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Sample records for tentaculata echinodermata deuterostomia

  1. Echinodermata: Echinoidea

    African Journals Online (AJOL)

    1991-05-15

    May 15, 1991 ... Short Communication. New southern geographical records of intertidal sea urchins (Echinodermata: Echinoidea), with notes on .... The present study shows that there is a marked decline in species richness over a small distance south of Preslies Bay. (108 kID S; Figure 1). The change from a tropical to a.

  2. Prosthogonimus cuneatus (Digenea, Prosthogonimidae in Bithynia tentaculata mollusks in Ukraine

    Directory of Open Access Journals (Sweden)

    Y. P. Zhytova

    2011-01-01

    Full Text Available Parthenitae and larvae of Prosthogonimus cuneatus Rudolphi, 1809 in the fresh water mollusk Bithynia tentaculata s were firstly found in the eastern Polissya (the Psel river bend, Sumy oblast. The paper presents the morphological characteristics of the P. cuneatus cercariae. Comparative analysis of the dimensional data of P. cuneatus sporocysts and larvae with their parthenitae and larvae described by T. A. Krasnolobova (1961, L. F. Filimonova and V. I. Shalyapina (1980, and E. Arystanov (1986 from B. tentaculata, B. inflata and B.caerulans mollusks was made.

  3. Phylogenomic analysis of the L1 retrotransposons in Deuterostomia.

    Science.gov (United States)

    Kordis, Dusan; Lovsin, Nika; Gubensek, Franc

    2006-12-01

    L1 retrotransposons constitute the largest single component of mammalian genomes. In contrast to the single remaining lineage of L1 retrotransposons in mammalian genomes, some teleost fishes contain a highly diverse L1 retrotransposon repertoire. Major evolutionary changes in L1 retrotransposon repertoires have therefore taken place in the land vertebrates (Tetrapoda). The lack of sequence data for L1 retrotransposons in the basal living Tetrapoda lineages prompted an investigation of their distribution and evolution in the genomes of the key tetrapod lineages, amphibians and reptiles, and in lungfishes. In this study, we combined genome database searches with PCR analysis to demonstrate that L1 retrotransposons are present in the genomes of lungfishes, amphibians, and lepidosaurs. Phylogenomic analysis shows that the genomes of Deuterostomia possess three highly divergent groups of L1 retrotransposons, with distinct distribution patterns. The analysis of L1 diversity shows the presence of a very large number of diverse L1 families, each with very low copy numbers, at the time of the origin of tetrapods. During the evolution of synapsids, all but one L1 lineage have been lost. This study establishes that the loss of L1 diversity and explosion in copy numbers occurred in the synapsid ancestors of mammals, and was most probably caused by severe population bottlenecks.

  4. Apodida (Echinodermata: Holothuroidea) of Thailand

    DEFF Research Database (Denmark)

    Mucharin, Arom

    Systematics of Apodida (Echinodermata: Holothuroidea), with emphasis on Thai species was studied by means of adult morphology and anatomy, ossicle morphology, and phylogenetic analysis (COI). Over 300 Apodida specimens of Apodida were found in different parts of Thailand. The order comprises 25 s...

  5. The faucet snail (Bithynia tentaculata) invades the St. Louis River Estuary

    Science.gov (United States)

    The European-origin faucet snail (Bithynia tentaculata) now numbers among the aquatic invasive species present in the St. Louis River Estuary. This snail has been in the lower Great Lakes since the early 20th century but is new to the Lake Superior basin. We found faucet snails...

  6. Equinodermos (Echinodermata) del Caribe Mexicano

    OpenAIRE

    Laguarda-Figueras, Alfredo; Solís-Marín, Francisco A.; Durán-González, Alicia; Ahearn, Cynthia Gust; Buitrón Sánchez, Blanca Estela; Torres-Vega, Juan

    2016-01-01

    Echinoderms (Echinodermata) of the Mexican Caribbean. A systematic list of the echinoderms of the Mexican Caribbean based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. This list reveals an important echinoderm biodiversity in the Mexican Caribbean, where five of the six echinoderm classes are re...

  7. Evolutionary dynamics in a novel L2 clade of non-LTR retrotransposons in Deuterostomia.

    Science.gov (United States)

    Lovsin, N; Gubensek, F; Kordi, D

    2001-12-01

    The evolution of the novel L2 clade of non-long terminal repeat (LTR) retrotransposons and their evolutionary dynamics in Deuterostomia has been examined. The short-term evolution of long interspersed nuclear element 2s (LINE2s) has been studied in 18 reptilian species by analysis of a PCR amplified 0.7-kb fragment encoding the palm/fingers subdomain of reverse transcriptase (RT). Most of the reptilian LINE2s examined are inactive since they contain multiple stop codons, indels, or frameshift mutations that disrupt the RT. Analysis of reptilian LINE2s has shown a high degree of sequence divergence and an unexpectedly large number of deletions. The evolutionary dynamics of LINE2s in reptiles has been found to be complex. LINE2s are shown to form a novel clade of non-LTR retrotransposons that is well separated from the CR1 clade. This novel L2 clade is more widely distributed than previously thought, and new representatives have been discovered in echinoderms, insects, teleost fishes, Xenopus, Squamata, and marsupials. There is an apparent absence of LINE2s from different vertebrate classes, such as cartilaginous fishes, Archosauria (birds and crocodiles), and turtles. Whereas the LINE2s are present in echinoderms and teleost fishes in a conserved form, in most tetrapods only highly degenerated pseudogenes can be found. The predominance of inactive LINE2s in Tetrapoda indicates that, in the host genomes, only inactive copies are still present. The present data indicate that the vertical inactivation of LINE2s might have begun at the time of Tetrapoda origin, 400 MYA. The evolutionary dynamics of the L2 clade in Deuterostomia can be described as a gradual vertical inactivation in Tetrapoda, stochastic loss in Archosauria and turtles, and strict vertical transmission in echinoderms and teleost fishes.

  8. Analysis of Schistosoma mansoni genes shared with Deuterostomia and with possible roles in host interactions

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    Verjovski-Almeida Sergio

    2007-11-01

    Full Text Available Abstract Background: Schistosoma mansoni is a blood helminth parasite that causes schistosomiasis, a disease that affects 200 million people in the world. Many orthologs of known mammalian genes have been discovered in this parasite and evidence is accumulating that some of these genes encode proteins linked to signaling pathways in the parasite that appear to be involved with growth or development, suggesting a complex co-evolutionary process. Results: In this work we found 427 genes conserved in the Deuterostomia group that have orthologs in S. mansoni and no members in any nematodes and insects so far sequenced. Among these genes we have identified Insulin Induced Gene (INSIG, Interferon Regulatory Factor (IRF and vasohibin orthologs, known to be involved in mammals in mevalonate metabolism, immune response and angiogenesis control, respectively. We have chosen these three genes for a more detailed characterization, which included extension of their cloned messages to obtain full-length sequences. Interestingly, SmINSIG showed a 10-fold higher expression in adult females as opposed to males, in accordance with its possible role in regulating egg production. SmIRF has a DNA binding domain, a tryptophan-rich N-terminal region and several predicted phosphorylation sites, usually important for IRF activity. Fourteen different alternatively spliced forms of the S. mansoni vasohibin (SmVASL gene were detected that encode seven different protein isoforms including one with a complete C-terminal end, and other isoforms with shorter C-terminal portions. Using S. mansoni homologs, we have employed a parsimonious rationale to compute the total gene losses/gains in nematodes, arthropods and deuterostomes under either the Coelomata or the Ecdysozoa evolutionary hypotheses; our results show a lower losses/gains number under the latter hypothesis. Conclusion: The genes discussed which are conserved between S. mansoni and deuterostomes, probably have an

  9. BIODIVERSITY OF ECHINODERMATA IN MARSEGU ISLAND

    OpenAIRE

    Bijaya Latupono; Fredy Leiwakabessy; Dominggus Rumahlatu

    2017-01-01

    Echinoderms are key species that govern the structure and balance of communities and influence the sustainability of other organisms in different types of ecosystems in sea water. This research aimed at examining the biodiversity of echinoderms, and environmental physical-chemical factors that affect the diversity of echinoderms in coastal waters of Marsegu Island. The data were collected with direct observation and all research variables were recorded. The data collection of echinodermata ty...

  10. Spatial and temporal relationships between the invasive snail Bithynia tentaculata and submersed aquatic vegetation in Pool 8 of the Upper Mississippi River

    Science.gov (United States)

    Weeks, Alicia M.; DeJager, Nathan R.; Haro, Roger J.; Sandland, Greg J.

    2017-01-01

    Bithynia tentaculata is an invasive snail that was first reported in Lake Michigan in 1871 and has since spread throughout a number of freshwater systems of the USA. This invasion has been extremely problematic in the Upper Mississippi River as the snails serve as intermediate hosts for several trematode parasites that have been associated with waterfowl mortality in the region. This study was designed to assess the abundance and distribution of B. tentaculata relative to submersed aquatic vegetation as macrophytes provide important nesting and food resources for migrating waterfowl. Temporal changes in both vegetation and snail densities were compared between 2007 and 2015. Between these years, B. tentaculata densities have nearly quadrupled despite minor changes in vegetation abundance, distribution and composition. Understanding the spatial distribution of B. tentaculata in relation to other habitat features, including submersed vegetation, and quantifying any further changes in the abundance and distribution of B. tentaculata over time will be important for better identifying areas of risk for disease transmission to waterfowl.

  11. Genetic structure of faucet snail, Bithynia tentaculata populations in North Americal based on microsattelite markers

    Science.gov (United States)

    Perez, Kathryn E.; Werren, Rebecca L.; Lynum, Christopher A.; Hartman, Levi A.; Majoros, Gabor; Cole, Rebecca A.

    2016-01-01

    Bithynia tentaculata is believed to have been extirpated from North America during the last glacial maximum. It was reintroduced into North America via the Great Lakes basin in the 1800’s and has recently been expanding its geographic range. This snail serves as intermediate host for three trematodes that cause extensive recurring morbidity and mortality events in migratory water birds along the Mississippi River. Using twelve microsatellite loci for ~200 individual snails from 11 populations in North America and Europe, we examined one of the three major geographic regions from which founding populations into the Great Lakes typically originate. Our data supports a single recolonization of North America into the Great Lakes Basin followed by subsequent introduction events from the Great Lakes to other large watersheds in North America. However, additional watersheds in Europe require sampling to confirm this result. No populations with genetic signatures indicative of North American glacial relics were found. The initial invasion of North America was likely not from the Ponto-Caspian basin, the usual source of freshwater invasive species to the Laurentian Great Lakes.

  12. Polar localization of plasma membrane Ca2+/Mg2+ ATPase correlates with the pattern of steady ionic currents in eggs of Lymnaea stagnalis and Bithynia tentaculata (Mollusca)

    NARCIS (Netherlands)

    D. Zivkovic (Dana); R. Créton (Robbert); G. Zwaan (Gideon); W.C. de Bruijn (Wim); M.R. Dohmen (M.René)

    1990-01-01

    textabstractDuring extrusion of the first polar body in eggs of Lymnaea stagnalis and Bithynia tentaculata a localized Ca2+ /Mg2+ ATPase activity was detected, using Ando's enzyme-cytochemical method for electron microscopy [Ando et al. (1981) Acta Histochem Cytochem 14:705-726]. The enzyme activity

  13. INVENTARISASI JENIS ARTHROPODA DAN ECHINODERMATA DI ZONA PASANG SURUT TIPE SUBSTRAT BERBATU PANTAI GATRA KABUPATEN MALANG

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    Arindra Trisna Widiansyah

    2016-07-01

    Pantai Gatra merupakan salah satu ekowisata pantai di Kabupaten Malang yang memiliki zona pasang surut dengan substrat dominan batu. Substrat berbatu merupakan daerah yang paling padat makroorganismenya. Arthropoda dan Echinodermata mempunyai peranan penting dari segi sumber makanan maupun ekologi. Mengingat belum adanya pelaporan jenis Arthropoda dan Echinodermata di zona pasang surut Pantai Gatra, maka dilakukan penelitian inventarisasi di daerah ini. Tujuan penelitian ini adalah invetarisasi jenis Arthropoda dan Echinodermata. Hasil penelitian tentang inventarisasi jenis Arthropoda dan Echinodermata di zona pasang surut pantai Gatra Kabupaten Malang, secara keseluruhan ditemukan 14 jenis, 13 genus, dan 11 famili dari filum Arthropoda dan Echinodermata.

  14. BIODIVERSITY OF ECHINODERMATA IN MARSEGU ISLAND

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    Bijaya Latupono

    2017-12-01

    Full Text Available Echinoderms are key species that govern the structure and balance of communities and influence the sustainability of other organisms in different types of ecosystems in sea water. This research aimed at examining the biodiversity of echinoderms, and environmental physical-chemical factors that affect the diversity of echinoderms in coastal waters of Marsegu Island. The data were collected with direct observation and all research variables were recorded. The data collection of echinodermata type was done on each plot in the middle intertidal zone and the lower intertidal zone. The results of this research found that the population of echinoderms in coastal water of Marsegu Island was composed of 4 classes, namely Ophiuroidea, Asteroidea, Echinoidea and Holothuriodea. The most common type found was Asteroidea which consisted of 3 families, 4 genera and 4 species. The results of observation showed there was a difference in echinoderm species found in the middle intertidal zone and the lower intertidal zone. The number of echinoderms species found in the middle intertidal zone was 8 species, while in the lower intertidal zone was 10 species, and there were some species that were not found in the middle intertidal zone, but they were found in the lower intertidal zone, namely Ophiopholis aculeafa, Linckia laevagata and Protoreaster nodusus. The Synapta maculata species was found in the lower intertidal zone, but it was not found in the midle intertidal zone. About 52% variation in echinoderms diversity can be explained by the regression equation model, while the remaining 48% was the influence of other factors that could not be explained by the regression equation model.

  15. Effects of 17α-ethinylestradiol on individual life-history parameters and estimated population growth rates of the freshwater gastropods Radix balthica and Bithynia tentaculata.

    Science.gov (United States)

    Hallgren, Per; Sorita, Zaoia; Berglund, Olof; Persson, Anders

    2012-04-01

    Studies of aquatic environments exposed to 17α-ethinylestradiol (EE2) have demonstrated detrimental effects on fish communities. However, much less is known about effects on macro-invertebrates and especially how long-term exposure may affect critical life stages and ultimately population dynamics. We studied the effects of EE2 on relevant endpoints for population growth in two common freshwater gastropods, Radix balthica and Bithynia tentaculata, that differ in reproductive, foraging and anti-predator strategies and endocrine systems. We quantified critical life-history parameters (mortality, somatic growth rate, days to and size at first reproduction, egg production and hatching success) in a concentration-response, life cycle experiment. The two species responded to EE2 exposure in different ways, B. tentaculata showing a significantly lower somatic growth rate and R. balthica a higher somatic growth rate. However, the magnitudes of the effects were small and EE2 exposure did not have any significant effect on estimated population growth rates for the two snail species. The significant effects of EE2 on individual endpoints, but not on population growth rate for both species, emphasise the importance of evaluating higher level effects from long-term exposure studies.

  16. Equinodermos (Echinodermata) del Pacífico Mexicano

    OpenAIRE

    Honey-Escandón, M.; Solís-Marín, F. A.; Laguarda-Figueras, A.

    2016-01-01

    Echinoderms (Echinodermata) from the Mexican Pacific. A systematic list of echinoderms of the Mexican Pacific, based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C., is presented. A total of 196 echinoderm species is recorded, distributed in 112 genera, 56 families and 20 orders. Eight new records for the Mexic...

  17. Equinodermos (Echinodermata) del Golfo de California, México

    OpenAIRE

    Solís-Marín, Francisco A.; Laguarda-Figueras, Alfredo; Durán-González, Alicia; Ahearn, Cynthia Gust; Torres Vega, Juan

    2016-01-01

    Echinoderms (Echinodermata) from the Gulf of California, Mexico. A systematic list of the echinoderms of the Gulf of California, based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. A total of 193 echinoderm species is recorded, distributed in 108 genera, 51 families and 19 orders. 12 new records...

  18. Three new records of asteroids (Echinodermata: Asteroidea from Peru Tres nuevos registros de asteroideos (Echinodermata: Asteroidea de Perú

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    Yuri Hooker

    2012-02-01

    Full Text Available The aim of this work is to present three new shallow water (4 - >50 m records of asteroids (Echinodermata: Asteroidea for the Peruvian fauna: Astropecten regalis Gray, 1840, Paulia horrida Gray 1840 and Meyenaster gelatinosus (Meyen, 1834. Astropecten regalis geographical distribution is known that ranges from Gulf of California to Panama, this discovery extends its distribution to Mancora, Peru. Paulia horrida is known from Baja California to Isla Cocos, Costa Rica, and this record extends its southern distribution limit to Punta Sal, Peru. Meyenaster gelatinosus was considered endemic to Chilean waters, however, this record confirm its presence in Peru extending its northern distribution limit to San Juan de Marcona, Peru. Morphological and habitat information on this four species is provided, together with live pictures.En el presente trabajo se registran 3 nuevos asteroideos (Echinodermata: Asteroidea de aguas someras (4 - >50 m para el Perú: Astropecten regalis Gray, 1840, Paulia horrida Gray 1840 y Meyenaster gelatinosus (Meyen, 1834. Astropecten regalis se conocía desde el Golfo de California hasta Panamá, en el presente trabajo, se amplía su distribución hasta Máncora, Perú. La distribución geográfica de Paulia horrida era conocida desde Baja California, hasta Isla Cocos, Costa Rica, en este estudio se amplía su distribución geográfica hasta Punta Sal, Perú. A Meyenaster gelatinosus se le conocía solo de Chile, en el presente trabajo se registra y confirma su presencia en el Perú, ampliando su distribución norte hasta San Juan de Marcona. Se proporciona información morfológica de las especies, características del hábitat y fotografías in situ y de los especímenes recién recolectados.

  19. Geinitzaster gen.n. (Asteroidea, Echinodermata) from the Upper Cenomanian strata of the Bohemian Cretaceous Basin

    Czech Academy of Sciences Publication Activity Database

    Žítt, Jiří

    2005-01-01

    Roč. 56, č. 4 (2005), s. 317-326 ISSN 1335-0552 R&D Projects: GA ČR GA206/01/1580 Institutional research plan: CEZ:AV0Z3013912 Keywords : Cenomanian * Asteroidea * Echinodermata Subject RIV: EG - Zoology Impact factor: 0.449, year: 2005 http://www.geologicacarpathica.sk/src/main.php

  20. Global diversity and phylogeny of the Asteroidea (Echinodermata.

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    Christopher L Mah

    Full Text Available Members of the Asteroidea (phylum Echinodermata, popularly known as starfish or sea stars, are ecologically important and diverse members of marine ecosystems in all of the world's oceans. We present a comprehensive overview of diversity and phylogeny as they have figured into the evolution of the Asteroidea from Paleozoic to the living fauna. Living post-Paleozoic asteroids, the Neoasteroidea, are morphologically separate from those in the Paleozoic. Early Paleozoic asteroid faunas were diverse and displayed morphology that foreshadowed later living taxa. Preservation presents significant difficulties, but fossil occurrence and current accounts suggests a diverse Paleozoic fauna, which underwent extinction around the Permian-Triassic interval was followed by re-diversification of at least one surviving lineage. Ongoing phylogenetic classification debates include the status of the Paxillosida and the Concentricycloidea. Fossil and molecular evidence has been and continues to be part of the ongoing evolution of asteroid phylogenetic research. The modern lineages of asteroids include the Valvatacea, the Forcipulatacea, the Spinlosida, and the Velatida. We present an overview of diversity in these taxa, as well as brief notes on broader significance, ecology, and functional morphology of each. Although much asteroid taxonomy is stable, many new taxa remain to be discovered with many new species currently awaiting description. The Goniasteridae is currently one of the most diverse families within the Asteroidea. New data from molecular phylogenetics and the advent of global biodiversity databases, such as the World Asteroidea Database (http://www.marinespecies.org/Asteroidea/ present important new springboards for understanding the global biodiversity and evolution of asteroids.

  1. Finding the Exotic Faucet Snail (Bithynia tentaculata): Investigation of Waterbird Die-Offs on the Upper Mississippi River National Wildlife and Fish Refuge

    Science.gov (United States)

    Sauer, Jennifer S.; Cole, Rebecca A.; Nissen, James M.

    2007-01-01

    Beginning in 2002, there have been major waterbird die-offs every spring and fall in Lake Onalaska (Navigation Pool 7 of the Upper Mississippi River) located near La Crosse, Wisconsin. This area is part of the Upper Mississippi River National Wildlife and Fish Refuge (UMR Refuge) and lies within the Mississippi Flyway, through which an estimated 40 percent of the continent's waterfowl migrate. Through the 2006 spring migration, total mortality on the UMR Refuge was estimated at 22,000 to 26,000 birds, primarily American coots (Fulica americana) and lesser scaup (Aythya affinis). Two trematodes (Sphaeridiotrema globulus and Cyathocotyle bushiensis) that use the exotic faucet snail (Bithynia tentaculata) as an intermediate host were found to infect and kill the waterbirds. The faucet snail was introduced into the United States from Europe in the late 1800s. Because Lake Onalaska is a major spring and fall stop-over area for waterfowl in the Mississippi Flyway, concerns were raised that the snail and trematodes may be spreading to other waterfowl stop-over areas on the river. Exploratory sampling for faucet snails was conducted in 2005 and 2006 in navigation Pools 4-9 (excluding Pool 5a which is located between Pools 5 and 6), 11, and 13. Infected snails were found in all the sampled pools except Pool 6. To our knowledge, these are the first records of faucet snails and associated trematodes beyond those found in Pool 7, Lake Onalaska. Waterbird die-offs are becoming a UMR Refuge-wide problem. Information obtained through research and monitoring, including the identification of the origin of infections in snails and birds and the role various environmental factors have on this process, should help guide managers to develop effective mitigation and control measures.

  2. Bioactive substances with anti-neoplastic efficacy from marine invertebrates: Bryozoa, Mollusca, Echinodermata and Urochordata.

    Science.gov (United States)

    Sima, Peter; Vetvicka, Vaclav

    2011-11-10

    The marine environment provides a rich source of natural products with potential therapeutic application. This has resulted in an increased rate of pharmaceutical agents being discovered in marine animals, particularly invertebrates. Our objective is to summarize the most promising compounds which have the best potential and may lead to use in clinical practice, show their biological activities and highlight the compounds currently being tested in clinical trials. In this paper, we focused on Bryozoa, Mollusca, Echinodermata and Urochordata.

  3. Bioactive substances with anti-neoplastic efficacy from marine invertebrates: Bryozoa, Mollusca, Echinodermata and Urochordata

    Science.gov (United States)

    Sima, Peter; Vetvicka, Vaclav

    2011-01-01

    The marine environment provides a rich source of natural products with potential therapeutic application. This has resulted in an increased rate of pharmaceutical agents being discovered in marine animals, particularly invertebrates. Our objective is to summarize the most promising compounds which have the best potential and may lead to use in clinical practice, show their biological activities and highlight the compounds currently being tested in clinical trials. In this paper, we focused on Bryozoa, Mollusca, Echinodermata and Urochordata. PMID:22087434

  4. Habitat Distribution and Comparison of Brittle Star (Echinodermata: Ophiuroidea) Arm Regeneration on Moorea, French Polynesia

    OpenAIRE

    Chinn, Sarah

    2006-01-01

    Autotomy and regeneration are widespread in many groups of invertebrates and vertebrates, such as annelids, crustaceans, amphibians, and reptiles. Regeneration is common in all classes of Echinodermata and prevalent in ophiuroid brittle stars. Moorea, French Polynesia was surveyed for species of brittle stars living on coastal areas of the island in different habitats. Ophiuroid populations were sampled in habitats such as a mangrove marsh, a sandy beach with coral rubble and a jetty...

  5. Equinodermos (Echinodermata) de las aguas mexicanas del Golfo de México

    OpenAIRE

    Durán-González, Alicia; Laguarda-Figueras, Alfredo; Solís-Marín, Francisco A.; Buitrón Sánchez, Blanca Estela; Ahearn, Cynthia Gust; Torres-Vega, Juan

    2016-01-01

    Echinoderms (Echinodermata) from the Mexican waters of the Gulf of Mexico. We present a systematic list of the echinoderms from Gulf of Mexico’s Mexican waters based on specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. This list reveals an important echinoderm biodiversity present in the Gulf of Mexico, where five of the s...

  6. First record of the swimming sea cucumber Enypniastes eximia Théel, 1882 (Echinodermata: Holothuroidea in Peruvian waters

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    Francisco Alonso Solís-Marín

    2012-10-01

    Full Text Available Enypniastes eximia Théel, 1882 (Echinodermata: Holothuroidea a swimming sea cucumber is reported for the first time from Peru. The species was collected in the Continental rise (563-1,201 m off Trujillo Department. Reference material has been deposited in the Coleccion Cientifica del Instituto del Mar del Peru (IMARPE, Lima, Peru.

