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Sample records for cirripedia rhizocephala sacculinidae

  1. Sympatric three-species infection by Sacculina parasites (Cirripedia: Rhizocephala: Sacculinidae) of an intertidal grapsoid crab

    DEFF Research Database (Denmark)

    Tsuchida, Kohei; Lützen, Jørgen; Nishida, Mutsumi

    2006-01-01

    Parasitization by sacculinids (Cirripedia: Rhizocephala: Sacculinidae) induces severe modifications in morphology, behavior, and reproduction of their host crabs. To understand the mechanisms involved, it is important to have comprehensive information on their association. However, such information...... of Sacculina, S. confragosa, S. imberbis, and S. yatsui, were found to parasitize a single host crab, Pachygrapsus crassipes, sympatrically in a restricted area. This is the first finding for three-on-one association in a single locality....

  2. Phylogeny and evolution of life history strategies of the Parasitic Barnacles (Crustacea, Cirripedia, Rhizocephala)

    DEFF Research Database (Denmark)

    Glenner, Henrik; Hebsgaard, Martin Bay

    2006-01-01

    The barnacles (Crustacea, Cirripedia) consist of three well-defined orders: the conventional filter-feeding barnacles (Thoracica), the burrowing barnacles (Acrothoracica), and the parasitic barnacles (Rhizocephala). Thoracica and Acrothoracica feed by catching food particles from the surrounding...... to resolve the phylogenetic relationship of the order Rhizocephala and elucidate the evolution of the different life history strategies found within the Rhizocephala, we have performed the first comprehensive phylogenetic analysis of the group. Our results indicate that Rhizocephala is monophyletic...

  3. Cypris metamorphosis, injection and earliest internal development of theRrizocephalan Loxothylacus panopaei (Gissler). Crustacea: Cirripedia: Rhizocephala: Sacculinidae

    DEFF Research Database (Denmark)

    Glenner, H

    2001-01-01

    , and the succeeding developmental stages up to the stage of the earliest primordium reported from the literature. The anlage of the ovary is traced back to the free-swimming cypris stage and it is implied that the mesoderm and ectoderm of the endoparasite are already differentiated in the cyprid....

  4. Sacculina nectocarcini, a new species of rhizocephalan, a new species of rhizocephalan(Cirripedia: Rhizocephala) parasitising the red rock crabNectocarcinus integrifrons (Decapoda: Brachyura: Portunidae)(Decapoda: Brachyura: Portunidae)

    DEFF Research Database (Denmark)

    Gurney, Robert H.; Rybakov, Alexey V.; Høeg, Jens Thorvald;

    2006-01-01

    The parasitic barnacles, Rhizocephala, are a little known group within Australia with only seven described species from a coastline stretching approximately 59763 km. This study describes a new species of Rhizocephala, Sacculina nectocarcini. The description is based on a unique combination...

  5. Why Williamson's (2014) theory of Hybridogenesis fails to explain the evolution of the Rhizocephala

    DEFF Research Database (Denmark)

    Glenner, Henrik; Lytzen, Jørgen Gjerom

    2015-01-01

    Alle biologiske, ultrastrukturelle og molekylære data understøtter konlusionen at subordernerne Cirripedia, Rhizocephala og Thoracica er nært beslægtede. Williamsons spekulationer, nemlig at den såkaldte hybridogenesis kan forklare hvo ledes Rhizocepahlerne har udviklet sig, hviler på et selektiv...

  6. A Study of the Morphology and Biology of Thompsonia littoralis (Crustacea: Cirripedia: Rhizocephala)

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Jespersen, Åse

    1992-01-01

    of the thoracic appendages. As many externae drop off, their number is continuously reduced; the survivors reach sexual maturity and ovulate after 2.5 months and complete embryonic development after 2 more months. At the next moult a new and more numerous generation of externae appears, and this is repeated until...

  7. The unusual floatation collar around nauplii of certain parasitic barnacles (Crustacea: Cirripedia: Rhizocephala)

    DEFF Research Database (Denmark)

    Høeg, Jens Thorvald; Møller, Ole Sten; Rybakov, Alexey V.

    2004-01-01

    microscopy shows that the collar of the succeeding nauplius instar is formed in an unexpanded state beneath the old cuticle and it must therefore be inflated at or immediately after ecdysis. At ecdysis the collar of the old instar breaks along the attachment ridge, leaving the empty collar and the exuvium...

  8. First Record on Larval Development of the Cirripedian Parasite Loxothylacus texanus (Cirripedia-Rhizocephala Under Laboratory Conditions in Mxico

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    J. Franco-Lopez

    2006-01-01

    Full Text Available Crabs with mature parasites were put on individual aquariums of 20 L of capacity and with an initial salinity of 10. Salinity was gradually increased 1 until it reached a point in which parasites expeled their eggs or larvae. Larvae at different developmental stages obtained from each sample were preserved in 70 and ethanol to be studied afterwards. From 20 crabs employed, only 14 of them produced eggs and other 6 died after a few days at the aquariums. The mature externas expelled from 8000 to 160000 clustered eggs. After 24 h from the beginning of cellular division, larvae hatch. This larvae are called nauplius 1. This stage lasted 24 h, after which all larvae entered an excitation period, where they rapidly moved, to then pass a new molt process resulting in a new larval stage, nauplius 2. Elevating salinity a unity, externas started to expel eggs, nauplis larvae 1 hatched from them, but they only survived less than 24 h. As salinity increased, nauplius larvae lived longer, even to realized a molt. At a 15 salinity, larvae reached cypris stage with no problem, but with a salinity higher than 25, larvae died after a few hours of hatching. We can conclude that: the rhizocephalan Loxothylacus texanus has two nauplius stages, the nauplius and cypris larvae presented similar morphological characteristics to related species of rhizocephalans and a salinity interval from 15 to 20 report the same result.

  9. Cypris morphology in the barnacles Ibla and Paralepas (Crustacea: Cirripedia Thoracica) implications for cirripede evolution

    DEFF Research Database (Denmark)

    Høeg, Jens T; Achituv, Yair; Chan, Benny K K;

    2009-01-01

    are of the pore-field type and the terminal pore is situated anteriorly in the first pair, just as in the Rhizocephala and the Thoracica. In Ibla the armament of antennular sensilla resembles that found in the Thoracica but differs from the Rhizocephala. The absence of setules on the A and B setae sited...

  10. Over de eerste vondsten van twee Pennella-soorten (Crustacea: Copepoda) en van Conchoderma virgatum (Spengler) (Crustacea: Cirripedia) in Nederland

    NARCIS (Netherlands)

    Huwae, P.H.M.

    1986-01-01

    On 30 November 1941 a sunfish Mola mola (L.) was found on the beach near Schoorl (Province of Noord-Holland). The fish was parasitized by a specimen of Pennella filosa (L.) (Crustacea, Copepoda) on which a specimen of Conchoderma virgatum (Crustacea: Cirripedia) had attached itself. This is the firs

  11. Comparison of nutritional status of field and laboratory reared Balanus amphitrite Darwin (Cirripedia: Thoracica) larvae and implication of starvation

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, D.V.; Anil, A.C.

