitrogen-deplete conditions, productivity was the most sensitive to initial biomass concentration, as it affects the light availability to individual cells in the culture. An initial areal cell concentration of 50 g m(-2) inoculated into 3.8-cm optical path PBR resulted in the maximum production of lipids (2.42 ± 0.02 g m(-2) day(-1)) and carbohydrates (3.23 ± 0.21 g m(-2) day(-1)). Productivity was less sensitive to optical path length. Optical path lengths of 4.8 and 8.4 cm resulted in similar areal productivities (biomass, carbohydrate, and lipid) that were 20 % higher than a 2.4-cm optical path length. Under nitrogen-sufficient conditions, biomass productivity was 48 % higher in PBRs facing north-south during the winter compared to east-west, but orientation had little influence on biomass productivity during the spring and summer despite large differences in insolation. An optimal spacing could not be determined based on growth alone because a tradeoff was observed in which volumetric and PBR productivity increased as space between PBRs increased, but land productivity decreased.

  11. A curious occurrence of Hazenia broadyi spec. nova in Antarctica and the review of the genus Hazenia (Ulotrichales, Chlorophyceae)

    Czech Academy of Sciences Publication Activity Database

    Škaloud, P.; Nedbalová, Linda; Elster, Josef; Komárek, Jiří

    2013-01-01

    Roč. 36, č. 9 (2013), s. 1281-1291 ISSN 0722-4060 R&D Projects: GA MŠk ME 945 Institutional support: RVO:67985939 Keywords : Antarctica * green algae * lakes Subject RIV: EH - Ecology, Behaviour Impact factor: 2.071, year: 2013

  12. Xanthophyll cycle activity and photosynthesis of Dunaliella tertiolecta (Chlorophyceae) and Thalassiosira weissflogii (Bacillariophyceae) during fluctuating solar radiation

    NARCIS (Netherlands)

    van de Poll, Willem H.; Buma, Anita G. J.; Visser, Ronald J. W.; Janknegt, Paul J.; Villafane, Virginia E.; Helbling, E. Walter

    Short-term ultraviolet (UV) radiation (280-400 nm) effects on xanthophyll cycle activity and photosynthesis were assessed during fluctuating irradiance (60- and 10-min cycles - saturating irradiance to near-zero irradiance) for the marine algae Thalassiosira (Bacillariophyceae) and Dunaliella

  13. Seasonal and diel changes in photosynthetic activity of the snow algae Chlamydomonas nivalis (Chlorophyceae) from Svalbard determined by PAM fluorometry

    Czech Academy of Sciences Publication Activity Database

    Stibal, Marek; Elster, Josef; Šabacká, Marie; Kaštovská, Klára

    2007-01-01

    Roč. 59, - (2007), s. 265-273 ISSN 0168-6496 R&D Projects: GA AV ČR KJB6005409 Institutional research plan: CEZ:AV0Z60050516 Keywords : Chlamydomonas nivalis * photosynthetic activity * PAM fluorometry Subject RIV: EF - Botanics Impact factor: 3.039, year: 2007

  14. A study of the native cell wall structures of the marine alga Ventricaria ventricosa (Siphonocladales, Chlorophyceae) using atomic force microscopy.

    Science.gov (United States)

    Eslick, Enid M; Beilby, Mary J; Moon, Anthony R

    2014-04-01

    A substantial proportion of the architecture of the plant cell wall remains unknown with a few cell wall models being proposed. Moreover, even less is known about the green algal cell wall. Techniques that allow direct visualization of the cell wall in as near to its native state are of importance in unravelling the spatial arrangement of cell wall structures and hence in the development of cell wall models. Atomic force microscopy (AFM) was used to image the native cell wall of living cells of Ventricaria ventricosa (V. ventricosa) at high resolution under physiological conditions. The cell wall polymers were identified mainly qualitatively via their structural appearance. The cellulose microfibrils (CMFs) were easily recognizable and the imaging results indicate that the V. ventricosa cell wall has a cross-fibrillar structure throughout. We found the native wall to be abundant in matrix polysaccharides existing in different curing states. The soft phase matrix polysaccharides susceptible by the AFM scanning tip existed as a glutinous fibrillar meshwork, possibly incorporating both the pectic- and hemicellulosic-type substances. The hard phase matrix producing clearer images, revealed coiled fibrillar structures associated with CMFs, sometimes being resolved as globular structures by the AFM tip. The coiling fibrillar structures were also seen in the images of isolated cell wall fragments. The mucilaginous component of the wall was discernible from the gelatinous cell wall matrix as it formed microstructural domains over the surface. AFM has been successful in imaging the native cell wall and revealing novel findings such as the 'coiling fibrillar structures' and cell wall components which have previously not been seen, that is, the gelatinous matrix phase.

  15. Linking Keystone Species and Functional Groups: A New Operational Definition of the Keystone Species Concept

    OpenAIRE

    Robert D. Davic

    2003-01-01

    The concept of the "keystone species" is redefined to allow for the a priori prediction of these species within ecosystems. A keystone species is held to be a strongly interacting species whose top-down effect on species diversity and competition is large relative to its biomass dominance within a functional group. This operational definition links the community importance of keystone species to a specific ecosystem process, e.g., the regulation of species diversity, within functional groups ...

  16. Plant Species Sensitivity Distributions for ozone exposure

    International Nuclear Information System (INIS)

    Goethem, T.M.W.J. van; Azevedo, L.B.; Zelm, R. van; Hayes, F.; Ashmore, M.R.; Huijbregts, M.A.J.

    2013-01-01

    This study derived Species Sensitivity Distributions (SSD), representing a cumulative stressor-response distribution based on single-species sensitivity data, for ozone exposure on natural vegetation. SSDs were constructed for three species groups, i.e. trees, annual grassland and perennial grassland species, using species-specific exposure–response data. The SSDs were applied in two ways. First, critical levels were calculated for each species group and compared to current critical levels for ozone exposure. Second, spatially explicit estimates of the potentially affected fraction of plant species in Northwestern Europe were calculated, based on ambient ozone concentrations. We found that the SSD-based critical levels were lower than for the current critical levels for ozone exposure, with conventional critical levels for ozone relating to 8–20% affected plant species. Our study shows that the SSD concept can be successfully applied to both derive critical ozone levels and estimate the potentially affected species fraction of plant communities along specific ozone gradients. -- Highlights: ► Plant Species Sensitivity Distributions were derived for ozone exposure. ► Annual grassland species, as a species assemblage, tend to be most sensitive to ozone. ► Conventional critical levels for ozone relate to 8–20% affected plant species. ► The affected fraction of plant species for current ozone exposure in Northwestern Europe is estimated. -- Species Sensitivity Distributions offer opportunities in ozone risk assessment to both derive critical levels and estimate the affected fraction of a plant community

  17. Alien species in the Finnish weed flora

    Directory of Open Access Journals (Sweden)

    T. HYVÖNEN

    2008-12-01

    Full Text Available The present study aimed at assessing the invasion of alien weed species in Finland based on a review of their occurrence in the Finnish weed flora. The evaluation was conducted for the three phases of the invasion process, i.e. introduction, naturalization and invasion. The literature review revealed that 815 alien weed species occur in Finland of which 314 are regarded as naturalized. Based on their occurrence in different climate zones, the risk of naturalization of new harmful alien weed species was deemed low for those species not currently found in Finland, but higher for species occurring as casual aliens in Finland. In the latter group, 10 species of concern were detected. Exploration of the distribution patterns of naturalized species within Finland revealed species occupancy to be dependent on the residence time of the species. Established neophytes can be expected to extend their ranges and to increase occupation of agricultural habitats in the future.;

  18. Natural Constraints to Species Diversification.

    Directory of Open Access Journals (Sweden)

    Eric Lewitus

    2016-08-01

    Full Text Available Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the

  19. The Invasive Species Forecasting System

    Science.gov (United States)

    Schnase, John; Most, Neal; Gill, Roger; Ma, Peter

    2011-01-01

    The Invasive Species Forecasting System (ISFS) provides computational support for the generic work processes found in many regional-scale ecosystem modeling applications. Decision support tools built using ISFS allow a user to load point occurrence field sample data for a plant species of interest and quickly generate habitat suitability maps for geographic regions of management concern, such as a national park, monument, forest, or refuge. This type of decision product helps resource managers plan invasive species protection, monitoring, and control strategies for the lands they manage. Until now, scientists and resource managers have lacked the data-assembly and computing capabilities to produce these maps quickly and cost efficiently. ISFS focuses on regional-scale habitat suitability modeling for invasive terrestrial plants. ISFS s component architecture emphasizes simplicity and adaptability. Its core services can be easily adapted to produce model-based decision support tools tailored to particular parks, monuments, forests, refuges, and related management units. ISFS can be used to build standalone run-time tools that require no connection to the Internet, as well as fully Internet-based decision support applications. ISFS provides the core data structures, operating system interfaces, network interfaces, and inter-component constraints comprising the canonical workflow for habitat suitability modeling. The predictors, analysis methods, and geographic extents involved in any particular model run are elements of the user space and arbitrarily configurable by the user. ISFS provides small, lightweight, readily hardened core components of general utility. These components can be adapted to unanticipated uses, are tailorable, and require at most a loosely coupled, nonproprietary connection to the Web. Users can invoke capabilities from a command line; programmers can integrate ISFS's core components into more complex systems and services. Taken together, these

  20. Natural Constraints to Species Diversification.

    Science.gov (United States)

    Lewitus, Eric; Morlon, Hélène

    2016-08-01

    Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades) within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the deep-time evolution of

  1. Crystallite sizes of porites species

    International Nuclear Information System (INIS)

    Fadhlia Zafarina Zakaria; Julynnie Wajir; Fauziah Abdul Aziz

    2009-01-01

    This study was designed to investigate the crystallite sizes of Porites species. A set of 9 Porites skeletons i.e. Porites australiensis, Porites cylindrica, Porites lutea, Porites lichen, Porites digitata, Porites nigrescens, Porites rus, Porites annae and Porites sp. were studied by using X-Ray Diffraction method. The values of FWHM and theta (θ) are used in Scherrer equation to determine the crystallite sizes of all Porites samples. It was found that the crystallite sizes were in the range of 1000.78 - 1706.04 Angstrom. (author)

  2. VIDAS Listeria species Xpress (LSX).

    Science.gov (United States)

    Johnson, Ronald; Mills, John

    2013-01-01

    The AOAC GovVal study compared the VIDAS Listeria species Xpress (LSX) to the Health Products and Food Branch MFHPB-30 reference method for detection of Listeria on stainless steel. The LSX method utilizes a novel and proprietary enrichment media, Listeria Xpress broth, enabling detection of Listeria species in environmental samples with the automated VIDAS in a minimum of 26 h. The LSX method also includes the use of the chromogenic media, chromID Ottaviani Agosti Agar (OAA) and chromID Lmono for confirmation of LSX presumptive results. In previous AOAC validation studies comparing VIDAS LSX to the U.S. Food and Drug Administration's Bacteriological Analytical Manual (FDA-BAM) and the U.S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) reference methods, the LSX method was approved as AOAC Official Method 2010.02 for the detection of Listeria species in dairy products, vegetables, seafood, raw meats and poultry, and processed meats and poultry, and as AOAC Performance Tested Method 100501 in a variety of foods and on environmental surfaces. The GovVal comparative study included 20 replicate test portions each at two contamination levels for stainless steel where fractionally positive results (5-15 positive results/20 replicate portions tested) were obtained by at least one method at one level. Five uncontaminated controls were included. In the stainless steel artificially contaminated surface study, there were 25 confirmed positives by the VIDAS LSX assay and 22 confirmed positives by the standard culture methods. Chi-square analysis indicated no statistical differences between the VIDAS LSX method and the MFHPB-30 standard methods at the 5% level of significance. Confirmation of presumptive LSX results with the chromogenic OAA and Lmono media was shown to be equivalent to the appropriate reference method agars. The data in this study demonstrate that the VIDAS LSX method is an acceptable alternative method to the MFHPB-30 standard

  3. Arsenic Detoxification by Geobacter Species.

    Science.gov (United States)

    Dang, Yan; Walker, David J F; Vautour, Kaitlin E; Dixon, Steven; Holmes, Dawn E

    2017-02-15

    Insight into the mechanisms for arsenic detoxification by Geobacter species is expected to improve the understanding of global cycling of arsenic in iron-rich subsurface sedimentary environments. Analysis of 14 different Geobacter genomes showed that all of these species have genes coding for an arsenic detoxification system (ars operon), and several have genes required for arsenic respiration (arr operon) and methylation (arsM). Genes encoding four arsenic repressor-like proteins were detected in the genome of G. sulfurreducens; however, only one (ArsR1) regulated transcription of the ars operon. Elimination of arsR1 from the G. sulfurreducens chromosome resulted in enhanced transcription of genes coding for the arsenic efflux pump (Acr3) and arsenate reductase (ArsC). When the gene coding for Acr3 was deleted, cells were not able to grow in the presence of either the oxidized or reduced form of arsenic, while arsC deletion mutants could grow in the presence of arsenite but not arsenate. These studies shed light on how Geobacter influences arsenic mobility in anoxic sediments and may help us develop methods to remediate arsenic contamination in the subsurface. This study examines arsenic transformation mechanisms utilized by Geobacter, a genus of iron-reducing bacteria that are predominant in many anoxic iron-rich subsurface environments. Geobacter species play a major role in microbially mediated arsenic release from metal hydroxides in the subsurface. This release raises arsenic concentrations in drinking water to levels that are high enough to cause major health problems. Therefore, information obtained from studies of Geobacter should shed light on arsenic cycling in iron-rich subsurface sedimentary environments, which may help reduce arsenic-associated illnesses. These studies should also help in the development of biosensors that can be used to detect arsenic contaminants in anoxic subsurface environments. We examined 14 different Geobacter genomes and found

  4. Reactive oxygen species in periodontitis

    Directory of Open Access Journals (Sweden)

    Parveen Dahiya

    2013-01-01

    Full Text Available Recent epidemiological studies reveal that more than two-third of the world′s population suffers from one of the chronic forms of periodontal disease. The primary etiological agent of this inflammatory disease is a polymicrobial complex, predominantly Gram negative anaerobic or facultative bacteria within the sub-gingival biofilm. These bacterial species initiate the production of various cytokines such as interleukin-8 and TNF-α, further causing an increase in number and activity of polymorphonucleocytes (PMN along with these cytokines, PMNs also produce reactive oxygen species (ROS superoxide via the respiratory burst mechanism as the part of the defence response to infection. ROS just like the interleukins have deleterious effects on tissue cells when produced in excess. To counter the harmful effects of ROS, human body has its own defence mechanisms to eliminate them as soon as they are formed. The aim of this review is to focus on the role of different free radicals, ROS, and antioxidants in the pathophysiology of periodontal tissue destruction.

  5. Phytochemistry of European Primula species.

    Science.gov (United States)

    Colombo, Paola S; Flamini, Guido; Rodondi, Graziella; Giuliani, Claudia; Santagostini, Laura; Fico, Gelsomina

    2017-11-01

    The genus Primula is the largest among the Primulaceae and is widespread mainly in the cold and temperate regions of the Northern Hemisphere. Since the beginning of the Twentieth century, several studies on the phytochemical composition of different species of Primula have been carried out. The main constituents examined were tissue and epicuticular flavonoids and saponins, which are of therapeutic significance. Only in recent years studies of the volatiles emitted by leaves and flowers have been carried out as well, but they are restricted to a small number of species. Only a few authors have documented the morphology and function of glandular trichomes in relation to the production of flavonoids and volatile organic compounds (VOCs). The use of Primula in folk medicine is described in the literature. Investigation of the biological and pharmacological activities of Primula are reported. This study aims at providing a collection of publications on the genus Primula along with a critical revision of literature data. It focuses on the possible taxonomic significance of the secondary metabolites and on their ecological role as attractors for pollinators and deterrents against herbivores and parasites, in order to build the base for further studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. SIS - Species and Stock Administrative Data Set

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Species and Stock Administrative data set within the Species Information System (SIS) defines entities within the database that serve as the basis for recording...

  7. Genome size differences in Hyalella cryptic species.

    Science.gov (United States)

    Vergilino, Roland; Dionne, Kaven; Nozais, Christian; Dufresne, France; Belzile, Claude

    2012-02-01

    The Hyalella azteca (Saussure) complex includes numerous amphipod cryptic species in freshwater habitats in America as revealed by DNA barcoding surveys. Two ecomorphs (small and large) have evolved numerous times in this complex. Few phenotypic criteria have been found to differentiate between the numerous species of this complex. The present study aims to explore genome size differences between some species of the H. azteca complex co-occurring in a Canadian boreal lake using flow cytometry. Nuclear DNA content was estimated for 50 individuals belonging to six COI haplotypes corresponding to four provisional species of the H. azteca complex. Species from the large ecomorph had C-values significantly larger than species from the small ecomorph, whereas slight differences were found among species of the small ecomorph. These differences in genome sizes might be linked to ecological and physiological differences among species of the H. azteca complex.

  8. Approaching invasive species in Madagascar | Kull | Madagascar ...

    African Journals Online (AJOL)

    invasive', the topic of invasive species has until recently received less attention here than in other island contexts. Some species, often alien to Madagascar and introduced by humans, have expanded their range rapidly and have had both ...

  9. Tetrameranthus (Annonaceae) revisited including a new species

    Science.gov (United States)

    Westra, Lubbert Y.T.; Maas, Paul J. M.

    2012-01-01

    Abstract The taxonomic revision of the infrequently collected genus Tetrameranthus by Westra (1985) is updated. A new species is described from French Guiana and Amapá, Brazil, increasing the number of species in this genus to seven. PMID:22645410

  10. Tetrameranthus (Annonaceae revisited including a new species

    Directory of Open Access Journals (Sweden)

    Lubbert Y.Th. Westra

    2012-04-01

    Full Text Available The taxonomic revision of the infrequently collected genus Tetrameranthus by Westra (1985 is updated. A new species is described from French Guiana and Amapá, Brazil, increasing the number of species in this genus to seven.

  11. Endangered species toxicity extrapolation using ICE models

    Science.gov (United States)

    The National Research Council’s (NRC) report on assessing pesticide risks to threatened and endangered species (T&E) included the recommendation of using interspecies correlation models (ICE) as an alternative to general safety factors for extrapolating across species. ...

  12. New species of Cystolepiota from China

    Directory of Open Access Journals (Sweden)

    Meng-Lin Xu

    2016-10-01

    Full Text Available In this paper, a new species, Cystolepiota pseudofumosifolia, is introduced. C. pseudofumosifolia is characterized by granulose or powdery pileus with an anatomic structure that is loosely globose, as well as ellipsoid cells in chains in the pileus covering the cheilocystidia. This new species is compared to the related and similar Cystolepiota species in morphology and molecular phylogeny based on Internal transcribed spacer sequences. Both types of data support our specimens as a new species in the genus Cystolepiota.

  13. Linking Keystone Species and Functional Groups: A New Operational Definition of the Keystone Species Concept

    Directory of Open Access Journals (Sweden)

    Robert D. Davic

    2003-07-01

    Full Text Available The concept of the "keystone species" is redefined to allow for the a priori prediction of these species within ecosystems. A keystone species is held to be a strongly interacting species whose top-down effect on species diversity and competition is large relative to its biomass dominance within a functional group. This operational definition links the community importance of keystone species to a specific ecosystem process, e.g., the regulation of species diversity, within functional groups at lower trophic levels that are structured by competition for a limited resource. The a priori prediction of keystone species has applied value for the conservation of natural areas.