  7. The central nervous system of sea cucumbers (Echinodermata: Holothuroidea shows positive immunostaining for a chordate glial secretion

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    Grondona Jesus M

    2009-06-01

    Full Text Available Abstract Background Echinoderms and chordates belong to the same monophyletic taxon, the Deuterostomia. In spite of significant differences in body plan organization, the two phyla may share more common traits than was thought previously. Of particular interest are the common features in the organization of the central nervous system. The present study employs two polyclonal antisera raised against bovine Reissner's substance (RS, a secretory product produced by glial cells of the subcomissural organ, to study RS-like immunoreactivity in the central nervous system of sea cucumbers. Results In the ectoneural division of the nervous system, both antisera recognize the content of secretory vacuoles in the apical cytoplasm of the radial glia-like cells of the neuroepithelium and in the flattened glial cells of the non-neural epineural roof epithelium. The secreted immunopositive material seems to form a thin layer covering the cell apices. There is no accumulation of the immunoreactive material on the apical surface of the hyponeural neuroepithelium or the hyponeural roof epithelium. Besides labelling the supporting cells and flattened glial cells of the epineural roof epithelium, both anti-RS antisera reveal a previously unknown putative glial cell type within the neural parenchyma of the holothurian nervous system. Conclusion Our results show that: a the glial cells of the holothurian tubular nervous system produce a material similar to Reissner's substance known to be synthesized by secretory glial cells in all chordates studied so far; b the nervous system of sea cucumbers shows a previously unrealized complexity of glial organization. Our findings also provide significant clues for interpretation of the evolution of the nervous system in the Deuterostomia. It is suggested that echinoderms and chordates might have inherited the RS-producing radial glial cell type from the central nervous system of their common ancestor, i.e., the last common

  8. Phylogenomic Analyses of Echinodermata Support the Sister Groups of Asterozoa and Echinozoa

    Science.gov (United States)

    Reich, Adrian; Dunn, Casey; Akasaka, Koji; Wessel, Gary

    2015-01-01

    Echinoderms (sea urchins, sea stars, brittle stars, sea lilies and sea cucumbers) are a group of diverse organisms, second in number within deuterostome species to only the chordates. Echinoderms serve as excellent model systems for developmental biology due to their diverse developmental mechanisms, tractable laboratory use, and close phylogenetic distance to chordates. In addition, echinoderms are very well represented in the fossil record, including some larval features, making echinoderms a valuable system for studying evolutionary development. The internal relationships of Echinodermata have not been consistently supported across phylogenetic analyses, however, and this has hindered the study of other aspects of their biology. In order to test echinoderm phylogenetic relationships, we sequenced 23 de novo transcriptomes from all five clades of echinoderms. Using multiple phylogenetic methods at a variety of sampling depths we have constructed a well-supported phylogenetic tree of Echinodermata, including support for the sister groups of Asterozoa (sea stars and brittle stars) and Echinozoa (sea urchins and sea cucumbers). These results will help inform developmental and evolutionary studies specifically in echinoderms and deuterostomes in general. PMID:25794146

  9. Phylogenomic analyses of Echinodermata support the sister groups of Asterozoa and Echinozoa.

    Directory of Open Access Journals (Sweden)

    Adrian Reich

    Full Text Available Echinoderms (sea urchins, sea stars, brittle stars, sea lilies and sea cucumbers are a group of diverse organisms, second in number within deuterostome species to only the chordates. Echinoderms serve as excellent model systems for developmental biology due to their diverse developmental mechanisms, tractable laboratory use, and close phylogenetic distance to chordates. In addition, echinoderms are very well represented in the fossil record, including some larval features, making echinoderms a valuable system for studying evolutionary development. The internal relationships of Echinodermata have not been consistently supported across phylogenetic analyses, however, and this has hindered the study of other aspects of their biology. In order to test echinoderm phylogenetic relationships, we sequenced 23 de novo transcriptomes from all five clades of echinoderms. Using multiple phylogenetic methods at a variety of sampling depths we have constructed a well-supported phylogenetic tree of Echinodermata, including support for the sister groups of Asterozoa (sea stars and brittle stars and Echinozoa (sea urchins and sea cucumbers. These results will help inform developmental and evolutionary studies specifically in echinoderms and deuterostomes in general.

  10. Phylogenomic analyses of Echinodermata support the sister groups of Asterozoa and Echinozoa.

    Science.gov (United States)

    Reich, Adrian; Dunn, Casey; Akasaka, Koji; Wessel, Gary

    2015-01-01

    Echinoderms (sea urchins, sea stars, brittle stars, sea lilies and sea cucumbers) are a group of diverse organisms, second in number within deuterostome species to only the chordates. Echinoderms serve as excellent model systems for developmental biology due to their diverse developmental mechanisms, tractable laboratory use, and close phylogenetic distance to chordates. In addition, echinoderms are very well represented in the fossil record, including some larval features, making echinoderms a valuable system for studying evolutionary development. The internal relationships of Echinodermata have not been consistently supported across phylogenetic analyses, however, and this has hindered the study of other aspects of their biology. In order to test echinoderm phylogenetic relationships, we sequenced 23 de novo transcriptomes from all five clades of echinoderms. Using multiple phylogenetic methods at a variety of sampling depths we have constructed a well-supported phylogenetic tree of Echinodermata, including support for the sister groups of Asterozoa (sea stars and brittle stars) and Echinozoa (sea urchins and sea cucumbers). These results will help inform developmental and evolutionary studies specifically in echinoderms and deuterostomes in general.

  11. Primer registro de Heterocucumis godeffroyi(Semper, 1868 (Echinodermata: Holothuroidea en el mar peruano

    Directory of Open Access Journals (Sweden)

    Francisco Alonso Solís-Marín

    2013-06-01

    Full Text Available Se registra por primera vez para el Perú la especie de pepino de mar Heterocucumis godeffroyi(Semper, 1868 (Echinodermata: Holothuroidea. La especie fue recolectada a 19 m de profundidad en Pucusana, de-partamento de Lima. Este registro representa el límite más norteño de distribución de la especie reconocido hasta el momento. Material de referencia se encuentra depositado en la Colección de Zoología Acuática, del Laboratorio de Biología Marina, Departamento de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia, Lima, Perú.

  12. Primer registro de Florometra magellanica (Bell, 1882 (Echinodermata: Crinoidea para el Perú

    Directory of Open Access Journals (Sweden)

    Elba Prieto Rios

    2011-08-01

    Full Text Available Se registra por primera vez para el Perú al Crinoideo (Echinodermata Florometra magellanica (Bell, 1882. La especie fue recolectada en el talud continental (360 – 814 m frente al departamento de Piura al norte del Perú (3°38,67’S, 81° 2,73’W. El material de referencia se encuentra depositado en la Colección Científica del Instituto del mar del Perú (IMARPE, Lima, Perú y en la Colección Nacional de Equinodermos de la Universidad Nacional Autónoma de México, Ciudad de México.

  13. A taxonomic review of the genus Astrocharis Koehler (Echinodermata: Ophiuroidea: Asteroschematidae), with a description of a new species.

    Science.gov (United States)

    Okanishi, Masanori; Fujita, Toshihiko

    2011-02-01

    A revision of the genus Astrocharis Koehler (Echinodermata: Ophiuroidea: Asteroschematidae) is based on 41 specimens, including three syntypes of Astrocharis virgo Koehler, one syntype of Astrocharis ijimai Matsumoto and the holotype of Astrocharis gracilis Mortensen. Astrocharis gracilis is a junior subjective synonym of A. ijimai. A. virgo and A. ijimai are redescribed. A new species, Astrocharis monospinosa is described from southwestern Japan. A tabular key to the three species of the genus Astrocharis is provided.

  14. Higher ribosomal RNA substitution rates in Bacillariophyceae and Dasycladales than in Mollusca, Echinodermata, and Actinistia-Tetrapoda.

    Science.gov (United States)

    Sorhannus, U

    1996-09-01

    Molecular evolutionary rates within two protistan and three metazoan taxa were estimated using divergence times derived from fossil records. The results indicate that the small-subunit rRNA sequences within Dasycladales (Chlorophyta) and Bacillariophyceae evolved at a rate approximately two to three times faster than that estimated within Echinodermata, Mollusca, and Actinistia-Tetrapoda. It was concluded that this twofold discrepancy demonstrates actual taxonomic differences in the fixation rate of mutations in the small-subunit rRNA.

  15. A NEW, EARLY CROWN-GROUP ASTEROID (ECHINODERMATA FROM THE NORIAN (TRIASSIC OF NORTHERN ITALY

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    DANIEL B. BLAKE

    2000-07-01

    Full Text Available Noriaster barberoi gen. et. sp. n. is based on a single specimen from the Calcare di Zorzino (Norian, Triassic of northern Italy. A member of the surviving Poraniidae (Valvatida; Echinodermata, N. barberoi is the oldest-known species assignable to a Jurassic and younger family and the first such species known from the Triassic. No Paleozoic species with close affinities with crown-group families has been recognized. Noriaster and the slightly older Triassic genus Trichasteropsis from the Muschelkalk of Germany together indicate that the diversification of crown-group asteroids was well underway at least by Middle and Late Triassic time. Phylogeny of crown-group asteroids is problematic because extant familial-level taxa are morphologically divergent, and they exhibit comparatively few uncontested characters that clearly indicate phylogenetic affinities and sequence. Familial assignment of Noriaster is supported by a new cladistic analysis. To the student of living asteroids, the appearance of a living Noriaster would be remarkable only because it would seem so commonplace. To the extent that form correlates with function, Noriaster suggests that modern asteroid life modes emerged quite promptly during the Mesozoic asteroid diversification. 

  16. Starfish (Asteroidea, Echinodermata) from the Faroe Islands; spatial distribution and abundance

    Science.gov (United States)

    Ringvold, H.; Andersen, T.

    2016-01-01

    "Marine benthic fauna of the Faroe Islands" (BIOFAR) is a large programme with a focus on collecting invertebrate fauna from the Faroes (62°N and 7°W). Cruises were undertaken from 1987 to 1990, and starfish (Asteroidea, Echinodermata) collected during this time were analysed. Asteroidea were sampled at ~50% of all BIOFAR stations. A Detritus sledge and a Triangular dredge proved to be the most efficient equipment, collecting over 60% of the specimens. In total 2473 specimens were collected from 20 to 1500 m depth, including 41 species from 17 families and 31 genera. Henricia pertusa (O. F. Müller, 1776) group, Pontaster tenuispinus (Düben & Koren, 1846), and Leptychaster arcticus (M. Sars, 1851) showed highest relative abundance. Maximum species diversity was found at 500-700 m depth, which coincides with the transition zone of water masses (North Icelandic Winter Water and Arctic Intermediate Water (NI/AI)) at approximately 400-600 m depth. 63% of the species were recorded at an average-weighted depth above 600 m. Two different ordination methods (detrended correspondence analysis (DCA) and nonmetric multidimensional scaling (NMDS)) gave highly consistent representations of the community structure gradients. The first ordination axis scores did not show significant relationships with any environmental variable. Biological covariates like the presence of Lophelia corals were not significantly related to ordination scores on any axis. The second ordination axis scores were significantly correlated with depth. Temperature and salinity were highly correlated (r=0.90), and both negatively correlated with depth (r=-0.69 and r=-0.57, respectively).

  17. Origin and evolutionary plasticity of the gastric caecum in sea urchins (Echinodermata: Echinoidea)

    Science.gov (United States)

    2010-01-01

    Background The digestive tract of many metazoan invertebrates is characterized by the presence of caeca or diverticula that serve secretory and/or absorptive functions. With the development of various feeding habits, distinctive digestive organs may be present in certain taxa. This also holds true for sea urchins (Echinodermata: Echinoidea), in which a highly specialized gastric caecum can be found in members of a derived subgroup, the Irregularia (cake urchins, sea biscuits, sand dollars, heart urchins, and related forms). As such a specialized caecum has not been reported from "regular" sea urchin taxa, the aim of this study was to elucidate its evolutionary origin. Results Using morphological data derived from dissection, magnetic resonance imaging, and extensive literature studies, we compare the digestive tract of 168 echinoid species belonging to 51 extant families. Based on a number of characters such as topography, general morphology, mesenterial suspension, and integration into the haemal system, we homologize the gastric caecum with the more or less pronounced dilation of the anterior stomach that is observed in most "regular" sea urchin taxa. In the Irregularia, a gastric caecum can be found in all taxa except in the Laganina and Scutellina. It is also undeveloped in certain spatangoid species. Conclusions According to our findings, the sea urchin gastric caecum most likely constitutes a synapomorphy of the Euechinoidea. Its occurrence in "regular" euechinoids is linked to the presence of an additional festoon of the anterior stomach in ambulacrum III. Both structures, the additional festoon and the gastric caecum, are absent in the sister taxon to the Euechinoidea, the Cidaroida. Since the degree of specialization of the gastric caecum is most pronounced in the predominantly sediment-burrowing irregular taxa, we hypothesize that its evolution is closely linked to the development of more elaborate infaunal lifestyles. We provide a comprehensive study of

  18. Origin and evolutionary plasticity of the gastric caecum in sea urchins (Echinodermata: Echinoidea

    Directory of Open Access Journals (Sweden)

    Rolet Gauthier

    2010-10-01

    Full Text Available Abstract Background The digestive tract of many metazoan invertebrates is characterized by the presence of caeca or diverticula that serve secretory and/or absorptive functions. With the development of various feeding habits, distinctive digestive organs may be present in certain taxa. This also holds true for sea urchins (Echinodermata: Echinoidea, in which a highly specialized gastric caecum can be found in members of a derived subgroup, the Irregularia (cake urchins, sea biscuits, sand dollars, heart urchins, and related forms. As such a specialized caecum has not been reported from "regular" sea urchin taxa, the aim of this study was to elucidate its evolutionary origin. Results Using morphological data derived from dissection, magnetic resonance imaging, and extensive literature studies, we compare the digestive tract of 168 echinoid species belonging to 51 extant families. Based on a number of characters such as topography, general morphology, mesenterial suspension, and integration into the haemal system, we homologize the gastric caecum with the more or less pronounced dilation of the anterior stomach that is observed in most "regular" sea urchin taxa. In the Irregularia, a gastric caecum can be found in all taxa except in the Laganina and Scutellina. It is also undeveloped in certain spatangoid species. Conclusions According to our findings, the sea urchin gastric caecum most likely constitutes a synapomorphy of the Euechinoidea. Its occurrence in "regular" euechinoids is linked to the presence of an additional festoon of the anterior stomach in ambulacrum III. Both structures, the additional festoon and the gastric caecum, are absent in the sister taxon to the Euechinoidea, the Cidaroida. Since the degree of specialization of the gastric caecum is most pronounced in the predominantly sediment-burrowing irregular taxa, we hypothesize that its evolution is closely linked to the development of more elaborate infaunal lifestyles. We

  19. Evolution of a novel muscle design in sea urchins (Echinodermata: Echinoidea.

    Directory of Open Access Journals (Sweden)

    Alexander Ziegler

    Full Text Available The sea urchin (Echinodermata: Echinoidea masticatory apparatus, or Aristotle's lantern, is a complex structure composed of numerous hard and soft components. The lantern is powered by various paired and unpaired muscle groups. We describe how one set of these muscles, the lantern protractor muscles, has evolved a specialized morphology. This morphology is characterized by the formation of adaxially-facing lobes perpendicular to the main orientation of the muscle, giving the protractor a frilled aspect in horizontal section. Histological and ultrastructural analyses show that the microstructure of frilled muscles is largely identical to that of conventional, flat muscles. Measurements of muscle dimensions in equally-sized specimens demonstrate that the frilled muscle design, in comparison to that of the flat muscle type, considerably increases muscle volume as well as the muscle's surface directed towards the interradial cavity, a compartment of the peripharyngeal coelom. Scanning electron microscopical observations reveal that the insertions of frilled and flat protractor muscles result in characteristic muscle scars on the stereom, reflecting the shapes of individual muscles. Our comparative study of 49 derived "regular" echinoid species using magnetic resonance imaging (MRI shows that frilled protractor muscles are found only in taxa belonging to the families Toxopneustidae, Echinometridae, and Strongylocentrotidae. The onset of lobe formation during ontogenesis varies between species of these three families. Because frilled protractor muscles are best observed in situ, the application of a non-invasive imaging technique was crucial for the unequivocal identification of this morphological character on a large scale. Although it is currently possible only to speculate on the functional advantages which the frilled muscle morphology might confer, our study forms the anatomical and evolutionary framework for future analyses of this unusual

  20. Evolution of a Novel Muscle Design in Sea Urchins (Echinodermata: Echinoidea)

    Science.gov (United States)

    Ziegler, Alexander; Schröder, Leif; Ogurreck, Malte; Faber, Cornelius; Stach, Thomas

    2012-01-01

    The sea urchin (Echinodermata: Echinoidea) masticatory apparatus, or Aristotle's lantern, is a complex structure composed of numerous hard and soft components. The lantern is powered by various paired and unpaired muscle groups. We describe how one set of these muscles, the lantern protractor muscles, has evolved a specialized morphology. This morphology is characterized by the formation of adaxially-facing lobes perpendicular to the main orientation of the muscle, giving the protractor a frilled aspect in horizontal section. Histological and ultrastructural analyses show that the microstructure of frilled muscles is largely identical to that of conventional, flat muscles. Measurements of muscle dimensions in equally-sized specimens demonstrate that the frilled muscle design, in comparison to that of the flat muscle type, considerably increases muscle volume as well as the muscle's surface directed towards the interradial cavity, a compartment of the peripharyngeal coelom. Scanning electron microscopical observations reveal that the insertions of frilled and flat protractor muscles result in characteristic muscle scars on the stereom, reflecting the shapes of individual muscles. Our comparative study of 49 derived “regular” echinoid species using magnetic resonance imaging (MRI) shows that frilled protractor muscles are found only in taxa belonging to the families Toxopneustidae, Echinometridae, and Strongylocentrotidae. The onset of lobe formation during ontogenesis varies between species of these three families. Because frilled protractor muscles are best observed in situ, the application of a non-invasive imaging technique was crucial for the unequivocal identification of this morphological character on a large scale. Although it is currently possible only to speculate on the functional advantages which the frilled muscle morphology might confer, our study forms the anatomical and evolutionary framework for future analyses of this unusual muscle design among

  1. Abyssal fauna of the UK-1 polymetallic nodule exploration claim, Clarion-Clipperton Zone, central Pacific Ocean: Echinodermata

    Science.gov (United States)

    Glover, Adrian G; Wiklund, Helena; Rabone, Muriel; Amon, Diva J; Smith, Craig R; O'Hara, Tim; Mah, Christopher L

    2016-01-01

    Abstract We present data from a DNA taxonomy register of the abyssal benthic Echinodermata collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise ‘AB01’ to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration claim ‘UK-1’ in the eastern Clarion-Clipperton Zone (CCZ), central Pacific Ocean abyssal plain. Morphological and genetic data are presented for 17 species (4 Asteroidea, 4 Crinoidea, 2 Holothuroidea and 7 Ophiuroidea) identified by a combination of morphological and genetic data. No taxa matched previously published genetic sequences, but 8 taxa could be assigned to previously-described species based on morphology, although here we have used a precautionary approach in taxon assignments to avoid over-estimating species ranges. The Clarion-Clipperton Zone is a region undergoing intense exploration for potential deep-sea mineral extraction. We present these data to facilitate future taxonomic and environmental impact study by making both data and voucher materials available through curated and accessible biological collections. PMID:26929713

  2. Design of phylum-specific hybrid primers for DNA barcoding: addressing the need for efficient COI amplification in the Echinodermata.

    Science.gov (United States)

    Hoareau, T B; Boissin, E

    2010-11-01

    Recent research has shown the usefulness of the Folmer region of the cytochrome oxidase I (COI) as a genetic barcode to assist in species delimitation of echinoderms. However, amplification of COI is often challenging in echinoderms (low success or pseudogenes). We present a method that allows the design of phylum-specific hybrid primers, and use this to develop COI primers for the Echinodermata. We aligned COI sequences from 310 echinoderm species and designed all possible primers along the consensus sequence with two methods (standard degenerate and hybrid). We found much lower degeneracy for hybrid primers (4-fold degeneracy) than for standard degenerate primers (≥48-fold degeneracy). We then designed the most conserved hybrid primers to amplify a >500-bp region within COI. These primers successfully amplified this gene region in all tested taxa (123 species across all echinoderm classes). Sequencing of 30 species among these confirmed both the quality of the sequences (>500 bp, no pseudogenes) and their utility as a DNA barcode. This method should be useful for developing primers for other mitochondrial genes and other phyla. The method will also be of interest for the development of future projects involving both community-based genetic assessments on macroorganisms and biodiversity assessment of environmental samples using high-throughput sequencing. © 2010 Blackwell Publishing Ltd.

  3. A new species of brooding Psolidae (Echinodermata: Holothuroidea) from deep-sea off Argentina, Southwestern Atlantic Ocean

    Science.gov (United States)

    Martinez, Mariano I.; Penchaszadeh, Pablo E.

    2017-12-01

    This paper describes a new species of Psolus (Holothuroidea, Echinodermata), P. lawrencei sp. nov., (19 specimens) found in the deep sea (308-1398 m) in the Southwestern Atlantic Ocean (SWAO) (around 38°S-54°W) with brooders (up to 3.15 mm) in the tentacles of females and a penis-like genital papilla on males. The presence of dorsal scales, the concave shape of the ossicles with a bridge, the distribution of podia on the dorsal side and the absence of large and conspicuous oral and anal valves are unique for this species. Furthermore, this is the first species of this genus found outside Antarctica that broods between its tentacles. The paper also reviews the reproductive, brooding development and morphological characteristics of P. lawrencei sp. nov. and compares them with those of several members of the family Psolidae. Finally, a possible connectivity between the deep-sea populations in the SWAO and in Antarctica is considered based on the appearance of a similar reproductive pattern in populations found in both areas, which suggests a past or present connection between these regions.

  4. Biology of Incidental Catch Sea Star Stellaster childreni Gray, 1840 (Echinodermata: Asteroidea, from Malaysian Borneo Exclusive Economic Zone

    Directory of Open Access Journals (Sweden)

    Ruhana Hassan

    2017-01-01

    Full Text Available Sea star (class Asteroidea, phylum Echinodermata is one of the most successful marine organisms inhabiting a wide range of habitats. As one of the key stone species, sea stars are responsible for maintaining much of the local diversity of species within certain communities. Malaysian Exclusive Economic Zone (EEZ Resource Survey had been carried out from 16th Aug to 6th Nov 2015 and one of the invertebrate by-catch organisms is sea star Stellaster childreni Gray, 1840. This study documents morphological characters and diet of the sea star, besides providing brief descriptions of the habitats based on particle size analysis and vessel log data sheet. A total of 217 individuals had been examined throughout this study. Fragments of flora and fauna were found in the gut including Mollusca (gastropod, bivalves, and scaphopods, sponge seagrass, and seaweed as well as benthic Foraminifera. Stellaster childreni were found at depth of 45 m to 185 m in the South China Sea off Sarawak Malaysia, with various sea bottom substrata. Approximately 41% of S. childreni were found at a mixture of sandy and muddy substratum, followed by mixture of sandy and coral (19.3%, muddy substratum (17.5%, coral substratum (11.5%, and sandy areas (10.6%. The widely distributed sea star on different types of sea beds suggested healthy deep sea ecosystem; thus Malaysia should explore further potential fisheries resources in the EEZ off Sarawak coast.

  5. Comparative morphology of the axial complex and interdependence of internal organ systems in sea urchins (Echinodermata: Echinoidea

    Directory of Open Access Journals (Sweden)

    Ziegler Alexander

    2009-06-01

    Full Text Available Abstract Background The axial complex of echinoderms (Echinodermata is composed of various primary and secondary body cavities that interact with each other. In sea urchins (Echinoidea, structural differences of the axial complex in "regular" and irregular species have been observed, but the reasons underlying these differences are not fully understood. In addition, a better knowledge of axial complex diversity could not only be useful for phylogenetic inferences, but improve also an understanding of the function of this enigmatic structure. Results We therefore analyzed numerous species of almost all sea urchin orders by magnetic resonance imaging, dissection, histology, and transmission electron microscopy and compared the results with findings from published studies spanning almost two centuries. These combined analyses demonstrate that the axial complex is present in all sea urchin orders and has remained structurally conserved for a long time, at least in the "regular" species. Within the Irregularia, a considerable morphological variation of the axial complex can be observed with gradual changes in topography, size, and internal architecture. These modifications are related to the growing size of the gastric caecum as well as to the rearrangement of the morphology of the digestive tract as a whole. Conclusion The structurally most divergent axial complex can be observed in the highly derived Atelostomata in which the reorganization of the digestive tract is most pronounced. Our findings demonstrate a structural interdependence of various internal organs, including digestive tract, mesenteries, and the axial complex.