    Comparison of nutritional status of field and laboratory reared Balanus amphitrite Darwin (Cirripedia: Thoracica) larvae and implication of starvation Dattesh V. Desai, A.C. Anil * Marine Corrosion and Materials Research Division, National Institute... (Thorson, 1950; Crisp, 1976; Olson and Olson, 1989; Anil et al., 1995). Starvation will lead to nutritional stress, which can kill the larvae directly or may increase or decrease the duration of larval developmental stages (Knowlton, 1974; Sandifer...

  12. A coral-eating barnacle, revisited (Cirripedia, Pyrgomatidae)

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    Ross, Arnold; Newman, William A.

    1995-01-01

    The coral-eating barnacle Hoekia monticulariae (Gray, 1831), the only internal parasite among the Thoracica described to this day, is characterized by an irregularly-shaped shell nestled cryptically between the polyps of the hermatypic coral Hydnophora Fischer, 1807, which occurs throughout most of

  13. Studies on some ecological aspects of Balanus amphitrite (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, D.V.

    The year round breeding capability of Balanus amphitrite indicates a potential for continuous recruitment. The recruitment pattern however indicated a lull during monsoon. The study site experiences increased land run off lowering the salinity...

  14. Sacculina beauforti and Loxothylacus ihlei, two Rhizocephala of the Crab Scylla serata (Forsk.)

    NARCIS (Netherlands)

    Boschma, H.

    1949-01-01

    With great pleasure I dedicate the two new species described below to the two Amsterdam zoologists Prof. L. F. DE BEAUFORT and Prof. J. E. W. IHLE, who with their important researches in various branches of zoology both have so largely contributed to the progress of this science. The two species des

  15. On a New Species of Parasitic Barnacle (Crustacea: Rhizocephala), Sacculina shiinoi sp. nov., Parasitizing Japanese Mud Shrimps Upogebia spp. (Decapoda: Thalassinidea: Upogebiidae), Including a Description of a Novel Morphological Structure in the Rhizocephala.

    Science.gov (United States)

    Lützen, Jørgen; Itani, Gyo; Jespersen, Åse; Hong, Jae-Sang; Rees, David; Glenner, Henrik

    2016-04-01

    The rhizocephalan Sacculina shiinoi sp. nov. parasitizes three species of Upogebia in Japan. It is described morphologically and compared with another Upogebia parasite, Sacculina upogebiae Shiino, 1943 from Japan and Korea. These two species are the only sacculinids that parasitize mud shrimps. DNA analyses clearly show the two species to be separate and not closely related. The cuticle differs in being provided with close-set, branched, and spiny excrescences in S. shiinoi, while it lacks excrescences, but forms small scales in S. upogebiae. In S. upogebiae, the bulbous sperm-producing part and the narrow receptacle duct are separated by a compartmentalized mid portion, which is missing in S. shiinoi. A ridge, having a thickened, fluffy cuticle with a U-shaped course, passes across the visceral mass between the two receptacle openings in S. shiinoi. Such a structure has never been described in other rhizocephalans, and its function is uncertain. PMID:27032686

  16. Biological features on epibiosis of Amphibalanus improvisus (Cirripedia on Macrobrachium acanthurus (Decapoda

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    Cristiane Maria Rocha Farrapeira

    2010-06-01

    Full Text Available This study aimed to describe the epibiosis of barnacles Amphibalanus improvisus on eight adult Macrobrachium acanthurus males from the Mundaú Lagoon, state of Alagoas, Brazil. The number of epibiont barnacles varied from 247 to 1,544 specimens per prawn; these were distributed predominantly on the cephalothorax and pereiopods, but also on the abdomen and other appendices. Although some were already reproducing, most barnacles had been recruited recently or were still sexually immature; this suggests recent host arrival in that estuarine environment. Despite the fact that other barnacles occur in this region, A. improvisus is the only species reported as an epibiont on Macrobrachium acanthurus; this was also the first record of epibiosis on this host. The occurrence of innumerable specimens in the pereiopods' articulations and the almost complete covering of the carapace of some prawns (which also increased their weight suggest that A. improvisus is adapted to fixate this kind of biogenic substrate and that the relationship between the two species biologically damages the basibiont.O objetivo deste trabalho foi relatar a epibiose de cirrípedes Amphibalanus improvisus em oito camarões machos adultos da espécie Macrobrachium acanthurus provenientes da Laguna Mundaú, Alagoas, Brasil. O número de cirrípedes epibiontes variou desde 247 até 1.544 espécimes por camarão, distribuídos predominantemente no cefalotórax e pereiópodos, mas presentes também no abdome e demais apêndices. A grande maioria dos cirrípedes era recém-recrutada ou ainda estava sexualmente imatura, embora de alguns estivessem já em reprodução, sugerindo a chegada recente de seu hospedeiro no ambiente estuarino. Apesar de ocorrem outros cirrípedes na região, A. improvisus foi à única espécie relatada como epibionte em Macrobrachium acanthurus e isto se constituiu o primeiro registro de epibiose de Amphibalanus improvisus A ocorrência de inúmeros espécimes nas articulações dos pereiópodos e o recobrimento quase total da carapaça de alguns camarões (incrementando peso aos mesmos indicam que a espécie epibionte está adaptada à fixação neste substrato biogênico e que a relação entre estas duas espécies traz prejuízos biológicos ao basibionte.

  17. Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia).

    Science.gov (United States)

    Chan, Benny K K; Chen, H-N; Dando, P R; Southward, A J; Southward, E C

    2016-01-01

    The biogeography and ecology of the species of Chthamalus present on the west coast of America are described, using data from 51 localities from Alaska to Panama, together with their zonation on the shore with respect to that of other barnacles. The species present were C. dalli, Pilsbry 1916, C. fissus, Darwin, 1854, C. anisopoma Pilsbry 1916 and four species in the C. panamensis complex. The latter are C. panamensis Pilsbry, 1916, C. hedgecocki, Pitombo & Burton, 2007, C. alani nom. nov. (formerly C. southwardorum Pitombo & Burton, 2007) and C. newmani sp. nov.). These four species were initially separated by enzyme electrophoresis. They could only be partially separated by DNA bar coding but may be separated using morphological characters.

  18. Exploration and metamorphosis in Balanus amphitrite Darwin (Cirripedia ; Thoracica) cyprids: significance of sugars and adult extract

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; Anil, A.C.; Raghukumar, S.

    footprints when exposed to multiwells coated with AE. A comparison of observations between single cyprid and multiple cyprid assays showed a similar trend, thus indicating that larva-larva interaction may not play an important role, when such pretreated...

  19. Physiological responses to hypoxia and anoxia in Balanus amphitrite (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, D.V.; Prakash, S.

    (hypoxia) and no oxygen (anoxia) on B. amphitrite adults and nauplii was assessed. Their response was evaluated by estimating the levels of the antioxidant enzymes catalase and superoxide dismutase. The impact of desiccation on antioxidant enzymes in adult...