  14. Unimodal models to relate species to environment

    NARCIS (Netherlands)

    Braak, ter C.J.F.

    1987-01-01

    To assess the impact of environmental change on biological communities knowledge about species-environment relationships is indispensable. Ecologists attempt to uncover the relationships between species and environment from data obtained from field surveys. In the survey, species are scored on their

  15. Invasive Species Science Update (No. 9)

    Science.gov (United States)

    Justin Runyon

    2017-01-01

    This newsletter is designed to keep managers and other users up-to-date with recently completed and ongoing research by RMRS scientists, as well as to highlight breaking news related to invasive species issues. The newsletter is produced by the RMRS Invasive Species Working Group (ISWG), a core group of scientists who volunteer to disseminate RMRS invasive species...

  16. Do invasive plant species alter soil health?

    Science.gov (United States)

    Invasive species may alter soil characteristics or interact with the soil microbial community to yield a competitive advantage. Our objectives were to determine: if invasive plant species alter soil properties important to soil health; and the long-term effects of invasive plant species on soil pro...

  17. 78 FR 70317 - Invasive Species Advisory Committee

    Science.gov (United States)

    2013-11-25

    ... DEPARTMENT OF THE INTERIOR Office of the Secretary Invasive Species Advisory Committee AGENCY..., notice is hereby given of meetings of the Invasive Species Advisory Committee. The purpose of the Advisory Committee is to provide advice to the National Invasive Species Council, as authorized by...

  18. 75 FR 69698 - Invasive Species Advisory Committee

    Science.gov (United States)

    2010-11-15

    ... DEPARTMENT OF THE INTERIOR Office of the Secretary Invasive Species Advisory Committee AGENCY: Office of the Secretary, Interior. ACTION: Notice of public meetings of the Invasive Species Advisory... of meetings of the Invasive Species Advisory Committee (ISAC). Comprised of 30 nonfederal invasive...

  19. Invasive Species Science Update (No. 4)

    Science.gov (United States)

    Ned B. Klopfenstein; Brian W. Geils

    2010-01-01

    The fourth issue of Invasive Species Science Update has finally arrived. This newsletter has no set publication schedule, but our intent is to deliver invasive species information on a timely basis. The RMRS Invasive Species Working Group (ISWG) has been reorganized and recharged. General information on the ISWG is presented in a publication by Butler and others (2009...

  20. Invasive Species Science Update (No. 7)

    Science.gov (United States)

    Dean Pearson; Yvette Ortega; Jack Butler

    2014-01-01

    Invasive Species Science Updates are designed to keep managers and other users up-to-date with recently completed and ongoing research by RMRS scientists, as well as highlight breaking news related to invasive species issues. The newsletter is produced by the RMRS Invasive Species Working Group (ISWG), which is a core group of scientists who volunteer to coordinate...

  1. Invasive Species Science Update (No. 5)

    Science.gov (United States)

    Dean Pearson; Yvette Ortega

    2011-01-01

    Welcome to the fifth issue of the Rocky Mountain Research Station's (RMRS) Invasive Species Science Update. The newsletter is produced by the RMRS Invasive Species Working Group (ISWG), which is a core group of scientists who volunteer to coordinate outreach of RMRS invasive species science to managers and the public. After publishing the past four newsletters, we...

  2. 78 FR 11899 - Invasive Species Advisory Committee

    Science.gov (United States)

    2013-02-20

    ... DEPARTMENT OF THE INTERIOR Office of the Secretary Invasive Species Advisory Committee AGENCY... notice of public meetings of the Invasive Species Advisory Committee. The document contained incorrect..., March 6, 2013; 9 a.m. to 1:45 p.m. Meeting of the Invasive Species Advisory Committee (OPEN): Thursday...

  3. 76 FR 68776 - Invasive Species Advisory Committee

    Science.gov (United States)

    2011-11-07

    ... DEPARTMENT OF THE INTERIOR Office of the Secretary Invasive Species Advisory Committee AGENCY: Office of the Secretary, Interior. ACTION: Notice of public meetings of the Invasive Species Advisory... of meetings of the Invasive Species Advisory Committee (ISAC). Comprised of 29 nonfederal invasive...

  4. Invasive Species Science Update (No. 8)

    Science.gov (United States)

    Dean Pearson; Yvette Ortega; Jack Butler

    2015-01-01

    Invasive Species Science Updates are designed to keep managers and other users up-to-date with recently completed and ongoing research by RMRS scientists, as well as highlight breaking news related to invasive species issues. The newsletter is produced by the RMRS Invasive Species Working Group (ISWG), which is a core group of scientists who volunteer to coordinate...

  5. 77 FR 23740 - Invasive Species Advisory Committee

    Science.gov (United States)

    2012-04-20

    ... DEPARTMENT OF THE INTERIOR Office of the Secretary Invasive Species Advisory Committee AGENCY: Office of the Secretary, Interior. ACTION: Notice of Public Meetings of the Invasive Species Advisory... of meetings of the Invasive Species Advisory Committee (ISAC). Comprised of 30 nonfederal invasive...

  6. What is a Species? An Endless Debate

    Indian Academy of Sciences (India)

    Permanent link: http://www.ias.ac.in/article/fulltext/reso/013/11/1049-1064. Keywords. Species; species concept; category; taxon; species problem. Author Affiliations. Uttam Saikia1 Narayan Sharma1 Abhijit Das1. High Altitude Zoology Field Station Zoological Survey of India Saproon, Solan H.P.173211, India. Resonance ...

  7. What is a Species? An Endless Debate

    Indian Academy of Sciences (India)

    Srimath

    guideline for delimiting species taxa. This approach, however, could not account for geographical variations among conspecif- ics (of the same species) as well as sympatric (cohabiting) groups, closely alike, but belonging to different species. Thus, apart from taxonomic utility, it did not have much biological value. In early.

  8. Aphid (Hemiptera: Aphididae) species determined on herbaceous ...

    African Journals Online (AJOL)

    This study aimed to find out the Aphidoidea species feeding on herbaceous and shrub plants of Bartýn province. As a result, total of 28 aphid species belonging to 14 genus and 4 tribes of the super family Aphidoidea were determined. Of these determined species, Aphis fabae Scopoli, Aphis farinosa J. F. Gmelin, Aphis ...

  9. Vegetation composition and structure influences bird species ...

    African Journals Online (AJOL)

    Two gradients of increasing vegetation structural heterogeneity were most important in influencing bird community composition and had positive effects on species diversity and the presence of most of the species assessed: (1) increasing closed cover due to woody plant density, which also had positive effects on species ...

  10. Brachyspira Species and Gastroenteritis in Humans

    NARCIS (Netherlands)

    Westerman, L J; de Boer, R F; Roelfsema, J H; Friesema, I H M; Kortbeek, L M; Wagenaar, J A; Bonten, M J M; Kusters, J G

    Brachyspira species have been implicated as a potential cause of gastroenteritis in humans; this is, however, controversial. In 733 gastroenteritis cases and 464 controls, we found 29 samples positive for Brachyspira species (2.3% of cases and 2.6% of controls; P = 0.77). Brachyspira species were

  11. Brachyspira Species and Gastroenteritis in Humans

    NARCIS (Netherlands)

    Westerman, L.J.; Boer, de R.F.; Roelfsema, J.H.; Friesema, I.H.M.; Kortbeek, L.M.; Wagenaar, J.A.; Bonten, M.J.M.; Kusters, J.G.

    2013-01-01

    Brachyspira species have been implicated as a potential cause of gastroenteritis in humans; this is, however, controversial. In 733 gastroenteritis cases and 464 controls, we found 29 samples positive for Brachyspira species (2.3% of cases and 2.6% of controls; P = 0.77). Brachyspira species were

  12. Isolation, Culture and Cryopreservation of Sarcocystis species

    Science.gov (United States)

    More than 200 valid Sarcocystis species have been described in the parasitological literature. The developmental life cycle in the intermediate host and definitive host has only been described for a few species. The majority of species have been identified based solely on the presence of the sarcocy...

  13. Options in dealing with marine alien species

    NARCIS (Netherlands)

    Pelt-Heerschap, van H.M.L.; Sneekes, A.C.; Foekema, E.M.

    2015-01-01

    Invasive species can have strong impact on the local ecosystem, not only substantial impact on the local ecosystem, but also on economy and human health. This review on marine alien species outlines aspects of prevention, eradication and control strategies. When managing invasive species, prevention

  14. Endangered Species & Biodiversity: A Classroom Project & Theme

    Science.gov (United States)

    Lauro, Brook

    2012-01-01

    Students discover the factors contributing to species losses worldwide by conducting a project about endangered species as a component of a larger classroom theme of biodiversity. Groups conduct research using online endangered- species databases and present results to the class using PowerPoint. Students will improve computer research abilities…

  15. 22 CFR 216.5 - Endangered species.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Endangered species. 216.5 Section 216.5 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ENVIRONMENTAL PROCEDURES § 216.5 Endangered species. It is A... endangered or threatened species and their critical habitats. The Initial Environmental Examination for each...

  16. 3 CFR - The Endangered Species Act

    Science.gov (United States)

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false The Endangered Species Act Presidential Documents Other Presidential Documents Memorandum of March 3, 2009 The Endangered Species Act Memorandum for the Heads of Executive Departments and Agencies The Endangered Species Act (ESA), 16 U.S.C. 1531 et seq...

  17. Demography of threatened tree species in Vietnam

    NARCIS (Netherlands)

    Chien, P.D.

    2006-01-01

    Demography of threatened tree species in Vietnam (Summary for the library) Effective conservation of threatened tree species requires information on natural dynamics and future prospects of populations of these species. Such information can be obtained from demographic studies. We investigated the

  18. Reactive species and pulmonary edema.

    Science.gov (United States)

    Iles, Karen E; Song, Weifeng; Miller, David W; Dickinson, Dale A; Matalon, Sadis

    2009-10-01

    Pulmonary edema occurs when fluid flux into the lung interstitium exceeds its removal, resulting in hypoxemia and even death. Noncardiogenic pulmonary edema (NPE) generally results when microvascular and alveolar permeability to plasma proteins increase, one possible etiology being oxidant injury. Reactive oxygen and nitrogen species (RONS) can modify or damage ion channels, such as epithelial sodium channels, which alters fluid balance. Experimental systems in which either RONS are increased or protective antioxidant mechanisms are decreased result in alterations of epithelial sodium channel activity and support the hypothesis that RONS are important in NPE. Both basic and clinical studies are needed to critically define the RONS-NPE connection and the capacity of antioxidant therapy (either alone or as a supplement to β-agonists) to improve patient outcome.

  19. Satellite tracking of threatened species

    Science.gov (United States)

    Williams, M.; Lunsford, A.; Ellis, D.; Robinson, J.; Coronado, P.; Campbell, W.

    1998-01-01

    In 1990, a joint effort of two U.S. federal agencies, NASA Goddard Space Flight Center (GSFC) and the Patuxent Wildlife Research Center, began. We initially joined forces in a project that used satellite telemetry to discover the winter home of a tiny dwindling population of Siberian Cranes. Since then several projects have emerged, and a web site was created to follow some of these activities. This web site is called the Satellite Tracking of Threatened Species and its location is http://sdcd.gsfc.nasa.gov/ISTO/satellite_tracking. It describes the overall program, and links you to three subsections that describe the projects in more detail: Satellite Direct Readout, Birdtracks, and Birdworld.

  20. New french uranium mineral species

    International Nuclear Information System (INIS)

    Branche, G.; Chervet, J.; Guillemin, C.

    1952-01-01

    In this work, the authors study the french new uranium minerals: parsonsite and renardite, hydrated phosphates of lead and uranium; kasolite: silicate hydrated of uranium and lead uranopilite: sulphate of uranium hydrated; bayleyite: carbonate of uranium and of hydrated magnesium; β uranolite: silicate of uranium and of calcium hydrated. For all these minerals, the authors give the crystallographic, optic characters, and the quantitative chemical analyses. On the other hand, the following species, very rare in the french lodgings, didn't permit to do quantitative analyses. These are: the lanthinite: hydrated uranate oxide; the α uranotile: silicate of uranium and of calcium hydrated; the bassetite: uranium phosphate and of hydrated iron; the hosphuranylite: hydrated uranium phosphate; the becquerelite: hydrated uranium oxide; the curite: oxide of uranium and lead hydrated. Finally, the authors present at the end of this survey a primary mineral: the brannerite, complex of uranium titanate. (author) [fr

  1. The nuclear question: rethinking species importance in multi-species animal groups.

    Science.gov (United States)

    Srinivasan, Umesh; Raza, Rashid Hasnain; Quader, Suhel

    2010-09-01

    1. Animals group for various benefits, and may form either simple single-species groups, or more complex multi-species associations. Multi-species groups are thought to provide anti-predator and foraging benefits to participant individuals. 2. Despite detailed studies on multi-species animal groups, the importance of species in group initiation and maintenance is still rated qualitatively as 'nuclear' (maintaining groups) or 'attendant' (species following nuclear species) based on species-specific traits. This overly simplifies and limits understanding of inherently complex associations, and is biologically unrealistic, because species roles in multi-species groups are: (i) likely to be context-specific and not simply a fixed species property, and (ii) much more variable than this dichotomy indicates. 3. We propose a new view of species importance (measured as number of inter-species associations), along a continuum from 'most nuclear' to 'least nuclear'. Using mixed-species bird flocks from a tropical rainforest in India as an example, we derive inter-species association measures from randomizations on bird species abundance data (which takes into account species 'availability') and data on 86 mixed-species flocks from two different flock types. Our results show that the number and average strength of inter-species associations covary positively, and we argue that species with many, strong associations are the most nuclear. 4. From our data, group size and foraging method are ecological and behavioural traits of species that best explain nuclearity in mixed-species bird flocks. Parallels have been observed in multi-species fish shoals, in which group size and foraging method, as well as diet, have been shown to correlate with nuclearity. Further, the context in which multi-species groups occur, in conjunction with species-specific traits, influences the role played by a species in a multi-species group, and this highlights the importance of extrinsic factors in

  2. Alien species on the coasts of Turkey

    Directory of Open Access Journals (Sweden)

    M.E. CINAR

    2005-12-01

    Full Text Available The compilation of data on alien species reported from the Turkish coasts yielded a total of 263 species belonging to 11 systematic groups, of which Mollusca had the highest number of species (85 species, followed by Crustacea (51, fishes (43 and phytobenthos (39. The Black Sea is represented by a total of 20 alien species, the Sea of Marmara by 48 species, the Aegean Sea by 98 species and the Levantine Sea by 202 species. The majority of aliens found in the Black Sea and the Sea of Marmara were transported via shipping, whereas the Levantine coast is extensively subjected to Lessepsian migration. Benthic habitats (soft and hard substrata comprise 76% of the total alien species and the pelagic environment is inhabited by thirty-nine species. Almost 50% of aliens collected from the Turkish coasts were found only at 0-10 m depth. Eight species occur at depths deeper than 100 m. The impacts of aliens on the benthic and pelagic ecosystems are presented.

  3. Metabolite production by differnt Ulocladium species

    DEFF Research Database (Denmark)

    Andersen, Birgitte; Hollensted, Morten

    2008-01-01

    Ulocladium, which is phylogenetically related to Alternaria, contains species that are food spoilers and plant pathogens, but also species that have potential as enzyme producers and bio-control agents. Ulocladium spp. are often found on dead vegetation, in soil, air and dust, but also on food...... metabolites was correlated to species identity and source of isolation (substratum). Chemical analyses corroborated the morphological identifications and showed the existence of several species species-specific metabolites, of which most were known Compounds. The production of curvularins was specific...... to Ulocladium atrum, while most species produced infectopyrones and derivatives of altertoxin I. None of the 52 Ulocladium strains produced alternariols, tenuazonic acid, altersolanols or macrosporin, which are common in species of Alternaria. (c) 2008 Elsevier B.V. All rights reserved...

  4. Genomic definition of species. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Crkvenjakov, R.; Dramanac, R.

    1992-06-01

    A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called (species) genome. The definition of species based on chromosomes, genes, or genome common to its member organisms has been implied or mentioned in passing numerous times. Some population biologists think that members of species have similar ``homeostatic genotypes,`` which are to a degree resistant to mutation or environmental change in the production of a basic phenotype.

  5. Genomic definition of species. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Crkvenjakov, R.; Drmanac, R.

    1993-03-01

    A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species- and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called species genome. Our proposal for the definition of a biological species is as follows: A species comprises a group of actual and potential biological organisms built according to a unique genome program that is recorded, and at least in part expressed, in the structures of their genomic nucleic acid molecule(s), having intragroup sequence differences which can be fully interconverted in the process of organismal reproduction.

  6. Sea Cucumber (Holothuroidea Species of Turkey

    Directory of Open Access Journals (Sweden)

    Mehmet AYDIN

    2016-11-01

    Full Text Available There are nearly 1200 sea cucumber species in the world oceans, while only 37 species from Holothuroidea class lives in the Mediterranean Sea. This preliminary study aims identification sea cucumbers species of the Turkish waters. The sea cucumber samples used in this study were obtained from a series of different studies between the years of 2008 and 2014. Identification of the species are mainly based on the morphometric characteristics while some of species are determined from their calcareous spicules. Eight sea species were identified in this research which are; Holothuria tubulosa, Holothuria polii, Holothuria mammata, Holothuria (Platyperona sanctori, Holothuria forskali, Stichopus regalis, Synaptula reciprocans and Stereoderma kirschbergi. There are limited number of studies in the literature focusing on the identification of the sea cucumber species spread in our seas. Therefore, this study is believed to play an important role in guiding future researches.

  7. Contributions to the study of the marine algae inhabiting Umluj Seashore, Red Sea

    Directory of Open Access Journals (Sweden)

    Ibraheem Borie Mohammad Ibraheem

    2014-12-01

    Full Text Available The marine algal flora of the Umluj city received no attention about the marine macroalgae. In this paper a total of 19 species are reported for the first time as occurring in the Umluj coast of Saudi Arabia. These species related to Chlorophyta (1, Phaeophyceae (6 and Rhodophyceae (12.

  8. Program SimAssem: software for simulating species assemblages and estimating species richness

    Science.gov (United States)

    Gordon C. Reese; Kenneth R. Wilson; Curtis H. Flather

    2013-01-01

    1. Species richness, the number of species in a defined area, is the most frequently used biodiversity measure. Despite its intuitive appeal and conceptual simplicity, species richness is often difficult to quantify, even in well surveyed areas, because of sampling limitations such as survey effort and species detection probability....

  9. Four new species of Pteromalus Swederus (Hymenoptera: Chalcidoidea: Pteromalidae) and redescriptions of three other species

    NARCIS (Netherlands)

    Gijswijt, M.J.