  6. Comparative morphology of the axial complex and interdependence of internal organ systems in sea urchins (Echinodermata: Echinoidea)

    Science.gov (United States)

    Ziegler, Alexander; Faber, Cornelius; Bartolomaeus, Thomas

    2009-01-01

    Background The axial complex of echinoderms (Echinodermata) is composed of various primary and secondary body cavities that interact with each other. In sea urchins (Echinoidea), structural differences of the axial complex in "regular" and irregular species have been observed, but the reasons underlying these differences are not fully understood. In addition, a better knowledge of axial complex diversity could not only be useful for phylogenetic inferences, but improve also an understanding of the function of this enigmatic structure. Results We therefore analyzed numerous species of almost all sea urchin orders by magnetic resonance imaging, dissection, histology, and transmission electron microscopy and compared the results with findings from published studies spanning almost two centuries. These combined analyses demonstrate that the axial complex is present in all sea urchin orders and has remained structurally conserved for a long time, at least in the "regular" species. Within the Irregularia, a considerable morphological variation of the axial complex can be observed with gradual changes in topography, size, and internal architecture. These modifications are related to the growing size of the gastric caecum as well as to the rearrangement of the morphology of the digestive tract as a whole. Conclusion The structurally most divergent axial complex can be observed in the highly derived Atelostomata in which the reorganization of the digestive tract is most pronounced. Our findings demonstrate a structural interdependence of various internal organs, including digestive tract, mesenteries, and the axial complex. PMID:19508706

  7. Listado taxonómico de los equinodermos (Echinodermata: Asteroidea y Echinoidea) de la costa de Oaxaca en el Pacifico sur mexicano

    OpenAIRE

    Benítez-Villalobos, F.; Castillo-Lorenzano, E.; Gonzáles-Espinosa, G. S.

    2016-01-01

    Taxonomic list of the Echinoderms (Echinodermata: Asteroidea and Echinoidea) from the coast of Oaxaca in the south Pacific of Mexico. We present a systematic list of the echinoderms (Asteroidea, Echinoidea) from the coast of Oaxaca in the Southern Mexican Pacific, based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, National Museum of Natural History, Smithsonian Institution, Washington, D.C.,...

  8. Patterns and Drivers of Egg Pigment Intensity and Colour Diversity in the Ocean: A Meta-Analysis of Phylum Echinodermata.

    Science.gov (United States)

    Montgomery, E M; Hamel, J-F; Mercier, A

    Egg pigmentation is proposed to serve numerous ecological, physiological, and adaptive functions in egg-laying animals. Despite the predominance and taxonomic diversity of egg layers, syntheses reviewing the putative functions and drivers of egg pigmentation have been relatively narrow in scope, centring almost exclusively on birds. Nonvertebrate and aquatic species are essentially overlooked, yet many of them produce maternally provisioned eggs in strikingly varied colours, from pale yellow to bright red or green. We explore the ways in which these colour patterns correlate with behavioural, morphological, geographic and phylogenetic variables in extant classes of Echinodermata, a phylum that has close phylogenetic ties with chordates and representatives in nearly all marine environments. Results of multivariate analyses show that intensely pigmented eggs are characteristic of pelagic or external development whereas pale eggs are commonly brooded internally. Of the five egg colours catalogued, orange and yellow are the most common. Yellow eggs are a primitive character, associated with all types of development (predominant in internal brooders), whereas green eggs are always pelagic, occur in the most derived orders of each class and are restricted to the Indo-Pacific Ocean. Orange eggs are geographically ubiquitous and may represent a 'universal' egg pigment that functions well under a diversity of environmental conditions. Finally, green occurs chiefly in the classes Holothuroidea and Ophiuroidea, orange in Asteroidea, yellow in Echinoidea, and brown in Holothuroidea. By examining an unprecedented combination of egg colours/intensities and reproductive strategies, this phylum-wide study sheds new light on the role and drivers of egg pigmentation, drawing parallels with theories developed from the study of more derived vertebrate taxa. The primary use of pigments (of any colour) to protect externally developing eggs from oxidative damage and predation is

  9. from Pyura stolollifera (Echinodermata, Ascidiacea)

    African Journals Online (AJOL)

    1994-05-05

    May 5, 1994 ... The genus Doropygus has long been plagued by morphological and taxonomic confusion. Descriptions are often found to be inadequate and finer morphological variations result in laborious and unnecessary description of new species. Although the genus is known to be cosmopolitan in its distribution, ...

  10. Historical aspects of meetings, publication series, and digital resources dedicated to echinoderms

    Directory of Open Access Journals (Sweden)

    Alexander Ziegler

    2014-03-01

    Full Text Available Half a century after the first scientific meeting dedicated to marine spiny-skinned animals (Deuterostomia: Echinodermata was held in Washington, DC, we take this opportunity to provide information on a number of historical aspects related to the echinoderm scientific community. Apart from shedding light on the historical origins of modern echinoderm conferences, the present contribution presents photographs taken during the first meeting of echinoderm researchers in 1963 as well as during the first installments of the International Echinoderm Conference and the European Conference on Echinoderms. Furthermore, we provide background information on publication series dedicated solely to the Echinodermata as well as descriptions of selected digital resources that focus on echinoderms. Finally, we present a number of echinoderm conference logos and flyers in addition to selected information about specific echinoderm meetings.

  11. Melanopsin-mediated light-sensing in amphioxus: a glimpse of the microvillar photoreceptor lineage within the deuterostomia.

    Science.gov (United States)

    Nasi, Enrico; del Pilar Gomez, María

    2009-09-01

    The two fundamental lineages of photoreceptor cells, microvillar and ciliary, were long thought to be a prerogative of invertebrate and vertebrate organisms, respectively. However evidence of their ancient origin, preceding the divergence of these two branches of metazoa, suggests instead that they should be ubiquitously distributed. Melanopsin-expressing 'circadian' light receptors may represent the remnants of the microvillar photo- receptors amongst vertebrates, but they lack the characteristic architecture of this lineage, and much remains to be clarified about their signaling mechanisms. Hesse and Joseph cells of the neuronal tube of amphioxus (Branchiostoma fl.)-the most basal chordate extant-turn out to be depolarizing primary microvillar photoreceptors, that generate a melanopsin-initiated, PLC-dependent response to light, mobilizing internal Ca and increasing a membrane conductance selective to Na and Ca ions. As such, they represent a canonical instance of invertebrate-like visual cells in the chordate phylum.

  12. [Echinoderms (Echinodermata) of the Mexican Caribbean].

    Science.gov (United States)

    Laguarda-Figueras, Alfredo; Solis-Marín, Francisco A; Durán-González, Alicia; Ahearn, Cynthia Gust; Buitrón Sánchez, Blanca Estela; Torres-Vega, Juan

    2005-12-01

    A systematic list of the echinoderms of the Mexican Caribbean based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. This list reveals an important echinoderm biodiversity in the Mexican Caribbean, where five of the six echinoderm classes are represented. A total of 178 echinoderm species is recorded, distributed in 113 genera, 51 families and 22 orders. 30 new records for the Mexican Caribbean are presents: Crínoidea (three), Asteroidea (two), Ophiuroidea (eleven), Echinoidea (one), Holothuroidea (thirteen).

  13. [The echinoderms (Echinodermata) from El Salvador].

    Science.gov (United States)

    Enrique Barraza, José; Roberto Hasbún, Carlos

    2005-12-01

    A list of echinoderms from El Salvador (tropical eastern Pacific) is presented. The results were obtained from field surveys (between the years 2000 and 2004), the scarce literature sources, and Internet information. A total of 37 species and six genera are reported. The most abundant echinoderms in rocky shores were: Phataria unifascialis, Echinometra vanbrunti, Holothuria kefersteini, as well as Astropecten armatus in soft bottoms.

  14. (Copepoda, Notodelphyidae) from Pyura stolonifera (Echinodermata ...

    African Journals Online (AJOL)

    The genus Doropygus has long been plagued by morphological and taxonomic confusion. Descriptions are often lound to be inadequate and finer morphological variations result in laborious and unnecessary description of new species. Although the genus is known to be cosmopolitan in its distribution, only four species ...

  15. Holothurian (Echinodermata) Diversity in the Glorieuses Archipelago

    African Journals Online (AJOL)

    Ste Clotilde, La Réunion, France. Keywords: Holothuria, Glorieuses Islands, Western Indian Ocean, occurrence, diversity, coral reefs. Abstract—Due to their isolation, Eparses Islands provide a valuable opportunity to investigate biodiversity in the absence of anthropogenic influence. The Glorieuses. Archipelago forms part ...

  16. Holothurian (Echinodermata) Diversity in the Glorieuses Archipelago

    African Journals Online (AJOL)

    Keywords: Holothuria, Glorieuses Islands, Western Indian Ocean, occurrence, diversity, coral reefs. Abstract—Due to their isolation, Eparses Islands provide a valuable opportunity to investigate ... 10 species were collected on the slopes and 15 on the reef flats. Despite the limited ..... fishery in Australia's Great Barrier Reef.

  17. Phylogeography of Holothuria (Halodeima inornata Semper, 1868 (Echinodermata: Holothuroidea

    Directory of Open Access Journals (Sweden)

    Elba Prieto-Rios

    2014-10-01

    Full Text Available Genetic structure of the populations of H. inornata was evaluated and the barriers for genetic flux and historic processes were investigated. Samples were collected trying to cover the distribution range of the species, from Mexico to northern Perú. Based on COI sequences, 118 haplotypes from 220 specimens were detected; the differences between such haplotypes were due to 97 variable sites (21.41% of the 453 bp sequenced. A high haplotype diversity (h=0.979 and a moderate nucleotidic diversity were observed. The values of Fst, the exact test of population differentiation, and the molecular variance analysis (AMOVA were used in order to analyze the genetic differentiation. These analyses suggest the existence of two populations: northern, off the coasts of Sinaloa, Jalisco, Michoacán, Guerrero, and Oaxaca, and southern, off the coasts of Chiapas, El Salvador, Panamá and Perú. Historic events and oceanographic patterns may be the main factors determining dispersion and structure of Hi populations. It seems probable that the original population have extended first in the south and then northern. Besides, the split between these two populations may be due to several tectonic and oceanographic events constituting a barrier for H. inornata settling.

  18. [Echinoderms (Echinodermata) from the Gulf of California, Mexico].

    Science.gov (United States)

    Solís-Marín, Francisco A; Laguarda-Figueras, Alfredo; Durán-González, Alicia; Ahearn, Cynthia Gust; Torres Vega, Juan

    2005-12-01

    A systematic list of the echinoderms of the Gulf of California, based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. A total of 193 echinoderm species is recorded, distributed in 108 genera, 51 families and 19 orders. 12 new records for the Gulf of California are presented: Asteroidea (four), Ophiuroidea (three) and Holothuroidea (five).

  19. The holothurian (Echinodermata) diversity of the Glorieuses Islands ...

    African Journals Online (AJOL)

    Glorieuses archipelago is one of the Eparses Islands, French islands scattered in the Mozambique Channel (Western Indian Ocean). These isolated coral islands, without permanent human population, are important to evaluate the evolution of biodiversity without direct anthropogenic influence. Among several aims, the ...

  20. Species diversity in the cryptic abyssal holothurian Psychropotes longicauda (Echinodermata)

    Science.gov (United States)

    Gubili, Chrysoula; Ross, Elizabeth; Billett, David S. M.; Yool, Andrew; Tsairidis, Charalampos; Ruhl, Henry A.; Rogacheva, Antonina; Masson, Doug; Tyler, Paul A.; Hauton, Chris

    2017-03-01

    Despite the plethora of studies on swallow-water invertebrates, almost nothing is known about the evolution and population structure of deep-sea species at the global scale. The aim of this study was to assess phylogeographic patterns of a common and cosmopolitan, predominantly abyssal sea cucumber, Psychropotes longicauda, based on samples from the Atlantic, Southern, Indian and Pacific oceans. Sequences of the mitochondrial COI and 16S genes were analysed for 128 specimens of P. longicauda. In addition, temporal genetic variation was investigated at one site, the Porcupine Abyssal Plain, NE Atlantic Ocean over a period of 34 years. Two distinct lineages within the global distribution were identified. The sister clades probably could be classified as separate species based on the observed genetic divergence (>5.0%) and phylogenetic reconstruction with indications of a Southern Hemisphere origin. Moreover, significant population differentiation was detected between the North Atlantic and localities in both the Pacific and Indian oceans. No bathymetric structuring was detected among lineages. Temporal genetic shifts were detected in a time series of samples from 1977 to 2011. Our data confirm the previously suspected cryptic species diversity throughout the wide distributional range previously attributed to the single species P. longicauda. The presence of sympatric species in the North Pacific and Indian Oceans has been underestimated by previous morphological analyses. The differentiation at the population level detected in the main lineages among the four oceans could suggest restricted gene flow despite wide-scale dispersal potential of the species.

  1. Status and applications of echinoid (phylum echinodermata) toxicity test methods

    Energy Technology Data Exchange (ETDEWEB)

    Bay, S.; Burgess, R.; Nacci, D.

    1993-01-01

    The use of echinoderms for toxicity testing has focused primarily on sea urchins and sand dollars (Strongylocentrotus purpuratus, Arbacia punctulata, Lytechinus pictus, and Dendraster excentricus, for example). The status and relative sensitivity of various test methods are described. The most frequently used test methods consist of short-term exposures of sea urchin sperm or embryos; these tests can be easily conducted at all times of the year by using species with complementary spawning cycles or laboratory conditioned populations of a single species. Data from reference toxicant and effluent toxicity tests are summarized. Information on the precision and sensitivity of echinoid test methods are limited and preclude rigorous comparisons with other test methods. The available data indicate that the sensitivity and precision of these methods are comparable to short-term chronic methods for other marine invertebrates and fish. Recent application of the sperm test in toxicity identification evaluations (TIEs) and studies of effluent toxicity decay and sediment toxicity illustrate the versatility of this rapid (10 to 60 min exposure) test method. Embryo tests typically use a 48 to 96 h exposure period and measure the occurrence of embryo malformations. Most recent applications of the embryo test have been for the assessment of sediment elutriate toxicity. Adult echinoderms are not frequently used to assess effluent or receiving water toxicity. Recent studies have had success in using the adult life stage of urchins and sand dollars to assess the effects of contaminated sediment on growth, behavior, and bioaccumulation.

  2. Ophiuroidea (Echinodermata from coral reefs in the Mexican Pacific

    Directory of Open Access Journals (Sweden)

    Rebeca Granja Fernández

    2014-05-01

    Full Text Available There are numerous and important coral reefs in the Mexican Pacific, but scarce studies of brittle stars conducted in these ecosystems. In this regard, this work provides the first annotated checklist of brittle stars associated with coral communities and reefs in the Mexican Pacific and an illustrated key to identify the species. We also provide taxonomic descriptions, spatial and bathymetric distributions and some important remarks of the species. We report a total of 14 species of brittle stars belonging to nine genera and seven families. Ophiocnida hispida in Jalisco, Ophiophragmus papillatus in Guerrero, and Ophiothrix (Ophiothrix spiculata and Ophiactis simplex in Colima are new distribution records. The record of O. papillatus is remarkable because the species has not been reported since its description in 1940. The brittle stars collected in this study, represent 22.2% of the total species previously reported from the Mexican Pacific. Presently, anthropogenic activities on the coral reefs of the Mexican Pacific have increased, thus the biodiversity of brittle stars in these ecosystems may be threatened.

  3. Ophiuroidea (Echinodermata) from coral reefs in the Mexican Pacific

    OpenAIRE

    Rebeca Granja Fernández; María Dinorah Herrero Pérezrul; Ramón Andrés López Pérez; Luis Hernández; Fabián Rodríguez Zaragoza; Robert Wallace Jones; Rubén Pineda López

    2014-01-01

    Abstract There are numerous and important coral reefs in the Mexican Pacific, but scarce studies of brittle stars conducted in these ecosystems. In this regard, this work provides the first annotated checklist of brittle stars associated with coral communities and reefs in the Mexican Pacific and an illustrated key to identify the species. We also provide taxonomic descriptions, spatial and bathymetric distributions and some important remarks of the species. We report a total of 14 species of...

  4. Ophiuroidea (Echinodermata) from coral reefs in the Mexican Pacific

    Science.gov (United States)

    Granja–Fernández, Rebeca; Herrero-Pérezrul, María D.; López-Pérez, Ramón A.; Hernández, Luis; Rodríguez-Zaragoza, Fabián A.; Jones, Robert Wallace; Pineda-López, Rubén

    2014-01-01

    Abstract There are numerous and important coral reefs in the Mexican Pacific, but scarce studies of brittle stars conducted in these ecosystems. In this regard, this work provides the first annotated checklist of brittle stars associated with coral communities and reefs in the Mexican Pacific and an illustrated key to identify the species. We also provide taxonomic descriptions, spatial and bathymetric distributions and some important remarks of the species. We report a total of 14 species of brittle stars belonging to nine genera and seven families. Ophiocnida hispida in Jalisco, Ophiophragmus papillatus in Guerrero, and Ophiothrix (Ophiothrix) spiculata and Ophiactis simplex in Colima are new distribution records. The record of O. papillatus is remarkable because the species has not been reported since its description in 1940. The brittle stars collected in this study, represent 22.2% of the total species previously reported from the Mexican Pacific. Presently, anthropogenic activities on the coral reefs of the Mexican Pacific have increased, thus the biodiversity of brittle stars in these ecosystems may be threatened. PMID:24843284

  5. Biological results of the Snellius expedition : XXIX. Echinodermata, Asteroidea

    NARCIS (Netherlands)

    Jangoux, M.

    1978-01-01

    Twenty-eight species of starfish were collected during the Snellius Expedition (19291930). The collection contains seven rare or uncommon species, i.e., Astropecten novaeguineae, A. sumbawanus, Celerina heffernani, Fromia eusticha, Disasterina abnormalis, Nepanthia briareus and Echinaster

  6. Antarctic Starfish (Echinodermata, Asteroidea) from the ANDEEP3 expedition

    Science.gov (United States)

    Danis, Bruno; Jangoux, Michel; Wilmes, Jennifer

    2012-01-01

    Abstract This dataset includes information on sea stars collected during the ANDEEP3 expedition, which took place in 2005. The expedition focused on deep-sea stations in the Powell Basin and Weddell Sea. Sea stars were collected using an Agassiz trawl (3m, mesh-size 500µm), deployed in 16 stations during the ANTXXII/3 (ANDEEP3, PS72) expedition of the RV Polarstern. Sampling depth ranged from 1047 to 4931m. Trawling distance ranged from 731 to 3841m. The sampling area ranges from -41°S to -71°S (latitude) and from 0 to -65°W (longitude). A complete list of stations is available from the PANGAEA data system (http://www.pangaea.de/PHP/CruiseReports.php?b=Polarstern), including a cruise report (http://epic-reports.awi.de/3694/1/PE_72.pdf). The dataset includes 50 records, with individual counts ranging from 1-10, reaching a total of 132 specimens. The andeep3-Asteroidea is a unique dataset as it covers an under-explored region of the Southern Ocean, and that very little information was available regarding Antarctic deep-sea starfish. Before this study, most of the information available focused on starfish from shallower depths than 1000m. This dataset allowed to make unique observations, such as the fact that some species were only present at very high depths (Hymenaster crucifer, Hymenaster pellucidus, Hymenaster praecoquis, Psilaster charcoti, Freyella attenuata, Freyastera tuberculata, Styrachaster chuni and Vemaster sudatlanticus were all found below -3770m), while others displayed remarkable eurybathy, with very high depths amplitudes (Bathybiaster loripes (4842m), Lysasterias adeliae (4832m), Lophaster stellans (4752m), Cheiraster planeta (4708m), Eremicaster crassus (4626m), Lophaster gaini (4560m) and Ctenodiscus australis (4489m)). Even if the number of records is relatively small, the data bring many new insights on the taxonomic, bathymetric and geographic distributions of Southern starfish, covering a very large sampling zone. The dataset also brings to light six species, newly reported in the Southern Ocean. The quality of the data was controlled very thoroughly, by means of on-board Polarstern GPS systems, checking of identification by a renowned specialist (Prof. Michel Jangoux, Université Libre de Bruxelles), and matching to the Register of Antarctic Marine Species (RAMS) and World Register of Marine Species (WoRMS). The data is therefore fit for completing checklists, for inclusion in biodiversity patterns analysis, or niche modeling. It also nicely fills an information gap regarding deep-sea starfish from the Southern Ocean, for which data is very scarce at this time. The authors may be contacted if any additional information is needed before carrying out detailed biodiversity or biogeographic studies. PMID:22577314

  7. Recent distribution of Echinodermata species in Spitsbergen coastal waters

    Directory of Open Access Journals (Sweden)

    Deja Kajetan

    2016-12-01

    Full Text Available Thirty-two species of echinoderms from epibenthic sledges, dredges, scuba diving, and other samples (in total: 467 samples and c. 20 000 specimens from fjords and coastal waters off Spitsbergen were analysed between 1996 and 2014. The most numerous group of echinoderms in the coastal waters off Spitsbergen is brittle stars (78% of the total individuals. The echinoderms do not form any clear assemblages according to depth or distance from glacial sedimentation and substrate. Some species prefer hard bottom (Strongylocentrotus droebachiensis or water free from glacial suspensions (Ophiopholis aculeata. In contrast to the species listed above, we also found opportunistic species such as the starfish Urasterias lincki and the brittle star Ophiocten sericeum. These two species are distributed quite uniformly, regardless of the environmental factors. The majority of the species prefer a soft bottom below 200 m.

  8. Antarctic Starfish (Echinodermata, Asteroidea from the ANDEEP3 expedition

    Directory of Open Access Journals (Sweden)

    Bruno Danis

    2012-04-01

    Full Text Available This dataset includes information on sea stars collected during the ANDEEP3 expedition, which took place in 2005. The expedition focused on deep-sea stations in the Powell Basin and Weddell Sea.Sea stars were collected using an Agassiz trawl (3m, mesh-size 500µm, deployed in 16 stations during the ANTXXII/3 (ANDEEP3, PS72 expedition of the RV Polarstern. Sampling depth ranged from 1047 to 4931m. Trawling distance ranged from 731 to 3841m. The sampling area ranges from -41°S to -71°S (latitude and from 0 to -65°W (longitude. A complete list of stations is available from the PANGAEA data system (http://www.pangaea.de/PHP/CruiseReports.php?b=Polarstern, including a cruise report (http://epic-reports.awi.de/3694/1/PE_72.pdf.The dataset includes 50 records, with individual counts ranging from 1-10, reaching a total of 132 specimens.The andeep3-Asteroidea is a unique dataset as it covers an under-explored region of the Southern Ocean, and that very little information was available regarding Antarctic deep-sea starfish. Before this study, most of the information available focused on starfish from shallower depths than 1000m. This dataset allowed to make unique observations, such as the fact that some species were only present at very high depths (Hymenaster crucifer, Hymenaster pellucidus, Hymenaster praecoquis, Psilaster charcoti, Freyella attenuata, Freyastera tuberculata, Styrachaster chuni and Vemaster sudatlanticus were all found below -3770m, while others displayed remarkable eurybathy, with very high depths amplitudes (Bathybiaster loripes (4842m, Lysasterias adeliae (4832m, Lophaster stellans (4752m, Cheiraster planeta (4708m, Eremicaster crassus (4626m, Lophaster gaini (4560m and Ctenodiscus australis (4489m.Even if the number of records is relatively small, the data bring many new insights on the taxonomic, bathymetric and geographic distributions of Southern starfish, covering a very large sampling zone. The dataset also brings to light six species, newly reported in the Southern Ocean.The quality of the data was controlled very thoroughly, by means of on-board Polarstern GPS systems, checking of identification by a renowned specialist (Prof. Michel Jangoux, Université Libre de Bruxelles, and matching to the Register of Antarctic Marine Species (RAMS and World Register of Marine Species (WoRMS. The data is therefore fit for completing checklists, for inclusion in biodiversity patterns analysis, or niche modeling. It also nicely fills an information gap regarding deep-sea starfish from the Southern Ocean, for which data is very scarce at this time. The authors may be contacted if any additional information is needed before carrying out detailed biodiversity or biogeographic studies.

  9. NEW TRIASSIC ASTEROIDEA (ECHINODERMATA SPECIMENS AND THEIR EVOLUTIONARY SIGNIFICANCE

    Directory of Open Access Journals (Sweden)

    DANIEL B. BLAKE

    2017-04-01

    Full Text Available The Paleozoic-Mesozoic transition saw the disappearance of asteroid stem groups and the ascent of the crown group, but late Paleozoic and Triassic asteroids are rare and transition events are poorly documented. Three new Middle and Late Triassic specimens augment existing data; included are a specimen of Trichasteropsis weissmanni from Germany, a specimen of Trichasteropsis? sp. indet. from Italy, and a possible member of the extant Poraniidae from Slovenia. Presence of a small ossicle at the interbrachial midline and adjacent to the marginal series of the new T. weissmanni specimen is consistent with similar expressions not only of other trichasteropsids but also occurrence of two interbrachial ossicles in Paleozoic, stem-group asterozoans; presence is in turn consistent with a hypothesis of derivation of the axillary/odontophore coupling from two ossicles rather than direct derivation of the crown-group odontophore from a single stem-group axillary. Morphology of Trichasteropsis? sp. indet., including, for example, the evenly-tapering arms are reminiscent of those of diverse crown-group asteroids whereas the enlarged distal arms of T. weissmanni are unique, the morphology of T? sp. indet. thereby potentially indicative of a plesiomorphic, stemward positioning within the Trichasteropsiidae. The range of the Poraniidae is tentatively extended to the Carnian. Similarities shared by the Poraniidae and the Trichasteropsiidae suggest stemward positioning within crown-group diversification; however, known Triassic fossils do not appear closely related to extant taxa identified in recent molecular studies as basal within the crown-group. A temperate climate is suggested as preferred by the Triassic asteroids rather than a tropical, warmer one.