  20. Studies on some cues regulating metamorphosis of the larvae of Balanus amphitrite (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.

    suitable place to settle. The cyprid footprints have also been reported to induce settlement of other cyprids, even in the absence of conspecific adults (Walker and Yule 1984; Yule and Walker 1985; Clare et al. 1994). Chemical cues such as bacterial... of bacterial exopolysaccharides from both marine and freshwater environments (Sutherland 1980). The interactions between bacterial exopolymers and cypris temporary adhesive are most likely to be effected via polar groups. The strength of these interactions...

  1. Significance of biofilm proteins in modulating cyprid metamorphosis of Balanus amphitrite (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; KrishnaKumar, S.

    address:klidita@nio.org (Lidita Khandeparker) 2 Problem Biofouling is a prominent feature on artificial structures like ship hulls, underwater pipelines, bridges, offshore platforms etc. that results in their modification leading...

  2. Reproduction in Balanus amphitrite Darwin (Cirripedia: Thoracica); influence of temperature and food concentration

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, D.V.; Anil, A.C.; Venkat, K.

    the numbers of larvae released vs. the number of days (experimental schedule) for which the barnacles were raised indicated that the number of larvae released increased with the age of the barnacles. This increase was significant in case the of barnacles...

  3. Molecular phylogeny and character evolution of the chthamaloid barnacles (Cirripedia:Thoracica)

    DEFF Research Database (Denmark)

    Pérez-Losada, Marcos; Høeg, Jens Thorvald; Crandall, Keith A.;

    2012-01-01

    of the Chthamaloidea has been debated since Darwin's seminal monographs. Theories of morphological and ontogenetic evolution suggest that the group could have evolved multiple times from pedunculated relatives and that shell plate number diminished gradually (8¿6¿4) from an ancestral state with eight wall plates......The Chthamaloidea (Balanomorpha) present the most plesiomorphic characters in shell plates and cirri, mouthparts, and oral cone within the acorn barnacles (Thoracica: Sessilia). Due to their importance in understanding both the origin and diversification of the Balanomorpha, the evolution...... surrounded by whorls of small imbricating plates; but this hypothesis has never been subjected to a rigorous phylogenetic test. Here we used multilocus sequence data and extensive taxon sampling to build a comprehensive phylogeny of the Chthamaloidea as a basis for understanding their morphological evolution...

  4. Phylogenetic position and evolutionary history of the turtle and whale barnacles (Cirripedia: Balanomorpha: Coronuloidea).

    Science.gov (United States)

    Hayashi, Ryota; Chan, Benny K K; Simon-Blecher, Noa; Watanabe, Hiromi; Guy-Haim, Tamar; Yonezawa, Takahiro; Levy, Yaniv; Shuto, Takuho; Achituv, Yair

    2013-04-01

    Barnacles of the superfamily Coronuloidea are obligate epibionts of various marine mammals, marine reptiles and large crustaceans. We used five molecular markers: 12S rDNA, 16S rDNA, 18S rDNA, 28S rDNA and Histone 3 to infer phylogenetic relationships among sixteen coronuloids, representing most of the recent genera of barnacles of this superfamily. Our analyses confirm the monophyly of Coronuloidea and that this superfamily and Tetraclitoidea are sister groups. The six-plated Austrobalanus clusters with these two superfamilies. Based on BEAST and ML trees, Austrobalanus is basal and sister to the Coronuloidea, but the NJ tree places Austrobalanus within the Tetraclitoidae, and in the MP tree it is sister to both Coronuloidea and Tetraclitoidae. Hence the position of Austrobalanus remains unresolved. Within the Coronuloidea we identified four clades. Chelonibia occupies a basal position within the Coronuloidea which is in agreement with previous studies. The grouping of the other clades does not conform to previous studies. Divergence time analyses show that some of the time estimates are congruent with the fossil record while some others are older, suggesting the possibility of gaps in the fossil record. PMID:23306306

  5. Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia.

    Directory of Open Access Journals (Sweden)

    Benny K K Chan

    Full Text Available The biogeography and ecology of the species of Chthamalus present on the west coast of America are described, using data from 51 localities from Alaska to Panama, together with their zonation on the shore with respect to that of other barnacles. The species present were C. dalli, Pilsbry 1916, C. fissus, Darwin, 1854, C. anisopoma Pilsbry 1916 and four species in the C. panamensis complex. The latter are C. panamensis Pilsbry, 1916, C. hedgecocki, Pitombo & Burton, 2007, C. alani nom. nov. (formerly C. southwardorum Pitombo & Burton, 2007 and C. newmani sp. nov.. These four species were initially separated by enzyme electrophoresis. They could only be partially separated by DNA bar coding but may be separated using morphological characters.

  6. Influence of temperature on the starvation threshold of nauplii of barnacle Balanus amphitrite (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, D.V.; Anil, A.C

    An evaluation of starvation threshold of the newly hatched Balanus amphitrite nauplii (instar, II) has been made at three different temperatures (5, 15 and 25°C). Earlier studies on starvation in crustacean larvae demonstrated Point of No Return...

  7. Growth and molting in epizoic pedunculate barnacles genus Octolasmis (Crustacea: Thecostraca: Cirripedia: Thoracica)

    DEFF Research Database (Denmark)

    Blomsterberg, Mikkel; Glenner, Henrik; Høeg, Jens T

    2004-01-01

    layers is entirely restricted to the growth zones. Just prior to ecdysis, the new cuticle lies in a highly folded fashion beneath the old cuticle that is about to be shed. At ecdysis, the old cuticle breaks along the margins of the growth zones and the resulting scars remain as a system of "ecdysial...... that size increase is due to the formation of new cuticle by molting in the growth zones, while expansion of the shell plates by mineralization follows only after production of the new cuticle. Thus, although specialized, growth in Octolasmis still complies with the general crustacean model, complicated...

  8. Notes on the ultrastructure of the setae on the fourth antennulary segment of the Balanus amphitrite cyprid (Crustacea : Cirripedia : Thoracica)

    DEFF Research Database (Denmark)

    Lagersson, Niklas; Garm, Anders Lydik; Høeg, Jens Thorvald

    2003-01-01

    while one seta (sE) is presumed to be a unimodal mechanoreceptor. We suggest that setae A and B are stimulated by the water flow, seta D is olfactory, seta E detects the topography of the substratum by touch, and the subterminal setae are touch chemoreceptors. No function is suggested for seta C....

  9. Influence of bacterial exopolymers, conspecific adult extract and salinity on the cyprid metamorphosis of Balanus amphitrite (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Anil, A.C.; Khandeparker, R.

    The influence of bacterial exopolymers and conspecific adult extract of Balanus amphitrite on metamorphosis of cyprid larvae at different salinities has been evaluated through laboratory assay. The bacterial exopolymers (epm) extracted from...

  10. The impact of food type, temperature and starvation on larval development of Balanus amphitrite Darwin (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, D.V.; Anil, A.C.

    The impact of diatom food species (Chaetoceros calcitrans and Skeletonema costatum), temperature and starvation on the larval development of Balanus amphitrite was evaluated. Starvation threshold levels for different ages of larvae (0- to 5-day...