    1999-01-01

    A key to the European species of the Pteromalus altus group is presented. The relationship between this group and species of the genus Euphorbia (Euphorbiaceae) is confirmed. One new species: P. villosae, associated with Euphorbia villosa Waldst. & Kit.is presented. Two new species of the albipennis

  10. A globally-distributed alien invasive species poses risks to United States imperiled species.

    Science.gov (United States)

    McClure, Meredith L; Burdett, Christopher L; Farnsworth, Matthew L; Sweeney, Steven J; Miller, Ryan S

    2018-03-28

    In the midst of Earth's sixth mass extinction event, non-native species are a driving factor in many imperiled species' declines. One of the most widespread and destructive alien invasive species in the world, wild pigs (Sus scrofa) threaten native species through predation, habitat destruction, competition, and disease transmission. We show that wild pigs co-occur with up to 87.2% of imperiled species in the contiguous U.S. identified as susceptible to their direct impacts, and we project increases in both the number of species at risk and the geographic extent of risks by 2025. Wild pigs may therefore present a severe threat to U.S. imperiled species, with serious implications for management of at-risk species throughout wild pigs' global distribution. We offer guidance for efficient allocation of research effort and conservation resources across species and regions using a simple approach that can be applied to wild pigs and other alien invasive species globally.

  11. Malassezia species and seborrheic dermatitis.

    Science.gov (United States)

    Zisova, Lilia G

    2009-01-01

    Malassezia spp. are medically important dimorphic, lipophilic yeasts that form part of the normal cutaneous microflora of human. Seborrheic dermatitis is a multifactor disease that needs endogenous and exogenous predisposing factors for its development. Presence of these factors leads to reproduction of the saprophytic opportunistic pathogen Malassezia spp. and development of a disease. The inflammatory reaction against the yeast Malassezia is considered basic in the etiology of the seborrheic dermatitis. The pathogenesis and exact mechanisms via which these yeasts cause inflammation are still not fully elucidated. They are rather complex and subject of controversy in literature. Most probably Malassezia spp. cause seborrheic dermatitis by involving and combining both nonummune and immune mechanisms (nonspecific and specific). Which of these mechanisms will dominate in any single case depends on the number and virulence of the yeasts as well as on the microorganism reactivity. In the recent years a great interest have been aroused by the epidemiological investigations. Depending on the geographical place of the countries different Malassezia species in seborrheic dermatitis dominate in the different countries. In view of the etiology and pathogenesis of the seborrheic dermatitis comprehensive antifungal preparations have been recently introduced and are nowadays the basic therapeutic resource in the treatment of this disease.

  12. [Pharmacognosy study of Verbascum species].

    Science.gov (United States)

    Török, Tamás; Varga, Erzsébet

    2015-01-01

    The mullein (Verbascum phlomoides L., V thapsus L., V. thapsiforme Schrad., V. speciosum L.) is a medicinal herb known and used for a long time, especially in traditional Turkish medicine. The aims of our study were to identify the species and study the plant's major active substances both qualitatively and quantitatively, comparing it to data found in scientific literature. The plants were identified as probable hybrids of V. phlomoides and V. thapsiforme. Microscopic analysis of the flowers showed no major difference between the specimens. The diameter of both stomata and pollen we observed was around 15-20 μm. Important flavonoids like rutin and quercetin were identified. Dosage resulted in a 0.135% total flavonoid aglycone content. (expressed as hypericin) and a 1.3% total flavonoid glycoside content (expressed as rutoside). Thin layer chromatography from saponines revealed two spots. A hemolytic index of 13095 was also determined. Repeating the dosage experiment a year later resulted in significantly lower flavonoid aglycone and glycoside content (0.006% and 0.95% respectively) as well as a hemolytic index of approximately 4000.

  13. Ribonuclease Production by Aspergillus species

    Directory of Open Access Journals (Sweden)

    Gomes Eleni

    1998-01-01

    Full Text Available Ribonuclease production by Aspergillus flavipes, A. sulphureus and A. fischeri in semi-synthetic medium, after 24-144 hours at 30ºC under shaking, was studied. After cultivation, the medium was separated from micelia by filtration and the resultant solution was used as enzymatic extract. The highest amount of biomass and RNase was obtained after 96 hours of cultivation. The enzymes produced by three species presented similar characteristics, with optimum temperature at 55ºC and two peaks of activity at pH 4.5 and 7.0. A. flavipes RNases were more sensitive to temperature: 50% of the initial activity was lost after 1 hour at 70ºC. After this heat treatment, RNase of A. sulphureus lost 30% of this activity and that of A. fischeri only 16%. The nucleotides released by enzimatic hydrolysis of RNA were separated by ion exchange chromatography in a AG-1X8-formiate column and identified by paper chromatography. This procedure indicated that the raw enzymatic extract of Aspergillus flavipes is able to hydrolyze RNA, releasing 3'-nucleotides monophosphate at pH 4.5 and 3' and 5'-nucleotides monophosphate at pH 7.0 and 8.5. This result suggests that this strain produces two different types of RNase, one acidic and other alcaline, with different specificities.

  14. The myth of plant species saturation

    Science.gov (United States)

    Stohlgren, Thomas J.; Barnett, David T.; Jarnevich, Catherine S.; Flather, Curtis; Kartesz, John

    2008-01-01

    Plant species assemblages, communities or regional floras might be termed ‘saturated’ when additional immigrant species are unsuccessful at establishing due to competitive exclusion or other inter-specific interactions, or when the immigration of species is off-set by extirpation of species. This is clearly not the case for state, regional or national floras in the USA where colonization (i.e. invasion by exotic species) exceeds extirpation by roughly a 24 to 1 margin. We report an alarming temporal trend in plant invasions in the Pacific Northwest over the past 100 years whereby counties highest in native species richness appear increasingly invaded over time. Despite the possibility of some increased awareness and reporting of native and exotic plant species in recent decades, historical records show a significant, consistent long-term increase in exotic species (number and frequency) at county, state and regional scales in the Pacific Northwest. Here, as in other regions of the country, colonization rates by exotic species are high and extirpation rates are negligible. The rates of species accumulation in space in multi-scale vegetation plots may provide some clues to the mechanisms of the invasion process from local to national scales.

  15. Species longevity in North American fossil mammals.

    Science.gov (United States)

    Prothero, Donald R

    2014-08-01

    Species longevity in the fossil record is related to many paleoecological variables and is important to macroevolutionary studies, yet there are very few reliable data on average species durations in Cenozoic fossil mammals. Many of the online databases (such as the Paleobiology Database) use only genera of North American Cenozoic mammals and there are severe problems because key groups (e.g. camels, oreodonts, pronghorns and proboscideans) have no reliable updated taxonomy, with many invalid genera and species and/or many undescribed genera and species. Most of the published datasets yield species duration estimates of approximately 2.3-4.3 Myr for larger mammals, with small mammals tending to have shorter species durations. My own compilation of all the valid species durations in families with updated taxonomy (39 families, containing 431 genera and 998 species, averaging 2.3 species per genus) yields a mean duration of 3.21 Myr for larger mammals. This breaks down to 4.10-4.39 Myr for artiodactyls, 3.14-3.31 Myr for perissodactyls and 2.63-2.95 Myr for carnivorous mammals (carnivorans plus creodonts). These averages are based on a much larger, more robust dataset than most previous estimates, so they should be more reliable for any studies that need species longevity to be accurately estimated. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  16. A new species of Calogalesus Kieffer from China (Hymenoptera, Diapriidae with a key to World species

    Directory of Open Access Journals (Sweden)

    Jun Feng

    2016-10-01

    Full Text Available A new species of Calogalesus Kieffer, 1912, C. sinicus sp. n., is described and illustrated, collected from a Chinese prickly ash (Zanthoxylum bungeanum Maxim. orchard in Yunnan province of China. This is the third described species of the genus in the World. The new species can be distinguished from the other two described Calogalesus species by the head profile, proportions of the antennal segments, tridentate mandible, and mandible length. A key to World species of the genus is provided.

  17. Radiation protection of non-human species

    International Nuclear Information System (INIS)

    Leith, I.S.

    1993-01-01

    The effects of radiation on non-human species, both animals and plants, have long been investigated. In the disposal of radioactive wastes, the protection of non-human species has been investigated. Yet no radiation protection standard for exposure of animals and plants per se has been agreed. The International Commission on Radiological Protection has long taken the view that, if human beings are properly protected from radiation, other species will thereby be protected to the extent necessary for their preservation. However, the International Atomic Energy Agency has found it necessary to investigate the protection of non-human species where radioactivity is released to an environment unpopulated by human beings. It is proposed that the basis of such protection, and the knowledge of radiation effects on non-human species on which it is based, suggest a practical radiation protection standard for non-human species. (1 tab.)

  18. Choosing the right species in research.

    Science.gov (United States)

    Mann, Michael D

    2015-07-01

    When designing animal studies, investigators must choose a species that is appropriate for the research. In this paper, the author examines various criteria that can be used to guide this selection. He discusses the concepts of phylogenetic group and sentience and finds them not to be useful in the selection of appropriate species in biomedical research. He identifies other criteria that are more useful as justifications for species selection, including susceptibility to a targeted disease process, tendency to engage in a targeted behavior, suitable size for the experimental techniques to be used, presence of a large body of data relevant to the study, species specificity (the species itself is the target of the research), intergenerational interval, similarity to humans, contractual specification and existing guidelines. He proposes that investigators should use these justifications, and perhaps others, to choose the most scientifically appropriate species for animal studies.

  19. Metabolite production by species of Stemphylium.

    Science.gov (United States)

    Olsen, Kresten Jon Kromphardt; Rossman, Amy; Andersen, Birgitte

    Morphology and phylogeny have been used to distinguish members of the plant pathogenic fungal genus Stemphylium. A third method for distinguishing species of fungi is by chemotaxonomy. The main goal of the present study was to investigate the chemical potential of Stemphylium via HPLC-UV-MS analysis, while also exploring the potential of chemotaxonomy as a robust identification method for Stemphylium. Several species were found to have species-specific metabolites, while other species were distinguishable by a broader metabolic profile rather than specific metabolites. Many previously described metabolites were found to be important for distinguishing species, while some unknown metabolites were also determined to have important roles in distinguishing species of Stemphylium. This study is the first of its kind to investigate the chemical potential of Stemphylium across the whole genus. Copyright © 2018 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  20. Two new Orchidantha species (Lowiaceae) from Borneo

    OpenAIRE

    Poulsen, A.D.; Leong-Škorničková, J.

    2017-01-01

    Two new Orchidantha species discovered in Sarawak, O. micrantha and O. megalantha, are described and illustrated. They may well represent the species with the smallest and the largest flowers currently known in the genus and certainly from Borneo. With its small flowers, O. micrantha is similar to O. borneensis to which it is compared. The large-flowered O. megalantha is compared to the morphologically closest species, O. holttumii, from nearby Brunei. The conservation status of both new spec...

  1. Diversity of Lophodermium species on pines

    OpenAIRE

    Lazarev Vladimir S.

    2004-01-01

    Multiannual study of needle-cast disease on pines shows that Lophodermium species, as well as other widely-ranging micro-organism species, are characterized by high variability in morphology, physiology, biology pathogenic characters, epiphytotiology and other characteristics, which points to the assumption on the existence of biotypes, forms or still unidentified species in this genus. This paper presents the study results which contribute to the elucidation of the confusion regarding the ge...

  2. Cadmium determination in Lentinus edodes mushroom species

    OpenAIRE

    Vera Akiko Maihara; Patricia Landim da Costa Moura; Marília Gabriela Miranda Catharino; Edson Gonçalves Moreira; Lilian Pavanelli Castro; Rubens Cesar Lopes Figueira

    2012-01-01

    Many studies have drawn attention to the occurrence and concentration of toxic elements found in the fruiting body of mushrooms. Some edible mushroom species are known to accumulate high levels of inorganic contaminants, mainly cadmium, mercury, and lead. There are about 2,000 known edible mushroom species, but only 25 of them are cultivated and used as food. In Brazil, the most marketed and consumed mushroom species are Agaricus bisporus, known as Paris champignon, Lentinus edodes, or Shitak...

  3. Economics of the Endangered Species Act

    OpenAIRE

    Gardner M. Brown; Jason F. Shogren

    1998-01-01

    The Endangered Species Act of 1973 is one of our most far-reaching and controversial environmental laws. While the benefits of protecting endangered species accrue to the entire nation, a significant fraction of the costs are borne by the private landowners who shelter about 90 percent of the nearly 1,000 listed species. The pressure to know whether the social benefits of preservation exceed the private costs has thrust economics into ongoing reauthorization debate. This paper examines how ec...

  4. Species coexistence in a changing world

    OpenAIRE

    Fernando eValladares; Fernando eValladares; Cristina C. Bastias; Oscar eGodoy; Elena eGranda; Elena eGranda; Adrian eEscudero

    2015-01-01

    The consequences of global change for the maintenance of species diversity will depend on the sum of each species responses to the environment and on the interactions among them. A wide ecological literature supports that these species-specific responses can arise from factors related to life strategies, evolutionary history and intraspecific variation, and also from environmental variation in space and time. In the light of recent advances from coexistence theory combined with mechanistic ex...

  5. Alien species alert: Crassostrea gigas (Pacific oyster)

    OpenAIRE

    Miossec, Laurence; Le Deuff, Rose-marie; Goulletquer, Philippe

    2009-01-01

    The Pacific oyster (Crassostrea gigas, Thunberg, 1793) is one of 20 species in the genus Crassostrea. Although native to the Japan/Korea region, C. gigas is a hardy species that has been introduced to a number of countries worldwide, including the US, Canada, the UK, France, Korea, China, New Zealand, Australia, South Africa, and South America, mainly for aquaculture purposes (Mann et al., 1991; Orensanz et al., 2002). As a result, C. gigas has become the leading species in world shellfish cu...

  6. Design and construction of "synthetic species".

    OpenAIRE

    Moreno Eduardo

    2012-01-01

    Synthetic biology is an area of biological research that combines science and engineering. Here, I merge the principles of synthetic biology and regulatory evolution to create a new species with a minimal set of known elements. Using preexisting transgenes and recessive mutations of Drosophila melanogaster, a transgenic population arises with small eyes and a different venation pattern that fulfils the criteria of a new species according to Mayr’s Biological Species Concept. The population de...

  7. Rapid algal toxicity assay using variable chlorophyll fluorescence for Chlorella kessleri (Chlorophyta)

    Czech Academy of Sciences Publication Activity Database

    Kvíderová, Jana

    2010-01-01

    Roč. 25, č. 6 (2010), s. 554-562 ISSN 1520-4081 R&D Projects: GA MŠk 1M0571 Institutional research plan: CEZ:AV0Z60050516 Keywords : bioassay * variable chlorophyll fluorescence * Chlorella kessleri Subject RIV: EF - Botanics Impact factor: 1.932, year: 2010

  8. Blue- and red-light regulation of the cell cycle in Chlamydomonas reinhardtii (Chlorophyta)

    Czech Academy of Sciences Publication Activity Database

    Oldenhof, H.; Zachleder, Vilém; van den Ende, H.

    2006-01-01

    Roč. 41, č. 3 (2006), s. 313-320 ISSN 0967-0262 R&D Projects: GA AV ČR(CZ) KJB5020305 Institutional research plan: CEZ:AV0Z50200510 Keywords : blue light * cell cycle * cell division Subject RIV: EE - Microbiology, Virology Impact factor: 1.293, year: 2006

  9. Confocal microscopy of chloroplast morphology and ontogeny in three strains of Dictyochloropsis (Trebouxiophyceae, Chlorophyta)

    Czech Academy of Sciences Publication Activity Database

    Škaloud, P.; Neustupa, J.; Radochová, Barbora; Kubínová, Lucie

    2005-01-01

    Roč. 44, č. 3 (2005), s. 261-269 ISSN 0031-8884 Grant - others:FRVŠ(CZ) 2826/2003; IGA MŠk(CZ) 139/2002/B Institutional research plan: CEZ:AV0Z5011922 Keywords : chloroplast ontogeny * confocal microscopy * Dichtyochloropsis Subject RIV: EF - Botanics Impact factor: 1.271, year: 2005

  10. 31P-NMR differentiation between intracellular phosphate pools in Cosmarium (chlorophyta)

    International Nuclear Information System (INIS)

    Elgavish, A.; Elgavish, G.A.

    1980-01-01

    31 P nuclear magnetic resonance (NMR) spectroscopy of intact Cosmarium sp. cells is presented as a suitable tool for the differentiation of intracellular accumulation pools of polyphosphates. The cold trichloroacetic acid (TCA) insoluble fraction is shown to contain most of the total cellular phosphate in the phosphate rich Cosmarium cells. Moreover, evidence from a 31 P-NMR study and electron microscopic observations of cold TCA treated Cosmarium cells indicate that this fraction consists mostly of polyphosphates which seem to retain the native morphological structure observed in the untreated cells. The determination of orthophosphate in the hot water extract of Cosmarium cells did not measure the polyphosphate pools. Determination of total phosphorus content in the hot water extract rendered a value three times higher than the frequently used orthophosphate determination procedure. However, as revealed by the 31 P-NMR spectra and the chemical analyses of the extract and of the treated cells, even total phosphorus in the extract measured only 30% of the total cellular phosphorus. 31 P-NMR enabled the unequivocal chemical identification of the major phosphate compounds in the hot water extract (Surplus P) as orthophosphate and polyphosphates of about 10 phosphate units chainlength. More than 70% of the accumulation pool of polyphosphates was still in the cells after extraction. However, the electron microscopy study revealed that the native granular structure of polyphosphates had been destroyed by the hot water extraction procedure

  11. Effect of Nutrient Starvation under High Irradiance on Lipid and Starch Accumulation in Chlorella fusca (Chlorophyta)

    Czech Academy of Sciences Publication Activity Database

    Jerez, C.G.; Malapascua, José R.; Sergejevová, Magda; Figueroa, Felix L.; Masojídek, Jiří

    2016-01-01

    Roč. 18, č. 1 (2016), s. 24-36 ISSN 1436-2228 R&D Projects: GA MŠk ED2.1.00/03.0110; GA MŠk EE2.3.30.0059; GA MŠk(CZ) EE2.3.20.0203 Institutional support: RVO:61388971 Keywords : Microalgae * Chlorella * Lipid Subject RIV: EE - Microbiology, Virology Impact factor: 2.748, year: 2016

  12. Enhanced Antitumoral Activity of Extracts Derived from Cultured Udotea flabellum (Chlorophyta

    Directory of Open Access Journals (Sweden)

    Rosa Moo-Puc

    2011-01-01

    Full Text Available Very few studies have been performed to evaluate the effect of culture conditions on the production or activity of active metabolites in algae. Previous studies suggest that the synthesis of bioactive compounds is strongly influenced by irradiance level. To investigate whether the antiproliferative activity of Udotea flabellum extracts is modified after cultivation, this green alga was cultured under four photon flux densities (PFD for 30 days. After 10, 20, and 30 days, algae were extracted with dichloromethane: methanol and screened for antiproliferative activity against four human cancer cell lines (laryngeal—Hep-2, cervix—HeLa, cervix squamous—SiHa and nasopharynx—KB by SRB assay. Lipid and phenol content were evaluated by standardized methods on algae organic extracts. After 10 days of cultivation, organic U. flabellum extracts showed a significant increase in antiproliferative activity on Hela and SiHa cells when compared to noncultured algae extracts. Extracts obtained after 10 and 20 days of culture were active on KB and Hep-2 cells. Total phenol and polyunsaturated fatty acid content in organic extracts changed with cultivation time but not by irradiance treatment. Extracts from U. flabellum obtained after 10 and 20 days of culture have been selected for fractionation and isolation of active compounds.

  13. The Xanthophyll Cycle in Green Algae (Chlorophyta): Its Role in the Phptosynthetic Apparatus

    Czech Academy of Sciences Publication Activity Database

    Masojídek, Jiří; Kopecký, Jiří; Koblížek, Michal; Torzillo, G.