  10. Systematics and zoogeography of Asteroidea (Echinodermata) from Inhaca Island, Mozambique

    NARCIS (Netherlands)

    Walenkamp, J.H.C.

    1990-01-01

    Sixteen out of the seventeen species of shallow-water starfishes reported with certainty from Inhaca Island and Maputo Bay were collected by the author. The seventeenth, Archaster angulatus, was recorded from there by Jangoux (1973). An identification key to these species, both in English and in

  11. Seasonal changes in biochemical composition of Holothuria leucospilota (Echinodermata)

    Digital Repository Service at National Institute of Oceanography (India)

    Jayasree, V.; Parulekar, A.H.; Wahidullah, S.; Kamat, S.Y.

    Biochemical composition of body wall and gonads of Holothuria leucospilota was analysed for protein, carbohydrate, lipid, ash, dry weight and calorific values and was discussed in relation to its spawning activities. Lipids constituted the major...

  12. Antarctic Starfish (Echinodermata, Asteroidea) from the ANDEEP3 expedition.

    Science.gov (United States)

    Danis, Bruno; Jangoux, Michel; Wilmes, Jennifer

    2012-01-01

    This dataset includes information on sea stars collected during the ANDEEP3 expedition, which took place in 2005. The expedition focused on deep-sea stations in the Powell Basin and Weddell Sea.Sea stars were collected using an Agassiz trawl (3m, mesh-size 500µm), deployed in 16 stations during the ANTXXII/3 (ANDEEP3, PS72) expedition of the RV Polarstern. Sampling depth ranged from 1047 to 4931m. Trawling distance ranged from 731 to 3841m. The sampling area ranges from -41°S to -71°S (latitude) and from 0 to -65°W (longitude). A complete list of stations is available from the PANGAEA data system (http://www.pangaea.de/PHP/CruiseReports.php?b=Polarstern), including a cruise report (http://epic-reports.awi.de/3694/1/PE_72.pdf).The dataset includes 50 records, with individual counts ranging from 1-10, reaching a total of 132 specimens.The andeep3-Asteroidea is a unique dataset as it covers an under-explored region of the Southern Ocean, and that very little information was available regarding Antarctic deep-sea starfish. Before this study, most of the information available focused on starfish from shallower depths than 1000m. This dataset allowed to make unique observations, such as the fact that some species were only present at very high depths (Hymenaster crucifer, Hymenaster pellucidus, Hymenaster praecoquis, Psilaster charcoti, Freyella attenuata, Freyastera tuberculata, Styrachaster chuni and Vemaster sudatlanticus were all found below -3770m), while others displayed remarkable eurybathy, with very high depths amplitudes (Bathybiaster loripes (4842m), Lysasterias adeliae (4832m), Lophaster stellans (4752m), Cheiraster planeta (4708m), Eremicaster crassus (4626m), Lophaster gaini (4560m) and Ctenodiscus australis (4489m)).Even if the number of records is relatively small, the data bring many new insights on the taxonomic, bathymetric and geographic distributions of Southern starfish, covering a very large sampling zone. The dataset also brings to light six species, newly reported in the Southern Ocean.The quality of the data was controlled very thoroughly, by means of on-board Polarstern GPS systems, checking of identification by a renowned specialist (Prof. Michel Jangoux, Université Libre de Bruxelles), and matching to the Register of Antarctic Marine Species (RAMS) and World Register of Marine Species (WoRMS). The data is therefore fit for completing checklists, for inclusion in biodiversity patterns analysis, or niche modeling. It also nicely fills an information gap regarding deep-sea starfish from the Southern Ocean, for which data is very scarce at this time. The authors may be contacted if any additional information is needed before carrying out detailed biodiversity or biogeographic studies.

  13. Ophiuroidea (Echinodermata: quatro novas ocorrências para o Brasil Ophiuroidea (Echinodermata: four new records for Brazil

    Directory of Open Access Journals (Sweden)

    Michela Borges

    2007-12-01

    Full Text Available Os ofiuróides aqui analisados são procedentes dos programas "Biodiversidade Bêntica Marinha no Estado de São Paulo" - BIOTA/FAPESP-Bentos Marinhos, "Avaliação do Potencial Sustentável dos Recursos Vivos da Zona Econômica Exclusiva" - REVIZEE/Score Sul-Bentos e "Utilização Racional dos Ecossistemas Costeiros da Região Tropical Brasileira: Estado de São Paulo" - INTEGRADO/Subprojeto Bentos. As amostras analisadas foram coletadas nas regiões da plataforma e talude continental do Sudeste e Sul brasileiros, em profundidades entre 10 e 800 m. São aqui descritas e ilustradas quatro espécies de Ophiuroidea, as quais representam novos registros de ocorrência para o Brasil, duas da família Ophiuridae, uma de Amphiuridae e uma de Ophiochitonidae. Este é também o primeiro registro desta última família para o Brasil. Somente Amphiodia trychna (Amphiuridae foi amostrada na região da plataforma interna (profundidade The ophiuroids were collected during the Programs "Biodiversidade Bêntica Marinha no Estado de São Paulo" - BIOTA/FAPESP-Marine Benthos, "Avaliação do Potencial Sustentável dos Recursos Vivos da Zona Econômica Exclusiva" - REVIZEE/Score South - Benthos and "Utilização Racional dos Ecossistemas Costeiros da Região Tropical Brasileira: Estado de São Paulo" - INTEGRADO/Subproject Benthos. Samples were obtained from the continental shelf and slope off southeast and south Brazil, between 10 and 800 m. Four species of the Ophiuroidea are described and they are new records for Brazil. Two species belong to the family Ophiuridae, and the others belong to Amphiuridae and Ophiochitonidae. The family Ophiochitonidae is recorded for the first time in Brazil. Amphiodia trychna (Amphiuridae was sampled in the inner continental shelf (depth < 50 m. The other three species were collected deeper (between 314 and 808 m.

  14. A detailed description of the development of the hemichordate Saccoglossus kowalevskii using SEM, TEM, Histology and 3D-reconstructions.

    Science.gov (United States)

    Kaul-Strehlow, Sabrina; Stach, Thomas

    2013-09-06

    Traditionally, the origin of the third germ layer and its special formation of coelomic cavities by enterocoely is regarded to be an informative character in phylogenetic analyses. In early deuterostomes such as sea urchins, the mesoderm forms through a single evagination pinching off from the apical end of the archenteron which then gives off mesocoela and metacoela on each side. This echinoid-type coelom formation has conventionally been assumed to be ancestral for Deuterostomia. However, recent phylogenetic analyses show that Echinodermata hold a more derived position within Deuterostomia. In this regard a subgroup of Hemichordata, namely enteropneusts, seem to host promising candidates, because they are supposed to have retained many ancestral deuterostome features on the one hand, and furthermore share some characteristics with chordates on the other hand. In enteropneusts a wide range of different modes of coelom formation has been reported and in many cases authors of the original observations carefully detailed the limitations of their descriptions, while these doubts disappeared in subsequent reviews. In the present study, we investigated the development of all tissues in an enteropneust, Saccoglossus kowalevskii by using modern morphological techniques such as complete serial sectioning for LM and TEM, and 3D-reconstructions, in order to contribute new data to the elucidation of deuterostome evolution. Our data show that in the enteropneust S. kowalevskii all main coelomic cavities (single protocoel, paired mesocoela and metacoela) derive from the endoderm via enterocoely as separate evaginations, in contrast to the aforementioned echinoid-type. The anlagen of the first pair of gill slits emerge at the late kink stage (~96 h pf). From that time onwards, we documented a temporal left-first development of the gill slits and skeletal gill rods in S. kowalevskii until the 2 gill slit juvenile stage. The condition of coelom formation from separate

  15. Invertebrates as model organisms for research on aging biology.

    Science.gov (United States)

    Murthy, Mahadev; Ram, Jeffrey L

    2015-01-30

    Invertebrate model systems, such as nematodes and fruit flies, have provided valuable information about the genetics and cellular biology involved in aging. However, limitations of these simple, genetically tractable organisms suggest the need for other model systems, some of them invertebrate, to facilitate further advances in the understanding of mechanisms of aging and longevity in mammals, including humans. This paper introduces 10 review articles about the use of invertebrate model systems for the study of aging by authors who participated in an 'NIA-NIH symposium on aging in invertebrate model systems' at the 2013 International Congress for Invertebrate Reproduction and Development. In contrast to the highly derived characteristics of nematodes and fruit flies as members of the superphylum Ecdysozoa, cnidarians, such as Hydra, are more 'basal' organisms that have a greater number of genetic orthologs in common with humans. Moreover, some other new model systems, such as the urochordate Botryllus schlosseri, the tunicate Ciona, and the sea urchins (Echinodermata) are members of the Deuterostomia, the same superphylum that includes all vertebrates, and thus have mechanisms that are likely to be more closely related to those occurring in humans. Additional characteristics of these new model systems, such as the recent development of new molecular and genetic tools and a more similar pattern to humans of regeneration and stem cell function suggest that these new model systems may have unique advantages for the study of mechanisms of aging and longevity.

  16. Los equinodermos (Echinodermata de bahía Chamela, Jalisco, México The echinoderms (Echinodermata from bahía Chamela, Jalisco, Mexico

    Directory of Open Access Journals (Sweden)

    Eduardo Ríos-Jara

    2013-03-01

    Full Text Available Cuarenta especies de equinodermos fueron recolectadas en las zonas intermareal y submareal somero de 14 sitios de bahía Chamela. Destacan 7 nuevos registros para la costa de Jalisco. Los análisis de escalonamiento multidimensional no métrico y el índice de similitud de Jaccard permitieron identificar grupos y entidades aisladas de acuerdo a la contribución y frecuencia de las especies de 4 clases de equinodermos en los sitios de la bahía y en otras localidades del Pacífico tropical mexicano (PTM. La mayor similitud se presentó con las localidades del golfo de California. Los índices de distinción taxonómica promedio (Δ+ y su variación (Λ+ fueron utilizados para analizar la diversidad de equinodermos en los niveles de especie, género, familia, orden y clase para cada sitio de la bahía y para distintas localidades del PTM de acuerdo al número de jerarquías taxonómicas de alto orden y la variabilidad en su diversidad taxonómica. La riqueza de especies de Chamela representa el 20% de la diversidad total de equinodermos de las zonas intermareal y submareal somero del PTM, lo que indica su importancia en la contribución a la diversidad taxonómica de la región.Forty species of echinoderms were collected in the intertidal and shallow subtidal zones of 14 sites of bahía Chamela. Of particular importance are 7 new records of species for the coast of Jalisco. A nonmetric multidimensional scaling analysis and the Jaccard's similarity index identified different groups and isolated entities according to the contribution and the frequency of species of 4 classes of echinoderms in the bay and in other localities of the Mexican Tropical Pacific (MTP. The highest similarity of species was with the localities of the Gulf of California. The indices of average taxonomic distinctness (Δ+ and the variation in the taxonomic distinctness (Λ+ were estimated to analyze the diversity of echinoderms at the taxonomic levels of species, genus, family, order and class for each site within the bay and for some localities of the MTP according to the number of higher taxonomic hierarchies and the variability of its taxonomic diversity. The species richness of bahía Chamela represents 20% of the total diversity of echinoderms of the intertidal and shallow subtidal zones of the MTP; this is an indicator of its importance to the contribution of the taxonomic diversity of this region.

  17. The sequence of origin of the postmetamorphic rays in Heliaster and Labidiaster (Echinodermata: Asteroidea Origen sequencial de los rayos postmetamorficos en Heliaster y Labidiaster (Echinodermata: Asteroidea

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    PATRICIO SANCHEZ R

    2000-12-01

    Full Text Available Postmetamorphic rays in Heliaster and Labidiaster originate in four `quadrants' between the five primary rays, and not normally in the madreporic interradius. The rays originate in one of two very definite sequences depending on the species. H. kubiniji and H. multiradiatus share one sequence, whereas H. canopus, H. helianthus and Labidiaster share the other sequence. Pycnopodia, Rathbunaster, Heliaster and Labidiaster add rays at far greater sizes and in a manner that is distinctive from other multiradiate starfish, possibly indicating a new taxonomic unitLos rayos post-metamórficos en Heliaster y Labidiaster se originan en cuatro"cuadrantes" entre los cinco rayos primarios, y no como ocurre normalmente en el interradio del madreporito. Los rayos se originan en una de dos secuencias definidas, dependiendo de la especie. H. kubiniji y H. multiradiatus comparten una secuencia, mientras que H. canopus, H. helianthus y Labidiaster comparten otra secuancia. Pycnopodia, Rathbunaster, Heliaster y Labidiaster adicional rayos de tamaños mucho mayores y de una manera que es distintiva de aquel de otras estrellas de mar multiradiadas, posiblemente indicando su pertenencia a una nueva unidad taxonómica

  18. First record of Lissothuria antillensis (Echinodermata: Holothuroidea from the Gulf of Mexico Primer registro de Lissothuria antillensis (Echinodermata:Holothuroidea en el golfo de México

    Directory of Open Access Journals (Sweden)

    Julio Adrián Arriaga-Ochoa

    2012-03-01

    Full Text Available Two specimens of Lissothuria antillensis Pawson, 1967 were collected at 2 localities from the Gulf of Mexico, Isla Verde and Tuxpan Reef, Veracruz, Mexico. This species had been reported previously only from the Caribbean Sea.Dos ejemplares de Lissothuria antillensis Pawson, 1967 fueron capturados en 2 localidades del golfo de México, en Isla Verde, Veracruz y en el arrecife de Tuxpan, Veracruz, México. Esta especie ha sido registrada anteriormente sólo para el mar Caribe.

  19. First record of Lissothuria antillensis (Echinodermata: Holothuroidea) from the Gulf of Mexico Primer registro de Lissothuria antillensis (Echinodermata:Holothuroidea) en el golfo de México

    OpenAIRE

    Julio Adrián Arriaga-Ochoa; Francisco Alonso Solis-Marin; Alfredo?Laguarda-Figueras,; Vivianne Solis-Weiss

    2012-01-01

    Two specimens of Lissothuria antillensis Pawson, 1967 were collected at 2 localities from the Gulf of Mexico, Isla Verde and Tuxpan Reef, Veracruz, Mexico. This species had been reported previously only from the Caribbean Sea.Dos ejemplares de Lissothuria antillensis Pawson, 1967 fueron capturados en 2 localidades del golfo de México, en Isla Verde, Veracruz y en el arrecife de Tuxpan, Veracruz, México. Esta especie ha sido registrada anteriormente sólo para el mar Caribe.

  20. Bioactive substances with anti-neoplastic efficacy from marine invertebrates: Bryozoa, Mollusca, Echinodermata and Urochordata

    OpenAIRE

    Sima, Peter; Vetvicka, Vaclav

    2011-01-01

    The marine environment provides a rich source of natural products with potential therapeutic application. This has resulted in an increased rate of pharmaceutical agents being discovered in marine animals, particularly invertebrates. Our objective is to summarize the most promising compounds which have the best potential and may lead to use in clinical practice, show their biological activities and highlight the compounds currently being tested in clinical trials. In this paper, we focused on...

  1. Histamine is a modulator of metamorphic competence in Strongylocentrotus purpuratus (Echinodermata: Echinoidea)

    Science.gov (United States)

    2012-01-01

    Background A metamorphic life-history is present in the majority of animal phyla. This developmental mode is particularly prominent among marine invertebrates with a bentho-planktonic life cycle, where a pelagic larval form transforms into a benthic adult. Metamorphic competence (the stage at which a larva is capable to undergo the metamorphic transformation and settlement) is an important adaptation both ecologically and physiologically. The competence period maintains the larval state until suitable settlement sites are encountered, at which point the larvae settle in response to settlement cues. The mechanistic basis for metamorphosis (the morphogenetic transition from a larva to a juvenile including settlement), i.e. the molecular and cellular processes underlying metamorphosis in marine invertebrate species, is poorly understood. Histamine (HA), a neurotransmitter used for various physiological and developmental functions among animals, has a critical role in sea urchin fertilization and in the induction of metamorphosis. Here we test the premise that HA functions as a developmental modulator of metamorphic competence in the sea urchin Strongylocentrotus purpuratus. Results Our results provide strong evidence that HA leads to the acquisition of metamorphic competence in S. purpuratus larvae. Pharmacological analysis of several HA receptor antagonists and an inhibitor of HA synthesis indicates a function of HA in metamorphic competence as well as programmed cell death (PCD) during arm retraction. Furthermore we identified an extensive network of histaminergic neurons in pre-metamorphic and metamorphically competent larvae. Analysis of this network throughout larval development indicates that the maturation of specific neuronal clusters correlates with the acquisition of metamorphic competence. Moreover, histamine receptor antagonist treatment leads to the induction of caspase mediated apoptosis in competent larvae. Conclusions We conclude that HA is a modulator of metamorphic competence in S. purpuratus development and hypothesize that HA may have played an important role in the evolution of settlement strategies in echinoids. Our findings provide novel insights into the evolution of HA signalling and its function in one of the most important and widespread life history transitions in the animal kingdom - metamorphosis. PMID:22541006

  2. Holothuria (Selenkothuria) parvispinea n. sp. (Echinodermata, Hololthuroidea, Holothuriidae) with key to the sub-genus Selenkothuria.

    Science.gov (United States)

    Massin, Claude

    2013-01-30

    Description of a new species from Australia, belonging to the subgenus Selenkothuria (Holothuria, Aspidochirotida). A dichotomous key of the thirteen valid species included in the subgenus is also given. The species H. perrieri Thandar, 1977 and H. spinea Cherbonnier, 1988 are considered as non valid.

  3. An occurence records database of Irregular Echinoids (Echinodermata: Echinoidea) in Mexico.

    Science.gov (United States)

    Martínez-Melo, Alejandra; Solís-Marín, Francisco Alonso; Buitrón-Sánchez, Blanca Estela; Laguarda-Figueras, Alfredo

    2016-01-01

    Research on echinoderms in Mexico began in the late nineteenth century. We present a dataset that includes the taxonomic and geographic information of irregular echinoids from Mexico, housed in four collections: 1) Colección Nacional de Equinodermos "Ma. Elena Caso Muñoz" from the Instituto de Ciencias del Mar y Limnología (ICML), Universidad Nacional Autónoma de México (UNAM); 2) Invertebrate Zoology Collection, Smithsonian Museum of Natural History, Washington, D.C., United States of America (USA); 3) Invertebrate Collection, Museum of Comparative Zoology, University of Harvard, Boston, Massachusetts, USA and 4) Invertebrate Zoology, Peabody Museum, Yale University, New Haven, Connecticut, USA. A total of six orders, 17 families, 35 genera and 68 species are reported, 37 distributed in the Pacific coast and 31 in the Atlantic coast, none of them was found in both coasts. The most diverse region is the Gulf of California (S=32); the most diverse order is Spatangoida with 31 species reported in mexican waters.

  4. Ultrastructural evidence of the excretory function in the asteroid axial organ (Asteroidea, Echinodermata).

    Science.gov (United States)

    Ezhova, O V; Egorova, E A; Malakhov, V V

    2016-05-01

    The ultrastructure of the axial organ of Asterias amurensis has been studied The organ is a network of canals of the axial coelom separated by haemocoelic spaces. The axial coelom is lined with two types of monociliary cells: podocytes and musculo-epithelial cells. Podocytes form numerous basal processes adjacent to the basal lamina on the coelomic side. Musculo-epithelial cells form processes running along the basal lamina. Some bundles of these processes wrapped in the basal lamina pass through haemocoelic spaces between neighboring coelomic canals. It is hypothesized that the axial organ serves for filtration of fluid from haemocoelic spaces into the axial coelom cavity, from which urine is excreted through the madreporite to the exterior.

  5. The basiepithelial nerve plexus of the viscera and coelom of eleutherozoan Echinodermata.

    Science.gov (United States)

    Cobb, J L; Raymond, A M

    1979-10-02

    The organisation of the basiepithelial nerve plexus in the alimentary canal of a starfish and the water vascular system of a sea-urchin is described. The plexus contains varicose aminergic neurones which terminate adjacent to the ciliated epithelial cells. It is proposed that the basiepithelial plexus innervates these cells and controls ciliary beating. The distribution of the basiepithelial plexus in various tissues described by other workers is discussed particularly in relation to whether it is the coelomic epithelium or the luminal epithelium which is innervated. It is concluded that where there is both an endothelium and a coelomic epithelium only one is innervated. The muscles, where present, of the viscera are innervated by a separate nervous system. The muscles are always on the opposite side of the non-cellular connective tissue sheath to the basiepithelial plexus.

  6. Ultrastructure of the Coeloms of Auricularia Larvae (Holothuroidea: Echinodermata): Evidence for the Presence of an Axocoel.

    Science.gov (United States)

    Balser, E J; Ruppert, E E; Jaeckle, W B

    1993-08-01

    A hallmark feature of echinoderm larvae is the development of the left anterior coelom. This coelom, called the axohydrocoel, consists of the morphologically distinct, but undivided, left axocoel and hydrocoel. The axocoelic portion forms a duct that opens to the exterior via a pore on the dorsal surface of the animal. Holothuroid larvae are thought to lack an axocoel, but develop an anterior coelom, duct, and pore that are regarded as parts of the hydrocoel. New ultrastructural data, however, show that holothuroid auricularia larvae possess an axocoel and hydrocoel united together into an axohydrocoel. During development the anterior coelom consists of an interconnected left somatocoel, hydrocoel, and axocoel. The left somatocoel separates from the axohydrocoel and subdivides into left and right somatocoels. The somatocoels and hydrocoel region of the axohydrocoel are lined by a monociliated mesothelium having characteristics of transporting epithelia. The axocoel epithelium, like that of asteroid larvae, is composed of mesothelial podocytes. A duct connects the axocoel directly to the open dorsal pore and is lined with a columnar transporting epithelium. The occurrence of a specialized podocyte-lined cavity between the surface pore and the hydrocoel in echinoderm larvae is indicative of an axocoel. That similar structures occur in auricularia larvae supports the identification of an axocoel in holothuroids.

  7. Avoidance of crude-oil contaminated sediment by the Australian seastar, Patiriella exigua (Echinodermata: Asteroidea)

    Energy Technology Data Exchange (ETDEWEB)

    Ryder, K. [RMIT University, Victoria (Australia). Department of Biotechnology and Environmental Biology; Temara, A. [RMIT University, Victoria (Australia). Department of Biotechnology and Environmental Biology; Procter and Gamble, Environmental Safety (Belgium); Holdway, D.A. [RMIT University, Victoria (Australia). Department of Biotechnology and Environmental Biology; University of Ontario Institute of Technology, Oshawa, Ont. (Canada). Faculty of Science

    2004-12-01

    This study attempted to determine whether Patiriella exigua, an Australian seastar, could detect and/or avoid oiled sediment when given an equal choice of unoiled sediment. The sediment was spiked once to produce one of three concentrations of oiled sediment used in the test chambers versus unoiled sediment. Behavioral observations were repeated over a 32 day period to test the effects of aging the oiled sediment. Results show that Patiriella exigua was capable of detecting oiled sediment and/or an oiled environment. Seastars avoided oiled sediment, with significantly higher numbers choosing either to reside on the clean sediment (p<0.05) or to travel up the glass sides of the tanks (p<0.0001). Avoidance of oiled sediment increased with increasing sediment oil concentrations. Aging the oiled sediment decreased the oil content of the sediment and increased the number of seastars able to inhabit it (p<0.001). A potential narcotic effect of exposure to oiled sediment was observed. (author)

  8. [Echinoderms (Echinodermata) from the Mexican waters of the Gulf of Mexico].

    Science.gov (United States)

    Durán-González, Alicia; Laguarda-Figueras, Alfredo; Solís-Marin, Francisco A; Buitrón Sánchez, Blanca Estela; Ahearn, Cynthia Gust; Torres-Vega, Juan

    2005-12-01

    We present a systematic list of the echinoderms from Gulf of Mexico's Mexican waters based on specimens of the Colecci6n Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Aut6noma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. This list reveals an important echinoderm biodiversity present in the Gulf of Mexico, where five of the six echinoderm classes are represented. A total of 209 echinoderm species is recorded, distributed in 129 genera, 63 families and 25 orders. 31 new records for the Gulf of Mexico are presented: Asteroidea (16), Ophiuroidea (nine), Echinoidea (one) and Holothuroidea (five).

  9. A field guide to the Silurian Echinodermata of the British Isles: Part 1 - Eleutherozoa and Rhombifera

    NARCIS (Netherlands)

    Lewis, D.N.; Donovan, S.K.; Crabb, P.; Gladwell, D.J.