  11. Larval development and metamorphosis in Balanus amphitrite Darwin (Cirripedia; Thoracica): Significance of food concentration, temperature and nucleic acids

    Digital Repository Service at National Institute of Oceanography (India)

    Anil, A.C.; Desai, D.V.; Khandeparker, L.

    barnacles to compete for space and seriously reduce their likelihood of successfully recruiting to the adult population. In Ž. Ž. the light of these observations, Jarrett and Pechenik 1997 and Pechenik et al. 1998 opined that larval experience influences... during the course of this work. We thank Dr. S.S. Sawant and Mr. K. Venkat Ž. and other colleagues of MCMRD for their help. The authors D.D and L.K greatly acknowledge CSIR, India for the award of Senior Research Fellowships. This work was Ž.[] supported...

  12. The whale barnacle Cryptolepas rhachianecti (Cirripedia: Coronulidae), a phoront of the grey whale Eschrichtius robustus (Cetacea: Eschrichtiidae), from a sandy beach in The Netherlands.

    Science.gov (United States)

    Bosselaers, Mark; Collareta, Alberto

    2016-08-22

    An isolated compartment of a whale barnacle is herein described from Recent beach deposits in Zoutelande (Walcheren, The Netherlands). This specimen is identified as belonging to the extant coronulid species Cryptolepas rhachianecti, currently known as an epizoic symbiont of the grey whale Eschrichtius robustus. This find represents the first occurrence of C. rhachianecti outside the North Pacific, and the first one as a (sub)fossil. In view of the fact that E. robustus, which is currently confined to the North Pacific, is known as a subfossil from the northeastern Atlantic between late Late Pleistocene (c. 45,000 years ago) and historical (c. 1700 AD) times, we propose a similar (late Quaternary) age for the isolated compartment. The find indicates that the extinct late Quaternary northeastern Atlantic population of E. robustus was infected by Cryptolepas rhachianecti. Our find is, therefore, compatible with the hypothesis of an ancient grey whale migration route running between the subtropical/temperate waters of the northeast Atlantic (or Mediterranean Basin), and the cold waters of the Baltic Sea (or southern Arctic Ocean), through the southern North Sea. Finally, we discuss the systematic placement of the fossil barnacle species Cryptolepas murata and propose the possibility of its removal from the genus Cryptolepas pending further investigations.

  13. Southern hemisphere deep-water stylasterid corals including a new species, Errina labrosa sp. n. (Cnidaria, Hydrozoa, Stylasteridae, with notes on some symbiotic scalpellids (Cirripedia, Thoracica, Scalpellidae

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    Daniela Pica

    2015-01-01

    Full Text Available A number of stylasterid corals are known to act as host species and create refuges for a variety of mobile and sessile organisms, which enhances their habitat complexity. These include annelids, anthozoans, cirripeds, copepods, cyanobacteria, echinoderms, gastropods, hydroids and sponges. Here we report the first evidence of a diverse association between stylasterids and scalpellid pedunculate barnacles and describe a new stylasterid species, Errina labrosa, from the Tristan da Cunha Archipelago. Overall, five stylasterid species are found to host eight scalpellid barnacles from several biogeographic regions in the southern hemisphere (Southern Ocean, temperate South America and the southern Indo-Pacific realms. There is an apparent lack of specificity in this kind of association and different grades of reaction to the symbiosis have been observed in the coral. These records suggest that the association between pedunculate barnacles and hard stylasterid corals has a wide distribution among different biogeographic realms and that it is relatively rare and confined largely to deep water.

  14. Three-dimensional computer-aided reconstruction of FMRFamide immunopositive neuron distribution in the ventral ganglion of the barnacle Balanus amphitrite (Cirripedia, Crustacea

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    L Gallus

    2009-12-01

    Full Text Available We have implemented a simple program to solve three of the problems related to 3D reconstruction (3D-Rec of soft tissues: alignment of sections, distortions, and estimation of the spatial position of elements of interest inside the tissues. As a model, we chose the distribution of FMRFamide-like immunopositive neurons in the ventral ganglion of the barnacle Balanus amphitrite collected during different seasonal periods. Images of immunostained sections were acquired by means of a CCDcamera- equipped microscope and a PC and the reference points were taken inside the sections. The FMRFamide-like immunopositive neurons detected in the barnacle ventral ganglion were grouped into four different classes according to size, shape and staining intensity. More numerous FMRFamide- like immunopositive neurons were detected in the autumn-collected barnacle than in the summer counterpart. The two 3D reconstructions obtained from transverse and longitudinal ventral ganglion sections were efficaciously compared after 90° rotation of one of them. Comparison of these two 3D-Rec suggests the presence of at least two groups of FMRFamide-like immunopositive neurons that are seasonally-related and probably involved in reproduction.

  15. Reproduction and larval development in three scalpellid barnacles, Scalpellum scalpellum (Linnaeus 1767), Ornatoscalpellum stroemii (M. Sars 1859) and Arcoscalpellum michelottianum (Seguenza 1876), Crustacea: Cirripedia: Thoracica): implications for reproduction

    DEFF Research Database (Denmark)

    Buhl-Mortensen, Lene; Høeg, Jens Thorvald

    2006-01-01

    than the other two species. We hypothesize that the observed differences in reproductive system and mode of development in the three species represent adaptations to their different habitats. S. scalpellum are mainly transported by currents in the coastal sublittoral zone. O. stroemii is presumably......We studied reproduction and larval development in three species of pedunculated barnacles with different depth distribution, that is, Scalpellum scalpellum (30-200 m), Ornatoscalpellum stroemii (100-1,600 m) and Arcoscalpellum michelottianum (64-5,190 m). Morphology, position and number of males...... in the female/hermaphrodite, type of larval development and the number and size of eggs were recorded. All three species have a pair of pocket-like receptacles, each of which can host only a single male in O. stroemii, up to five males in S. scalpellum and up to 12 males in A. michelottianum. Eggs and larvae...

  16. Antifouling effect of bioactive compounds from marine sponge Acanthella elongata and different species of bacterial film on larval attachment of Balanus amphitrite (cirripedia, crustacea

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    Viswambaran Ganapiriya

    2012-06-01

    Full Text Available The antifouling activity of bioactive compounds from marine sponge Acanthella elongata (Dendy and five species of bacterial biofilm were studied. Larvae of Balanus amphitrite (Cyprids and nauplii were used to monitor the settlement inhibition and the extent to which inhibition was due to toxicity. The crude extract and partially purified fractions of A.elongata showed significant inhibition over the settlement individually, and with the interaction of bacterial species. No bacterial film stimulated the barnacle settlement. The high but variable levels of antifouling activity in combination with less amount of toxicity showed the potential of these metabolites in environmentally-friendly antifouling preparations.

  17. Interactive effect of elevated pCO2 and temperature on the larval development of an inter-tidal organism, Balanus amphitrite Darwin (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Baragi, L.V.; Anil, A.C.

    mechanism that catalyses the build-up of CO2 around the RuBisCO by active transport of HCO3- into the cell under CO2 limited condition at the expense of high metabolic energy (Raven et al., 2008). The present study found, irrespective of temperature...., 2012; Wu et al., 2010); negative (Gao et al., 2012; Torstensson et al., 2012) or neutral (Gao et al., 2012; Yang and Gao, 2012). The difference in responses could be attributed to varying Carbon Concentrating Mechanism (CCM) which is an efficient...