    2004-01-01

    Roč. 6, - (2004), s. 342-349 ISSN 1435-8603 R&D Projects: GA MŠk LN00A141 Keywords : microlgae * fluorescence * non-photochemical Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.582, year: 2004

  14. BIOGEOGRAPHY OF CLADOPHOROPSIS-MEMBRANACEA (SIPHONOCLADALES, CHLOROPHYTA) AS REVEALED BY SINGLE COPY DNA DISTANCES

    NARCIS (Netherlands)

    KOOISTRA, WHCF; BOELEBOS, SA; STAM, WT; VANDENHOEK, C

    Single copy DNA measurements were determined among isolates of Cladophoropsis membranacea from the Caribbean, Mauritania, the Canary Islands and the Red Sea using DNA-DNA hybridization. The genotypic relationships found amongst the Atlantic isolates demonstrate that the present day distribution

  15. Microfossils With Suggested Affinities To The Pyramimonadales (Pyramimonadophyceae, Chlorophyta From The Lower Devonian Rhynie Chert

    Directory of Open Access Journals (Sweden)

    Kustatscher Evelyn

    2014-12-01

    Full Text Available An assemblage of unusual microfossils occurs within an accumulation of plant debris, hyphae, and various types of propagules in the Early Devonian Rhynie chert. Specimens consist of a vesicle with one or more prominent wings (alae arising from the surface; one wing forms a rim around the equator of the vesicle. The microfossils are interpreted as phycomata of a prasinophycean green alga based on morphological similarities to Pterospermella, a microfossil similar to phycoma stages of the extant Pterosperma (Pyramimonadales. This report represents the third record of phycomata in the Rhynie chert, suggesting that this Early Devonian ecosystem served as habitat to a variety of prasinophyte algae. Moreover, the new microfossils add to the inventory of fossil freshwater representatives of this predominantly marine group of algae.

  16. Cladophora (Chlorophyta) spp. harbor human bacterial pathogens in nearshore water of Lake Michigan

    Science.gov (United States)

    Ishii, S.; Yan, T.; Shively, D.A.; Byappanahalli, M.N.; Whitman, R.L.; Sadowsky, M.J.

    2006-01-01

    Cladophora glomerata, a macrophytic green alga, is commonly found in the Great Lakes, and significant accumulations occur along shorelines during the summer months. Recently, Cladophora has been shown to harbor high densities of the fecal indicator bacteria Escherichia coli and enterococci. Cladophora may also harbor human pathogens; however, until now, no studies to address this question have been performed. In the present study, we determined whether attachedCladophora, obtained from the Lake Michigan and Burns Ditch (Little Calumet River, Indiana) sides of a breakwater during the summers of 2004 and 2005, harbored the bacterial pathogens Shiga toxin-producing Escherichia coli (STEC),Salmonella, Shigella, and Campylobacter. The presence of potential pathogens and numbers of organisms were determined by using cultural methods and by using conventional PCR, most-probable-number PCR (MPN-PCR), and quantitative PCR (QPCR) performed with genus- and toxin-specific primers and probes. WhileShigella and STEC were detected in 100% and 25%, respectively, of the algal samples obtained near Burns Ditch in 2004, the same pathogens were not detected in samples collected in 2005. MPN-PCR and QPCR allowed enumeration of Salmonella in 40 to 80% of the ditch- and lakeside samples, respectively, and the densities were up to 1.6 × 103 cells per g Cladophora. Similarly, these PCR methods allowed enumeration of up to 5.4 × 102 Campylobacter cells/gCladophora in 60 to 100% of lake- and ditchside samples. The Campylobacterdensities were significantly higher (P pathogenic bacteria in Lake Michigan and that the association of these bacteria with Cladophora warrants additional studies to assess the potential health impact on beach users.

  17. Life without a cell membrane: Challenging the specificity of bacterial endophytes within Bryopsis (Bryopsidales, Chlorophyta

    Directory of Open Access Journals (Sweden)

    Hollants Joke

    2011-11-01

    Full Text Available Abstract Background The siphonous green macroalga Bryopsis has some remarkable characteristics. Besides hosting a rich endophytic bacterial flora, Bryopsis also displays extraordinary wound repair and propagation mechanisms. This latter feature includes the formation of protoplasts which can survive in the absence of a cell membrane for several minutes before regenerating into new individuals. This transient 'life without a membrane' state, however, challenges the specificity of the endophytic bacterial communities present and raises the question whether these bacteria are generalists, which are repeatedly acquired from the environment, or if there is some specificity towards the Bryopsis host. Results To answer this question, we examined the temporal stability and the uniqueness of endobiotic bacterial communities within Bryopsis samples from the Mexican west coast after prolonged cultivation. DGGE analysis revealed that Bryopsis endophytic bacterial communities are rather stable and clearly distinct from the epiphytic and surrounding cultivation water bacterial communities. Although these endogenous communities consist of both facultative and obligate bacteria, results suggest that Bryopsis owns some intrinsic mechanisms to selectively maintain and/or attract specific bacteria after repeated wounding events in culture. Conclusions This suggests that Bryopsis algae seem to master transient stages of life without a cell membrane well as they harbor specific - and possibly ecological significant - endophytic bacteria.

  18. BIOGEOGRAPHY OF CLADOPHOROPSIS-MEMBRANACEA (CHLOROPHYTA) BASED ON COMPARISONS OF NUCLEAR RDNA ITS SEQUENCES

    NARCIS (Netherlands)

    KOOISTRA, WHCF; STAM, WT; OLSEN, JL; VANDENHOEK, C

    1992-01-01

    Nucleotides were compared at 988 sites, spanning both internal transcribed spacers (ITS1 and ITS2) of the nuclear ribosomal DNA, among 17 isolates of the green alga Cladophoropsis membranacea (Hofman Bang ex C. Agardh) Boergesen and two isolates of Struvea anastomosans (Harvey) Piccone and Grunow.

  19. Genetic polymorphism in eight Chilean strains of the carotenogenic microalga Dunaliella salina Teodoresco (Chlorophyta

    Directory of Open Access Journals (Sweden)

    PATRICIA I GOMEZ

    2001-01-01

    Full Text Available Eight Chilean strains of Dunaliella salina obtained within a restricted geographic range, but exhibiting a high variability in their morphology, rate of growth and carotenogenic capacity, were analyzed by Random Amplified Polymorphic DNA (RAPD-PCR. Twenty of the 50 random primers (D, P, OPA and OPD series that were tested amplified reproducible bands and were useful for comparative analysis of the strains. Of 107 polymorphic genetic markers, 49 were strain-specific. A great genetic variability was found among the strains in spite of their geographic proximity. In addition, phenetic analysis of the data showed close agreement between the morpho-physiological attributes and the genetic diversity of the strains

  20. Variability in the ecophysiology of Halimeda spp. (Chlorophyta, Bryopsidales) on Conch Reef, Florida Keys, USA

    NARCIS (Netherlands)

    Beach, K; Walters, L; Vroom, P; Coyer, J; Hunter, C

    The photosynthetic performance, pigmentation, and growth of a Halimeda community were studied over a depth gradient on Conch Reef, Florida Keys, USA during summer-fall periods of 5 consecutive years. The physiology and growth of H. tuna (Ellis & Solander) Lamouroux and H. opuntia (L.) Lamouroux on

  1. Checklist and Bibliography of Benthic Marine Macroalgae Recorded from Northern Australia. III. Chlorophyta,

    Science.gov (United States)

    1987-05-01

    polynesischen Formen dieser Famille." Beh. bot. Zbl., 18, 165-193, pls 5,6. Chapman, v.J. (1977). "Marine algae of Norfolk Island and Cook Island." Botanica ... botanica altera. Sistens generwn plantarum. Suppl. 3, Vienna, 111 pp. 7E;bank, L. (1946). "Hawaiian representatives of the genus Caulerpa. - Univ...vicinity of Townsville, Queensland." Atoll Res. Bull., 237, 1-29. Nizamuddin, m. (1967). "Caulerpa from Karachi Coast. II." Botanica rnar., 10, 158-166

  2. FRESH-WATER GREEN ALGAE (CHLOROPHYTA AS A NATURAL PIGMENT FOR MOJOSARI DUCKS

    Directory of Open Access Journals (Sweden)

    B. Indarsih

    2015-09-01

    Full Text Available An experiment in a completely randomize design was undertaken to study the use of fresh-watergreen algae as a yolk coloring agent in Mojosari ducks during a laying period on productiveperformance and egg quality from 36 to 44 wk of age. A total of 80 thirty-six wk–old laying ducks weredivided into four dietary treatments and each of four replicates with 5 birds. Diets were formulated witha commercial concentrate, rice bran and yellow corn (2:4:4 according to a commercial standard diet asa control, and three other dietary treatments with 2, 4 or 8% of green algae were included. Fresh watergreen algae had a significant effect on the feed uptake, egg production, and feed conversion ratio (FCR(p<0.05. Egg production and FCR improved at added 2 and 4% green algae. No differences wereobserved in egg yolk index, albumen index, Haugh Unit, and egg shell thickness (P>0.05 except eggyolk color. The yolk color increased within 7 days after feeding with the test diets. The present studyindicated that fresh-water green algae could be used as a natural coloring agent in laying ducks and at8% of green algae showed the highest score of (Roche Yellow Color-15.

  3. Hylodesmus singaporensis gen. et sp nov., a new autosporic subaerial green alga (Scenedesmaceae, Chlorophyta) from Singapore

    Czech Academy of Sciences Publication Activity Database

    Eliáš, M.; Němcová, Y.; Škaloud, P.; Neustupa, J.; Kaufnerová, V.; Šejnohová, Lenka

    2010-01-01

    Roč. 60, č. 5 (2010), s. 1224-1235 ISSN 1466-5026 R&D Projects: GA ČR GA206/06/0998 Institutional research plan: CEZ:AV0Z60050516 Keywords : phylogenetic tree selection * subunit ribosomal-RNA * taxonomy Subject RIV: EF - Botanics Impact factor: 1.930, year: 2010

  4. Lipidomic analysis of two closely related strains of the microalga Parietochloris (Trebouxiophyceae, Chlorophyta)

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Nedbalová, Linda; Lukavský, Jaromír; Procházková, L.; Sigler, Karel

    2017-01-01

    Roč. 25, JUL 2017 (2017), s. 473-482 ISSN 2211-9264 R&D Projects: GA ČR(CZ) GA17-00027S Institutional support: RVO:61388971 ; RVO:67985939 Keywords : Parietochloris * Arachidonic acid * Lipidomics Subject RIV: EE - Microbiology, Virology; EI - Biotechnology ; Bionics (BU-J) OBOR OECD: Microbiology; Bioproducts (products that are manufactured using biological material as feedstock) biomaterials, bioplastics, biofuels, bioderived bulk and fine chemicals, bio-derived novel materials (BU-J) Impact factor: 3.994, year: 2016

  5. Morphological and ultrastructural studies on Ulva flexuosa subsp. pilifera (Chlorophyta from Poland

    Directory of Open Access Journals (Sweden)

    Beata Messyasz

    2013-06-01

    Full Text Available Ulva flexuosa subsp. pilifera (Kütz. M. J. Wynne 2005 (= Enteromorpha pilifera Kützing 1845 was previously found in Argentina, the Czech Republic, Germany, Hungary, Romania, Slovakia and Sweden, recently also in Poland. The genus Ulva was first time described as Enteromorpha. Interestingly, Enteromorpha is used nowadays as a synonym for Ulva, a development which is based on molecular data. The morphologies of both young and mature specimens were studied, and most life cycle stages could be observed. Further, the formation of calcium carbonate crystals on the surface of Ulva thalli seems to influence the arrangement of the cells. A detailed ultrastructural (TEM analysis of cell walls is presented. The TEM reveals in great details highly complex, irregular structures with stratification lines.

  6. Phenotypic plasticity of wall ultrastructure in the green alga Pediastrum s.l. (Chlorophyta, Sphaeropleales

    Directory of Open Access Journals (Sweden)

    Lenarczyk Joanna

    2016-07-01

    Full Text Available This study examined wall ultrastructure variability in the microscopic green alga Pediastrum s.l. Its value as a diagnostic character is discussed. Field and cultured material of 21 taxa were compared using light and scanning electron microscopy. Nine ultrastructural elements occurring on the surface of Pediastrum are documented with LM and SEM micrographs. The highest number of taxa showed reticulate ornamentation composed of a trigonal mesh and granules situated on its corners. The paper considers the use of wall ultrastructure to reconcile traditional and modern taxonomical systems with regard to Pediastrum varieties, and addresses the phylogenetic relationships between strains representing different varieties.

  7. Exploring bacteria-induced growth and morphogenesis in the green macroalga order Ulvales (Chlorophyta

    Directory of Open Access Journals (Sweden)

    Thomas eWichard

    2015-03-01

    Full Text Available Green macroalgae, such as Ulvales, lose their typical morphology completely when grown under axenic conditions or in the absence of the appropriate microbiome. As a result, slow growing aberrant phenotypes or even callus-like morphotypes are observed in Ulvales. The cross-kingdom interactions between marine algae and microorganisms are hence not only restricted by the exchange of macronutrients, including vitamins and nutrients, but also by infochemicals such as bacterial morphogenetic compounds. The latter are a fundamental trait mediating the mutualism within the chemosphere where the organisms interact with each other via compounds in their surroundings.Approximately 60 years ago, pilot studies demonstrated that certain bacteria promote growth, whereas other bacteria induce morphogenesis; this is particularly true for the order of Ulvales. However, only slow progress was made towards the underlying mechanism due to the complexity of, for example, algal cultivation techniques, and the lack of standardized experiments in the laboratory.A breakthrough in this research was the discovery of the morphogenetic compound thallusin, which was isolated from an epiphytic bacterium and induces normal germination and restores the foliaceous morphotypes of Monostroma. Owing to the low concentration, the purification and structure elucidation of highly biologically active morphogenetic compounds is still challenging. Recently, it was found that only the combination of two specific bacteria from the Rhodobacteraceae and Flavobacteriaceae can completely recover the growth and morphogenesis of axenic Ulva mutabilis cultures forming a symbiotic tripartite community by chemical communication.This review combines literature detailing evidence of bacteria-induced morphogenesis in Ulvales. A set of standardized experimental approaches is further proposed for the preparation of axenic algal tissues, bacteria isolation, co-cultivation experiments, and the analysis of the chemosphere.

  8. New morphological features of the members of genus Stichococcus Nдgeli (Trebouxiophyceae, Chlorophyta

    Directory of Open Access Journals (Sweden)

    Victoria M. Karbovska

    2012-03-01

    Full Text Available The results of study of 31 strains of green algae from ACKU collection represented by original isolates as well as by subcultures deposited in international collections of strains of the genus Stichococcus Nägeli are reported. In 19 strains previously undescribed mucous structures have been founded, viz colonial mucilage, mucous sheath, mucous grains and mucous caps whose presence are inconsistent with the author’s diagnosis of this genus and confirms the assumption of phylogenetic heterogeneity of this genus at the phenotypic level.

  9. Exploring bacteria-induced growth and morphogenesis in the green macroalga order Ulvales (Chlorophyta)

    Science.gov (United States)

    Wichard, Thomas

    2015-01-01

    Green macroalgae, such as Ulvales, lose their typical morphology completely when grown under axenic conditions or in the absence of the appropriate microbiome. As a result, slow growing aberrant phenotypes or even callus-like morphotypes are observed in Ulvales. The cross-kingdom interactions between marine algae and microorganisms are hence not only restricted by the exchange of macronutrients, including vitamins and nutrients, but also by infochemicals such as bacterial morphogenetic compounds. The latter are a fundamental trait mediating the mutualism within the chemosphere where the organisms interact with each other via compounds in their surroundings. Approximately 60 years ago, pilot studies demonstrated that certain bacteria promote growth, whereas other bacteria induce morphogenesis; this is particularly true for the order of Ulvales. However, only slow progress was made towards the underlying mechanism due to the complexity of, for example, algal cultivation techniques, and the lack of standardized experiments in the laboratory. A breakthrough in this research was the discovery of the morphogenetic compound thallusin, which was isolated from an epiphytic bacterium and induces normal germination restoring the foliaceous morphotypes of Monostroma. Owing to the low concentration, the purification and structure elucidation of highly biologically active morphogenetic compounds are still challenging. Recently, it was found that only the combination of two specific bacteria from the Rhodobacteraceae and Flavobacteriaceae can completely recover the growth and morphogenesis of axenic Ulva mutabilis cultures forming a symbiotic tripartite community by chemical communication. This review combines literature detailing evidences of bacteria-induced morphogenesis in Ulvales. A set of standardized experimental approaches is further proposed for the preparation of axenic algal tissues, bacteria isolation, co-cultivation experiments, and the analysis of the chemosphere. PMID:25784916

  10. Tree species richness of upper Amazonian forests

    OpenAIRE

    Gentry, Alwyn H.

    1988-01-01

    Upper Amazonian data for tree species richness in 1-hectare plots are reported. All plants ≥10 cm diameter were censused and identified in six plots in Amazonian Peru and one on the Venezuela-Brazil border. The two plots from the everwet forests near Iquitos, Peru, are the most species-rich in the world, with ≈300 species ≥10 cm diameter in single hectares; all of the Peruvian plots are among the most species-rich ever reported. Contrary to accepted opinion, upper Amazonian forest, and perhap...

  11. Species - San Diego Co. [ds121

    Data.gov (United States)

    California Natural Resource Agency — This is the Biological Observation Database point layer representing baseline observations of sensitive species (as defined by the MSCP) throughout San Diego County....

  12. Species packing, and what competition minimizes.

    Science.gov (United States)

    Arthur, R M

    1969-12-01

    Species competing exclusively for renewing resources are shown to obey simultaneous differential equations equivalent to the conditions for minimizing a certain quadratic form. In this sense competition acts to select species abundances giving the best least-squares fit in an expression [Formula: see text] Thus the number of species which can coexist competitively is limited mostly by the inequality of the interspecies competition coefficients and not appreciably by their magnitude. Seasonality and number of resources become the main factors limiting the number of coexisting species.

  13. Diversity of Lophodermium species on pines

    Directory of Open Access Journals (Sweden)

    Lazarev Vladimir S.

    2004-01-01

    Full Text Available Multiannual study of needle-cast disease on pines shows that Lophodermium species, as well as other widely-ranging micro-organism species, are characterized by high variability in morphology, physiology, biology pathogenic characters, epiphytotiology and other characteristics, which points to the assumption on the existence of biotypes, forms or still unidentified species in this genus. This paper presents the study results which contribute to the elucidation of the confusion regarding the genus name Lophodermium and the species, biotypes or forms described in the genus.

  14. A Five-Species Jungle Game.

    Science.gov (United States)

    Kang, Yibin; Pan, Qiuhui; Wang, Xueting; He, Mingfeng

    2016-01-01

    In this paper, we investigate the five-species Jungle game in the framework of evolutionary game theory. We address the coexistence and biodiversity of the system using mean-field theory and Monte Carlo simulations. Then, we find that the inhibition from the bottom-level species to the top-level species can be critical factors that affect biodiversity, no matter how it is distributed, whether homogeneously well mixed or structured. We also find that predators' different preferences for food affect species' coexistence.