    2007-01-01

    The Palaeozoic echinoderms of the British Isles are most diverse in the Silurian and Lower Carboniferous. This guide discusses and illustrates members of all major groups of echinoderms, apart from the crinoids, from the Silurian of these islands. Groups considered include the echinoids (five taxa),

  10. Echinodermata das praias de Salvador (Bahia, Brasil The Echinoderms of Salvador beaches (Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Orane Falcão de Souza Alves

    2000-06-01

    Full Text Available This paper presents 28 species of Echinoderms collected on 5 beaches of Salvador (12º54' to 13º01' S and 38º26' to 38º33' W, Brazil, which are distributed in 19 families. Ophiuroidea represented 53,6% of the collected species, followed by Echinoidea (28,6%, Asteroidea (7,1%, Holothuroidea (7,1%, and Crinoidea (3,6%. Ophiuroidea and Echinoidea were the most frequent groups, occurring at all the studied beaches while Crinoidea occurred only on 20% of them. Most of the species are characterized as belonging to the tropical warm waters, some to the shallow coastal areas and some having a broad bathymetric distribution. The richness of species values on beaches ranged from 7 to 24, at Itapua Beach, and from 2 to 14 among different kinds of habitats, where protected ones showed higher values.

  11. Phylogenomic Analyses of Echinodermata Support the Sister Groups of Asterozoa and Echinozoa

    OpenAIRE

    Reich, Adrian; Dunn, Casey; Akasaka, Koji; Wessel, Gary

    2015-01-01

    Echinoderms (sea urchins, sea stars, brittle stars, sea lilies and sea cucumbers) are a group of diverse organisms, second in number within deuterostome species to only the chordates. Echinoderms serve as excellent model systems for developmental biology due to their diverse developmental mechanisms, tractable laboratory use, and close phylogenetic distance to chordates. In addition, echinoderms are very well represented in the fossil record, including some larval features, making echinoderms...

  12. Diversity of the Holothuroid Fauna (Echinodermata) at La Réunion ...

    African Journals Online (AJOL)

    Echinoderms are conspicuous components of the tropical fauna and play important roles in the functioning of coral reefs. However, their diversity is not as well documented as that of other conspicuous reef organisms such as corals or fish. We review current knowledge of the diversity of the class Holothuroidea at La ...

  13. Planktonic dispersal of juvenile brittle stars (Echinodermata: Ophiuroidea) on a Caribbean reef

    National Research Council Canada - National Science Library

    Hendler, Gordon; Baldwin, Carole C; Smith, David G; Thacker, Christine E

    1999-01-01

    ...: Ophiothrix orstedii, Ophiothrix angulata, Ophiocoma wendtii, and Ophiactis savignyi. These water-borne animals were similar in size to the smallest benthic conspecifics found on the reef, but considerably larger than newly metamorphosed postlarvae...

  14. Reproductive biology of Echinometra lucunter (Echinodermata: Echinoidea in a northeast Brazilian sandstone reef

    Directory of Open Access Journals (Sweden)

    Eduardo J.B. Lima

    2009-03-01

    Full Text Available The edible sea urchin Echinometra lucunter (Linnaeus, 1758 is a very common species on the sublittoral-midlittoral in Brazilian rocky shores. The aim of this work was to describe the gametogenesis and reproductive strategy of the E. lucunter population at Muro Alto beach in the Northeast coast of Brazil from August 2004 to August 2005. A total of 240 specimens were collected on the sandstone reef flat from a tidepool during spring low tides. The overall sex ratio was1.12:1,withoutsignificanttemporalvariationexceptinOctober2004. Firsts sexual maturity ocurred in individuals from a diameter of 20.8 mm. There was not a significant difference in gonad index between females and males during the sampling period. The female's gonad index variation was associated with a well-defined spawning, corroborated by the histological analysis of the gonads, which demonstrates sex differences of the gamete production. By contrast, the males showed no clear pattern. It is suggested that continuous reproduction with seasonal peaks in the E. lucunter population occurs at Muro Alto beach.O ouriço-do-mar comestível Echinometra lucunter (Linnaeus, 1758 é uma espécie muito comum no infralitoral e mediolitoral do Brasil. O objetivo deste trabalho foi descrever a gametogênese e a estratégia reprodutiva da população de E. lucunterna praia de Muro Alto entre agosto de 2004 e agosto de 2005. Um total de 240 espécimes foi capturado de uma poça de maré situada no topo recifal, durante as marés baixas de sizígia. A razão sexual total foi de 1,12:1 sem variação temporal significativa, exceto em outubro de 2004. A primeira maturidade sexual ocorreu em indivíduos a partir de 20,8 mm de diâmetro. Não houve nenhuma diferença significativa no índice gonadal entre fêmeas e machos durante o período de amostragem. A variação do índice gonadal das fêmeas foi associada a um período de desova bem definido, corroborado pela análise histológica das gônadas, que demonstra diferenças sexuais na produção de gametas. Ao contrário, os machos não apresentaram nenhum padrão. Sugere-se que a reprodução da população de E. lucunter na praia de Muro Alto é contínua, compicos sazonais.

  15. Embryonic, Larval, and Early Juvenile Development of the Tropical Sea Urchin, Salmacis sphaeroides (Echinodermata: Echinoidea

    Directory of Open Access Journals (Sweden)

    M. Aminur Rahman

    2012-01-01

    Full Text Available Salmacis sphaeroides (Linnaeus, 1758 is one of the regular echinoids, occuring in the warm Indo-West Pacific, including Johor Straits, between Malaysia and Singapore. In order to investigate the developmental basis of morphological changes in embryos and larvae, we documented the ontogeny of S. sphaeroides in laboratory condition. Gametes were obtained from adult individuals by 0.5 M KCl injection into the coelomic cavity. Fertilization rate at limited sperm concentration (10−5 dilution was 96.6±1.4% and the resulting embryos were reared at 24°C. First cleavage (2-cell, 4-cell, 8-cell, 16-cell, 32-cell, and multicell (Morulla stages were achieved 01.12, 02.03, 02.28, 02.51, 03.12, and 03.32 h postfertilization. Ciliated blastulae with a mean length of 174.72±4.43 μm hatched 08.45 h after sperm entry. The gastrulae formed 16.15 h postfertilization and the archenteron elongated constantly while ectodermal red-pigmented cells migrated synchronously to the apical plate. Pluteus larva started to feed unicellular algae in 2 d, grew continuously, and finally attained metamorphic competence in 35 d after fertilization. Metamorphosis took approximately 1 h 30 min from attachment to the complete resorption of larval tissues and the development of complete juvenile structure with adult spines, extended tubefeet and well-developed pedicellaria, the whole event of which usually took place within 1 d postsettlement. This study represents the first successful investigation on embryonic, larval, and early juvenile development of S. sphaeroides. The findings would greatly be helpful towards the understanding of ontogeny and life-history strategies, which will facilitate us to develop the breeding, seed production, and culture techniques of sea urchins in captive condition.

  16. Abundance, distribution and size structure of Diadema antillarum (Echinodermata: Diadematidae in South Eastern Cuban coral reefs

    Directory of Open Access Journals (Sweden)

    F Martín Blanco

    2010-06-01

    Full Text Available The 1983-1984 mass mortality event of Diadema antillarum affected more than 93% of the total Caribbean population. Although there are no records about the status of Diadema populations before and after die-off on Cuban reefs, anecdotal information suggests that populations were struck. We analyzed spatial variation in the abundance and size structure of D. antillarum in 22 reefs sites in Jardines de la Reina, from June 2004 to September 2005. Counts of Diadema were performed in five 30x2m transects at each sampling site and sampling time, and test diameters were measured in September 2005 at the same fore reefs. Abundances were higher at reef crests (mean densities 0.08-2.18 ind./m², while reef slope populations reached a maximum site level of 0.13 ind./m² at only one site and showed values up to three orders of magnitude lower than those from reef crests. Highest abundance occurred at the west margin of major channels between keys where larval recruitment seems to be favored by local oceanographic features and facilitated by the abundance of Echinometra lucunter. The size frequency distribution of D. antillarum indicates that recruitment began to be noticeable three years before September 2005, suggesting these populations were depleted in the past and they are recovering now. Rev. Biol. Trop. 58 (2: 663-676. Epub 2010 June 02.La mortalidad de Diadema antillarum en 1983-1984 afectó más del 93% de la población del Caribe. Aunque no existen datos publicados sobre el estado de sus poblaciones en arrecifes cubanos antes y después de la mortalidad, se conoce anecdóticamente que fueron afectadas. En el presente trabajo se analizan las variaciones espaciales de la abundancia y estructura de tallas de D. antillarum en 22 arrecifes frontales en Jardines de la Reina, para lo cual se realizaron cinco recorridos de 30x2m en cada sitio entre Junio de 2004 y Septiembre de 2005. Las densidades de Diadema fueron mayores en las crestas arrecifales (0.08-2.18 ind./m² mientras que en las pendientes fueron hasta tres órdenes de magnitud menor y la densidad máxima fue 0.13 ind./m². Las crestas con mayor abundancia de Diadema están ubicadas en los márgenes de las grandes pasas existentes entre cayos donde el reclutamiento parece estar favorecido por las condiciones oceanográficas locales y facilitado por la abundancia de Echinometra lucunter. La distribución de frecuencia de tallas de Diadema sugiere que el reclutamiento comenzó a ser notable aproximadamente tres años antes del muestreo, indicando que en el pasado sus poblaciones estuvieron afectadas y ahora están recuperándose.

  17. Histamine is a modulator of metamorphic competence in Strongylocentrotus purpuratus (Echinodermata: Echinoidea

    Directory of Open Access Journals (Sweden)

    Sutherby Josh

    2012-04-01

    Full Text Available Abstract Background A metamorphic life-history is present in the majority of animal phyla. This developmental mode is particularly prominent among marine invertebrates with a bentho-planktonic life cycle, where a pelagic larval form transforms into a benthic adult. Metamorphic competence (the stage at which a larva is capable to undergo the metamorphic transformation and settlement is an important adaptation both ecologically and physiologically. The competence period maintains the larval state until suitable settlement sites are encountered, at which point the larvae settle in response to settlement cues. The mechanistic basis for metamorphosis (the morphogenetic transition from a larva to a juvenile including settlement, i.e. the molecular and cellular processes underlying metamorphosis in marine invertebrate species, is poorly understood. Histamine (HA, a neurotransmitter used for various physiological and developmental functions among animals, has a critical role in sea urchin fertilization and in the induction of metamorphosis. Here we test the premise that HA functions as a developmental modulator of metamorphic competence in the sea urchin Strongylocentrotus purpuratus. Results Our results provide strong evidence that HA leads to the acquisition of metamorphic competence in S. purpuratus larvae. Pharmacological analysis of several HA receptor antagonists and an inhibitor of HA synthesis indicates a function of HA in metamorphic competence as well as programmed cell death (PCD during arm retraction. Furthermore we identified an extensive network of histaminergic neurons in pre-metamorphic and metamorphically competent larvae. Analysis of this network throughout larval development indicates that the maturation of specific neuronal clusters correlates with the acquisition of metamorphic competence. Moreover, histamine receptor antagonist treatment leads to the induction of caspase mediated apoptosis in competent larvae. Conclusions We conclude that HA is a modulator of metamorphic competence in S. purpuratus development and hypothesize that HA may have played an important role in the evolution of settlement strategies in echinoids. Our findings provide novel insights into the evolution of HA signalling and its function in one of the most important and widespread life history transitions in the animal kingdom - metamorphosis.

  18. Population Biology of Tripneustes gratilla (Linnaeus (Echinodermata in Seagrass Beds of Southern Guimaras, Philippines

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    Joshua Militar Regalado

    2010-12-01

    Full Text Available The sea urchin Tripneustes gratilla is a major grazer found in seagrass beds of southern Guimaras, Philippines. Monthly length-frequency data from January 2008 to June 2009 were used to estimate the growth, recruitment pattern and mortality rate with the use of FiSAT II. The estimated values for the Von Bertalanffy growth parameters L(n/k(asymptotic length and K (growth coefficient were 114.2 mm and 1.08 respectively. Monthly densities ranged from 0.06 to 0.58 per m² with a mean value of 0.26 per m². Monthly biomass ranged from 4.1 to 49.5 grams per m² with a mean value of 21.15 grams per m². T. gratilla density and biomass were observed to be highest during the month of November 2008. The recruitment pattern showed a major broad peak and a minor peak separated by four months. Total mortality (Z from the length-converted catch curve was computed to be 4.74 per year.

  19. Ophiomusium acuferum (Ophiolepididae and Ophiomisidium pulchellum (Ophiuridae (Ophiuroidea: Echinodermata, redescription based on the Brazilian specimens

    Directory of Open Access Journals (Sweden)

    Michela Borges

    2011-04-01

    Full Text Available Ophiomusium (Ophiolepididae and Ophiomisidium (Ophiuridae are similar, but differ in features such as size of the adult, number of disc dorsal plates, length of the arms, shape of the first ventral arm plates and number of the tentacle. In this contribution, a large number of specimens of Ophiomusium acuferum Lyman, 1869 and Ophiomisidium pulchellum (Wyville Thomson, 1878 were sampled from southeastern and southern Brazilian at depths ranging from 46 to 1300 m. A close analysis has shown that specimens identified as Ophiomisidium pulchellum (C.W. Thomson, 1877 in several Brazilian museums are actually Ophiomusium acuferum Lyman, 1875. A total of 2330 individuals were examined: 2046 specimens of Ophiomusium acuferum ('Evaluation of the sustainable potential of living resources from the Brazilian Economic Exclusive Zone/Score South - Benthos' - REVIZEE; 'Rational usage of coastal ecosystems from the Brazilian Tropical Region: São Paulo State - Integrated Project/Subproject Benthos' - INTEGRADO; and the MD55/Brazil and 284 of Ophiomisidium pulchellum (MD55/Brazil. The disc diameter of each individual was measured and the specimens were digitally photographed. The samples studied are deposited in the Museum of Zoology of the University of Campinas and Institute of Biology at the Federal University of Rio de Janeiro. The specimens from the MD55 are deposited at the Paris Museum National d'Histoire Naturelle. An identification key to these species is provided here. A detailed morphological analysis and redescription of both species, comparisons, and their geographic distribution in Brazil are discussed.

  20. Identification of echinoderms (Echinodermata) from an anchialine cave in Cozumel Island, Mexico, using DNA barcodes.

    Science.gov (United States)

    Bribiesca-Contreras, Guadalupe; Solís-Marín, Francisco A; Laguarda-Figueras, Alfredo; Zaldívar-Riverón, Alejandro

    2013-11-01

    The echinoderm species richness of the Aerolito de Paraiso anchialine cave, on Cozumel Island, in the Mexican Caribbean, is assessed on the basis of morphological and DNA barcoding data. We included specimens from this cave system and from different open sea areas, and employed two different approaches for species delineation based on DNA barcoding data: a 2% cox1 divergence and the general mixed Yule-coalescent (GMYC) approaches. We subsequently compared the results derived from these approaches with our morphospecies discrimination. A total of 188 cox1 sequences belonging to specimens of four echinoderm classes were examined. The 2% cox1 divergence and GMYC approaches recovered 78 and 70 putative species, respectively, 24 and 22 of which corresponded to specimens from the anchialine system. Of 26 echinoderm species identified in the cave system, seven appear to be endemic to it. Among these are Copidaster carvenicola Solís-Marín & Laguarda-Figueras, 2010, two morphologically distinctive, undescribed species belonging to Asterinides and Ophionereis and four probably cryptic undescribed species originally assigned to Amphipholis squamata (Delle Chiaje, 1839), Astropecten duplicatus Gray, 1840, Copidaster lymani (AH Clark, 1948) and Ophiothrix angulata (Say, 1825). Further research and protection of this particularly fragile ecosystem becomes urgent because construction of tourism developments is planned nearby. © 2013 John Wiley & Sons Ltd.

  1. Henricia djakonovi sp. nov. (Echinodermata, Echinasteridae: a new sea star species from the Sea of Japan

    Directory of Open Access Journals (Sweden)

    Anton Chichvarkhin

    2017-01-01

    Full Text Available A new sea star species, H. djakonovi sp.n., was discovered in Rudnaya Bay in the Sea of Japan. This is a sympatric species of the well-known and common species Henricia pseudoleviuscula Djakonov, 1958. Both species are similar in body size and proportions, shape of skeletal plates, and life coloration, which distinguishes them from the other Henricia species inhabiting the Sea of Japan. Nevertheless, these species can be distinguished by their abactinal spines: in both species, they are short and barrel-like, but the new species is the only Henricia species in Russian waters of the Pacific that possesses such spines with a massive, smooth, bullet-like tip. The spines in H. pseudoleviuscula are crowned with a variable number of well-developed thorns. About half (<50% of the abactinal pseudopaxillae in the new species are oval, not crescent-shaped as in H. pseudoleviuscula.

  2. New records of Ophiuroidea (Echinodermata) from shallow waters off Maceió, State of Alagoas, Brazil

    OpenAIRE

    Manso, Cynthia Lara de Castro; Lima, Maria Lilian F.; Correia, Monica D.; Sovierzoski, Hilda H.

    2011-01-01

    Aspects of the distribution and ecology of ophiuroids from shallow waters off Maceió, State of Alagoas in north-eastern Brazil were characterized. The ophiuroid fauna comprised 16 species in nine genera and seven families, including three endemic species from Brazil, Ophiocnida loveni, Ophiactis brasiliensis and Amphiura kinbergi, and also four new records for the coastal reef system off north-eastern Brazil. On coral reefs 15 species were found and Ophiothrix angulata was the most abundant s...

  3. Inhibition of arm regeneration by Ophioderma brevispina (Echinodermata, Ophiuroidea) by tributyltin oxide and triphenyltin oxide

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, G.E.; McLaughlin, L.L.; Louie, M.K.; Deans, C.H.; Lores, E.M.

    1986-08-01

    Effects of water-bourne toxicants on regeneration of arms by the brittle star, Ophioderma brevispina, are described. Regeneration was inhibited by 0.1 micrograms liter-1 bis(tri-n-butyltin)oxide and bis(triphenyltin)oxide. Both substances are known to act upon the nervous system, and it is suggested that inhibition was caused by neurotoxicological action of the tin compounds or by their direct effect upon tissue at the breakage point. The former is most likely because regeneration is mediated by the radial nerves of brittle stars.

  4. Ophioderma peruana, a new species of brittlestar (Echinodermata, Ophiuroidea, Ophiodermatidae) from the Peruvian coast

    National Research Council Canada - National Science Library

    Pineda-Enríquez, Tania; Solís-Marín, Francisco A; Hooker, Yuri; Alfredo Laguarda-Figueras

    2013-01-01

    Ophioderma peruana sp. n. is a new species of Ophiodermatidae, extending the distribution of the genus Ophioderma to Lobos de Afuera Island, Peru, easily distinguishable from its congeners by its peculiarly fragmented dorsal arm plates...

  5. First records of echinoderms (Echinodermata) in shallow waters of Corn Island, Caribe, Nicaragua

    OpenAIRE

    Quinn-Lampson, Shaungnessy Roshelle; Benito-Sandino, Osmar; Solís-Marín, Francisco Alonso; Arriaga-Ochoa, Julio; Laguarda-Figueras, Alfredo

    2016-01-01

    There are few works on ecology and diversity of echinoderms in Nicaragua. Studies of many faunal groups of marine invertebrates, in particular which should focus on the fauna of tropical areas, have been scarce or have received only limited attention from the scientific community and government authorities of the South Atlantic Autonomous Region (RAAS) of Nicaragua. Scientific research on these groups has targeted mainly resources of commercial importance (e.g. spiny lobster, Panulirus argus)...

  6. Ophioderma peruana, a new species of brittlestar (Echinodermata, Ophiuroidea, Ophiodermatidae from the Peruvian coast

    Directory of Open Access Journals (Sweden)

    Tania Pineda-Enríquez

    2013-12-01

    Full Text Available Ophioderma peruana sp. n. is a new species of Ophiodermatidae, extending the distribution of the genus Ophioderma to Lobos de Afuera Island, Peru, easily distinguishable from its congeners by its peculiarly fragmented dorsal arm plates. Dense granules, rounded or polygonal cover the disc, the radial shields may be naked or completely covered by granules. A good character for recognizing this species in the field is the dorsal side of the disc which is brown with disc granules lighter cream and brown, the arms are mottled with whitish spots and the ventral part of the disc on the interradial part is brown and the radial part bright yellow.

  7. Gametogenic cycle of Ophioderma januarii, a common Ophiodermatidae (Echinodermata: Ophiuroidea) in southeastern Brazil

    OpenAIRE

    Michela Borges; Leonardo Q. Yokoyama; Antonia C. Z. Amaral

    2009-01-01

    This study describes the gametogenic cycle of Ophioderma januarii Lütken, 1856, a common species of ophiuroid in Southeastern Brazil. The specimens were collected during the project "Biodiversidade Bêntica Marinha no Estado de São Paulo-BIOTA/FAPESP-Bentos Marinho" (Marine benthic biodiversity in the State of São Paulo-BIOTA/ Fapesp-Marine Benthos) which was conducted off the northern coast of the state of São Paulo. Specimens were captured monthly between February 2001 and December 2002. Due...

  8. Ophioderma peruana, a new species of brittlestar (Echinodermata, Ophiuroidea, Ophiodermatidae) from the Peruvian coast.

    Science.gov (United States)

    Pineda-Enríquez, Tania; Solís-Marín, Francisco A; Hooker, Yuri; Alfredo Laguarda-Figueras

    2013-01-01

    Ophioderma peruana sp. n. is a new species of Ophiodermatidae, extending the distribution of the genus Ophioderma to Lobos de Afuera Island, Peru, easily distinguishable from its congeners by its peculiarly fragmented dorsal arm plates. Dense granules, rounded or polygonal cover the disc, the radial shields may be naked or completely covered by granules. A good character for recognizing this species in the field is the dorsal side of the disc which is brown with disc granules lighter cream and brown, the arms are mottled with whitish spots and the ventral part of the disc on the interradial part is brown and the radial part bright yellow.

  9. Inhibition of arm regeneration by Ophioderma brevispina (Echinodermata, Ophiuroidea) by tributyltin oxide and triphenyltin oxide.

    Science.gov (United States)

    Walsh, G E; McLaughlin, L L; Louie, M K; Deans, C H; Lores, E M

    1986-08-01

    Effects of water-bourne toxicants on regeneration of arms by the brittle star, Ophioderma brevispina, are described. Regeneration was inhibited by 0.1 micrograms liter-1 bis(tri-n-butyltin)oxide and bis(triphenyltin)oxide. Both substances are known to act upon the nervous system, and it is suggested that inhibition was caused by neurotoxicological action of the tin compounds or by their direct effect upon tissue at the breakage point. The former is most likely because regeneration is mediated by the radial nerves of brittle stars.

  10. Ophioderma peruana, a new species of brittlestar (Echinodermata, Ophiuroidea, Ophiodermatidae) from?the Peruvian coast

    OpenAIRE

    Tania Pineda-Enríquez; Francisco Solís-Marín; Yuri Hooker; Alfredo Laguarda-Figueras

    2013-01-01

    Abstract Ophioderma peruana sp. n. is a new species of Ophiodermatidae, extending the distribution of the genus Ophioderma to Lobos de Afuera Island, Peru, easily distinguishable from its congeners by its peculiarly fragmented dorsal arm plates. Dense granules, rounded or polygonal cover the disc, the radial shields may be naked or completely covered by granules. A good character for recognizing this species in the field is the dorsal side of the disc which is brown with disc granules lighter...

  11. Abundance, distribution and size structure of Diadema antillarum (Echinodermata: Diadematidae in South Eastern Cuban coral reefs

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    F Martín Blanco

    2010-06-01

    Full Text Available The 1983-1984 mass mortality event of Diadema antillarum affected more than 93% of the total Caribbean population. Although there are no records about the status of Diadema populations before and after die-off on Cuban reefs, anecdotal information suggests that populations were struck. We analyzed spatial variation in the abundance and size structure of D. antillarum in 22 reefs sites in Jardines de la Reina, from June 2004 to September 2005. Counts of Diadema were performed in five 30x2m transects at each sampling site and sampling time, and test diameters were measured in September 2005 at the same fore reefs. Abundances were higher at reef crests (mean densities 0.08-2.18 ind./m², while reef slope populations reached a maximum site level of 0.13 ind./m² at only one site and showed values up to three orders of magnitude lower than those from reef crests. Highest abundance occurred at the west margin of major channels between keys where larval recruitment seems to be favored by local oceanographic features and facilitated by the abundance of Echinometra lucunter. The size frequency distribution of D. antillarum indicates that recruitment began to be noticeable three years before September 2005, suggesting these populations were depleted in the past and they are recovering now. Rev. Biol. Trop. 58 (2: 663-676. Epub 2010 June 02.

  12. Marine Flora and Fauna of the Northeastern United States. Echinodermata: Holothuroidea.

    Science.gov (United States)

    Pawson, David L.