  18. Preliminary results on the anatomy of the larval musculature of Balanus improvisus (Darwin, 1854) (Crustacea: Cirripedia: Thecostraca) using phalloidin staining in combination with confocal laserscanning microscopy

    DEFF Research Database (Denmark)

    Semmler, Henrike; Høeg, Jens Thorvald; Scholtz, Gerhard;

    2006-01-01

    The anatomy of the larval muscular systems in Balanus improvisus (Darwin, 1854) was investigated by using phalloidin staining to visualize filamentous F-actin in combination with confocal laser scanning microscopy (CLSM). The larval musculature contains an anterior muscle complex associated with ...

  19. Metamorphosis in balanomorphan, pedunculated, and parasitic barnacles

    DEFF Research Database (Denmark)

    Høeg, Jens Thorvald; Maruzzo, Diego; Okano, Keiju;

    2012-01-01

    Cypris metamorphosis was followed using video microscopy in four species of cirripeds representing the suspension-feeding pedunculated and sessile Thoracica and the parasitic Rhizocephala. Cirripede metamorphosis involves one or more highly complex molts that mark the change from a free cypris...

  20. The monophyletic origin of a remarkable sexual system in akentrogonid rhizocephalan parasites:A molecular and larval structural study

    DEFF Research Database (Denmark)

    Glenner, Henrik; Høeg, Jens Thorvald; Stenderup, Jesper;

    2010-01-01

    We use sequences from the nuclear ribosomal genes, 18S and 28S to analyze the phylogeny of the Rhizocephala Akentrogonida including two species, Clistosaccus paguri and Chthamalophilus delagei, that are critical for understanding rhizocephalan evolution but have not previously been part...

  1. Remarkable convergent evolution in specialized parasitic Thecostraca (Crustacea)

    DEFF Research Database (Denmark)

    Pérez-Losada, Marcos; Høeg, Jens Thorvald; Crandall, Keith A

    2009-01-01

    the metamorphosis found in the Facetotecta and Rhizocephala suggests a common evolutionary origin, but until now no comprehensive study has looked at the basic evolution of these thecostracan groups. Results To this end, we collected DNA sequences from three nuclear genes [18S rRNA (2,305), 28S rRNA (2...

  2. Larval development of the pedunculate barnacles Octolasmis angulata Aurivillius 1894 and Octolasmis cor Aurivillius 1892 (Cirripedia: Thoracica: Poecilasmatidae) from the gills of the mud crab, Scylla tranquebarica Fabricius, 1798.

    Science.gov (United States)

    Yap, F C; Wong, W L; Maule, A G; Brennan, G P; Lim, L H S

    2015-05-01

    Detailed studies of larval development of Octolasmis angulata and Octolasmis cor are pivotal in understanding the larval morphological evolution as well as enhancing the functional ecology. Six planktotrophic naupliar stages and one non-feeding cyprid stage are documented in details for the first time for the two species of Octolasmis. Morphologically, the larvae of O. angulata and O. cor are similar in body size, setation patterns on the naupliar appendages, labrum, dorsal setae-pores, frontal horns, cyprid carapace, fronto-lateral gland pores, and lattice organs. Numbers of peculiarities were observed on the gnathobases of the antennae and mandible throughout the naupliar life-cycle. The setation pattern on the naupliar appendages are classified based on the segmentation on the naupliar appendages. The nauplius VI of both species undergoes a conspicuous change before metamorphosis into cyprid stage. The cyprid structures begin to form and modify beneath the naupliar body towards the end of stage VI. This study emphasises the importance of the pedunculate barnacle larval developmental studies not only to comprehend the larval morphological evolution but also to fill in the gaps in understanding the modification of the naupliar structures to adapt into the cyprid life-style. PMID:25770075

  3. When similar beginnings lead to different ends: Constraints and diversity i cirripede larval development

    DEFF Research Database (Denmark)

    Høeg, Jens Thorvald; Møller, Ole Sten

    2006-01-01

    the larvae hatch as cyprids. The cypris larvae are very similar among the ingroups of the Cirripedia, but interesting variations occur in structures used for substrate location and attachment. The cyprid is specialized to both swim through the water and actively explore the substratum by walking...... on the antennules and using an array of sensory organs in search for a suitable site to attach. This unique morphology and behavior of the cyprid have enabled the Cirripedia to colonize widely different habitats ranging from hard rock to soft animal tissue. Yet, the cyprid can metamorphose into juveniles...

  4. Influence of food concentration, temperature and salinity on the larval development of Balanus amphitrite

    Digital Repository Service at National Institute of Oceanography (India)

    Anil, A.C.; Kurian, J.

    Influence of food concentration (0.5, 1 and 2 x 10 sup(5) cell ml sup(-1) of Skeletonema costatum), temperature (20 and 30 degrees C) and salinity (15, 25 and 35 ppt) on the larval development of Balanus amphitrite (Cirripedia: Thoracica...

  5. Deep phylogeny and character evolution in thecostraca (Crustacea: Maxillopoda)

    DEFF Research Database (Denmark)

    Pérez-Losada, Marcos; Høeg, Jens Thorvald; Crandall, Keith A.

    2012-01-01

    The thecostracans include the Facetotecta, Ascothoracida, and Cirripedia and show great diversity in both morphology and biology. This makes them ideal models for studying evolutionary adaptations of the larval and adult body-plan, lifestyle, and reproduction. Surprisingly, despite all the work p...... and the theories relating to the origin and diversification of this taxon....

  6. Contribution to the feeding ecology of the banded puffer fish Colomesus psittacus (Tetraodontidae) in north Brazilian mangrove creeks.

    Science.gov (United States)

    Krumme, U; Keuthen, H; Saint-Paul, U; Villwock, W

    2007-08-01

    Stomach contents were examined from 102 banded puffer, Colomesus psittacus (Tetraodontidae), caught from intertidal mangrove creeks at diurnal neap tides between June and September, 1997 (early dry season) near Bragança (north Brazil). The study found that C. psittacus were specialized predators of Cirripedia (Balanus spp.) and Brachyuran crabs (Uca spp., Pachygrapsus gracilis) (mean: 58 and 38% by dry weight, respectively), emphasizing a short food chain in the mangrove system. Cirripedia and Brachyura dominated the diet in all size classes, however, the prey spectrum narrowed with fish size. The mean daily consumption of Cirripedia and Brachyura was 6.2% body weight of C. psittacus. On average C. psittacus consumed 100.3 g x ha(-1) x d(-1) of Cirripedia and 178.7 g x ha(-1) x d(-1) of Brachyura (wet weight). The predation on Brachyuran crabs--a significant driver of fluxes of organic matter and energy in the system--provides C. psittacus with an important ecological function in the mangrove food web. A plant-animal interaction is proposed where C. psittacus exerts a mutually beneficial cleaning function on the Aufwuchs (Cirripedia and associated epibiota) of Rhizophora mangle stilt roots. Our results and those of other studies suggest that C. psittacus encounter optimum foraging conditions in the mangrove at high inundations at daylight (spring tide-day) whereas darkness and low inundations are linked to poor foraging conditions (neap tide-night). The C. psittacus resource could be used as an alternative income in the region in terms of i) sustainable catch and filet processing for exports to East Asia, ii) developing certified aquaculture methods for breeding puffers for the aquarium trade. PMID:18094820