  15. Drug delivery systems in domestic animal species.

    Science.gov (United States)

    Brayden, David J; Oudot, Emilie J M; Baird, Alan W

    2010-01-01

    Delivery of biologically active agents to animals is often perceived to be the poor relation of human drug delivery. Yet this field has a long and successful history of species-specific device and formulation development, ranging from simple approaches and devices used in production animals to more sophisticated formulations and approaches for a wide range of species. While several technologies using biodegradable polymers have been successfully marketed in a range of veterinary and human products, the transfer of delivery technologies has not been similarly applied across species. This may be due to a combination of specific technical requirements for use of devices in different species, inter-species pharmacokinetic, pharmacodynamic and physiological differences, and distinct market drivers for drug classes used in companion and food-producing animals. This chapter reviews selected commercialised and research-based parenteral and non-parenteral veterinary drug delivery technologies in selected domestic species. Emphasis is also placed on the impact of endogenous drug transporters on drug distribution characteristics in different species. In vitro models used to investigate carrier-dependent transport are reviewed. Species-specific expression of transporters in several tissues can account for inter-animal or inter-species pharmacokinetic variability, lack of predictability of drug efficacy, and potential drug-drug interactions.

  16. Metabolite production by species of Stemphylium

    DEFF Research Database (Denmark)

    Olsen, Kresten Jon Kromphardt; Rossman, Amy; Andersen, Birgitte

    2018-01-01

    Morphology and phylogeny has been used to distinguish members of the plant pathogenic fungal genus Stemphylium. A third method for distinguishing species is by chemotaxonomy. The main goal of the present study was to investigate the chemical potential of Stemphylium via HPLC-UV-MS analysis, while...... also exploring the potential of chemotaxonomy as a robust identification method for Stemphylium. Several species were found to have species-specific metabolites, while other species were distinguishable by a broader metabolic profile rather than specific metabolites. Many previously described...

  17. Use of species-specific PCR for the identification of 10 sea cucumber species

    Science.gov (United States)

    Wen, Jing; Zeng, Ling

    2014-11-01

    We developed a species-specific PCR method to identify species among dehydrated products of 10 sea cucumber species. Ten reverse species-specific primers designed from the 16S rRNA gene, in combination with one forward universal primer, generated PCR fragments of ca. 270 bp length for each species. The specificity of the PCR assay was tested with DNA of samples of 21 sea cucumber species. Amplification was observed in specific species only. The species-specific PCR method we developed was successfully applied to authenticate species of commercial products of dehydrated sea cucumber, and was proven to be a useful, rapid, and low-cost technique to identify the origin of the sea cucumber product.

  18. Relating species abundance distributions to species-area curves in two Mediterranean-type shrublands

    Science.gov (United States)

    Keeley, Jon E.

    2003-01-01

    Based on both theoretical and empirical studies there is evidence that different species abundance distributions underlie different species-area relationships. Here I show that Australian and Californian shrubland communities (at the scale from 1 to 1000 m2) exhibit different species-area relationships and different species abundance patterns. The species-area relationship in Australian heathlands best fits an exponential model and species abundance (based on both density and cover) follows a narrow log normal distribution. In contrast, the species-area relationship in Californian shrublands is best fit with the power model and, although species abundance appears to fit a log normal distribution, the distribution is much broader than in Australian heathlands. I hypothesize that the primary driver of these differences is the abundance of small-stature annual species in California and the lack of annuals in Australian heathlands. Species-area is best fit by an exponential model in Australian heathlands because the bulk of the species are common and thus the species-area curves initially rise rapidly between 1 and 100 m2. Annuals in Californian shrublands generate very broad species abundance distributions with many uncommon or rare species. The power function is a better model in these communities because richness increases slowly from 1 to 100 m2 but more rapidly between 100 and 1000 m2due to the abundance of rare or uncommon species that are more likely to be encountered at coarser spatial scales. The implications of this study are that both the exponential and power function models are legitimate representations of species-area relationships in different plant communities. Also, structural differences in community organization, arising from different species abundance distributions, may lead to different species-area curves, and this may be tied to patterns of life form distribution.

  19. Acrotritia species (Acari: Oribatida: Euphthiracaridae) from China with description of a new species.

    Science.gov (United States)

    Liu, Dong; Chen, Jun

    2015-03-24

    In this paper, eight species of Acrotritia (Acari: Oribatida: Euphthiracaridae) are identified, including a new species, Acrotritia tibetensis sp. nov., and four newly recorded species from China: Acrotritia gracile (Niedbała, 2000), Acrotritia hauseri (Mahunka, 1991), Acrotritia refracta (Niedbała, 1998) and Acrotritia simile (Mahunka, 1982). An updated diagnosis of the genus and remarks on some known species are presented, the validity of species A. hauseri is discussed, and a key to Chinese known species of Acrotritia is also provided.

  20. Two new Neotropical species of Drosophila peruensis species group (Diptera, Drosophilidae

    Directory of Open Access Journals (Sweden)

    Jonas S. Döge

    2011-12-01

    Full Text Available The Drosophila peruensis species group was recently proposed and includes four taxa: D. atalaia Vilela & Sene, 1982, D. boraceia Vilela & Val, 2004, D. pauliceia Ratcov & Vilela, 2007, and D. peruensis Wheeler, 1959. All these species have most of setae or setulae of mesonotum arinsing from dark spots, wings with crossveins darker (except in D. atalaia and hypandrium squared-shaped mostly fused to gonopods. Here, we describe two new species, Drosophila itacorubi sp. nov. and Drosophila paraitacorubi sp. nov., belonging to this species group. The male genitalia of these species are figured. An identification key to the D. peruensis species group is provided.

  1. The species velocity of trees in Alaska

    Science.gov (United States)

    Morrison, B. D.; Napier, J.; de Lafontaine, G.; Heath, K.; Li, B.; Hu, F.; Greenberg, J. A.

    2017-12-01

    Anthropogenic climate change has motivated interest in the paleo record to enhance our knowledge about past vegetation responses to climate change and help understand potential responses in the future. Additionally, polar regions currently experience the most rapid rates of climate change globally, prompting concern over changes in the ecological composition of high latitude ecosystems. Recent analyses have attempted to construct methods to estimate a species' ability to track climate change by computing climate velocity; a measure of the rate of climate displacement across a landscape which may indicate the speed an organism must migrate to keep pace with climate change. However, a challenge to using climate velocity in understanding range shifts is a lack of species-specificity in the velocity calculations: climate velocity does not actually use any species data in its analysis. To solve the shortcomings of climate velocity in estimating species displacement rates, we computed the "species velocity" of white spruce, green and grey alder populations across the state of Alaska from the Last Glacial Maximum (LGM) to today. Species velocity represents the rate and direction a species is required to migrate to keep pace with a changing climate following the LGM. We used a species distribution model to determine past and present white spruce and alder distributions using statistically downscaled climate data at 60m. Species velocity was then derived from the change in species distribution per year by the change in distribution over Alaska (km/yr). High velocities indicate locations where the species environmental envelope is changing drastically and must disperse rapidly to survive climate change. As a result, high velocity regions are more vulnerable to distribution shifts and higher risk of local extinction. Conversely, low species velocities indicate locations where the local climate envelope is shifting relatively slowly, reducing the stress to disperse quickly

  2. Factors influencing when species are first named and estimating global species richness

    Directory of Open Access Journals (Sweden)

    Mark J. Costello

    2015-07-01

    Full Text Available Estimates of global species richness should consider what factors influence the rate of species discovery at global scales. However, past studies only considered regional scales and/or samples representing <0.4% of all named species. Here, we analysed trends in the rate of description for all fish species (2% of all named species. We found that the number of species described has slowed for (a brackish compared to marine and freshwater species, (b large compared to small sized fish, (c geographically widespread compared to localised, (d species occurring in the tropics and northern hemisphere compared to southern hemisphere, and (e neritic (coastal species compared to pelagic (offshore species. Most (68% of the variation in year of description was related to geographic location and depth, and contrary to expectations, body size was a minor factor at just 6% (on a standardised scale. Thus most undiscovered species will have small geographic ranges, but will not necessarily be of smaller body size than currently known species. Accordingly, global assessments of how many species may exist on Earth need to account for geographic variation.

  3. In vitro propagation of Fraxinus species

    Science.gov (United States)

    J.W. Van Sambeek; J.E. Preece

    2007-01-01

    The genus Fraxinus, a member of the Oleaceae family, includes over 65 ash species native to the temperate regions of the northern hemisphere (Miller, 1955). Several of the ash species are important forest trees noted for their tough, highly resistant to shock, straight grained wood as well as being excellent shade trees for parks and residential...

  4. Aphid (Hemiptera: Aphididae) species determined on herbaceous ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-06-17

    Jun 17, 2009 ... As a result, total of 28 aphid species belonging to 14 genus and 4 tribes of the super family. Aphidoidea were determined. ... species of Aphidoidea family attack various plants, infest- ing leaves, terms, fruits and roots ... Aphids were collected from their host plants with a fine brush and put in to a tube which ...

  5. Species richness, area and climate correlates

    DEFF Research Database (Denmark)

    Nogues, David Bravo; Bastos Araujo, Miguel

    2006-01-01

    Aim Species richness-area theory predicts that more species should be found if one samples a larger area. To avoid biases from comparing species richness in areas of very different sizes, area is often controlled by counting the numbers of co-occupying species in near-equal area grid cells...... affects: (1) the selection of climate variables entering a species richness model; and (2) the accuracy of models in predicting species richness in unsampled grid cells. Location Western Europe. Methods Models are developed for European plant, breeding bird, mammal and herptile species richness using...... seven climate variables. Generalized additive models are used to relate species richness, climate and area. Results We found that variation in the grid cell area was large (50 × 50 km: 8-3311 km2; 220 × 220: 193-55,100 km2), but this did not affect the selection of variables in the models. Similarly...

  6. Two new Orchidantha species (Lowiaceae) from Borneo

    NARCIS (Netherlands)

    Poulsen, A.D.; Leong-Škorničková, J.

    2017-01-01

    Two new Orchidantha species discovered in Sarawak, O. micrantha and O. megalantha, are described and illustrated. They may well represent the species with the smallest and the largest flowers currently known in the genus and certainly from Borneo. With its small flowers, O. micrantha is similar to

  7. Invasive plant species in hardwood tree plantations

    Science.gov (United States)

    Rochelle R. Beasley; Paula M. Pijut

    2010-01-01

    Invasive plants are species that can grow and spread aggressively, mature quickly, and invade an ecosystem causing economic and environmental damage. Invasive plants usually invade disturbed areas, but can also colonize small areas quickly, and may spread and dominate large areas in a few short years. Invasive plant species displace native or desirable forest...

  8. The Invasive Plant Species Education Guide

    Science.gov (United States)

    Mason, Kevin; James, Krista; Carlson, Kitrina; D'Angelo, Jean

    2010-01-01

    To help high school students gain a solid understanding of invasive plant species, university faculty and students from the University of Wisconsin-Stout (UW-Stout) and a local high school teacher worked together to develop the Invasive Plant Species (IPS) Education Guide. The IPS Education Guide includes nine lessons that give students an…

  9. Preliminary observations on the species composition and ...

    African Journals Online (AJOL)

    Majority of the mushrooms appear during the rain season and are equally available during the short and long rains. This suggests that most species will grow well throughout the year whenever moisture level in the substrate is adequate irrespective of the season. Some of the species especially the Polypores (Ganoderma ...

  10. Toward reassessing data-deficient species.

    Science.gov (United States)

    Bland, Lucie M; Bielby, Jon; Kearney, Stephen; Orme, C David L; Watson, James E M; Collen, Ben

    2017-06-01

    One in 6 species (13,465 species) on the International Union for Conservation of Nature (IUCN) Red List is classified as data deficient due to lack of information on their taxonomy, population status, or impact of threats. Despite the chance that many are at high risk of extinction, data-deficient species are typically excluded from global and local conservation priorities, as well as funding schemes. The number of data-deficient species will greatly increase as the IUCN Red List becomes more inclusive of poorly known and speciose groups. A strategic approach is urgently needed to enhance the conservation value of data-deficient assessments. To develop this, we reviewed 2879 data-deficient assessments in 6 animal groups and identified 8 main justifications for assigning data-deficient status (type series, few records, old records, uncertain provenance, uncertain population status or distribution, uncertain threats, taxonomic uncertainty, and new species). Assigning a consistent set of justification tags (i.e., consistent assignment to assessment justifications) to species classified as data deficient is a simple way to achieve more strategic assessments. Such tags would clarify the causes of data deficiency; facilitate the prediction of extinction risk; facilitate comparisons of data deficiency among taxonomic groups; and help prioritize species for reassessment. With renewed efforts, it could be straightforward to prevent thousands of data-deficient species slipping unnoticed toward extinction. © 2016 Society for Conservation Biology.

  11. Taxonomy of Penicillium citrinum and related species

    NARCIS (Netherlands)

    Houbraken, J.; Frisvad, J.C.; Samson, R.A.

    2010-01-01

    Penicillium citrinum and related species have been examined using a combination of partial beta-tubulin, calmodulin and ITS sequence data, extrolite patterns and phenotypic characters. It is concluded that seven species belong to the series Citrina. Penicillium sizovae and Penicillium steckii are

  12. Alkaloids of some Asian Sedum species

    NARCIS (Netherlands)

    Kim, JH; THart, H; Stevens, JF

    The leafy parts of 16 Asian species belonging to the three sections of Sedum were investigated for the presence of alkaloids. Only in seven species of Sedum sect. Sedum were alkaloids found. Sedum bulbiferum, S. japonicum, S. lepidopodium, S. morrisomensis, S. oryzifolium, S. polytrichoides and S.

  13. Detrimental effects of species of Tenthredinidae (Insecta ...

    African Journals Online (AJOL)

    The detrimental effects of these species are especially constituted by larval forms. Larva damages plants by eating plant tissue, forming gal and opening galleries in leaf, stem and bud of plants. These harmful species can be controlled with biological, cultural and chemical methods. The control methods change according to ...

  14. SERI Aquatic Species Program: 1983 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    1984-03-01

    During 1983 research was carried out under three tasks: biological, engineering, and analysis. Biological research was aimed at screening for promising species of microalgae, macroalgae, and emergent plants that could be cultivated for energy products. Promising species were studied further to improve yields.

  15. Invasive Species - A Threat to the Homeland?

    Science.gov (United States)

    2003-04-07

    species of weeds, diseases and organisms on both my farm and the surrounding woodlands. Some of these species include soybean cyst nematode, soybean aphid ...of the almonds, 92.2 percent of the grapes, 77.8 percent of the lettuce , 75.5 percent of the strawberries, 47 percent of the tomatoes, and 33.8

  16. Vanishing Species: The Planet in Crisis

    Indian Academy of Sciences (India)

    IAS Admin

    riorating environmental quality, concurrent evolution of new species is also ... sudden climatic change, rise in the sea level, volcanic eruptions. Species evolution and extinction are very much a part of the evolutionary history of the biotic world. The five big .... rainforest to coral reefs are destroyed or extensively modified for.

  17. Invasive species overarching priorities to 2029

    Science.gov (United States)

    Kelly Burnett; Susan J. Frankel; Melody Keena; Mee-Sook Kim; Ned B. Klopfenstein; Michael E. Ostry; Carolyn Hull Sieg

    2010-01-01

    Invasive species are one of the greatest threats to forest, range, aquatic, and urban forest ecosystem health. They contribute to the endangerment of native species and may lead to other severe ecological and financial consequences in our Nation’s wildlands and urban forests. Costs the public pays for damage, losses, and control efforts are estimated at more than $138...

  18. Invasive Species Science Update (No. 1)

    Science.gov (United States)

    Mee-Sook Kim; Jack Butler

    2008-01-01

    This electronic newsletter (Invasive Species Science Update) is published by the Rocky Mountain Research Station (RMRS) Cross-Program, Interdisciplinary Project team on Invasive Species. This newsletter will be published 3 times per year and is intended to enhance communication among RMRS scientists, wildland managers, other partners, stakeholders, and customers about...

  19. Invasive species and climate change (Chapter 7)

    Science.gov (United States)

    Justin B. Runyon; Jack L. Butler; Megan M. Friggens; Susan E. Meyer; Sharlene E. Sing

    2012-01-01

    Invasive species present one of the greatest threats to the health and sustainability of ecosystems worldwide. Invasive plants, animals, and diseases are known to have significant negative effects on biological diversity and the ecological structure and functions of native ecosystems. Moreover, the economic cost imposed by invasive species is enormous—the damage...

  20. Invasive Species Science Update (No. 6)

    Science.gov (United States)

    Paula Fornwalt

    2013-01-01

    The sixth issue of the Rocky Mountain Research Station's (RMRS) Invasive Species Science Update is now complete. Published approximately once per year, this newsletter keeps managers and other users up-to-date with recently completed and ongoing research by RMRS scientists, and covers breaking news related to invasive species issues. The newsletter is produced by...

  1. Elucidating the Ramularia eucalypti species complex

    NARCIS (Netherlands)

    Videira, S.I.R.; Groenewald, J.Z.; Kolecka, A.; Haren, van L.; Boekhout, T.; Crous, P.W.

    2015-01-01

    The genus Ramularia includes numerous phytopathogenic species, several of which are economically important. Ramularia eucalypti is currently the only species of this genus known to infect Eucalyptus by causing severe leaf-spotting symptoms on this host. However, several isolates identified as R.

  2. Rapid molecular technique to distinguish Fusarium species

    CSIR Research Space (South Africa)

    Lodolo, EJ

    1993-03-01

    Full Text Available The nuclear DNA (nDNA) of different isolates of three closely related, toxin-producing Fusarium species, F. moniliforme, F. nygamai and F. napiforme, was compared to ascertain the sensitivity of a molecular method to distinguish these three species...

  3. ( Dialium guineense willd), a multipurpose tree species

    African Journals Online (AJOL)

    The velvet tamarind (Dialium guineense Willd) is one of the key species for domestication in Sub-Saharan Africa. In order to help the sustainable management and conservation of this species, its structural characteristics and ethnobotanical traits were studied in the 4 vegetation types (typical dense forest, degraded dense ...

  4. New species of haematozoa in Phalacrocoracidae and ...

    African Journals Online (AJOL)

    New species of haematozoa, namely Leucocytozoon ugwidi sp. nov. from the Cape Cormorant Phalacrocorax capensis and Haemoproteus skuae sp. nov. from the Subantarctic Skua Catharacta antarctica, are described. These are the first species to be recorded from the families Phalacrocoracidae and Stercorariidae, ...

  5. Xanthomendoza borealis - a bipolar lichen species

    DEFF Research Database (Denmark)

    LIndblom, Louise; Søchting, Ulrik

    It has been uncertain whether the two xanthorioid taxa known as Xanthoria mawsonii and Xanthomen-doza borealis truly are distinct species or if they should best be treated as one species. They are morphologically very similar, but inhabit two disjunct geographical areas, that is, circumpolar on t...

  6. Prevalence of Cryptosporidium species and Giardia intestinalis ...

    African Journals Online (AJOL)

    Cryptosporidium species and Giardia intestinalis cause diarrheal infections in humans and other vertebrate animals globally and are considered to be of great public health importance. The study was conducted to determine the prevalence Cryptosporidium species and G. intestinalis infections among patients attending ...