    This report is part of a subseries entitled "Marine Flora and Fauna of the Northeastern United States" which is designed for use by biology students, biologists, biological oceanographers and informed laymen. Contents of this report include: (1) Introduction; (2) Morphology; (3) Systematic Characters; (4) Examination Procedures; (5)…

  13. Histamine is a modulator of metamorphic competence in Strongylocentrotus purpuratus (Echinodermata: Echinoidea)

    OpenAIRE

    Sutherby Josh; Giardini Jamie-Lee; Nguyen Julia; Wessel Gary; Leguia Mariana; Heyland Andreas

    2012-01-01

    Abstract Background A metamorphic life-history is present in the majority of animal phyla. This developmental mode is particularly prominent among marine invertebrates with a bentho-planktonic life cycle, where a pelagic larval form transforms into a benthic adult. Metamorphic competence (the stage at which a larva is capable to undergo the metamorphic transformation and settlement) is an important adaptation both ecologically and physiologically. The competence period maintains the larval st...

  14. Histamine is a modulator of metamorphic competence in Strongylocentrotus purpuratus (Echinodermata: Echinoidea).

    Science.gov (United States)

    Sutherby, Josh; Giardini, Jamie-Lee; Nguyen, Julia; Wessel, Gary; Leguia, Mariana; Heyland, Andreas

    2012-04-27

    A metamorphic life-history is present in the majority of animal phyla. This developmental mode is particularly prominent among marine invertebrates with a bentho-planktonic life cycle, where a pelagic larval form transforms into a benthic adult. Metamorphic competence (the stage at which a larva is capable to undergo the metamorphic transformation and settlement) is an important adaptation both ecologically and physiologically. The competence period maintains the larval state until suitable settlement sites are encountered, at which point the larvae settle in response to settlement cues. The mechanistic basis for metamorphosis (the morphogenetic transition from a larva to a juvenile including settlement), i.e. the molecular and cellular processes underlying metamorphosis in marine invertebrate species, is poorly understood. Histamine (HA), a neurotransmitter used for various physiological and developmental functions among animals, has a critical role in sea urchin fertilization and in the induction of metamorphosis. Here we test the premise that HA functions as a developmental modulator of metamorphic competence in the sea urchin Strongylocentrotus purpuratus. Our results provide strong evidence that HA leads to the acquisition of metamorphic competence in S. purpuratus larvae. Pharmacological analysis of several HA receptor antagonists and an inhibitor of HA synthesis indicates a function of HA in metamorphic competence as well as programmed cell death (PCD) during arm retraction. Furthermore we identified an extensive network of histaminergic neurons in pre-metamorphic and metamorphically competent larvae. Analysis of this network throughout larval development indicates that the maturation of specific neuronal clusters correlates with the acquisition of metamorphic competence. Moreover, histamine receptor antagonist treatment leads to the induction of caspase mediated apoptosis in competent larvae. We conclude that HA is a modulator of metamorphic competence in S. purpuratus development and hypothesize that HA may have played an important role in the evolution of settlement strategies in echinoids. Our findings provide novel insights into the evolution of HA signalling and its function in one of the most important and widespread life history transitions in the animal kingdom--metamorphosis.

  15. HYBRIDIZATION OF SYMPATRIC PATIRIELLA SPECIES (ECHINODERMATA: ASTEROIDEA) IN NEW SOUTH WALES.

    Science.gov (United States)

    Byrne, Maria; Anderson, Marti Jane

    1994-06-01

    Three species of the asteroid genus Patiriella occur sympatrically in New South Wales and the possibility for hybridization among them was examined through a series of cross-fertilization experiments. Patiriella calcar and P. gunnii are morphologically distinct as adults but indistinguishable as larvae. Patiriella exigua is morphologically distinct in both its adult and larval morphologies. The gametes of P. calcar and P. gunnii were reciprocally compatible: laboratory crosses between these species produced viable hybrid juveniles. In crosses between female P. calcar and male P. gunnii, most of the juveniles metamorphosed with an arm number intermediate between that of the parents, whereas crosses between female P. gunnii and male P. calcar produced juveniles with an arm number more similar to the maternal phenotype. Heterospecific crosses with P. exigua resulted in low fertilization rates, and viable hybrids were not produced. This species appears capable of self-fertilization. Because hybrids between P. calcar and P. gunnii were viable, neither gametic incompatibility nor hybrid inviability appears to ensure reproductive isolation between these species. Ecological or habitat segregation and temporal separation in breeding may isolate these species in the field. The results demonstrate that if gamete surface recognition molecules are involved in fertilization of P. calcar and P. gunnii, then they are not strongly species specific, at least at the sperm concentrations used in this study. Reproductive isolation between these species has evolved despite their gametic compatibility. In contrast, P. exigua is isolated from its congeners because of gametic incompatibility and several features characteristic of its reproduction and development. The implications of these findings for reproductive isolation and speciation of Patiriella and for the evolution of reproductive isolation in free-spawning marine organisms are discussed. © 1994 The Society for the Study of Evolution.

  16. Holistic morphometric analysis of growth of the sand dollar Echinarachnius parma (Echinodermata:Echinoidea:Clypeasteroida).

    Science.gov (United States)

    Zachos, Louis G

    2015-12-02

    Holistic morphometrics is a term implying complete shape characterization of all of the structural parts of an organism. The skeleton of an echinoid is comprised of hundreds of individual plates arranged in a closed 3-dimensional mosaic forming the test. GIS software and techniques were used to generate topologically correct digital models of an ontogenetic series of specimens of the sand dollar echinoid Echinarachnius parma. Plate growth can be considered in proportion to overall skeleton growth, resulting in a linear model of relative growth. Alternatively, separate logistic equations can be fit to the ontogenetic series of homologous plate areas using nonlinear least squares regression to result in a model for instantaneous growth. The linear and logistic parameters of the models describe the allometric growth of plates from different viewpoints. Growth is shown to fall into characteristic patterns defining distinct plate growth domains associated with development of the imago (larval) skeleton just prior to metamorphosis, early growth associated with expansion of the corona and fold-over (forming the flattened body form), juvenile growth and formation of petals, and adult growth. Functions of growth, plate translocation, plate juxtaposition between aboral and oral surfaces, and relationships with internal buttressing are quantified. Results offer explanations for general skeletal symmetry, distinction between ambulacral and interambulacral growth, the relationship of growth to internal buttressing, existence of a distinct petalodium, and anterior-posterior asymmetry during development. The parametric values of growth functions derived from the results are a basis for computational modeling of growth and development in sand dollars.

  17. Fossil echinoid (Echinoidea, Echinodermata) diversity of the Early Cretaceous (Hauterivian) in the Paris Basin (France)

    OpenAIRE

    Sophie Benetti; Thomas Saucède; Bruno David

    2013-01-01

    Abstract This dataset inventories occurrence records of fossil echinoid specimens collected in the Calcaires ? Spatangues Formation (CSF) that crops out in the southeast of the Paris Basin (France), and is dated from the Acanthodiscus radiatus chronozone (ca. 132 Ma, early Hauterivian, Early Cretaceous). Fossil richness and abundance of the CSF has attracted the attention of palaeontologists since the middle of the nineteenth century. This dataset compiles occurrence data (referenced by local...

  18. An occurence records database of Irregular Echinoids (Echinodermata: Echinoidea) in Mexico

    OpenAIRE

    Martínez-Melo, Alejandra; Solís-Marín, Francisco; Buitrón-Sánchez, Blanca; Laguarda-Figueras, Alfredo

    2016-01-01

    Abstract Background Research on echinoderms in Mexico began in the late nineteenth century. We present a dataset that includes the taxonomic and geographic information of irregular echinoids from Mexico, housed in four collections: 1) Colecci?n Nacional de Equinodermos ?Ma. Elena Caso Mu?oz? from the Instituto de Ciencias del Mar y Limnolog?a (ICML), Universidad Nacional Aut?noma de M?xico (UNAM); 2) Invertebrate Zoology Collection, Smithsonian Museum of Natural History, Washington, D.C., Uni...

  19. Taxonomic guide and historical review of starfishes in northeastern Brazil (Echinodermata, Asteroidea)

    Science.gov (United States)

    Gondim, Anne Isabelley; Christoffersen, Martin Lindsey; Pereira Dias, Thelma Lúcia

    2014-01-01

    Abstract Presently more than 1900 species of sea stars are recognized, of which 77 are recorded for the coast of Brazil. Although the first starfish record in Brazil was published 363 years ago, our knowledge of this fauna remains unsatisfactory from a systematic and ecological point of view, particularly in the north and northeastern regions of the country. This study provides the first annotated list of sea stars from northeastern Brazil. Material described herein is housed at the collections of the Federal University of Paraíba, Federal University of Sergipe, and the Federal University of Bahia, Museum of Zoology of the University of São Paulo and Museu Nacional do Rio de Janeiro. Twenty-one species were identified, belonging to 12 genera, 10 families, and 5 orders. Descriptions of species are provided. Three new occurrences were recorded for northeast Brazil: Astropecten alligator, Luidia ludwigi scotti, and Mithrodia clavigera. Highest diversities of Asteroidea were encountered for the states of Bahia (n = 14 spp), Paraíba (n = 12 spp) and Pernambuco (n = 9 spp). No species were recorded for the states of Maranhão and Sergipe. Sandy substrates and depths below 10 m were the least sampled areas over the continental shelf. Herein we provide a first panorama on the fauna of Asteroidea occurring in the northeast region of Brazil, hopefully to function as a basic reference for biodiversity studies in this poorly studied area. PMID:25408612

  20. [Abundance of Diadema antillarum (Echinodermata: Echinoidea) in the coasts of Venezuela].

    Science.gov (United States)

    Noriega, Nicida; Pauls, Sheila M; del Mónaco, Carlos

    2006-09-01

    Diadema antillarum is a shallow-water sea-urchin from the tropical Atlantic whose populations almost disappeared in 1983-84 because of widespread mortalities which reached 87-100 %. In Venezuela, urchin population densities before the mortality event were comparable to those of other Caribbean regions; however, later abundancies remain unknown. The objectives of this study were to evaluate the recent densities of certain D. antillarum populations along the Venezuelan coasts and compare the densities at the Parque Nacional Mochima before and after the mortality. At each location urchin densities were determined by means of transects using 1 m2-quadrats as sampling units. The highest mean densities were observed at the sites on the central coast: Ensenada de Oricao, 0.28 ind/m2 (2002) and 1.05 ind/m2 (2003), and Chichiriviche de la Costa, 0.84 ind/m2 (2002) and 0.74 ind/m2 (2003). In Mochima, the mean density before the mortality for D. antillarum oscillated between 0.28 and 4 ind/m2, after the mortality event the mean density varied between 0.15 ind/m2 (2000) and 0.47 ind/m2 (2000). The populations of D. antillarum studied at Parque Nacional Morrocoy and Refugio de Fauna Silvestre Cuare showed highest densities at Playuela (0.43 ind/m2) and Cayo Sur (0.95 ind/m2) respectively, whereas other sites showed densities below 0.1 ind/m2. The density registered at Playuela in 2003 is lower than that reported before the mortality event (0.58-3.64 ind/m2). The density for Parque Nacional Archipiélago de Los Roques, specifically for the Arrecife de Herradura remained constant between 2002 and 2003 with values between 0.22-0.23 ind/m2 respectively. To conclude, the sea urchin abundancies observed at most of the Venezuelan coastal sites that we studied were higher than those reported for other areas of the northern Caribbean, even though the values have not yet returned to those preceding the 1984 mass-mortality event, due to the slow recovery of the populations.

  1. The oldest post-Palaeozoic Crinoid and Permian-Triassic origins of the Articulata (Echinodermata).

    Science.gov (United States)

    Oji, Tatsuo; Twitchett, Richard J

    2015-04-01

    The Crinoidea are the most primitive class of living echinoderms, and suffered a severe crisis during the Late Permian mass extinction event. All post-Palaeozoic crinoids, including living species, belong to the Articulata, and morphological and recent molecular studies demonstrate that they form a monophyletic clade. The Articulata originated from Palaeozoic cladid crinoids, but the nature and timing of their origination remains obscure. Problems with understanding the origin and early evolution of the Articulata have arisen because the Permian-Triassic crinoid fossil record is particularly poor. We report on a new genus and species from the earliest Triassic, which is the oldest known post-Palaeozoic articulate crinoid and fundamentally alters our understanding of the early evolution of the Articulata. Prior to this study, the most primitive post-Palaeozoic articulate was thought to be Holocrinus of the order Isocrinida. Unexpectedly, the new taxon belongs to the order Encrinida, which reveals a previously hidden diversity of crinoids in the earliest Triassic. Its discovery implies either a dramatic radiation of crinoids in the immediate post-extinction aftermath, when environmental conditions were at their most severe, or a pre-extinction origin of the crown group articulates and survival of multiple lineages.

  2. Influence of sediment-organic matter quality on growth and polychlorobiphenyl bioavailability in Echinodermata (Amphiura filiformis)

    Energy Technology Data Exchange (ETDEWEB)

    Gunnarsson, J.S.; Granberg, M.E.; Nilsson, H.C.; Rosenberg, R.; Hellman, B.

    1999-07-01

    Sediment total organic carbon (TOC) content is considered to be a primary food source for benthic invertebrates and a major factor influencing the partitioning and bioavailability of sediment-associated organic contaminants. Most studies report that both toxicity and uptake of sediment-associated contaminants by benthic organisms are inversely proportional to sediment TOC content. The aim of this study was to determine the importance of the TOC quality for the bioavailability of sediment-associated organic contaminants and the growth of benthic macrofauna. The common infaunal brittle star Amphiura filiformis was exposed to a base sediment covered by a {sup 14}C-polychlorobipenyl (3,3{prime}4,4{prime}-{sup 14}C-tetrachlorobiphenyl (TCB)) contaminated top layer (0--2 cm), enriched to the same TOC content with 31 g TOC/m{sup 2} of different quality and origin. The following carbon sources, ranging from labile to refractory, were used: (1) green macroalga (Ulva lactuca), (2) brown macroalga (Ascophyllum nodosum), (3) eelgrass (Zostera Marina), (4) phytoplankton (Ceratium spp.), and (5) lignins of terrestrial origin. Characterization of the organic matter quality was accomplished by measuring the content of amino acids, lipids, C, N, and polyphenolic compounds. The reactivity of the sedimentary organic matter was assessed by means of respiration and dissolved inorganic nitrogen flux measurements. The experiment was carried out in 1-L glass jars, each containing four brittle stars and the contaminated and enriched sediment. The jars were circulated in a flow-through mode with filtered seawater. Somatic growth (regeneration of a precut arm) and bioaccumulation of {sup 14}C-TCB were measured at 10 sampling occasions during 48 d of exposure. Growth rates, TCB uptake rates, and steady-state concentrations differed significantly between treatments and were correlated to the qualities of the organic substrates. The greatest TCB accumulation and growth were observed in treatments with the most labile organic substrates and the lowest accumulation and growth were seen with the most refractory substrates. Results from this experiment suggest that the bioaccumulation of organic contaminants in benthic infauna is dependent on the nutritional quality of the sedimentary organic matter.

  3. Embryonic, larval, and juvenile development of the sea biscuit Clypeaster subdepressus (Echinodermata: Clypeasteroida.

    Directory of Open Access Journals (Sweden)

    Bruno C Vellutini

    Full Text Available Sea biscuits and sand dollars diverged from other irregular echinoids approximately 55 million years ago and rapidly dispersed to oceans worldwide. A series of morphological changes were associated with the occupation of sand beds such as flattening of the body, shortening of primary spines, multiplication of podia, and retention of the lantern of Aristotle into adulthood. To investigate the developmental basis of such morphological changes we documented the ontogeny of Clypeaster subdepressus. We obtained gametes from adult specimens by KCl injection and raised the embryos at 26 degrees C. Ciliated blastulae hatched 7.5 h after sperm entry. During gastrulation the archenteron elongated continuously while ectodermal red-pigmented cells migrated synchronously to the apical plate. Pluteus larvae began to feed in 3 d and were 20 d old at metamorphosis; starved larvae died 17 d after fertilization. Postlarval juveniles had neither mouth nor anus nor plates on the aboral side, except for the remnants of larval spicules, but their bilateral symmetry became evident after the resorption of larval tissues. Ossicles of the lantern were present and organized in 5 groups. Each group had 1 tooth, 2 demipyramids, and 2 epiphyses with a rotula in between. Early appendages consisted of 15 spines, 15 podia (2 types, and 5 sphaeridia. Podial types were distributed in accordance to Lovén's rule and the first podium of each ambulacrum was not encircled by the skeleton. Seven days after metamorphosis juveniles began to feed by rasping sand grains with the lantern. Juveniles survived in laboratory cultures for 9 months and died with wide, a single open sphaeridium per ambulacrum, aboral anus, and no differentiated food grooves or petaloids. Tracking the morphogenesis of early juveniles is a necessary step to elucidate the developmental mechanisms of echinoid growth and important groundwork to clarify homologies between irregular urchins.

  4. Occurrence of abnormal starfish Astropecten indicus (Doderlein, 1888 (Echinodermata: Astroidea along Southeast coast of India

    Directory of Open Access Journals (Sweden)

    K. Prabhu

    2012-11-01

    Full Text Available Starfish Astropecten indicus was collected from bycatch landings at Mudasalodai fishing harbour, Tamil Nadu (India in November 2011. Totally 134 specimens collected among three specimens (2,2% have abnormally developed four and six arms. Normally, A. indicus has five arms and the deviation from pentamerism is a rare phenomenon in starfishes. The present observations suggest that deviations from pentamerism are not a heritable character but are a consequence of environmental perturbations on the metamorphosis of larvae and/or abnormal regeneration of arms.

  5. Taxonomic guide and historical review of starfishes in northeastern Brazil (Echinodermata, Asteroidea

    Directory of Open Access Journals (Sweden)

    Anne Gondim

    2014-10-01

    Full Text Available Presently more than 1900 species of sea stars are recognized, of which 77 are recorded for the coast of Brazil. Although the first starfish record in Brazil was published 363 years ago, our knowledge of this fauna remains unsatisfactory from a systematic and ecological point of view, particularly in the north and northeastern regions of the country. This study provides the first annotated list of sea stars from northeastern Brazil. Material described herein is housed at the collections of the Federal University of Paraíba, Federal University of Sergipe, and the Federal University of Bahia, Museum of Zoology of the University of São Paulo and Museu Nacional do Rio de Janeiro. Twenty-one species were identified, belonging to 12 genera, 10 families, and 5 orders. Descriptions of species are provided. Three new occurrences were recorded for northeast Brazil: Astropecten alligator, Luidia ludwigi scotti, and Mithrodia clavigera. Highest diversities of Asteroidea were encountered for the states of Bahia (n = 14 spp, Paraíba (n = 12 spp and Pernambuco (n = 9 spp. No species were recorded for the states of Maranhão and Sergipe. Sandy substrates and depths below 10 m were the least sampled areas over the continental shelf. Herein we provide a first panorama on the fauna of Asteroidea occurring in the northeast region of Brazil, hopefully to function as a basic reference for biodiversity studies in this poorly studied area.

  6. Occurrence of abnormal starfish Astropecten indicus (Doderlein, 1888 (Echinodermata: Astroidea along Southeast coast of India

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    PRABHU kOLANDHASAMY

    2012-08-01

    Starfish Astropecten indicus was collected from bycatch landings at Mudasalodai fishing harbour, Tamil Nadu (India in November 2011. Totally 134 specimens collected among three specimens (2,2% have abnormally developed four and six arms. Normally, A. indicus has five arms and the deviation from pentamerism is a rare phenomenon in starfishes. The present observations suggest that deviations from pentamerism are not a heritable character but are a consequence of environmental perturbations on the metamorphosis of larvae and/or abnormal regeneration of arms.

  7. Reproductive biology in the starfish Echinaster (Othilia guyanensis (Echinodermata: Asteroidea in southeastern Brazil

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    Fátima L. F. Mariante

    2010-01-01

    Full Text Available Echinaster (Othilia guyanensis Clark, 1987 is an endangered starfish distributed throughout the Caribbean and Atlantic Ocean. Even though it has been extensively harvested, little is known about the biology and ecology of this starfish. Here, we examine reproduction seasonality in E. (O. guyanensis. Individuals were collected monthly for one year, including four complete lunar phases. The gonad index (GI was calculated to determine annual and monthly reproductive peaks. Gametogenesis stages were also determined. Sex ratio was 1:1.33 (M:F. Gonadosomatic index, body weight, central disc width and arm length were similar for both sexes. Gonads were present in all animals with arm length greater than 36.2 mm. Lunar phase was not associated with E. (O. guyanensis reproduction. GI and gametogenesis patterns suggest that starfish have an annual reproductive peak with spawning during autumn months (March to May.

  8. Los equinodermos (Echinodermata del arrecife de Cabo Pulmo, Pacífico de México

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    Carlos E. Cintra Buenrostro

    1998-06-01

    Full Text Available Este trabajo presenta una lista sistemática de los equinodermos del arrecife de Cabo Pulmo, México. Los datos fueron obtenidos de revisiones de literatura y labores de campo llevadas a cabo entre los años de 1986 a 1993. Un total de 38 especies han sido registradas para Cabo Pulmo, pero sólo 25 de ellas fueron observadas directamente en el campo durante nuestras visitas, lo que sugiere que la estructura y composición de la comunidad han cambiado de forma importante desde 1943, fecha de los primeros registros de equinodermos para la localidad.A systematic list of the echinoderms from Cabo Pulmo reef, Pacific coast of México (23.5° N, is presented. Data were obtained from field surveys (1986 to 1993, and complemented with literature searches. A total of 38 species have been reported at Cabo Pulmo, but only 25 of them were actually observed in the reef during our visits. This finding suggests that community structure and composition have changed in important ways since 1943, date of the first reports of echinoderms for the locality.

  9. Gametogenic cycle of Ophioderma januarii, a common Ophiodermatidae (Echinodermata: Ophiuroidea in southeastern Brazil

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    Michela Borges

    2009-03-01

    Full Text Available This study describes the gametogenic cycle of Ophioderma januarii Lütken, 1856, a common species of ophiuroid in Southeastern Brazil. The specimens were collected during the project "Biodiversidade Bêntica Marinha no Estado de São Paulo-BIOTA/FAPESP-Bentos Marinho" (Marine benthic biodiversity in the State of São Paulo-BIOTA/ Fapesp-Marine Benthos which was conducted off the northern coast of the state of São Paulo. Specimens were captured monthly between February 2001 and December 2002. Due to the low number of individuals the monthly data was grouped in seasons (spring to winter. A total of 101 specimens were obtained: 33 in spring, 10 in summer, 23 in autumn, and 35 in winter. The gonads of eighty-eight individuals (45 females, 42 males, and one hermaphrodite were analyzed histologically. The male and female gametogenic cycles were classified into five different gonadal stages, which were analyzed separately. The reproductive pattern could be defined through histological analyses of male and female gonads, together with oocyte diameter frequency. Some general conclusions could also be reached: this is a gonochoric species that reproduces year-round but increases its gonadal activity during summer; based on the size of its mature oocytes, it has lecithotrophic development. Apparently, its recruitment is enhanced in late summer, and smaller individuals are more frequent during autumn and winter.

  10. Potencial bioerosivo de Diadema mexicanum (Echinodermata. Echinoidea) en cuatro arrecifes del Pacifico Mexicano.

    OpenAIRE

    HERRERA ESCALANTE, TANIA

    2011-01-01

    La bioerosión juega un papel importante en el balance de los carbonatos en las comunidades arrecifales debido a que debilitan la estructura coralina haciéndola más susceptible a los daños provocados por factores ambientales. Cuando el coral muere es cubierto por algas, lo cual ocasiona que las poblaciones de erizos aumenten y esto incrementa el daño a los corales. El efecto de la bioerosión en las comunidades arrecifales del Pacífico mexicano ha sido poco estudiado, por lo que el objetivo de ...

  11. Novel Circular Single-Stranded DNA Viruses among an Asteroid, Echinoid and Holothurian (Phylum: Echinodermata).

    Science.gov (United States)

    Jackson, Elliot W; Bistolas, Kalia S I; Button, Jason B; Hewson, Ian

    2016-01-01

    Echinoderms are prone to large population fluctuations that can be mediated by pervasive disease events. For the majority of echinoderm disease events the causative pathogen is unknown. Viruses have only recently been explored as potential pathogens using culture-independent techniques though little information currently exists on echinoderm viruses. In this study, ten circular ssDNA viruses were discovered in tissues among an asteroid (Asterias forbesi), an echinoid (Strongylocentrotus droebachiensis) and a holothurian (Parastichopus californicus) using viral metagenomics. Genome architecture and sequence similarity place these viruses among the rapidly expanding circular rep-encoding single stranded (CRESS) DNA viral group. Multiple genomes from the same tissue were no more similar in sequence identity to each other than when compared to other known CRESS DNA viruses. The results from this study are the first to describe a virus from a holothurian and continue to show the ubiquity of these viruses among aquatic invertebrates.

  12. Leptosalenia botanzi sp. nov. (Echinodermata: Echinoidea del Albiense de la cuenca Vasco-Cantábrica.

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    Enric Forner, Txema Moreno.