  7. Comparação da tolerância fisiológica (temperatura e salinidade) entre as cracas (crustacea, Cirripedia) Fistulobalanus Citerosum Henry, 1974 (espécie nativa) e Amphibalanus reticulatus Utinomi, 1967 (espécie invasora)

    OpenAIRE

    Veiga, Marcos Paulo Trindade da

    2011-01-01

    Resumo: A introdução de espécies é um dos fatores que mais causa prejuízo a ecossistemas, ocasionando a perda de biodiversidade em ambientes terrestres e aquáticos, tanto marinhos quanto dulcícolas. Regiões portuárias são muito suscetíveis a este processo, e a Baía de Paranaguá é o exemplo mais próximo. Muitos organismos são frequentemente transportados entre áreas portuárias, incrustados nas embarcações ou suspensos em águas de lastro, e podem se estabelecer em locais nos quais não chegariam...

  8. Dos nuevos registros de crustáceos asociados a la piel del manatí trichechus manatus (chordata, mammalia, sirenia) de la región noroccidental de Cuba

    OpenAIRE

    Ortiz, M.; Alvarez-Alemán, A.; Angulo-Valdés, J.

    2010-01-01

    Se presentan dos especies de crustáceos asociados a la piel del manatí Trichechus manatus, en una localidad de la costa noroccidental cubana. Un cirripedio del género Chelonibia (Cirripedia, Sessillia) y un tanaidáceo del género Sinelobus (Crustacea, Peracarida) son registrados por primera vez para las aguas cubanas. También la aparición de un tanaidáceo asociado a la piel de un manatí constituye el primer registro, en Cuba. De ambas especies se presentan, además, algunos d...

  9. Further observations on zooplankton of the Potengi Estuary (Natal, Rio Grande do Norte, Brazil with special reference to the larvae of Brachyura (Crustacea, Decapoda

    Directory of Open Access Journals (Sweden)

    C Sankarankutty

    1995-01-01

    Full Text Available The present paper deals with data on zooplankton collected from the estuary of Potengi, Natal, Rio Grande do Norte, Brazil covering a period of one year from October 1992 to October 1993. Three fixed stations within the estuary located at varying distances from the mouth of the river were sampled. Sampling was done monthly when the tide was lowest. Analysis of the samples has shown clear pattern of seasonal variations in abundance of the dominant zooplankton components which are composed of Copepoda, Appendicularia, larvae of Brachyura, larvae of Cirripedia and Chaetognalha. A detailed study of the larvae of Brachyura was also attempted which showed that seven species can be identified in the samples, of which those of Aratus pisonii (H. Milne Edwards and Cardisoma guanhumi Latreille have already been described. Other five species are designated here numerically and description of various stages present in the samples are given.

  10. Predicting the Invasion Pathway of Balanus perforates in Korean Seawaters

    Directory of Open Access Journals (Sweden)

    Keun-Hyung Choi

    2013-03-01

    Full Text Available The European Common Barnacle Balanus perforatus Brugiére (Crustacea, Cirripedia has been introduced into the east coast of Korea, presumably via the ballast water of ships. The species has since been spreading along both the northern and southern coast to the east, most likely due to alongshore currents. We predicted the potential range expansion of Balanus perforatus in Korean waters using Genetic Algorithm for Rule-set Prediction (GARP, an environmental niche modeling technique. The results show that much of the southern coastal waters of Korea could be colonized by the spread of the nonindigenous species, but that the west coast is unlikely to be invaded. More sampling on the west coast would enhance the predictability of the model. To our knowledge, this is the first report of its kind for predicting marine nonindigenous species in Korean waters using GARP modeling.

  11. On the origin of a novel parasitic-feeding mode within suspension-feeding barnacles.

    Science.gov (United States)

    Rees, David John; Noever, Christoph; Høeg, Jens Thorvald; Ommundsen, Anders; Glenner, Henrik

    2014-06-16

    In his monograph on Cirripedia from 1851, Darwin pointed to a highly unusual, plateless, and most likely parasitic barnacle of uncertain phylogenetic affinity. Darwin's barnacle was Anelasma squalicola, found on deep-water sharks of the family Etmopteridae, or lantern sharks. The barnacle is uncommon and is therefore rarely studied. Recent observations by us have shown that they occur at an unusually high prevalence on the velvet belly lantern shark, Etmopterus spinax, in restricted fjord areas of western Norway. A phylogenetic analysis based on ribosomal DNA data (16S, 18S, and 28S) from 99 selected barnacle species, including all available pedunculate barnacle sequences from GenBank, shows that A. squalicola is most closely related (sister taxon) to the pedunculate barnacle Capitulum mitella. Both C. mitella and species of Pollicipes, situated one node higher in the tree, are conventional suspension feeders from the rocky intertidal. Our phylogenetic analysis now makes it possible to establish morphological homologies between A. squalicola and its sister taxon and provides the evolutionary framework to explain the unprecedented transition from a filter-feeding barnacle to a parasitic mode of life. PMID:24909326

  12. Macroepizoísmo em Libinia ferreirae (Crustacea, Brachyura, Majidae Macroepizoites on Libinia ferreirae (Crustacea, Brachyura, Majidae

    Directory of Open Access Journals (Sweden)

    Vanessa C. Winter

    2006-06-01

    Full Text Available Um estudo de distribuição dos macroepizóicos foi realizado numa população do caranguejo-aranha Libinia ferreirae Brito Capello, 1871 proveniente do litoral dos estados do Paraná e de Santa Catarina. O material biológico foi obtido junto aos pescadores, e faz parte do rejeito de pesca. Os caranguejos foram mensurados e os macroepizóicos identificados e contados. Os seguintes macroepizóicos sésseis foram registrados: Calliactis tricolor (Lesueur, 1817 (Cnidaria; Actiniaria (Cnidaria; Arca sp. (Mollusca; Ostreidae (Mollusca; Acanthodesia tenuis (Desor, 1848 (Bryozoa; Cirripedia e duas espécies tubícolas de Gammaridea (Crustacea. Além destes organismos ocorreram dois tubos desabitados e quatro animais vágeis. A anêmona C. tricolor foi a espécie mais abundante e freqüente, sendo, provavelmente, utilizada como mecanismo de camuflagem pelo caranguejo. O macroepizoísmo em L. ferreirae está relacionado com a idade ou tamanho do caranguejo, tendo maior incidência naqueles mais velhos ou de maior porte. Entretanto, a densidade dos macroepizóicos por caranguejo se mantém em torno de três. Não há relação entre o macroepizoísmo e o sexo do hospedeiro; somente fêmeas ovígeras utilizam desse recurso mais freqüentemente do que as não-ovígeras. Devido à maior área de fixação, os macroepizóicos colonizam principalmente a carapaça do caranguejo, enquanto nos pereiópodos há predominância de Bryozoa.A study of the distribution of the macroepizoites was carried out on a population of the spider crab Libinia ferreirae Brito Capello, 1871 from the Southern Brazilian coast. Crabs were obtained from shrimps and fishes by-catch. They were measured, and their macroepizoites were identified and counted. The following sessile macroepizoites were registered: Calliactis tricolor (Lesueur, 1817 (Cnidaria; Actiniaria (Cnidaria; Arca sp. (Mollusca; Ostreidae (Mollusca; Acanthodesia tenuis (Desor, 1848 (Bryozoa; Cirripedia and two species