  7. Molecular characterization of thermophilic Campylobacter species ...

    African Journals Online (AJOL)

    We identified two species of thermophilic Campylobacter in companion dogs in Jos. Majority of C. jejuni were isolated from mucoid faeces while mixed infections of the two species were more common among diarrhoeic dogs. Pet owners should observe strict hand hygiene especially after handling dogs or their faeces to ...

  8. Estimating species trees from unrooted gene trees.

    Science.gov (United States)

    Liu, Liang; Yu, Lili

    2011-10-01

    In this study, we develop a distance method for inferring unrooted species trees from a collection of unrooted gene trees. The species tree is estimated by the neighbor joining (NJ) tree built from a distance matrix in which the distance between two species is defined as the average number of internodes between two species across gene trees, that is, average gene-tree internode distance. The distance method is named NJ(st) to distinguish it from the original NJ method. Under the coalescent model, we show that if gene trees are known or estimated correctly, the NJ(st) method is statistically consistent in estimating unrooted species trees. The simulation results suggest that NJ(st) and STAR (another coalescence-based method for inferring species trees) perform almost equally well in estimating topologies of species trees, whereas the Bayesian coalescence-based method, BEST, outperforms both NJ(st) and STAR. Unlike BEST and STAR, the NJ(st) method can take unrooted gene trees to infer species trees without using an outgroup. In addition, the NJ(st) method can handle missing data and is thus useful in phylogenomic studies in which data sets often contain missing loci for some individuals.

  9. Fractionation of radionuclide species in the environment

    International Nuclear Information System (INIS)

    Salbu, Brit

    2009-01-01

    Naturally occurring and artificially produced radionuclides in the environment may be present in different physico-chemical forms (i.e., radionuclide species) varying in size (nominal molecular mass), charge properties and valence, oxidation state, structure and morphology, density, degree of complexation, etc. Low molecular mass (LMM) species are believed to be mobile and potentially bioavailable, while high molecular mass (HMM) species such as colloids, polymers, pseudocolloids and particles are considered inert. Due to time-dependent transformation processes such as mobilisation of radionuclide species from solid phases or interactions of mobile and reactive radionuclide species with components in soils and sediments, the original distribution of radionuclides deposited in ecosystems will change over time. To assess the environmental impact from radionuclide contamination, information on radionuclide species deposited, interactions within affected ecosystems and the time-dependent distribution of radionuclide species influencing mobility and biological uptake is essential. The development of speciation techniques to characterize radionuclide species in waters, soils and sediments should therefore be essential for improving the prediction power of impact and risk assessment models. The present paper reviews available fractionation techniques which can be utilised for radionuclide speciation purposes

  10. Historical species losses in bumblebee evolution.

    Science.gov (United States)

    Condamine, Fabien L; Hines, Heather M

    2015-03-01

    Investigating how species coped with past environmental changes informs how modern species might face human-induced global changes, notably via the study of historical extinction, a dominant feature that has shaped current biodiversity patterns. The genus Bombus, which comprises 250 mostly cold-adapted species, is an iconic insect group sensitive to current global changes. Through a combination of habitat loss, pathogens and climate change, bumblebees have experienced major population declines, and several species are threatened with extinction. Using a time-calibrated tree of Bombus, we analyse their diversification dynamics and test hypotheses about the role of extinction during major environmental changes in their evolutionary history. These analyses support a history of fluctuating species dynamics with two periods of historical species loss in bumblebees. Dating estimates gauge that one of these events started after the middle Miocene climatic optimum and one during the early Pliocene. Both periods are coincident with global climate change that may have extirpated Bombus species. Interestingly, bumblebees experienced high diversification rates during the Plio-Pleistocene glaciations. We also found evidence for a major species loss in the past one million years that may be continuing today. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  11. In vitro fruiting of Armillaria species.

    Science.gov (United States)

    Jimmy L. Reaves; Michael. McWilliams

    1991-01-01

    Thirty-three different isolates of various Armillaria species were grown on sterilized orange slices under a controlled temperature and light regime. Nine isolates of A. ostoyae (North American Biological Species I, NABS I), three of NABS VII, one of NABS IX, one of NABS X, and two unidentified isolates formed basidiomes. Most...

  12. Some new or noteworthy species of Mortierella

    NARCIS (Netherlands)

    Gams, W.

    1976-01-01

    Twenty-two species of Mortierella are described and distributed over the sections defined by Gams (1970) which include the following new species: Section Pusilla: M. roseo-nana; Section Alpina: M. globalpina and M. polygonia Section Simplex: M. amoeboidea; Section Hygrophila : M. elongatula, M.

  13. Species hybridization in the genus Pinus

    Science.gov (United States)

    Peter W. Garrett

    1979-01-01

    Results of a breeding program in which a large number of pine species were tested indicate that a number of species and hybrids may be useful in the northeastern United States. Austrian black pine x Japanese black pine and hybrids containing Japanese red pine all had good growth rates. While none of the soft pines grew faster than eastern white pine, a number of...

  14. determination of vectorial potential of mansonia species

    African Journals Online (AJOL)

    2011-10-10

    Oct 10, 2011 ... Aedes species are known to transmit W. bancrofti parasites. Objective: To determining the potential of Mansonia species; Ma. africanus and Ma. uniformis in the transmission of W. bancrofti. Design: Cross sectional study. Setting: Villages in Tana Delta district, Kenya. Subjects: In-door collected mosquitoes.

  15. Species composition, abundance, distribution and habitat ...

    African Journals Online (AJOL)

    There were 371 captures of rodents and shrews from live-trapping and 73 captures from snaps. Seven species of rodents (Stenocephalemys albipes, Lophuromys flavopunctatus, Arvicanthis abyssinicus, Desmomys harringtoni, Mastomys natalensis, Mus mahomet and Rattus rattus) and two species of shrews (Crocidura ...

  16. SPECIES DISTRBUTION WITHIN RIPARIAN LANDCAPE ALONG ...

    African Journals Online (AJOL)

    Osondu

    2011-12-30

    Dec 30, 2011 ... Data was collected on river bank morphology, altitude a.m.s.l., slope gradient, soil type, and tree species .... river channel. With distance from the channel soil type and moisture, slope gradient all varied so also change in species type, density and diversity ... defined in White-water forest Amazon Basin.

  17. Highlighting Astyanax Species Diversity through DNA Barcoding

    Science.gov (United States)

    Oliveira, Carlos Alexandre Miranda; de Melo, Filipe Augusto Gonçalves; Bertaco, Vinicius de Araújo; de Astarloa, Juan M. Díaz; Rosso, Juan J.; Foresti, Fausto; Oliveira, Claudio

    2016-01-01

    DNA barcoding has been used extensively to solve taxonomic questions and identify new species. Neotropical fishes are found in a wide variety of shapes and sizes, with a large number of species yet to be described, many of which are very difficult to identify. Characidae is the most species-rich family of the Characiformes, and many of its genera are affected by taxonomic uncertainties, including the widely-distributed, species-rich genus Astyanax. In this study, we present an extensive analysis of Astyanax covering almost its entire area of occurrence, based on DNA barcoding. The use of different approaches (ABGD, GMYC and BIN) to the clustering of the sequences revealed ample consistency in the results obtained by the initial cutoff value of 2% divergence for putative species in the Neighbor-Joining analysis using the Kimura-2-parameter model. The results indicate the existence of five Astyanax lineages. Some groups, such as that composed by the trans-Andean forms, are mostly composed of well-defined species, and in others a number of nominal species are clustered together, hampering the delimitation of species, which in many cases proved impossible. The results confirm the extreme complexity of the systematics of the genus Astyanax and show that DNA barcoding can be an useful tool to address these complexes questions. PMID:27992537

  18. antimicrobial susceptibility pattern of Salmonella species

    African Journals Online (AJOL)

    user

    ABSTRACT. Treatment of enteric fever is increasingly becoming very challenging due to the increasing wave of antibiotic resistance. This study is a review of the contemporary antimicrobial susceptibility pattern of. Salmonella species. The antimicrobial susceptibility pattern of Salmonella species to a wide range of.

  19. Species identification and antifungal susceptibility pattern of ...

    African Journals Online (AJOL)

    Dalia Saad ElFeky

    2015-10-23

    Oct 23, 2015 ... Abstract Vulvovaginal candidiasis (VVC) remains one of the most common infections of the female genital tract. Correct identification of the isolated Candida species is essential to direct the empirical antifungal therapy. Objectives: This local study was conducted to identify the spectrum of Candida species ...

  20. Ensemble habitat mapping of invasive plant species

    Science.gov (United States)

    Stohlgren, T.J.; Ma, P.; Kumar, S.; Rocca, M.; Morisette, J.T.; Jarnevich, C.S.; Benson, N.

    2010-01-01

    Ensemble species distribution models combine the strengths of several species environmental matching models, while minimizing the weakness of any one model. Ensemble models may be particularly useful in risk analysis of recently arrived, harmful invasive species because species may not yet have spread to all suitable habitats, leaving species-environment relationships difficult to determine. We tested five individual models (logistic regression, boosted regression trees, random forest, multivariate adaptive regression splines (MARS), and maximum entropy model or Maxent) and ensemble modeling for selected nonnative plant species in Yellowstone and Grand Teton National Parks, Wyoming; Sequoia and Kings Canyon National Parks, California, and areas of interior Alaska. The models are based on field data provided by the park staffs, combined with topographic, climatic, and vegetation predictors derived from satellite data. For the four invasive plant species tested, ensemble models were the only models that ranked in the top three models for both field validation and test data. Ensemble models may be more robust than individual species-environment matching models for risk analysis. ?? 2010 Society for Risk Analysis.

  1. Finessing atlas data for species distribution models

    NARCIS (Netherlands)

    Niamir, A.; Skidmore, A.K.; Toxopeus, A.G.; Munoz, A.R.; Real, R.

    2011-01-01

    Aim The spatial resolution of species atlases and therefore resulting model predictions are often too coarse for local applications. Collecting distribution data at a finer resolution for large numbers of species requires a comprehensive sampling effort, making it impractical and expensive. This

  2. Fatal attraction: rare species in the spotlight.

    Science.gov (United States)

    Angulo, Elena; Deves, Anne-Laure; Saint Jalmes, Michel; Courchamp, Franck

    2009-04-07

    The exploitation of rare and endangered species can end in the species's extinction because the increased value people associate with rarity increases the economic incentive to exploit the last individuals, creating a positive feedback loop. This recently proposed concept, called the anthropogenic Allee effect (AAE), relies on the assumption that people do value rarity, but this remains to be established. Moreover, it also remains to be determined whether attraction to rarity is a trait confined to a minority of hobbyists (e.g. wildlife collectors, exotic pet owners) or characteristic of the general public. We estimated how much the general public valued rare species compared with common ones, using five different metrics related to personal investment: time spent, physical effort, unpleasantness, economic investment and risk. We surveyed the visitors of a zoo. To see the rare species, the visitors to the zoo invested more time in searching and contemplation, they were ready to expend more physical effort, they tolerated more unpleasant conditions, they were willing to pay more and, finally, they risked more to obtain (steal) a rare species. Our results provide substantial evidence of how the general public places more value on rare species, compared with common species. This confirms the AAE as an actual process, which in addition concerns a large part of the population. This has important consequences for the conservation of species that are rare now, or that could become so in the future.

  3. New species of Maerua (Capparaceae) from Angola

    NARCIS (Netherlands)

    Abreu, J.A.; Martins, E.S.; Catarino, L.

    2014-01-01

    Genus Maerua has around 60 species represented on the African continent, of which three have been reported for Angola. Two new species of Maerua (Capparaceae) from Angola are here described. Both are closely similar to M. juncea subsp. juncea, being distinguished by floral traits such as the

  4. New Species of Orchids from Vietnam

    Directory of Open Access Journals (Sweden)

    Leonid V. Averyanov

    2007-12-01

    Full Text Available Identification of herbarium specimens collected in course of field exploration works in Vietnam during 2005-2007 revealed ten species of orchids new for science. Illustrated descriptions are provided for each discovered species, which are named as Anoectochilus papillosus, Arundina caespitosa, Bulbophyllum paraemarginatum, B. sinhoënse, Cheirostylis foliosa, Goodyera rhombodoides, Liparis rivularis, Oberonia multidentata, O. trichophora and Sunipia nigricans.

  5. Antibiotic susceptibilities of Salmonella species prevalent among ...

    African Journals Online (AJOL)

    This study was conducted to assess the prevalence of Salmonella species among children having diarrhea in Katsina State, Nigeria. A total of 220 diarrhea stool samples of children aged five years and below (0-5 years) were collected and screened for Salmonella species using culture technique. Presumptively positive ...

  6. Endangered Species (Plants). LC Science Tracer Bullet.

    Science.gov (United States)

    Niskern, Diana, Comp.

    This guide is intended for those who wish to study the literature dealing with various aspects of endangered plant species. This document includes the following sections, some of which are bibliographies: (1) "Introductions to the Topic"; (2) "Subject Headings" (for endangered species of plants used by the Library of Congress); (3) "General…

  7. Endangered Species: Real Life in Two Dimensions

    Science.gov (United States)

    Henderson, Lynette K.

    2012-01-01

    The focus of "Endangered Species: Real Life in Two Dimensions" is to create awareness about a critical environmental issue. There is a special urgency to this project because large numbers of animal species are currently endangered or on the brink of extinction. In addition to being enlightened about this important topic through research, students…

  8. DNA species surveillance: Monitoring bushmeat poaching and ...

    African Journals Online (AJOL)

    DNA species identification has applications in such areas as forensic science, systematics, conservation genetics and agriculture. One key anthropogenic activity threatening large wildlife fauna is illegal exploitation. In Kenya, species identification of raw and processed meat products remains a constraint to effective ...

  9. Catalogue of fish species of the Netherlands

    NARCIS (Netherlands)

    Nijssen, H.; Groot, de S.J.

    1974-01-01

    A catalogue of 179 fish species occurring in the fresh and coastal waters of the Netherlands is published. Scientific, Dutch and English names are given for each species as well as information on their abundance in the fresh waters of Holland and in the Dutch coastal waters within the twelve mile

  10. Novel Pestivirus Species in Pigs, Austria, 2015.

    Science.gov (United States)

    Lamp, Benjamin; Schwarz, Lukas; Högler, Sandra; Riedel, Christiane; Sinn, Leonie; Rebel-Bauder, Barbara; Weissenböck, Herbert; Ladinig, Andrea; Rümenapf, Till

    2017-07-01

    A novel pestivirus species was discovered in a piglet-producing farm in Austria during virologic examinations of congenital tremor cases. The emergence of this novel pestivirus species, provisionally termed Linda virus, in domestic pigs may have implications for classical swine fever virus surveillance and porcine health management.

  11. Energetic constraints on species coexistence in birds

    NARCIS (Netherlands)

    Pigot, Alexander L.; Tobias, Joseph A.; Jetz, Walter

    2016-01-01

    The association between species richness and ecosystem energy availability is one of the major geographic trends in biodiversity. It is often explained in terms of energetic constraints, such that coexistence among competing species is limited in low productivity environments. However, it has proven

  12. SHORT COMMUNICATION Vector species composition and malaria ...

    African Journals Online (AJOL)

    Wilkes et al., 1996). Information of mosquito species composition, abundance and dynamics are important in designing appropriate malaria control strategies. It was the aim of this study to identify the malaria vector species and their infectivity rates in Mkuzi village of Muheza. District in northern east Tanzania. The study was ...

  13. Emergent neutrality drives phytoplankton species coexistence

    Science.gov (United States)

    Segura, Angel M.; Calliari, Danilo; Kruk, Carla; Conde, Daniel; Bonilla, Sylvia; Fort, Hugo

    2011-01-01

    The mechanisms that drive species coexistence and community dynamics have long puzzled ecologists. Here, we explain species coexistence, size structure and diversity patterns in a phytoplankton community using a combination of four fundamental factors: organism traits, size-based constraints, hydrology and species competition. Using a ‘microscopic’ Lotka–Volterra competition (MLVC) model (i.e. with explicit recipes to compute its parameters), we provide a mechanistic explanation of species coexistence along a niche axis (i.e. organismic volume). We based our model on empirically measured quantities, minimal ecological assumptions and stochastic processes. In nature, we found aggregated patterns of species biovolume (i.e. clumps) along the volume axis and a peak in species richness. Both patterns were reproduced by the MLVC model. Observed clumps corresponded to niche zones (volumes) where species fitness was highest, or where fitness was equal among competing species. The latter implies the action of equalizing processes, which would suggest emergent neutrality as a plausible mechanism to explain community patterns. PMID:21177680

  14. ALIEN SPECIES: THEIR ROLE IN AMPHIBIAN POPULATION DECLINES AND RESTORATION

    Science.gov (United States)

    Alien species (also referred to as exotic, invasive, introduced, or normative species) have been implicated as causal agents in population declines of many amphibian species. Herein, we evaluate the relative contributions of alien species and other factors in adversely affecting ...

  15. Stochastic species abundance models involving special copulas

    Science.gov (United States)

    Huillet, Thierry E.

    2018-01-01

    Copulas offer a very general tool to describe the dependence structure of random variables supported by the hypercube. Inspired by problems of species abundances in Biology, we study three distinct toy models where copulas play a key role. In a first one, a Marshall-Olkin copula arises in a species extinction model with catastrophe. In a second one, a quasi-copula problem arises in a flagged species abundance model. In a third model, we study completely random species abundance models in the hypercube as those, not of product type, with uniform margins and singular. These can be understood from a singular copula supported by an inflated simplex. An exchangeable singular Dirichlet copula is also introduced, together with its induced completely random species abundance vector.

  16. Fisheries oceanography of northern pelagic fish species

    DEFF Research Database (Denmark)

    Tsoukali, Stavroula

    in the environment, and depending on species, eggs either drift/float in the water or are attached to the bottom close to each other. The larvae that hatch from the eggs grow in size continuously until they reach a certain size and become adults. The first few weeks of its life are the riskiest and most of the eggs....... The period of time that spawning takes place depends on the environmental conditions that each species has adapted to during the life of the species. Here, I have found that temperature is a significant factor that strongly affects egg development and survival. There are large differences in the temperature...... range that maximizes survival among different species, but the sensitivity of egg development rate in a degree of temperature increase is similar among the 32 species and populations I analysed. I also found that adults spawn at temperature conditions that are generally close to the egg preferences...

  17. The Porphyra species of Helgoland (Bangiales, Rhodophyta)

    Science.gov (United States)

    Kornmann, P.; Sahling, P.-H.

    1991-03-01

    This revision of seven Porphyra species of Helgoland was based on a study of the structure of their fertile thalli and the behaviour of their spores. Regarding the reproductive organization the species may be arranged in two groups. P. leucosticta and P. purpureo-violacea are obligate monoecious species. Asexual thalli have never been observed in the field. The other five species are generally dioecious. Isomorphic sexual thalli and asexually propagating ones are mixed in uniform populations. Carpospores originating from sexual fusion develop into the diploid Conchocelis phase. Sporangia of asexual plants, though homologous in formation, produce spores of different kinds: aplanospores that give rise to the vegetative thallus directly (in P. umbilicalis, P. insolita n. sp. and P. ochotensis) and spores that develop into haploid Conchocelis (in P. laciniata and in P. linearis). P. laciniata — formerly considered synonymous with P. purpurea — is an independent species.