    2016-01-01

    Esta es la tercera especie de Leptosalenia registrada en la cuenca Vasco-Cantabrica; las otras dos son L. prestensis (Desor, 1856 y L. barredai Forner, 2014. El listado para toda la península ibérica se completa con L. grasi (Cotteau, 1861. L. botanzi es la segunda especie de este género que se describe, recientemente, en el Albiense de la península ibérica. La otra especie L. barredai descrita en la cuenca del Maestrat ha sido encontrada también en la cuenca Vasco-Cantábrica, confirmando la fácil comunicación entre las dos cuencas.

  13. The northward expansion of Synaptula reciprocans (Echinodermata) in the Mediterranean Sea

    DEFF Research Database (Denmark)

    Ragkousis, Michail; Marmara, Dimitra; Filiz, Halit

    2017-01-01

    Synaptula reciprocans was reported in the Mediterranean Sea for the first time back in 1986. Since then there have been numerous reports, following the species' gradual expansion and establishment in the eastern Mediterranean basin. Here we report, by using citizen science methods, from the proje...... titled "Is it Alien to you? Share it" of iSea, the most recent known expansion sites of S. reciprocans, including its new northern-most frontier. Furthermore, the provided photographic evidence testifies for possible interspecies relationships, for the first time....

  14. Biodiversity and distribution of the southern African sea cucumbers (Echinodermata: Holothuroidea).

    Science.gov (United States)

    Thandar, Ahmed S

    2015-12-17

    The history of the southern African holothuroid fauna south of the tropic of Capricorn, is updated and the biodiversity and distribution of the fauna discussed. All five currently recognized orders are represented, distributed over 24 families, 74 genera and 163 species. As many as 117 species are shelf forms comprising the following faunistic components : 36% Indo-Pacific, 12% West Indian Ocean, 1% Atlantic and 51% endemic. Four faunistic provinces are recognized : tropical Indo-Pacific Province on the east coast, extending to St Lucia in northern KwaZulu-Natal; the Subtropical (Natal) province, from this point to Port St. Johns in the Eastern Cape Province; the Warm Temperate (Agulhas) Province from this point to Cape Point in the Western Cape Province; and the Cold Temperate (Namaqua) from Cape Point to Walvis Bay in Namibia. Vertical distribution of the approximately 90 species collected from more than one locality is also given. The origin of the holothuroid fauna is briefly discussed and reiterated that the Indo-Pacific component moved in from the north mostly by way of the Mozambique-Agulhas Current. The origin of the endemic component is obscure but surmised that it is perhaps also of Indo-Pacific origin with negligible contribution from the Atlantic.

  15. Clonal structure through space and time: High stability in the holothurianStichopus chloronotus(Echinodermata).

    Science.gov (United States)

    Pirog, Agathe; Gélin, Pauline; Bédier, Alexandre; Bianchetti, Grégoire; Georget, Stéphane; Frouin, Patrick; Magalon, Hélène

    2017-09-01

    Sea cucumbers are increasingly exploited for human consumption and for their curative properties, and many wild populations are now depleted or in danger of extinction. While aquaculture is seen as an alternative to fisheries and as a mean to restore wild populations, more knowledge is needed on their reproductive strategies to render this practice efficient, notably for fissiparous holothurians, which are some of the mobile animals able of asexual reproduction by transverse fission. Little information is available on their population genetic diversity and structure. Here, the clonal structure of populations of the fissiparous sea cucumber Stichopus chloronotus has been investigated using nine microsatellite loci and a random sampling, at different spatial (intra-reef and inter-reef) and temporal (inter-season and inter-year) scales. Our findings highlight the importance of asexual reproduction in maintaining these populations, and the prevalence of the "initial seedling recruitment" strategy (ISR), leading to a high stability of clonal composition over seasons and years. It also seemed that clonal propagation was limited to the reef scale (<10 km) while reefs were connected by sexual dispersal. This is the first time that clonal structure in sea cucumbers has been studied at such a fine scale, with a specific sampling strategy. It provides key findings on the genetic diversity and structure of fissiparous sea cucumbers, which will be useful for the management of wild populations and aquaculture.

  16. New deep-sea species of Xenoturbella and the position of Xenacoelomorpha.

    Science.gov (United States)

    Rouse, Greg W; Wilson, Nerida G; Carvajal, Jose I; Vrijenhoek, Robert C

    2016-02-04

    The discovery of four new Xenoturbella species from deep waters of the eastern Pacific Ocean is reported here. The genus and two nominal species were described from the west coast of Sweden, but their taxonomic placement remains unstable. Limited evidence placed Xenoturbella with molluscs, but the tissues can be contaminated with prey. They were then considered deuterostomes. Further taxon sampling and analysis have grouped Xenoturbella with acoelomorphs (=Xenacoelomorpha) as sister to all other Bilateria (=Nephrozoa), or placed Xenacoelomorpha inside Deuterostomia with Ambulacraria (Hemichordata + Echinodermata). Here we describe four new species of Xenoturbella and reassess those hypotheses. A large species (>20 cm long) was found at cold-water hydrocarbon seeps at 2,890 m depth in Monterey Canyon and at 1,722 m in the Gulf of California (Mexico). A second large species (~10 cm long) also occurred at 1,722 m in the Gulf of California. The third large species (~15 cm long) was found at ~3,700 m depth near a newly discovered carbonate-hosted hydrothermal vent in the Gulf of California. Finally, a small species (~2.5 cm long), found near a whale carcass at 631 m depth in Monterey Submarine Canyon (California), resembles the two nominal species from Sweden. Analysis of whole mitochondrial genomes places the three larger species as a sister clade to the smaller Atlantic and Pacific species. Phylogenomic analyses of transcriptomic sequences support placement of Xenacoelomorpha as sister to Nephrozoa or Protostomia.

  17. An update on Phytophthora species in California native plant nurseries and restoration areas

    Science.gov (United States)

    S. Rooney-Latham; C.L. Blomquist; M.C. Soriano; Y.Y. Guo; P. Woods; K.L. Kosta; K. Weber; T.J. Swiecki; E.A. Bernhardt; K. Suslow; S.J. Frankel

    2017-01-01

    In 2012, Phytophthora tentaculata was detected for the first time in North America on the roots and crowns of declining sticky monkey flower plants (Diplacus aurantiacus) in a Monterey County, CA native plant nursery. At the time, P. tentaculata was listed among the top five exotic Phytophthora...

  18. Nuevos registros de ofiuroideos (Echinodermata: Ophiuroidea para localidades de Zihuatanejo (Guerrero y Puerto Escondido (Oaxaca, Pacífico mexicano New records of ophiuroids (Echinodermata: Ophiuroidea from localities at Zihuatanejo (Guerrero and Puerto Escondido (Oaxaca, Mexican Pacific

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    M. Rebeca Granja-Fernández

    2011-12-01

    Full Text Available Se presentan nuevos registros de ofiuroideos para localidades de Zihuatanejo, Guerrero y de Puerto Escondido, Oaxaca en el Pacífico mexicano. Mediante recolectas realizadas en diversos sustratos se obtuvieron 12 especies, de las cuales Ophiocoma alexandri Lyman, 1860 y Ophiothela mirabilis (Verrill, 1867 fueron las más ampliamente distribuidas. Este número de especies, el más alto registrado respecto a trabajos previos, se atribuye a la mayor amplitud espacial del esfuerzo de muestreo y a la mayor diversidad de sustratos explorados. Se dan a conocer nuevos sustratos habitados por O. mirabilis y Ophioderma panamensis Lütken, 1859. Se presenta el primer registro de asociación de un organismo juvenil de O. alexandri con un hidrozoo del orden Leptothecata en el Pacífico oriental. A pesar del incremento en el número de especies reconocidas para las localidades, se sugiere llevar a cabo una prospección más amplia del Pacífico tropical mexicano y un mayor esfuerzo de muestreo en diversos sustratos con el fin de incrementar el conocimiento de la biodiversidad de ofiuros en la zona.New records of ophiuroids from localities at Zihuatanejo, Guerrero and Puerto Escondido, Oaxaca in the Mexican Pacific are presented. Based on specimens collected on diverse substrata, 12 species were identified; Ophiocoma alexandri Lyman, 1860 and Ophiothela mirabilis (Verrill, 1867 being the most widely distributed. The larger number of recorded species compared to previous studies may result from a spatially broader sampling and a more thorough survey involving a larger variety of substrata. New substrata for O. mirabilis and Ophioderma panamensis Lütken, 1859 are reported. We document, for first time, the relationship between a juvenile of O. alexandri and a hydrozoan of the order Leptothecata in the Eastern Pacific. Although this paper documents a significant increase in the number of recorded species in the study area, we highlight the need for a large scale survey in the tropical Mexican Pacific, along with a more thorough sampling on a larger number of substrata in order to increase our knowledge about ophiuroids in the area.

  19. Biologia reprodutiva de Echinometra lucunter (Echinodermata: Echinoidea na Praia da Costa, Vila Velha, Espírito Santo Reproductive biology of Echinometra lucunter (Echinodermata: Echinoidea in Praia da Costa, Vila Velha, Espírito Santo

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    Fátima L. F. Mariante

    2009-12-01

    Full Text Available Echinometra lucunter Linnaeus, 1758 is a tropical sea urchin with strong bioerosive potential. Consequently, this species has great ecological importance. The species occurs in high densities along the Brazilian coast, particularly in the south and southeast. The objective of this work was to evaluate both the effects of annual seasonality and the lunar cycle on the reproduction of E. lucunter. Individuals were sampled monthly for a period of one year and during four complete lunar cycles. The gonadosomatic index (GI was calculated to determine the annual and monthly reproductive peaks based on the lunar phase. The sex ratio (male:female was 1:1.04, without significant difference in sexual proportion. The GI was significantly higher for males than for females. The first sexual maturation occurs when carapace width reaches 23.30 mm, and 50% of the animals have gonads with 28.22 mm. The spawning peak generally occurs during the whole year from the full moon to the waning moon. However, there is an annual reproductive peak from summer to autumn.

  20. Reprodução de Lytechinus variegatus (Echinodermata: Echinoidea: efeito do ciclo lunar e características da população = Reproduction of Lytechinus variegatus (Echinodermata: Echinoidea: effect of lunar cycle and population characteristics

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    Alexandra Mara Cruz Lage

    2011-07-01

    Full Text Available Este estudo avaliou as características reprodutivas de uma população do ouriço do mar Lytechinus variegatus e a influência do ciclo lunar na liberação de gametas. Foram realizadas oito coletas para avaliação do índice gonadossomático (IG e dos parâmetros populacionais relacionados com a reprodução. Para avaliação do efeito da Lua na liberação de gametas foram realizadas coletas em três ciclos lunares completos. Ao todo foram coletados 295 indivíduos, sendo 156 machos e 131 fêmeas (proporção 1,19:1, porém não houve diferença significativa na proporção sexual da população. O peso dos machos foisignificativamente maior que o das fêmeas, porém não houve diferença significativa no IG, peso gonadal e diâmetro entre os sexos. Com a amplitude no diâmetro dos animais coletados (5,5-8,7 cm foram estabelecidas cinco classes de tamanho. Não houve diferençassignificativas no IG entre as classes de tamanho. Houve efeito da periodicidade lunar na liberação de gametas, com menor IG na lua nova, indicando que esta ocorre no primeiro quarto lunar e em marés de sizígia.This work evaluated the spawning of sea urchin Lytechinus variegates based on lunar cycle and population characteristics. Eight monthly collections were realized to estimate the gonadosomatic index (GI and population parameters regarding reproduction. To evaluate the effect of the lunar cycle on spawning, samples were taken for each moon phase of three lunar cycles. In the entire work 295 individuals were collected, 156 males and 131 females (1.19:1 ratio. However, there was no significant difference in the sex ratio of the population. The weight of males was significantly greater than that of females. There were no differences between males and females in gonadosomatic index (GI, gonad weight and diameter. There was aneffect of the lunar periodicity on spawning, with lower GI in new moon, indicating that spawning occurs on the first lunar quarter in spring tide.

  1. Inferring the developmental basis of the sea star abnormality "double ambulacral groove" (Echinodermata: Asteroidea Inferencia sobre la base de desarrollo en estrellas de mar de la anormalidad "doble surco ambulacral" (Echinodermata: Asteroidea

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    FREDERICK H C HOTCHKISS

    2000-12-01

    Full Text Available Very rarely a ray of a sea star is unusually wide and has two parallel ambulacral grooves that extend to a single tip. Such a ray has two terminal plates that are coalesced laterally. This abnormality is inferred to develop as a rare result of regeneration because it is recorded from a species with obligate asexual reproduction (fission and regeneration of halves; no gametes. This conclusion is supported also by an example where the abnormality affects only the distal third of a rayMuy raramente un rayo de estrella de mar es desproporcionadamente ancho y tiene dos surcos ambulacrales paralelos que se extienden hasta su único extremo. Dicho rayo tiene dos placas terminales que coalecen lateralmente. Se ha inferido que esta anormalidad se desarrolla como un resultado raro de regeneración, porque se describe de una especie con reproducción asexual obligada (fisión y regeneración de mitades; no gametos. Además, esta conclusión se sostiene por un ejemplo de anormalidad que afecta sólo el tercio distal de un rayo

  2. A new species of starfish (Echinodermata: Asteroidea from an anchialine cave in the Mexican Caribbean Una especie nueva de estrella de mar (Echinodermata: Asteroidea de una caverna anquialina en el Caribe mexicano

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    Francisco Alonso Solís-Marín

    2010-12-01

    Full Text Available Copidaster cavernicola n. sp. is described from an anchialine cave system in Cozumel, Mexico. Copidaster cavernicola differs from its congeners in having 1-8 papulae in each papular area, and numerous excavate pedicellariae on all surfaces, except between furrow spines and subambulacral spines. C. cavernicola is possibly endemic to the anchialine system which it inhabits.Se describe una especie nueva de la estrella de mar del género Copidaster encontrada en un sistema de cuevas anquihalinas del Caribe, en Cozumel, México. Copidaster cavernicola n. sp. es la primera especie cavernícola de equinodermo que es descrita, y se caracteriza por tener de 1 a 8 pápulas por cada zona papular, numerosos pedicelarios excavados presentes en toda la superficie del cuerpo excepto en el surco ubicado entre las espinas ambulacrales y subambulacrales. Se sugiere que C. cavernicola es una especie endémica propia del sistema anquihalino en el que habita.

  3. Reproductive cycle of Mellita quinquiesperforata (Leske (Echinodermata, Echinoidea in two contrasting beach environments Reprodução de Mellita quinquiesperforata (Leske (Echinodermata, Echinoidea em dois ecossistemas praiais contrastantes

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    Yara A. G. Tavares

    2006-06-01

    Full Text Available The reproductive cycle of the irregular echinoid Mellita quinquiesperforata (Leske, 1778 was studied in populations from two sand beaches with different morphodynamic conditions in Parana coast, from February 1992 through July 1994. Gametogenesis was described by histological and gonad index methods and the differences between both populations were observed in the extension of nutrient storage and spawning period. Both populations exhibited a main reproductive period during spring/summer and a nutrient storage period during autumn/winter months. The spawning period at the intermediate-dissipative beach was shorter than at the reflective beach. Meanwhile, a nutrient storage stage was more extensive in the latter. Gonad index varied between both sexes and it was influenced by population characteristics. Different strategies in allocation of resources between maintenance and reproduction effort (oocyte size confirm the high adaptive plasticity developed by this species to live in contrasting beach environments.O ciclo reprodutivo do equinóide irregular Mellita quinquiesperforata (Leske, 1778 foi estudado em populações de duas praias com diferentes condições morfodinâmicas na costa paranaense, de fevereiro de 1992 a julho de 1994. A gametogênese foi descrita pela análise histológica das gônadas e pela variação do índice gonadal. Foram encontradas diferenças com relação à extensão do período de estocagem de nutrientes e do período de liberação dos gametas nas populações. Ambas exibiram um marcado período reprodutivo na primavera e no verão e uma época de estocagem de nutrientes no outono e no inverno. Na praia intermediária-dissipativa a liberação de gametas ocorreu num período menor do que na reflectiva, porém a fase de acúmulo de reservas nutritivas foi mais extensa na primeira. O índice gonadal apresentou variações entre os sexos e foi influenciado pelas características populacionais. As diferentes estratégias na alocação dos recursos entre manutenção e esforço reprodutivo (tamanho do ovócito confirmam a elevada plasticidade adaptativa desenvolvida pela espécie para habitar ambientes praiais contrastantes.

  4. Deep-water Asteroidea (Echinodermata collected during the TALUD cruises in the Gulf of California, Mexico Asteroidea (Echinodermata de aguas profundas recolectados durante cruceros TALUD en el Golfo de California, México

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    Michel E. Hendrickx

    2011-09-01

    Full Text Available During a series of cruises aboard the R/V "El Puma" aimed at collecting the deep-water benthic and pelagic fauna off the Pacific coast of Mexico, in the eastern Pacific, samples of Asteroidea were collected below 500 m depth (587-1 526 m. A total of 335 specimens were collected, belonging to 18 species, 14 identified to species, 3 to genus, and 1 previously undescribed species. New records are provided for Dipsacaster laetmophilus Fisher, 1910, Myxoderma sacculatum (Fisher, 1905, Peribolaster biserialis Fisher, 1905, Ampheraster chiroplus Fisher, 1928, Ampheraster hyperoncus (H. L. Clark, 1913, Anteliaster coscinactis Fisher, 1923, Nearchaster aciculosus (Fisher, 1910, Ceramaster leptoceramus (Fisher, 1905, Mediaster transfuga Ludwig, 1905, and Lophaster furcilliger Fisher, 1905. All species were collected below the oxygen minimum zone that extends throughout the central and southern Gulf of California, or within the threshold zone where severe to mild hypoxic conditions prevail. Epibenthic dissolved oxygen concentrations associated with the capture of the specimens show support for strong tolerance to severe hypoxia (Durante una serie de campañas oceanográficas realizadas a bordo del B/O "El Puma", enfocadas a la recolección de la fauna bentónica y pelágica de aguas profundas en la costa del Pacífico de México, en el Pacífico oriental, se recolectaron ejemplares de Asteroidea por debajo de 500 m de profundidad (587-1 526 m. Un total de 335 ejemplares fueron recolectados, pertenecientes a 18 especies; 14 fueron determinadas hasta especie, 3 hasta género y 1 especie no descrita. Se proporcionan nuevos registros para Dipsacaster laetmophilus Fisher, 1910, Myxoderma sacculatum (Fisher, 1905, Peribolaster biserialis Fisher, 1905, Ampheraster chiroplus Fisher, 1928, Ampheraster hyperoncus (H. L. Clark, 1913, Anteliaster coscinactis Fisher, 1923, Nearchaster aciculosus (Fisher, 1910, Ceramaster leptoceramus (Fisher, 1905, Mediaster transfuga Ludwig, 1905, y Lophaster furcilliger Fisher, 1905. Todas las especies se recolectaron por debajo de la zona del mínimo de oxígeno que se extiende por las zonas central y sur del golfo de California, o en el umbral de la zona donde prevalecen condiciones de hipoxia de leves a severas. Las concentraciones de oxígeno disuelto epibentónicas asociadas con la captura de los ejemplares indican una fuerte tolerancia a la hipoxia severa (<1,0 ml O2 / l para la mayoría de las especies, y a hipoxia leve para Ctenodiscus crispatus (Retzius, 1805 y Nymphaster diomedeae Ludwig, 1905. Se incluye una lista de todas las especies de asteroideos que se encuentran por debajo de 500 m de profundidad frente a la costa del Pacífico de México.

  5. Distribución, densidad y estructura de talla de Oreaster reticulatus y Luidia senegalensis (Echinodermata: Asteroidea en isla de Cubagua, Venezuela Distribution, density an size structure of Oreaster reticulatus and Luidia senegalensis (Echinodermata: Asteroidea in Cubagua Island, Venezuela

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    Alejandro Tagliafico

    2012-09-01

    Full Text Available Las estrellas de mar: Oreaster reticulatus y Luidia senegalensis, han sido objeto de escasos estudios en aguas venezolanas. Actualmente son consideradas especies amenazadas en diversas zonas del Caribe, Brasil y Colombia. Por esto, se planteó como objetivo generar información sobre su densidad poblacional, distribución y estructura de talla en los alrededores de la isla de Cubagua. Para ello, durante el año 2008, se realizaron cuatro transectas bandas de 50m2 cada una, en 52 estaciones ubicadas alrededor de la isla. Entre los resultados obtenidos para O. reticulatus destacan: 167.3ind/ha, un 33% inmaduros y 67% adultos con un promedio de tallas de 10.7±5cm (rango: 2.2-21cm; una amplia distribución en los alrededores de la isla, con mayores densidades en la zona este y suroeste. Luidia senegalensis mostró una densidad promedio de 40ind/ha, 95% superaba la talla de madurez reportada, con talla promedio de 12cm±3.5cm (rango: 3.5-22.3cm. Se recomienda realizar estudios de reproducción, así como monitoreos de sus densidades poblacionales que permitan inferir sus variaciones temporales.There is limited biological information about the starfish Oreaster reticulatus and the nine-armed starfish Luidia senegalensis in Venezuelan waters. These species are currently considered threatened in many localities of the Caribbean, Brazil and Colombia. Therefore, the aim of this study was to describe their population density, size distribution and population structure in Cubagua Island. During 2008, 52 stations located around the island were evaluated using band transects of 50m2. Each organism was counted and measured (maximum radius, and its size was compared to the maturity length reported in the literature. The results for O. reticulatus include: 167.3ind./ha; 33% juveniles and 67% adults; average size of 10.7±5cm (range: 2.2-21cm; a wide distribution around the island, with higher densities in the Eastern and Southwest areas. The 50% of the specimens were found in seagrass beds, 25% in sand, 16% in areas covered by decomposed seaweeds, 9% in oyster beds and 1% coralline patches. The densities of O. reticulatus were higher than those reported in the Caribbean, Panama and Puerto Rico, but lower than Venezuelan National Parks: Mochima and Morrocoy; as well as in the Virgin Islands and Belize. For L. senegalensis we found an average density of 40ind./ha; 95% exceeded the reported size at maturity, with mean length of 12cm±3.5cm (range: 3.5-22.3cm; they were found only in 15% of the stations of which 92.5% were sandy bottoms and the other 7.5% oyster beds. The degree of aggregation of L. senegalensis was greater than O. reticulatus, with an estimated k of 0.06. However, it was not possible to compare the densities of L. senegalensis with any other study. For both species is recommended to carry out reproductive studies and to monitor their population densities to infer temporal variations.

  6. Estrutura fina do espermatozóide de Mellita quinquiesperforata Leske (Echinodermata do litoral norte do Brasil Fine structure of the spermatozoon of the Mellita quinquiesperforata (Echinodermata of the Northern littoral of Brazil

    Directory of Open Access Journals (Sweden)

    Edilson Matos

    2000-09-01

    Full Text Available The fine structure of the spermatozoon in the Mellita quinquiesperforata Leske, 1778 was studied. Collected from the Amazon region, were described by light and transmission electron microscopy. The spermatozoon consisted of a acrosome complex, nucleus, four to six mitochondria, two centrioles and flagellum. The acrosome was composed of a acrosome complex, the acrosomal vesicle and the subacrosomal space. The nucleus are composed by dense material. The middle piece contains 4-6 mitochondria which are arranged around the centrioles, the 9p+0, whose axoneme has the classic 9p+2 microtubular construction.

  7. OMANASTER IMBRICATUS (ECHINODERMATA, ASTEROIDEA, A NEW GENUS AND SPECIES FROM THE SAKMARIAN (LOWER PERMIAN SAIWAN FORMATION OF OMAN, ARABIAN PENINSULA

    Directory of Open Access Journals (Sweden)

    DANIEL B. BLAKE

    2014-11-01

    Full Text Available Omanaster imbricatus is a new genu s and species of Sakmarian (Early Permian asteroids collected from the basal Pachycyrtella Bed of the Saiwan Formation of Oman, Arabian Peninsula; the family Omanasteridae is recognized. Late Paleozoic and especially Permian asteroids are rare and O. imbricatus differs significantly from those previously described, thereby providing an important addition to known late Paleozoic diversity. Unfortunately the single available specimen is incomplete with remaining ossicles both leached and partially fused, and available data are limited. Adambulacral form and arrangement of O. imbricatus are both suggestive of corresponding expressions of certain earlier Paleozoic species and unlike those of the crown-group, suggesting an enduring Paleozoic lineage but one not phylogenetically a part of the Mesozoic diversification. The Pachycyrtella Bed has been interpreted as recording a succession of pioneer palaeocommunities colonizing a turbulent, shallow-water settingaffected by oscillatory flows. The apparently flattened appearance of O. imbricatus is suggestive of appearances of certain Cretaceous and extant species recovered from similar environments thus suggesting both homoplasy and the versatility of asteroid evolution across extended spans of geologic time.

  8. The aboral ring and the development of early gonads in the echinoid Paracentrotus lividus (Echinodermata, Echinoidea)

    OpenAIRE

    Gosselin, P.; Spirlet, C.; Jangoux, M.

    2003-01-01

    The development of the genital apparatus is described for the echinoid Paracentrotus lividus. This apparatus derives from the aboral ring, an annular structure that includes an inconspicuous coelom and, in juveniles, the germinal rachis. The germinal epithelium grows out from the germinal rachis, and the gonadal wall and coelom in early (tubular) gonads share similarities with their equivalents in the aboral ring. The original germinal rachis regresses to form a genital cord one cell wide in ...