  13. Ship hull fouling in the port of Recife, Pernambuco

    Directory of Open Access Journals (Sweden)

    Cristiane Maria Rocha Farrapeira

    2007-09-01

    Full Text Available Ports of big coastal cities are exposed to exotic species as a consequence of shipping traffic. As the Port of Recife receives an annual average of 491 ships from other regions of Brazil and from all over the world, this work was aimed at knowing which marine animals were passively transported on such vessels hulls, in order to map and monitor new bioinvasions in the area. Thus, 32 vessels of several origins were investigated between November 2005 and March 2006, samples were taken and the macrofauna identified. Sixty species of associated animals were identified, consisting of 28 sessile species, particularly the Cirripedia Balanomorpha and Lepadomorpha as dominants, 8 sedentary animals, namely Mytillidae and Dreissenidae and 23 free-living species, particularly, Caprellidae, Gammaridae, Tanaidacea, Turbellaria, Nemertea and Polychaeta. The first occurrence of Conchoderma virgatum was recorded with exact location for the Brazilian littoral, and Conchoderma auritum, Amphibalanus subalbidus and Haliplanella lineata were recorded for the first time at the littoral of Pernambuco State. The invasion pathway was confirmed for Amphibalanus reticulatus and Mytilopsis leucophaeta, invader species of the estuarine area of Recife's city. Megabalanus coccopoma was considered as a risk invader species for the region.Regiões portuárias das grandes cidades litorâneas estão sujeitas à recepção de espécies exóticas como conseqüência da movimentação dos navios. Como o Porto do Recife recebe uma média anual de 491 atracações de navios, provenientes de várias regiões do Brasil e do mundo, objetivou-se conhecer quais animais marinhos eram transportados passivamente nos cascos das embarcações para mapear e monitorar novas invasões biológicas na área. Assim, foram investigados 32 barcos de diversas origens, nos meses de novembro de 2005 a março de 2006, tendo a macrofauna sido amostrada e identificada. Foram encontradas 60 espécies de animais

  14. Diatoms and Other Epibionts Associated with Olive Ridley (Lepidochelys olivacea Sea Turtles from the Pacific Coast of Costa Rica.

    Directory of Open Access Journals (Sweden)

    Roksana Majewska

    Full Text Available Although the sea turtles have long been familiar and even iconic to marine biologists, many aspects of their ecology remain unaddressed. The present study is the first of the epizoic diatom community covering the olive ridley turtle's (Lepidochelys olivacea carapace and the first describing diatoms living on sea turtles in general, with the primary objective of providing detailed information on turtle epibiotic associations. Samples of turtle carapace including the associated diatom biofilm and epizoic macro-fauna were collected from Ostional beach (9° 59´ 23.7´´ N 85° 41´ 52.6´´ W, Costa Rica, during the arribada event in October 2013. A complex diatom community was present in every sample. In total, 11 macro-faunal and 21 diatom taxa were recorded. Amongst diatoms, the most numerous were erect (Achnanthes spp., Tripterion spp. and motile (Haslea sp., Navicula spp., Nitzschia spp., Proschkinia sp. forms, followed by adnate Amphora spp., while the most common macro-faunal species was Stomatolepas elegans (Cirripedia. Diatom densities ranged from 8179 ± 750 to 27685 ± 4885 cells mm-2. Epizoic microalgae were either partly immersed or entirely encapsulated within an exopolymeric coat. The relatively low diatom species number, stable species composition and low inter-sample dissimilarities (14.4% on average may indicate a mutualistic relationship between the epibiont and the basibiont. Dispersal of sea turtle diatoms is probably highly restricted and similar studies will help to understand both diatom diversity, evolution and biogeography, and sea turtle ecology and foraging strategies.

  15. Mesozooplankton community development at elevated CO2 concentrations: results from a mesocosm experiment in an Arctic fjord

    Directory of Open Access Journals (Sweden)

    B. Niehoff

    2013-03-01

    Full Text Available The increasing CO2 concentration in the atmosphere caused by burning fossil fuels leads to increasing pCO2 and decreasing pH in the world ocean. These changes may have severe consequences for marine biota, especially in cold-water ecosystems due to higher solubility of CO2. However, studies on the response of mesozooplankton communities to elevated CO2 are still lacking. In order to test whether abundance and taxonomic composition change with pCO2, we have sampled nine mesocosms, which were deployed in Kongsfjorden, an Arctic fjord at Svalbard, and were adjusted to eight CO2 concentrations, initially ranging from 185 μatm to 1420 μatm. Vertical net hauls were taken weekly over about one month with an Apstein net (55 μm mesh size in all mesocosms and the surrounding fjord. In addition, sediment trap samples, taken every second day in the mesocosms, were analysed to account for losses due to vertical migration and mortality. The taxonomic analysis revealed that meroplanktonic larvae (Cirripedia, Polychaeta, Bivalvia, Gastropoda, and Decapoda dominated in the mesocosms while copepods (Calanus spp., Oithona similis, Acartia longiremis and Microsetella norvegica were found in lower abundances. In the fjord copepods prevailed for most of our study. With time, abundance and taxonomic composition developed similarly in all mesocosms and the pCO2 had no significant effect on the overall community structure. Also, we did not find significant relationships between the pCO2 level and the abundance of single taxa. Changes in heterogeneous communities are, however, difficult to detect, and the exposure to elevated pCO2 was relatively short. We therefore suggest that future mesocosm experiments should be run for longer periods.

  16. Mesozooplankton community development at elevated CO2 concentrations: results from a mesocosm experiment in an Arctic fjord

    Directory of Open Access Journals (Sweden)

    J. Czerny

    2012-08-01

    Full Text Available The increasing CO2 concentration in the atmosphere caused by burning fossil fuels leads to increasing pCO2 and decreasing pH in the world oceans. These changes may have severe consequences for marine biota, especially in cold-water ecosystems due to higher solubility of CO2. However, studies on the response of mesozooplankton communities to elevated pCO2 are yet lacking. In order to test whether abundance and taxonomic composition change with pCO2, we have sampled nine mesocosms, which were deployed in Kongsfjorden, an Arctic fjord at Svalbard, and were adjusted to eight CO2 concentrations, initially ranging from 185 μatm to 1420 μatm. Samples were taken weekly over a six-week period with an Apstein net (55 μm mesh size in all mesocosms and the surrounding fjord. In addition, sediment trap samples, taken every second day in the mesocosms, were analyzed to account for losses due to vertical migration and mortality. The taxonomic analysis revealed that meroplanktonic larvae (cirripeds, polychaetes, bivalves, gastropod, and decapods dominated in the mesocosms while copepods (Calanus spp., Oithona similis, Acartia longiremis and Microsetella norvegica were found in lower abundances. In the fjord copepods prevailed for most of our study. With time, abundance and taxonomic composition developed similarly in all mesocosms; the pCO2 had no significant effect on the overall community structure. However, single taxa responded to elevated CO2 concentrations. The ratio of cirripedia nauplii to cypris larvae, the next developmental stage, in the sediment traps averaged over the entire experiment increased with pCO2 and this suggests that increased pCO2 may have delayed their development. Also, the number of bivalves, averaged over the experimental period, decreased significantly with increasing pCO2. The nature of the CO2 effect, either direct or indirect, remains open and needs to be addressed in future.