  18. New species in Aspergillus section Terrei

    DEFF Research Database (Denmark)

    Samson, R. A.; Peterson, S. W.; Frisvad, Jens Christian

    2011-01-01

    . clade including the type isolate of A. niveus (CBS 115.27) constitutes a lineage closely related to A. carneus. Fennellia nivea, the hypothesized teleomorph is not related to this clade. Aspergillus allahabadii, A. niveus var. indicus, and two species originally placed in section Versicolores, A......Section Terrei of Aspergillus was studied using a polyphasic approach including sequence analysis of parts of the beta-tubulin and calmodulin genes and the ITS region, macro- and micromorphological analyses and examination of extrolite profiles to describe three new species in this section. Based....... floccosus, A. terreus var. africanus, A. terreus var. aureus, while Aspergillus hortai is recognised at species level. Aspergillus terreus NRRL 4017 is described as the new species A. pseudoterreus. Also included in section Terrei are some species formerly placed in sections Flavipedes and Versicolores. A...

  19. Allium species poisoning in dogs and cats

    Directory of Open Access Journals (Sweden)

    BS Salgado

    2011-01-01

    Full Text Available Dogs and cats are the animals that owners most frequently seek assistance for potential poisonings, and these species are frequently involved with toxicoses due to ingestion of poisonous food. Feeding human foodstuff to pets may prove itself dangerous for their health, similarly to what is observed in Allium species toxicosis. Allium species toxicosis is reported worldwide in several animal species, and the toxic principles present in them causes the transformation of hemoglobin into methemoglobin, consequently resulting in hemolytic anemia with Heinz body formation. The aim of this review is to analyze the clinicopathologic aspects and therapeutic approach of this serious toxicosis of dogs and cats in order to give knowledge to veterinarians about Allium species toxicosis, and subsequently allow them to correctly diagnose this disease when facing it; and to educate pet owners to not feed their animals with Allium-containg food in order to better control this particular life-threatening toxicosis.

  20. Invasive species unchecked by climate - response

    DEFF Research Database (Denmark)

    Burrows, Michael T.; Schoeman, David S.; Duarte, Carlos M.

    2012-01-01

    Hulme points out that observed rates of range expansion by invasive alien species are higher than the median speed of isotherm movement over the past 50 years, which in turn has outpaced the rates of climate-associated range changes of marine and terrestrial species. This is not surprising, given...... the many ecological and anthropogenic processes that combine to facilitate the translocation of invasive species and the subsequent expansion of their populations. Successful alien species have been observed to rapidly expand their ranges until some limit, typically climate-imposed, is reached. Comparisons...... of climate-change-induced range shifts between native and alien species are meaningful only after the initial invasive spread has reached a stable range boundary. A focus on regions with high velocities of climate change, and on regions such as the tropics where novel thermal niches are being created, should...

  1. New species of Moenkhausia Eigenmann, 1903 (Characiformes: Characidae with comments on the Moenkhausia oligolepis species complex

    Directory of Open Access Journals (Sweden)

    Ricardo C. Benine

    Full Text Available A new species of Moenkhausia is described from tributaries of the rio Paraguay, Brazil. The new species is diagnosed from congeners by characters related to body coloration, the number of lateral line scales, the degree of poring of the lateral line, and number of scales rows above and below the lateral line. Molecular analyses using partial sequences of the mitochondrial gene Cytochrome Oxidase I from specimens of the new species and specimens belonging to morphologically similar species demonstrated that the new species is easily differentiated by their high genetic distance and by their position in the phylogenetic hypothesis obtained through the Maximum Parsimony methodology. The analyses of three samples of M. oligolepis also revealed that they have high genetic distances and belong to different monophyletic groups suggesting that this species corresponds to a species complex rather than a single species.

  2. 75 FR 38069 - Injurious Wildlife Species; Listing the Boa Constrictor, Four Python Species, and Four Anaconda...

    Science.gov (United States)

    2010-07-01

    ... Python Species, and Four Anaconda Species as Injurious Reptiles AGENCY: Fish and Wildlife Service... regulations to add Indian python (Python molurus, including Burmese python Python molurus bivittatus), reticulated python (Broghammerus reticulatus or Python reticulatus), Northern African python (Python sebae...

  3. Practically delineating bacterial species with genealogical concordance.

    Science.gov (United States)

    Venter, Stephanus N; Palmer, Marike; Beukes, Chrizelle W; Chan, Wai-Yin; Shin, Giyoon; van Zyl, Elritha; Seale, Tarren; Coutinho, Teresa A; Steenkamp, Emma T

    2017-10-01

    Bacterial species are commonly defined by applying a set of predetermined criteria, including DNA-DNA hybridization values, 16S rRNA gene sequence similarity, phenotypic data as well as genome-based criteria such as average nucleotide identity or digital DNA-DNA hybridization. These criteria mostly allow for the delimitation of taxa that resemble typical bacterial species. Their application is often complicated when the objective is to delineate new species that are characterized by significant population-level diversity or recent speciation. However, we believe that these complexities and limitations can be easily circumvented by recognizing that bacterial species represent unique and exclusive assemblages of diversity. Within such a framework, methods that account for the population processes involved in species evolution are used to infer species boundaries. A method such as genealogical concordance analysis is well suited to delineate a putative species. The existence of the new taxon is then interrogated using an array of traditional and genome-based characters. By making use of taxa in the genera Pantoea, Paraburkholderia and Escherichia we demonstrate in a step-wise process how genealogical concordance can be used to delimit a bacterial species. Genetic, phenotypic and biological criteria were used to provide independent lines of evidence for the existence of that taxon. Our six-step approach to species recognition is straightforward and applicable to bacterial species especially in the post-genomic era, with increased availability of whole genome sequences. In fact, our results indicated that a combined genome-based comparative and evolutionary approach would be the preferred alternative for delineating coherent bacterial taxa.

  4. Spatial complementarity and the coexistence of species.

    Science.gov (United States)

    Velázquez, Jorge; Garrahan, Juan P; Eichhorn, Markus P

    2014-01-01

    Coexistence of apparently similar species remains an enduring paradox in ecology. Spatial structure has been predicted to enable coexistence even when population-level models predict competitive exclusion if it causes each species to limit its own population more than that of its competitor. Nevertheless, existing hypotheses conflict with regard to whether clustering favours or precludes coexistence. The spatial segregation hypothesis predicts that in clustered populations the frequency of intra-specific interactions will be increased, causing each species to be self-limiting. Alternatively, individuals of the same species might compete over greater distances, known as heteromyopia, breaking down clusters and opening space for a second species to invade. In this study we create an individual-based model in homogeneous two-dimensional space for two putative sessile species differing only in their demographic rates and the range and strength of their competitive interactions. We fully characterise the parameter space within which coexistence occurs beyond population-level predictions, thereby revealing a region of coexistence generated by a previously-unrecognised process which we term the triadic mechanism. Here coexistence occurs due to the ability of a second generation of offspring of the rarer species to escape competition from their ancestors. We diagnose the conditions under which each of three spatial coexistence mechanisms operates and their characteristic spatial signatures. Deriving insights from a novel metric - ecological pressure - we demonstrate that coexistence is not solely determined by features of the numerically-dominant species. This results in a common framework for predicting, given any pair of species and knowledge of the relevant parameters, whether they will coexist, the mechanism by which they will do so, and the resultant spatial pattern of the community. Spatial coexistence arises from complementary combinations of traits in each species

  5. Handling Big Data of Alien Species in Europe: The European Alien Species Information Network Geodatabase

    OpenAIRE

    DERIU IVAN; D'AMICO FABIO; TSIAMIS KONSTANTINOS; GERVASINI EUGENIO; DE JESUS CARDOSO ANA

    2017-01-01

    Building and managing large datasets of alien species is crucial to research, management, and control of biological invasions. To this end, the European Alien Species Information Network (EASIN) platform aggregates, integrates, and harmonizes spatio-temporal data regarding alien species in Europe, including both invasive and non-invasive alien species. These data are stored in the EASIN Geodatabase after their harvesting from relevant sources in the frame of a global and European databases pa...

  6. Dna c-values of 20 invasive alien species and 3 native species in south china

    OpenAIRE

    Gong Ni; Wang Yu-Tao; Björn Lars Olof; Li Shao-Shan

    2014-01-01

    Cultivated fields and forests in South China are experiencing serious damage due to invasive alien plants. We investigated the relation between DNA C-values and invasiveness. The DNA C-values of 23 species ranged from 0.39 pg to 3.37 pg. Herbs, perennials and native species had higher mean DNA C-values than shrubs, annuals and invasive alien species. DNA C-values decreased with increasing invasiveness. Paederia scandens, a harmful native species, has the lo...

  7. Neosilba (Tephritoidea: Lonchaeidae) species reared from coffee in Brazil, with description of a new species

    Energy Technology Data Exchange (ETDEWEB)

    Striki, Pedro Carlos; Prado, Angelo Pires do, E-mail: apprado@unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Biologia. Dept. de Parasitologia

    2006-07-01

    Neosilba species are believed to be secondary invaders of fruit, so, little attention has been paid to its presence in coffee fruits. In this article we present a key to Neosilba species present in coffee fruits and describe a new species that is considered a primary invader. We hope this will help researchers working with coffee fruits to better quantify the economic importance of Neosilba species associated with coffee fruits. (author)

  8. Neosilba (Tephritoidea: Lonchaeidae) species reared from coffee in Brazil, with description of a new species

    International Nuclear Information System (INIS)

    Striki, Pedro Carlos; Prado, Angelo Pires do

    2006-01-01

    Neosilba species are believed to be secondary invaders of fruit, so, little attention has been paid to its presence in coffee fruits. In this article we present a key to Neosilba species present in coffee fruits and describe a new species that is considered a primary invader. We hope this will help researchers working with coffee fruits to better quantify the economic importance of Neosilba species associated with coffee fruits. (author)

  9. Species distribution modelling for plant communities: Stacked single species or multivariate modelling approaches?

    Science.gov (United States)

    Emilie B. Henderson; Janet L. Ohmann; Matthew J. Gregory; Heather M. Roberts; Harold S.J. Zald

    2014-01-01

    Landscape management and conservation planning require maps of vegetation composition and structure over large regions. Species distribution models (SDMs) are often used for individual species, but projects mapping multiple species are rarer. We compare maps of plant community composition assembled by stacking results from many SDMs with multivariate maps constructed...

  10. Two new species of Omyomymar Schauff (Hymenoptera: Mymaridae from India with key to Oriental species

    Directory of Open Access Journals (Sweden)

    James Gowriprakash

    2016-11-01

    Full Text Available Two new species of Omyomymar Schauff viz., O. huberi sp. nov. and O. noyesi sp. nov., are described from Tamil Nadu, India. A key to Oriental Omyomymar species is provided with color images of new species for easy morphological diagnosis.

  11. Can dispersal investment explain why tall plant species achieve longer dispersal distances than short plant species?

    Science.gov (United States)

    Thomson, Fiona J; Letten, Andrew D; Tamme, Riin; Edwards, Will; Moles, Angela T

    2018-01-01

    Tall plant species disperse further distances than do short species, within and across dispersal syndromes, yet the driver underpinning this relationship is unclear. The ability of taller plants to invest more in dispersal structures may explain the positive relationship between plant height and dispersal distance. Here, we quantify the cross-species relationships between presence of dispersal structures, dispersal investment plant height and dispersal distance. Plant height, dispersal syndrome and dispersal investment data were collated for 1613 species from the literature, with dispersal distance data collated for 114 species. We find that species with high dispersal investment disperse further than do species with low dispersal investment. Tall species have a greater probability of having dispersal structures on their seeds compared with short species. For species with dispersal structures on their seeds, plant height is very weakly related to dispersal investment. Our results provide the first global confirmation of the dispersal investment-distance hypothesis, and show dispersal investment can be used for predicting species dispersal distances. However, our results and those of previous studies indicate plant height is still the best proxy for estimating species dispersal distances due to it being such a readily available plant trait. © 2017 Landcare Research. New Phytologist © 2017 New Phytologist Trust.

  12. Managing aquatic species of conservation concern in the face of climate change and invasive species.

    Science.gov (United States)

    Rahel, Frank J; Bierwagen, Britta; Taniguchi, Yoshinori

    2008-06-01

    The difficult task of managing species of conservation concern is likely to become even more challenging due to the interaction of climate change and invasive species. In addition to direct effects on habitat quality, climate change will foster the expansion of invasive species into new areas and magnify the effects of invasive species already present by altering competitive dominance, increasing predation rates, and enhancing the virulence of diseases. In some cases parapatric species may expand into new habitats and have detrimental effects that are similar to those of invading non-native species. The traditional strategy of isolating imperiled species in reserves may not be adequate if habitat conditions change beyond historic ranges or in ways that favor invasive species. The consequences of climate change will require a more active management paradigm that includes implementing habitat improvements that reduce the effects of climate change and creating migration barriers that prevent an influx of invasive species. Other management actions that should be considered include providing dispersal corridors that allow species to track environmental changes, translocating species to newly suitable habitats where migration is not possible, and developing action plans for the early detection and eradication of new invasive species.

  13. Protectiveness of Species Sensitivity Distribution Hazard Concentrations for Acute Toxicity Used in Endangered Species Risk Assessment

    Science.gov (United States)

    A primary objective of threatened and endangered species conservation is to ensure that chemical contaminants and other stressors do not adversely affect listed species. Assessments of the ecological risks of chemical exposures to listed species often rely on the use of surrogate...

  14. Estimating tree species richness from forest inventory plot data

    Science.gov (United States)

    Ronald E. McRoberts; Dacia M. Meneguzzo

    2007-01-01

    Montreal Process Criterion 1, Conservation of Biological Diversity, expresses species diversity in terms of number of forest dependent species. Species richness, defined as the total number of species present, is a common metric for analyzing species diversity. A crucial difficulty in estimating species richness from sample data obtained from sources such as inventory...

  15. Tree structural and species diversities in Okwangwo Forest, Cross ...

    African Journals Online (AJOL)

    Tree species were grouped into abundance classes. A total of 125 tree species belonging to 36 families and 96 genera were recorded in the area with Margaleffs index of species richness of 2.2754. Most (99) of the tree species encountered were threatened/endangered, 23 species were rare with only 3 tree species ...

  16. Woody Species Composition and Structure of the Gurra Farda ...

    African Journals Online (AJOL)

    Sixty six woody species belonging to 28 families were recorded in the forest. Moraceae was found to be the dominant family in the forest with 7 species comprising 10.6 % of the total species identified followed by Rubiaceae with 6 species or 9 % of the total woody species identified. From the identified plants five species ...

  17. Design and construction of "synthetic species".

    Directory of Open Access Journals (Sweden)

    Eduardo Moreno

    Full Text Available Synthetic biology is an area of biological research that combines science and engineering. Here, I merge the principles of synthetic biology and regulatory evolution to create a new species with a minimal set of known elements. Using preexisting transgenes and recessive mutations of Drosophila melanogaster, a transgenic population arises with small eyes and a different venation pattern that fulfils the criteria of a new species according to Mayr's Biological Species Concept. The population described here is the first transgenic organism that cannot hybridize with the original wild type population but remains fertile when crossed with other identical transgenic animals. I therefore propose the term "synthetic species" to distinguish it from "natural species", not only because it has been created by genetic manipulation, but also because it may never be able to survive outside the laboratory environment. The use of genetic engineering to design artificial species barriers could help us understand natural speciation and may have practical applications. For instance, the transition from transgenic organisms towards synthetic species could constitute a safety mechanism to avoid the hybridization of genetically modified animals with wild type populations, preserving biodiversity.

  18. Culex Species Mosquitoes and Zika Virus.

    Science.gov (United States)

    Huang, Yan-Jang S; Ayers, Victoria B; Lyons, Amy C; Unlu, Isik; Alto, Barry W; Cohnstaedt, Lee W; Higgs, Stephen; Vanlandingham, Dana L

    2016-10-01

    Recent reports of Zika virus (ZIKV) isolates from Culex species mosquitoes have resulted in concern regarding a lack of knowledge on the number of competent vector species for ZIKV transmission in the new world. Although observations in the field have demonstrated that ZIKV isolation can be made from Culex species mosquitoes, the detection of ZIKV in these mosquitoes is not proof of their involvement in a ZIKV transmission cycle. Detection may be due to recent feeding on a viremic vertebrate, and is not indicative of replication in the mosquito. In this study, susceptibility of recently colonized Culex species mosquitoes was investigated. The results showed a high degree of refractoriness among members of Culex pipiens complex to ZIKV even when exposed to high-titer bloodmeals. Our finding suggests that the likelihood of Culex species mosquitoes serving as secondary vectors for ZIKV is very low, therefore vector control strategies for ZIKV should remain focused on Aedes species mosquitoes. Our demonstration that Culex quinquefasciatus from Vero Beach, FL, is refractory to infection with ZIKV is especially important and timely. Based on our data, we would conclude that the autochthonous cases of Zika in Florida are not due to transmission by C. quinquefasciatus, and so control efforts should focus on other species, logically Aedes aegypti and Aedes albopictus.

  19. Species coexistence in a changing world

    Directory of Open Access Journals (Sweden)

    Fernando eValladares

    2015-10-01

    Full Text Available The consequences of global change for the maintenance of species diversity will depend on the sum of each species responses to the environment and on the interactions among them. A wide ecological literature supports that these species-specific responses can arise from factors related to life strategies, evolutionary history and intraspecific variation, and also from environmental variation in space and time. In the light of recent advances from coexistence theory combined with mechanistic explanations of diversity maintenance, we discuss how global change drivers can influence species coexistence. We revise the importance of both competition and facilitation for understanding coexistence in different ecosystems, address the influence of phylogenetic relatedness, functional traits, phenotypic plasticity and intraspecific variability, and discuss lessons learnt from invasion ecology. While most previous studies have focused their efforts on disentangling the mechanisms that maintain the biological diversity in species-rich ecosystems such as tropical forests, grasslands and coral reefs, we argue that much can be learnt from pauci-specific communities where functional variability within each species, together with demographic and stochastic processes becomes key to understand species interactions and eventually community responses to global change.

  20. Isoprene emission from tropical tree species.

    Science.gov (United States)

    Padhy, P K; Varshney, C K

    2005-05-01

    Foliar emission of isoprene was measured in nine commonly growing tree species of Delhi, India. Dynamic flow enclosure technique was used and gas samples were collected onto Tenax-GC/Carboseive cartridges, which were then attached to the sample injection system in the gas chromatograph (GC). Eluting compounds were analysed using a flame ionisation detector (FID). Out of the nine tree species, isoprene emission was found in six species (Eucalyptus sp., Ficus benghalensis, Ficus religiosa, Mangifera indica, Melia azedarach, and Syzygium jambolanum), whereas, in the remaining three tree species (Alstonia scholaris, Azadirachta indica, and Cassia fistula) no isoprene emission was detected or the levels of emission were negligible or below the detection limit (BDL). Among six tree species, the highest hourly emission (10.2 +/- 6.8 microg g(-1) leaf dry weight, average of five seasons) was observed in Ficus religiosa, while minimum emission was from Melia azedarach (2.2 +/- 4.9 microg g(-1) leaf dry weight, average of five seasons). Isoprene emission (average of six species), over five seasons, was found to vary between 3.9 and 8.5 microg g(-1) leaf dry weight during the rainy season. In addition, significant diurnal variation in isoprene emission was observed in each species. The preliminary estimate made in this study on the annual biogenic VOC emission from India may probably be the first of its kind from this part of the world.

  1. Pushing the pace of tree species migration.

    Directory of Open Access Journals (Sweden)

    Eli D Lazarus

    Full Text Available Plants and animals have responded to past climate changes by migrating with habitable environments, sometimes shifting the boundaries of their geographic ranges by tens of kilometers per year or more. Species migrating in response to present climate conditions, however, must contend with landscapes fragmented by anthropogenic disturbance. We consider this problem in the context of wind-dispersed tree species. Mechanisms of long-distance seed dispersal make these species capable of rapid migration rates. Models of species-front migration suggest that even tree species with the capacity for long-distance dispersal will be unable to keep pace with future spatial changes in temperature gradients, exclusive of habitat fragmentation effects. Here we present a numerical model that captures the salient dynamics of migration by long-distance dispersal for a generic tree species. We then use the model to explore the possible effects of assisted colonization within a fragmented landscape under a simulated tree-planting scheme. Our results suggest that an assisted-colonization program could accelerate species-front migration rates enough to match the speed of climate change, but such a program would involve an environmental-sustainability intervention at a massive scale.

  2. Genetic variability in three Amazon parrot species

    Directory of Open Access Journals (Sweden)

    IF. Lopes

    Full Text Available Parrots of the genus Amazona are among the most threatened species of the Order Pscittaciformes. This work describes allozyme polymorphisms in three Amazon parrot species - the Blue-fronted Amazon (Amazona aestiva, the Orange-winged Amazon (Amazona amazonica, and the Festive Amazon (Amazona festiva -, and provides useful data for the evaluation of their genetic variability. We electrophoretically analyzed blood samples from 68 wild-caught individuals, maintained in captivity in three Brazilian zoos. Eight of the ten studied enzyme loci exhibited polymorphism. Glucosephosphate isomerase (Gpi proved to be a diagnostic locus for the identification of these Amazon species. The expected average heterozygosity of the Blue-fronted Amazon (0.060 differed significantly from the expected heterozygosities of the Orange-winged Amazon and the Festive Amazon (0.040 and 0.039, respectively. This result was discussed as a consequence of hybridization between two geographic A. aestiva subspecies, and alternatively as a particular trait of this species. Genetic variability of the Blue-fronted Amazon compared to birds in general is not low on a species-wide level, despite the fact that this parrot is one of the most illegally traded species. Allozyme analysis proved to be an useful tool in monitoring the genetic variation within the genus Amazona and can be applied in the management program of other threatened species of this genus.

  3. Genetic variability in three Amazon parrot species.

    Science.gov (United States)

    Lopes, I F; Del Lama, M A; Del Lama, S N

    2007-12-01

    Parrots of the genus Amazona are among the most threatened species of the Order Pscittaciformes. This work describes allozyme polymorphisms in three Amazon parrot species--the Blue-fronted Amazon (Amazona aestiva), the Orange-winged Amazon (Amazona amazonica), and the Festive Amazon (Amazona festiva) -, and provides useful data for the evaluation of their genetic variability. We electrophoretically analyzed blood samples from 68 wild-caught individuals, maintained in captivity in three Brazilian zoos. Eight of the ten studied enzyme loci exhibited polymorphism. Glucosephosphate isomerase (Gpi) proved to be a diagnostic locus for the identification of these Amazon species. The expected average heterozygosity of the Blue-fronted Amazon (0.060) differed significantly from the expected heterozygosities of the Orange-winged Amazon and the Festive Amazon (0.040 and 0.039, respectively). This result was discussed as a consequence of hybridization between two geographic A. aestiva subspecies, and alternatively as a particular trait of this species. Genetic variability of the Blue-fronted Amazon compared to birds in general is not low on a species-wide level, despite the fact that this parrot is one of the most illegally traded species. Allozyme analysis proved to be an useful tool in monitoring the genetic variation within the genus Amazona and can be applied in the management program of other threatened species of this genus.

  4. How variation between individuals affects species coexistence.

    Science.gov (United States)

    Hart, Simon P; Schreiber, Sebastian J; Levine, Jonathan M

    2016-08-01

    Although the effects of variation between individuals within species are traditionally ignored in studies of species coexistence, the magnitude of intraspecific variation in nature is forcing ecologists to reconsider. Compelling intuitive arguments suggest that individual variation may provide a previously unrecognised route to diversity maintenance by blurring species-level competitive differences or substituting for species-level niche differences. These arguments, which are motivating a large body of empirical work, have rarely been evaluated with quantitative theory. Here we incorporate intraspecific variation into a common model of competition and identify three pathways by which this variation affects coexistence: (1) changes in competitive dynamics because of nonlinear averaging, (2) changes in species' mean interaction strengths because of variation in underlying traits (also via nonlinear averaging) and (3) effects on stochastic demography. As a consequence of the first two mechanisms, we find that intraspecific variation in competitive ability increases the dominance of superior competitors, and intraspecific niche variation reduces species-level niche differentiation, both of which make coexistence more difficult. In addition, individual variation can exacerbate the effects of demographic stochasticity, and this further destabilises coexistence. Our work provides a theoretical foundation for emerging empirical interests in the effects of intraspecific variation on species diversity. © 2016 John Wiley & Sons Ltd/CNRS.

  5. Species coexistence in a changing world

    Science.gov (United States)

    Valladares, Fernando; Bastias, Cristina C.; Godoy, Oscar; Granda, Elena; Escudero, Adrián

    2015-01-01

    The consequences of global change for the maintenance of species diversity will depend on the sum of each species responses to the environment and on the interactions among them. A wide ecological literature supports that these species-specific responses can arise from factors related to life strategies, evolutionary history and intraspecific variation, and also from environmental variation in space and time. In the light of recent advances from coexistence theory combined with mechanistic explanations of diversity maintenance, we discuss how global change drivers can influence species coexistence. We revise the importance of both competition and facilitation for understanding coexistence in different ecosystems, address the influence of phylogenetic relatedness, functional traits, phenotypic plasticity and intraspecific variability, and discuss lessons learnt from invasion ecology. While most previous studies have focused their efforts on disentangling the mechanisms that maintain the biological diversity in species-rich ecosystems such as tropical forests, grasslands and coral reefs, we argue that much can be learnt from pauci-specific communities where functional variability within each species, together with demographic and stochastic processes becomes key to understand species interactions and eventually community responses to global change. PMID:26528323

  6. Energetic Constraints on Species Coexistence in Birds.

    Science.gov (United States)

    Pigot, Alexander L; Tobias, Joseph A; Jetz, Walter

    2016-03-01

    The association between species richness and ecosystem energy availability is one of the major geographic trends in biodiversity. It is often explained in terms of energetic constraints, such that coexistence among competing species is limited in low productivity environments. However, it has proven challenging to reject alternative views, including the null hypothesis that species richness has simply had more time to accumulate in productive regions, and thus the role of energetic constraints in limiting coexistence remains largely unknown. We use the phylogenetic relationships and geographic ranges of sister species (pairs of lineages who are each other's closest extant relatives) to examine the association between energy availability and coexistence across an entire vertebrate class (Aves). We show that the incidence of coexistence among sister species increases with overall species richness and is elevated in more productive ecosystems, even when accounting for differences in the evolutionary time available for coexistence to occur. Our results indicate that energy availability promotes species coexistence in closely related lineages, providing a key step toward a more mechanistic understanding of the productivity-richness relationship underlying global gradients in biodiversity.

  7. Cryptic species as a window into the paradigm shift of the species concept.

    Science.gov (United States)

    Fišer, Cene; Robinson, Christopher T; Malard, Florian

    2018-02-01

    The species concept is the cornerstone of biodiversity science, and any paradigm shift in the delimitation of species affects many research fields. Many biologists now are embracing a new "species" paradigm as separately evolving populations using different delimitation criteria. Individual criteria can emerge during different periods of speciation; some may never evolve. As such, a paradigm shift in the species concept relates to this inherent heterogeneity in the speciation process and species category-which is fundamentally overlooked in biodiversity research. Cryptic species fall within this paradigm shift: they are continuously being reported from diverse animal phyla but are poorly considered in current tests of ecological and evolutionary theory. The aim of this review is to integrate cryptic species in biodiversity science. In the first section, we address that the absence of morphological diversification is an evolutionary phenomenon, a "process" counterpart to the long-studied mechanisms of morphological diversification. In the next section regarding taxonomy, we show that molecular delimitation of cryptic species is heavily biased towards distance-based methods. We also stress the importance of formally naming of cryptic species for better integration into research fields that use species as units of analysis. Finally, we show that incorporating cryptic species leads to novel insights regarding biodiversity patterns and processes, including large-scale biodiversity assessments, geographic variation in species distribution and species coexistence. It is time for incorporating multicriteria species approaches aiming to understand speciation across space and taxa, thus allowing integration into biodiversity conservation while accommodating for species uncertainty. © 2018 John Wiley & Sons Ltd.

  8. Economics of Harmful Invasive Species: A Review

    Directory of Open Access Journals (Sweden)

    George Marbuah

    2014-07-01

    Full Text Available The purpose of this study is to review theoretical and empirical findings in economics with respect to the challenging question of how to manage invasive species. The review revealed a relatively large body of literature on the assessment of damage costs of invasive species; single species and groups of species at different geographical scales. However, the estimated damage costs show large variation, from less than 1 million USD to costs corresponding to 12% of gross domestic product, depending on the methods employed, geographical scale, and scope with respect to inclusion of different species. Decisions regarding optimal management strategies, when to act in the invasion chain and which policy to choose, have received much less attention in earlier years, but have been subject to increasing research during the last decade. More difficult, but also more relevant policy issues have been raised, which concern the targeting in time and space of strategies under conditions of uncertainty. In particular, the weighting of costs and benefits from early detection and mitigation against the uncertain avoidance of damage with later control, when the precision in targeting species is typically greater is identified as a key challenge. The role of improved monitoring for detecting species and their spread and damage has been emphasized, but questions remain on how to achieve this in practice. This is in contrast to the relatively large body of literature on policies for mitigating dispersal by trade, which is regarded as one of the most important vectors for the spread of invasive species. On the other hand, the literature on how to mitigate established species, by control or adaptation, is much more scant. Studies evaluating causes for success or failure of policies against invasive in practice are in principal non-existing.

  9. Review: Allee effects in social species.

    Science.gov (United States)

    Angulo, Elena; Luque, Gloria M; Gregory, Stephen D; Wenzel, John W; Bessa-Gomes, Carmen; Berec, Ludek; Courchamp, Franck

    2018-01-01

    Allee effects have important implications for many aspects of basic and applied ecology. The benefits of aggregation of conspecific individuals are central to Allee effects, which have led to the widely held assumption that social species are more prone to Allee effects. Robust evidence for this assumption, however, remains rare. Furthermore, previous research on Allee effects has failed to adequately address the consequences of the different levels of organisation within social species' populations. Here, we review available evidence of Allee effects and model the role of demographic and behavioural factors that may combine to dampen or strengthen Allee effects in social species. We use examples across various species with contrasting social structure, including carnivores, bats, primates and eusocial insects. Building on this, we provide a conceptual framework that allows for the integration of different Allee effects in social species. Social species are characterised by nested levels of organisation. The benefits of cooperation, measured by mean individual fitness, can be observed at both the population and group levels, giving rise to "population level" and "group level" Allee effects respectively. We also speculate on the possibility of a third level, reporting per capita benefits for different individuals within a group (e.g. castes in social insects). We show that group size heterogeneity and intergroup interactions affect the strength of population-level demographic Allee effects. Populations with higher group size heterogeneity and in which individual social groups cooperate demonstrate the weakest Allee effects and may thus provide an explanation for why extinctions due to Allee effects are rare in social species. More adequately accounting for Allee effects in social species will improve our understanding of the ecological and evolutionary implications of cooperation in social species. © 2017 The Authors. Journal of Animal Ecology © 2017 British

  10. Single species victory in a two-site, two-species model of population dispersion

    Science.gov (United States)

    Waddell, Jack; Sander, Len; Kessler, David

    2008-03-01

    We study the behavior of two species, differentiated only by their dispersal rates in an environment providing heterogeneous growth rates. Previous deterministic studies have shown that the slower-dispersal species always drives the faster species to extinction, while stochastic studies show that the opposite case can occur given small enough population and spatial heterogeneity. Other models of similar systems demonstrate the existence of an optimum dispersal rate, suggesting that distinguishing the species as faster or slower is insufficient. We here study the interface of these models for a small spatial system and determine the conditions of stability for a single species outcome.

  11. Dna c-values of 20 invasive alien species and 3 native species in south china

    Directory of Open Access Journals (Sweden)

    Gong Ni

    2014-01-01

    Full Text Available Cultivated fields and forests in South China are experiencing serious damage due to invasive alien plants. We investigated the relation between DNA C-values and invasiveness. The DNA C-values of 23 species ranged from 0.39 pg to 3.37 pg. Herbs, perennials and native species had higher mean DNA C-values than shrubs, annuals and invasive alien species. DNA C-values decreased with increasing invasiveness. Paederia scandens, a harmful native species, has the lowest DNA C-value among the perennials, indicating that native species with low nuclear content may also possess an invasive potential.

  12. How many species of giraffe are there?

    Science.gov (United States)

    Bercovitch, Fred B; Berry, Philip S M; Dagg, Anne; Deacon, Francois; Doherty, John B; Lee, Derek E; Mineur, Frédéric; Muller, Zoe; Ogden, Rob; Seymour, Russell; Shorrocks, Bryan; Tutchings, Andy

    2017-02-20

    In a recent paper in Current Biology, Fennessy and colleagues [1] conclude that there are four species of giraffe and that their numbers are declining in Africa. Giraffes (Giraffa camelopardalis) are presently classified as one species, with nine subspecies, which are considered 'Vulnerable' on the IUCN Red List [2]. The present consensus of one species divided into nine subspecies has previously been questioned (Supplemental information), and Fennessy and colleagues [1] provide another viewpoint on giraffe taxonomy. The fundamental reason for different taxonomic interpretations is that they are based upon different datasets that adopt different statistical techniques and follow different criteria for nomenclature. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Fort Collins Science Center: Invasive Species Science

    Science.gov (United States)

    Stohlgren, Tom

    2004-01-01

    Invasive, non-native species of plants, animals, and disease organisms adversely affect the ecosystems they enter. Like "biological wildfires," they can quickly spread, and they affect nearly all terrestrial and aquatic ecosystems. Invasive species have become the greatest environmental challenge of the 21st century in terms of economic, environmental, and human health costs, with an estimated impact in the U.S. of over $138 billion per year. Managers of Department of the Interior and other public and private lands and waters rank invasive species as their top resource management problem.

  14. Reservoirs of Non-baumannii Acinetobacter Species

    Science.gov (United States)

    Al Atrouni, Ahmad; Joly-Guillou, Marie-Laure; Hamze, Monzer; Kempf, Marie

    2016-01-01

    Acinetobacter spp. are ubiquitous gram negative and non-fermenting coccobacilli that have the ability to occupy several ecological niches including environment, animals and human. Among the different species, Acinetobacter baumannii has evolved as global pathogen causing wide range of infection. Since the implementation of molecular techniques, the habitat and the role of non-baumannii Acinetobacter in human infection have been elucidated. In addition, several new species have been described. In the present review, we summarize the recent data about the natural reservoir of non-baumannii Acinetobacter including the novel species that have been described for the first time from environmental sources and reported during the last years. PMID:26870013

  15. Automatic identification of species with neural networks

    Directory of Open Access Journals (Sweden)

    Andrés Hernández-Serna

    2014-11-01

    Full Text Available A new automatic identification system using photographic images has been designed to recognize fish, plant, and butterfly species from Europe and South America. The automatic classification system integrates multiple image processing tools to extract the geometry, morphology, and texture of the images. Artificial neural networks (ANNs were used as the pattern recognition method. We tested a data set that included 740 species and 11,198 individuals. Our results show that the system performed with high accuracy, reaching 91.65% of true positive fish identifications, 92.87% of plants and 93.25% of butterflies. Our results highlight how the neural networks are complementary to species identification.

  16. [Applied fundamental research of echinacea species].

    Science.gov (United States)

    Zhang, Ying-Tao; Wang, Hong; Liu, Wen-Zhi; Tong, Wei; Yang, Yan-Fang; Ai, Tie-Min

    2004-02-01

    Echinacea is a most famous "immune herb" in western countries, and continues to be the best selling herb for many years. For the last five years, our research group has cooperated with Institute of Medicinal Plants in Huairou District of Beijing, carrying out studies on Echinacea purpurea, which involved botany, cultivation, pharmacognosy, phytochemistry, quality control, pharmacology and toxicology of the species. Two other species introduced from Canada, Echinacea angustifolia and Echinacea pallida, were also included in the taxonomic, cultivated and pharmacognostic studies. The results acquired have opened up the path to introduce Echinacea species into Traditional Chinese Medicine, thus established the possibility of developing more promising drugs from them.

  17. An updated checklist of mosquito species (Diptera: Culicidae from Madagascar

    Directory of Open Access Journals (Sweden)

    Tantely Michaël Luciano

    2016-01-01

    Full Text Available An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species. This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species, Aedes (35 species, Anopheles (26 species, Coquillettidia (3 species, Culex (at least 50 species, Eretmapodites (4 species, Ficalbia (2 species, Hodgesia (at least one species, Lutzia (one species, Mansonia (2 species, Mimomyia (22 species, Orthopodomyia (8 species, Toxorhynchites (6 species, and Uranotaenia (73 species. Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%. Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27% with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar.

  18. An updated checklist of mosquito species (Diptera: Culicidae) from Madagascar

    Science.gov (United States)

    Tantely, Michaël Luciano; Le Goff, Gilbert; Boyer, Sébastien; Fontenille, Didier

    2016-01-01

    An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species). This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species), Aedes (35 species), Anopheles (26 species), Coquillettidia (3 species), Culex (at least 50 species), Eretmapodites (4 species), Ficalbia (2 species), Hodgesia (at least one species), Lutzia (one species), Mansonia (2 species), Mimomyia (22 species), Orthopodomyia (8 species), Toxorhynchites (6 species), and Uranotaenia (73 species). Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%). Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27%) with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar. PMID:27101839

  19. An updated checklist of mosquito species (Diptera: Culicidae) from Madagascar.

    Science.gov (United States)

    Tantely, Michaël Luciano; Le Goff, Gilbert; Boyer, Sébastien; Fontenille, Didier

    2016-01-01

    An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species). This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species), Aedes (35 species), Anopheles (26 species), Coquillettidia (3 species), Culex (at least 50 species), Eretmapodites (4 species), Ficalbia (2 species), Hodgesia (at least one species), Lutzia (one species), Mansonia (2 species), Mimomyia (22 species), Orthopodomyia (8 species), Toxorhynchites (6 species), and Uranotaenia (73 species). Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%). Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27%) with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar. © M.L. Tantely et al., published by EDP Sciences, 2016.

  20. The green seaweed Ulva: A model system to study morphogenesis

    OpenAIRE

    Thomas eWichard; Benedicte eCharrier; Benedicte eCharrier; Frédéric eMineur; John Henry Bothwell; Olivier eDe Clerck; Juliet C. Coates

    2015-01-01

    Green macroalgae, mostly represented by the Ulvophyceae, the main multicellular branch of the Chlorophyceae, constitute important primary producers of marine and brackish coastal ecosystems. Ulva or sea lettuce species are some of the most abundant representatives, being ubiquitous in coastal benthic communities around the world. Nonetheless the genus also remains largely understudied. This review highlights Ulva as an exciting novel model organism for studies of algal growth, development and...