  17. Trophic structure of zooplankton in the Fram Strait in spring and autumn 2003

    Science.gov (United States)

    Blachowiak-Samolyk, Katarzyna; Kwasniewski, Slawek; Dmoch, Katarzyna; Hop, Haakon; Falk-Petersen, Stig

    2007-11-01

    The trophic structure of zooplankton was investigated in Fram Strait (north western Svalbard) in spring and autumn of 2003. Depth-stratified zooplankton samples were collected at 12 stations on the shelf (˜200 m), across the shelf-slope (˜500 m) and over deep water (>750 m), using a Multiple Plankton Sampler equipped with 0.180-mm mesh size nets. Higher zooplankton abundance and estimated biomass were found in the shelf area. Abundance and biomass were two times higher in August, when sea-surface temperature was higher than in May. Herbivores dominated numerically in May, and omnivores in August, suggesting a seasonal sequence of domination by different trophic groups. Cirripedia nauplii and Fritillaria borealis prevailed in spring, whereas copepod nauplii and Calanus finmarchicus were numerically the most important herbivores in autumn. Small copepods, Oithona similis and Triconia borealis, were the most numerous omnivorous species in both seasons, but their abundances increased in autumn. Chaetognatha (mainly Eukrohnia hamata) accounted for the highest abundance and biomass among predatory taxa at all deep-water stations and during both seasons. Regarding vertical distribution, herbivores dominated numerically in the surface layer (0-20 m), and omnivores were concentrated somewhat deeper (20-50 m) during both seasons. Maximum abundance of predators was found in the surface layer (0-20 m) in spring, and generally in the 20-50 m layer in autumn. This paper presents the first comprehensive summary of the zooplankton trophic structure in the Fram Strait area. Our goals are to improve understanding of energy transfer through this ecosystem, and of potential climate-induced changes in Arctic marine food webs.

  18. Late-summer zooplankton community structure, abundance, and distribution in the Hudson Bay system (Canada) and their relationships with environmental conditions, 2003-2006

    Science.gov (United States)

    Estrada, Rafael; Harvey, Michel; Gosselin, Michel; Starr, Michel; Galbraith, Peter S.; Straneo, Fiammetta

    2012-08-01

    Zooplankton communities were examined for the first time in three different hydrographic regions of the Hudson Bay system (HBS) in early August to early September from 2003 to 2006. Sampling was conducted at 50 stations distributed along different transects located in Hudson Bay (HB), Hudson Strait (HS), and Foxe Basin (FB). Variations in zooplankton biomass, abundance, taxonomic composition, and diversity in relation to environmental variables were studied using multivariate techniques. During all sampling years, the total zooplankton biomass was on average four times lower in HB than in HS and FB. Clustering samples by their relative species compositions revealed no interannual variation in zooplankton community but showed a marked interregional variability between the three regions. Water column stratification explained the greatest proportion (25%) of this spatial variability. According to redundancy analysis (RDA), the zooplankton taxa that contribute most to the separation of the three regions are Microcalanus spp., Oithona similis, Oncaea borealis, Aeginopsis laurentii, Sagitta elegans, Fritillaria sp., and larvae of cnidaria, chaetognatha, and pteropoda in HB; hyperiid amphipods in FB; and Pseudocalanus spp. CI-CV, Calanus glacialis CI-CVI, Calanus finmarchicus CI-CVI, Calanus hyperboreus CV-CVI, Acartia longiremis CI-CV, Metridia longa N3-N6 CI-CIII CVIf, Eukrohnia hamata, larvae of echinodermata, mollusca, cirripedia, appendicularia, and polychaeta in the northwestern and southeastern HS transects. For the HB transect, the RDA analyzed allowed us to distinguish three regions (HB west, central, and east) with different environmental gradients and zooplankton assemblages, in particular higher concentration of Pseudocalanus spp. nauplii and CI-CVI, as well as benthic macrozooplankton and meroplankton larvae in western HB. In HS, Calanoid species (mainly C. finmarchicus and C. glacialis) were mostly observed at the north shore stations associated with the

  19. Prospecção hidrobiológica da Baía de Sepetiba Color and transparence of waters of Sepetiba Bay, in Rio de Janeiro State

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    Lejeune P. H. de Oliveira

    1971-01-01

    Full Text Available Côr das águas de Sepetiba; as pròpriamente marítimas, pela Escala de Forel e as outras côres aparentes totais feitas por comparação com escalas de SÉGUY e com o Dicionário de Côres de MAERZ & PAUL, 1950. Côr Forel nº6 mostrava no litoral cirrípedes como a Tetraclita squamosa, nas rochas; Águas com a cianofícea planctônica Trichodesmium erythraeum tinham côr de "fôlha de bananeira" ou alpine green. O verde esmeralda mais intenso no local 7, com plancto maciço da diatomácea Coscinodiscus; a parte central da Baía com 150 [quilometros quadrados], cheia de larvas de camarão Penaeus schmidti, águas de cõr de ferrugem nas superfícies das águas; os estuários côr caramelo, isabellinus e bistre. Êste levantamento preliminar serve para comparações futuras, pois a Baía de Sepetiba ainda não é poluída. Futuramente haverá um pôrto de minérios com 3.000.000 de toneladas anuais, cais do pôrto, siderúrgicas e outras indústrias que a poluirão. Várias cõres de águas poluídas da Baía de Guanabara, como águas negras, águas côr de asfalto e outras escurecidas não foram encontradas em Sepetiba. Também não foram encntradas "águas vermelhas" com plancto predominante de dinoflagelados do que já vimos na Baía de Guanabara seguidos de mortandadas de peixes. A fig. 3 mostra as curvas de transparência, e a relação entre côr e transparência é dada para as côres totais aparentes. Foi marcado o coeficiente de extinção da luz K, pelo cálculo a partir do Disco de Secchi. Havendo poluições todos êsses dados que apresentamos deverão ser alterados.The apparent total color of sea by comparison with samples tested by "MAERZ & PAUL: A Dictionary of Colors, 1950". We find green colors of Forel Scale: Forel n. 5 in waters with Pheophyceae, Sargassum, and Rhodophyceae; Forel n. 6 waters in stones with the Cirripedia, the barnacle Tetraclita squamosa; the alpine green in waters with Trichodesmium exuthraeum. Emerald