  9. Spatial and seasonal variation of the gonad index of Diadema antillarum (Echinodermata:Echinoidea in the Canary Islands

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    José Carlos Hernández

    2006-12-01

    Full Text Available Diadema antillarum Philippi occurs in high density populations in the Canary Islands, creating extensive barren areas. During one year we determined seasonal changes in the algal abundance and population densities, test diameter, gut contents and gonad index of sea urchins in two localities (Abades and Boca Cangrejo. Boca Cangrejo shows higher algae cover and species richness than Abades. The sea urchin population at Abades had a higher density and smaller urchins than Boca Cangrejo. Boca Cangrejo sea urchins showed higher specific richness in gut contents than Abades urchins. The sea urchin population at Abades did not have a clearer reproductive periodicity or higher gonad index than the Boca Cangrejo population. Temporal and spatial changes in gonad periodicity of Diadema antillarum are attributed, at least in part, to benthic food availability (algal cover and algal species number and intra-specific competition.

  10. Bathyal sea urchins of the Bahamas, with notes on covering behavior in deep sea echinoids (Echinodermata: Echinoidea)

    Science.gov (United States)

    Pawson, David L.; Pawson, Doris J.

    2013-08-01

    In a survey of the bathyal echinoderms of the Bahama Islands region using manned submersibles, approximately 200 species of echinoderms were encountered and documented; 33 species were echinoids, most of them widespread in the general Caribbean area. Three species were found to exhibit covering behavior, the piling of debris on the upper surface of the body. Active covering is common in at least 20 species of shallow-water echinoids, but it has been reliably documented previously only once in deep-sea habitats. Images of covered deep-sea species, and other species of related interest, are provided. Some of the reasons adduced in the past for covering in shallow-water species, such as reduction of incident light intensity, physical camouflage, ballast in turbulent water, protection from desiccation, presumably do not apply in bathyal species. The main reasons for covering in deep, dark, environments are as yet unknown. Some covering behavior in the deep sea may be related to protection of the genital pores, ocular plates, or madreporite. Covering in some deep-sea species may also be merely a tactile reflex action, as some authors have suggested for shallow-water species.

  11. Decline in the species richness contribution of Echinodermata to the macrobenthos in the shelf seas of China

    Science.gov (United States)

    Jin, Shaofei; Wang, Yongli; Xia, Jiangjiang; Xiao, Ning; Zhang, Junlong; Xiong, Zhe

    Echinoderms play crucial roles in the structure of marine macrobenthic communities. They are sensitive to excess absorption of CO2 by the ocean, which induces ocean acidification and ocean warming. In the shelf seas of China, the mean sea surface temperature has a faster warming rate compared with the mean rate of the global ocean, and the apparent decrease in pH is due not only to the increased CO2 absorption in seawater, but also eutrophication. However, little is known about the associated changes in the diversity of echinoderms and their roles in macrobenthic communities in the seas of China. In this study, we conducted a meta-analysis of 77 case studies in 51 papers to examine the changes in the contribution of echinoderm species richness to the macrobenthos in the shelf seas of China since the 1980s. The relative species richness (RSR) was considered as the metric to evaluate these changes. Trends analysis revealed significant declines in RSR in the shelf seas of China, the Yellow Sea, and the East China Sea from 1997 to 2009. Compared with the RSR before 1997, no significant changes in mean RSR were found after 1997, except in the Bohai Sea. In addition, relative change in the RSR of echinoderms and species richness of macrobenthos led to more changes (decrease or increase) in their respective biomasses. Our results imply that changes in species richness may alter the macrobenthic productivity of the marine benthic ecosystem.

  12. Non-destructive morphological observations of the fleshy brittle star, Asteronyx loveni using micro-computed tomography (Echinodermata, Ophiuroidea, Euryalida

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    Massanori Okanishi

    2017-03-01

    Full Text Available The first morphological observation of a euryalid brittle star, Asteronyx loveni, using non-destructive X-ray micro-computed tomography (µCT was performed. The body of euryalids is covered by thick skin, and it is very difficult to observe the ossicles without dissolving the skin. Computed tomography with micrometer resolution (approximately 4.5–15.4 µm was used to construct 3D images of skeletal ossicles and soft tissues in the ophiuroid’s body. Shape and positional arrangement of taxonomically important ossicles were clearly observed without any damage to the body. Detailed pathways inside the vertebral ossicles, lateral arm plates, and arm spines for passage of nerves and water vascular structures were observed. Inter-vertebral muscles were also observed. Forms and 3D arrangements of many important taxonomical characters of the euryalids were scrutinized by µCT in high enough resolution for taxonomic description of ophiuroids.

  13. Reconstructing SALMFamide Neuropeptide Precursor Evolution in the Phylum Echinodermata: Ophiuroid and Crinoid Sequence Data Provide New Insights.

    Science.gov (United States)

    Elphick, Maurice R; Semmens, Dean C; Blowes, Liisa M; Levine, Judith; Lowe, Christopher J; Arnone, Maria I; Clark, Melody S

    2015-01-01

    The SALMFamides are a family of neuropeptides that act as muscle relaxants in echinoderms. Analysis of genome/transcriptome sequence data from the sea urchin Strongylocentrotus purpuratus (Echinoidea), the sea cucumber Apostichopus japonicus (Holothuroidea), and the starfish Patiria miniata (Asteroidea) reveals that in each species there are two types of SALMFamide precursor: an L-type precursor comprising peptides with a C-terminal LxFamide-type motif and an F-type precursor solely or largely comprising peptides with a C-terminal FxFamide-type motif. Here, we have identified transcripts encoding SALMFamide precursors in the brittle star Ophionotus victoriae (Ophiuroidea) and the feather star Antedon mediterranea (Crinoidea). We have also identified SALMFamide precursors in other species belonging to each of the five echinoderm classes. As in S. purpuratus, A. japonicus, and P. miniata, in O. victoriae there is one L-type precursor and one F-type precursor. However, in A. mediterranea only a single SALMFamide precursor was found, comprising two peptides with a LxFamide-type motif, one with a FxFamide-type motif, five with a FxLamide-type motif, and four with a LxLamide-type motif. As crinoids are basal to the Echinozoa (Holothuroidea + Echinoidea) and Asterozoa (Asteroidea + Ophiuroidea) in echinoderm phylogeny, one model of SALMFamide precursor evolution would be that ancestrally there was a single SALMFamide gene encoding a variety of SALMFamides (as in crinoids), which duplicated in a common ancestor of the Echinozoa and Asterozoa and then specialized to encode L-type SALMFamides or F-type SALMFamides. Alternatively, a second SALMFamide precursor may remain to be discovered or may have been lost in crinoids. Further insights will be obtained if SALMFamide receptors are identified, which would provide a molecular basis for experimental analysis of the functional significance of the "cocktails" of SALMFamides that exist in echinoderms.

  14. Reconstructing SALMFamide neuropeptide precursor evolution in the phylum Echinodermata: ophiuroid and crinoid sequence data provide new insights

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    Maurice R Elphick

    2015-02-01

    Full Text Available The SALMFamides are a family of neuropeptides that act as muscle relaxants in echinoderms. Analysis of genome/transcriptome sequence data from the sea urchin Strongylocentrotus purpuratus (Echinoidea, the sea cucumber Apostichopus japonicus (Holothuroidea and the starfish Patiria miniata (Asteroidea reveals that in each species there are two types of SALMFamide precursor: an L-type precursor comprising peptides with a C-terminal LxFamide-type motif and an F-type precursor solely or largely comprising peptides with a C-terminal FxFamide-type motif. Here we have identified transcripts encoding SALMFamide precursors in the brittle star Ophionotus victoriae (Ophiuroidea and the feather star Antedon mediterranea (Crinoidea. We have also identified SALMFamide precursors in other species belonging to each of the five echinoderm classes. As in S. purpuratus, A. japonicus and P. miniata, in O. victoriae there is one L-type precursor and one F-type precursor. However, in A. mediterranea only a single SALMFamide precursor was found, comprising two peptides with a LxFamide-type motif, one with a FxFamide-type motif, five with a FxLamide-type motif and four with a LxLamide-type motif. As crinoids are basal to the Echinozoa (Holothuroidea + Echinoidea and Asterozoa (Asteroidea + Ophiuroidea in echinoderm phylogeny, one model of SALMFamide precursor evolution would be that ancestrally there was a single SALMFamide gene encoding a variety of SALMFamides (as in crinoids, which duplicated in a common ancestor of the Echinozoa and Asterozoa and then specialised to encode L-type SALMFamides or F-type SALMFamides. Alternatively, a second SALMFamide precursor may remain to be discovered or may have been lost in crinoids. Further insights will be obtained if SALMFamide receptors are identified, which would provide a molecular basis for experimental analysis of the functional significance of the cocktails of SALMFamides that exist in echinoderms.

  15. Gametogenesis correlated with steroid levels during the gonadal cycle of the sea urchin Paracentrotus lividus (Echinodermata: Echinoidea).

    Science.gov (United States)

    Barbaglio, Alice; Sugni, Michela; Di Benedetto, Cristiano; Bonasoro, Francesco; Schnell, Sabine; Lavado, Ramon; Porte, Cinta; Candia Carnevali, Daniela M

    2007-06-01

    The specific mechanism regulating reproduction in invertebrates is a field of topical interest which needs to be explored in detail considering also the intriguing possible comparison with vertebrates. In this paper levels of Testosterone (T) and Estradiol (E2) and their reciprocal ratios were determined in ovaries and testis of the echinoid model species Paracentrotus lividus during the year 2004 by taking into account a putative relationship between steroid levels and reproductive cycle. T levels appeared to significantly vary during male reproductive cycle, thus suggesting a possible role of this hormone in regulation of spermatogenesis as demonstrated for other echinoderms. E2 levels were lower in males with respect to females; consequently E2 involvement in oogenesis is hypothesized. In parallel with steroid levels evaluation, variations in P450-aromatase activity and its possible role on regulation of gametogenesis were also considered. Clear correlations between steroid levels and gonad index (GI), as well as between GI and reproductive cycle were not detected, suggesting that GI alone is not a reliable parameter in describing the reproductive status of the gonads. Altogether the results obtained so far confirm the presence of a relationship between steroid levels and reproductive cycle as suggested by previous results on different echinoderm species.

  16. Overview of the Ferdina-like Goniasteridae (Echinodermata: Asteroidea) including a new subfamily, three new genera and fourteen new species.

    Science.gov (United States)

    Mah, Christopher L

    2017-05-25

    Recent assignment of some goniasterid-like Ophidiasteridae into the Goniasteridae has led to further re-evaluation of other ophidiasterids as possible goniasterids. This led to the discovery of new genera and species supported by a distinctive set of characteristics which support a new subfamily, the Ferdininae, a group originally outlined by Marsh and Price (1991) within the Goniasteridae. The historical Ophidiasteridae is paraphyletic and includes several nominal ophidiasterid genera (e.g., Fromia, Neoferdina, etc.). Newly described material has led to the inclusion of six genera,within this group, of which three, Bathyferdina n. gen., Eosaster n. gen., and Kanakaster n. gen., are newly described. Fourteen new species in five genera are described. This includes Bathyferdina aireyae n. gen., n. sp., Eosaster nadiae n. gen., n. sp., Ferdina mena n. sp., Kanakaster balutensis n. gen., n. sp., Kanakaster convexus n. gen., n. sp., Kanakaster discus n. gen., n. sp., Kanakaster larae n. gen., n. sp., Kanakaster plinthinos n. gen., n. sp., Kanakaster solidus n. gen., n. sp., Neoferdina annae n. sp., Neoferdina antigorum, n. sp., Neoferdina momo, n. sp., Neoferdina oni, n. sp., and Paraferdina plakos, n. sp. Identification keys, synopses, and description of these taxa are included.

  17. Brittle stars (Echinodermata: Ophiuroidea) from seamounts in the Andaman Sea (Indian Ocean): first account, with descriptions of new species

    Digital Repository Service at National Institute of Oceanography (India)

    Stohr, S.; Sautya, S.; Ingole, B.S.

    researchers to explore the Andaman Back-arc Basin (ABB), including seamounts. The ABB is an active marginal basin and a 3 part of the major island arc-trench system in the northeastern Indian Ocean. It marks the eastern boundary of the Indian plate where... it sub-ducts beneath the Southeast Asian plate. The German research vessel "Sonne" was used to sample and collect geophysical, geological, chemical and biological data from the Andaman seamounts in 2007 (Sautya et al., 2011). Two seamounts were studied...

  18. Sediment toxicity assessment in the Lagoon of Venice (Italy) using Paracentrotus lividus (Echinodermata: Echinoidea) fertilization and embryo bioassays.

    Science.gov (United States)

    Volpi Ghirardini, A; Arizzi Novelli, A; Tagliapietra, D

    2005-09-01

    The capacity of two toxicity bioassays (fertilization and embryo toxicity tests) to discriminate sediment toxicity using the sea urchin Paracentrotus lividus was tested in five stations with different levels of pollution in the Lagoon of Venice. Two stations were located in estuarine sites, two in the industrial zone, and one in a site at the top of our quality gradient (reference). Elutriate was chosen as sediment matrix to assess the potential effects of bioavailable pollutants in the water column as a consequence of sediment resuspension (dredging and dumping, fishing gear, etc.). An experimental design based on Quality Assurance/Quality Control procedures (QA/QC) was adopted in order to set the methodological basis for an effective use of these bioassays in monitoring programs. Results revealed both higher embriotoxicity than spermiotoxicity in all stations and the efficacy of combined use of both toxicity bioassays in discriminating differing pollution/bioavailability between stations and periods. The good representativeness of the integrated sampling scheme and the standardization of all experimental phases yielded high precision of results. Clear Toxicity Fingerprints were evidenced for the investigated sites through the combined use of both bioassays. A good fit between ecotoxicological data and chemical contamination levels was found, except for unnatural sediment texture.

  19. A new species of deep-water Holothuroidea (Echinodermata of the genus Synallactes from off western Mexico

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    Claude Massin

    2010-08-01

    Full Text Available An undescribed species of Synallactes was collected during a deep-water benthic fauna survey off the Pacific coast of Mexico in the East Pacific, with the R/V El Puma. This new species differs from all the other known Synallactes by the presence of huge massive rods in the tube feet, some of them club-shaped. The later ossicle shape is unique among Holothuroidea. This is the first record of a Synallactes in the Gulf of California.

  20. Functional Morphology of the Arm Spine Joint and Adjacent Structures of the Brittlestar Ophiocomina nigra (Echinodermata: Ophiuroidea)

    Science.gov (United States)

    Wilkie, Iain C.

    2016-01-01

    The skeletal morphology of the arm spine joint of the brittlestar Ophiocomina nigra was examined by scanning electron microscopy and the associated epidermis, connective tissue structures, juxtaligamental system and muscle by optical and transmission electron microscopy. The behaviour of spines in living animals was observed and two experiments were conducted to establish if the spine ligament is mutable collagenous tissue: these determined (1) if animals could detach spines to which plastic tags had been attached and (2) if the extension under constant load of isolated joint preparations was affected by high potassium stimulation. The articulation normally operates as a flexible joint in which the articular surfaces are separated by compliant connective tissue. The articular surfaces comprise a reniform apposition and peg-in-socket mechanical stop, and function primarily to stabilise spines in the erect position. Erect spines can be completely immobilised, which depends on the ligament having mutable tensile properties, as was inferred from the ability of animals to detach tagged spines and the responsiveness of isolated joint preparations to high potassium. The epidermis surrounding the joint has circumferential constrictions that facilitate compression folding and unfolding when the spine is inclined. The interarticular connective tissue is an acellular meshwork of collagen fibril bundles and may serve to reduce frictional forces between the articular surfaces. The ligament consists of parallel bundles of collagen fibrils and 7–14 nm microfibrils. Its passive elastic recoil contributes to the re-erection of inclined spines. The ligament is permeated by cell processes containing large dense-core vesicles, which belong to two types of juxtaligamental cells, one of which is probably peptidergic. The spine muscle consists of obliquely striated myocytes that are linked to the skeleton by extensions of their basement membranes. Muscle contraction may serve mainly to complete the process of spine erection by ensuring close contact between the articular surfaces. PMID:27974856

  1. Megafauna of the UKSRL exploration contract area and eastern Clarion-Clipperton Zone in the Pacific Ocean: Echinodermata.

    Science.gov (United States)

    Amon, Diva J; Ziegler, Amanda F; Kremenetskaia, Antonina; Mah, Christopher L; Mooi, Rich; O'Hara, Tim; Pawson, David L; Roux, Michel; Smith, Craig R

    2017-01-01

    There is growing interest in mining polymetallic nodules from the abyssal Clarion-Clipperton Zone (CCZ) in the tropical Pacific Ocean. Despite being the focus of environmental studies for decades, the benthic megafauna of the CCZ remain poorly known. In order to predict and manage the environmental impacts of mining in the CCZ, baseline knowledge of the megafauna is essential. The ABYSSLINE Project has conducted benthic biological baseline surveys in the UK Seabed Resources Ltd polymetallic-nodule exploration contract area (UK-1). Prior to these research cruises in 2013 and 2015, no biological studies had been done in this area of the eastern CCZ. Using a Remotely Operated Vehicle and Autonomous Underwater Vehicle, the megafauna within the UKSRL exploration contract area (UK-1) and at a site ~250 km east of the UK-1 area were surveyed, allowing us to make the first estimates of megafaunal morphospecies richness from the imagery collected. Here, we present an atlas of the abyssal echinoderm megafauna observed and collected during the ABYSSLINE cruises to the UK-1 polymetallic-nodule exploration contract area in the CCZ. There appear to be at least 62 distinct morphospecies (13 Asteroidea, 5 Crinoidea, 9 Echinoidea, 29 Holothuroidea and 6 Ophiuroidea) identified mostly by imagery but also using molecular barcoding for a limited number of animals that were collected. This atlas will aid the synthesis of megafaunal presence/absence data collected by contractors, scientists and other stakeholders undertaking work in the CCZ, ultimately helping to decipher the biogeography of the megafauna in this threatened habitat.

  2. Fixed, free, and fixed: the fickle phylogeny of extant Crinoidea (Echinodermata) and their Permian-Triassic origin.

    Science.gov (United States)

    Rouse, Greg W; Jermiin, Lars S; Wilson, Nerida G; Eeckhaut, Igor; Lanterbecq, Deborah; Oji, Tatsuo; Young, Craig M; Browning, Teena; Cisternas, Paula; Helgen, Lauren E; Stuckey, Michelle; Messing, Charles G

    2013-01-01

    Although the status of Crinoidea (sea lilies and featherstars) as sister group to all other living echinoderms is well-established, relationships among crinoids, particularly extant forms, are debated. All living species are currently placed in Articulata, which is generally accepted as the only crinoid group to survive the Permian-Triassic extinction event. Recent classifications have recognized five major extant taxa: Isocrinida, Hyocrinida, Bourgueticrinina, Comatulidina and Cyrtocrinida, plus several smaller groups with uncertain taxonomic status, e.g., Guillecrinus, Proisocrinus and Caledonicrinus. Here we infer the phylogeny of extant Crinoidea using three mitochondrial genes and two nuclear genes from 59 crinoid terminals that span the majority of extant crinoid diversity. Although there is poor support for some of the more basal nodes, and some tree topologies varied with the data used and mode of analysis, we obtain several robust results. Cyrtocrinida, Hyocrinida, Isocrinida are all recovered as clades, but two stalked crinoid groups, Bourgueticrinina and Guillecrinina, nest among the featherstars, lending support to an argument that they are paedomorphic forms. Hence, they are reduced to families within Comatulida. Proisocrinus is clearly shown to be part of Isocrinida, and Caledonicrinus may not be a bourgueticrinid. Among comatulids, tree topologies show little congruence with current taxonomy, indicating that much systematic revision is required. Relaxed molecular clock analyses with eight fossil calibration points recover Articulata with a median date to the most recent common ancestor at 231-252mya in the Middle to Upper Triassic. These analyses tend to support the hypothesis that the group is a radiation from a small clade that passed through the Permian-Triassic extinction event rather than several lineages that survived. Our tree topologies show various scenarios for the evolution of stalks and cirri in Articulata, so it is clear that further data and taxon sampling are needed to recover a more robust phylogeny of the group. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Isolation and Characterization of Adhesive Secretion from Cuvierian Tubules of Sea Cucumber Holothuria forskåli (Echinodermata: Holothuroidea

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    Malgorzata Baranowska

    2011-01-01

    Full Text Available The sea cucumber Holothuria forskåli possesses a specialized system called Cuvierian tubules. During mechanical stimulation white filaments (tubules are expelled and become sticky upon contact with any object. We isolated a protein with adhesive properties from protein extracts of Cuvierian tubules from H. forskåli. This protein was identified by antibodies against recombinant precollagen D which is located in the byssal threads of the mussel Mytilus galloprovincialis. To find out the optimal procedure for extraction and purification, the identified protein was isolated by several methods, including electroelution, binding to glass beads, immunoprecipitation, and gel filtration. Antibodies raised against the isolated protein were used for localization of the adhesive protein in Cuvierian tubules. Immunostaining and immunogold electron microscopical studies revealed the strongest immunoreactivity in the mesothelium; this tissue layer is involved in adhesion. Adhesion of Cuvierian tubule extracts was measured on the surface of various materials. The extracted protein showed the strongest adhesion to Teflon surface. Increased adhesion was observed in the presence of potassium and EDTA, while cadmium caused a decrease in adhesion. Addition of antibodies and trypsin abolished the adhesive properties of the extract.

  4. Evaluation of the influence of distinct diets on the survival and growth of the sea urchin Paracentrotus lividus (Echinodermata; Echinoidea)

    National Research Council Canada - National Science Library

    Mafalda, Catarino; Inês, Pires; Susana, Ferreira; Sílvia, Gonçalves

    2014-01-01

    Sea urchins are an expensive delicacy in several regions of the world. Some species, like Paracentrotus lividus, have even been over-exploited in the wild, with relevant declines of their populations...

  5. Evaluation of the influence of distinct diets on the survival and growth of the sea urchin Paracentrotus lividus (Echinodermata; Echinoidea

    Directory of Open Access Journals (Sweden)

    Mafalda Maximino Rojão Sobreiro Catarino

    2014-06-01

    Full Text Available Sea urchins are an expensive delicacy in several regions of the world. Some species, like Paracentrotus lividus, have even been over-exploited in the wild, with relevant declines of their populations. Developing and improving aquaculture techniques, such as suitable feeding diets for their rearing, is therefore necessary. Paracentrotus lividus is preferably herbivorous, feeding mainly on macroalgae. The main objective of this study was to evaluate the influence of 3 different types of diet on the survival and growth of P. lividus: Ulva sp., Asparagopsis armata and animal feed. A total of 45 wild individuals were subjected to an acclimation period at the laboratory. For each diet, 3 replicates, each one consisting of a tank containing 5 individuals, were assembled. The study lasted 6 consecutive weeks, and regular determinations of weight and diameter of the test of each animal, were performed. At the end, the gonadal index was also estimated. Mortality in the 3 diets was not very relevant, and a high survival was therefore observed. The variations in weight were not statistically different, but for the test diameter a small increase in the individuals fed with A. armata was detected. With the animal feed, the values of both variables decreased towards the end of the study. As for the gonadal index, statistical differences between the diets were not obtained. In conclusion, P. lividus adapted easily to captivity and the macroalgae diets were the most favourable for their development. Asparagopsis armata sustained the animals’ growth, while the animal feed proved to be the less suitable diet for P. lividus juveniles. Due to their low cost and ease of harvesting, macroalgal diets may be advantageous for small scale closed systems. Such an option may also assist in the environmental management of coastal areas, since Ulva sp. is abundant in eutrophic systems and A. armata is an invasive species in Europe.

  6. The role of Asterina stellifera (Echinodermata: Asteroidea as a predator in a rocky intertidal community in southern Brazil

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    Patrícia Calil

    2009-06-01

    Full Text Available Populations of Asterina stellifera Möbius, 1859 are declining in southern Brazil and today the species is on the Brazilian list of endangered species. Here we experimentally investigate the ecological role played by A. stellifera as a predator on the rocky substrate community by increasing densities of this species. Starfish taken from other, nearby, locations were added to three replicate plots and their density was maintained every 15 days. None of the total of 32 species that were identified in the encrusting community appeared to be influenced by the experiment. Two species, the barnacle Chthamalus bisinuatus Pilsbry, 1916 and the algae Gracilaria verrucosa (Hudson, showed small apparent responses to predation. We found that A. stellifera only exerts weak predation pressure on the community, even at high densities. This result is strikingly different from that observed for similar species in the northern hemisphere and in Australia.

  7. Influence of Diadema antillarum populations (Echinodermata: Diadematidae on algal community structure in Jardines de la Reina, Cuba

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    Félix Martín Blanco

    2011-09-01

    Full Text Available The 1983-1984 mass mortality of Diadema antillarum produced severe damages on Caribbean reefs contributing to substantial changes in community structure that still persist. Despite the importance of Diadema grazing in structuring coral reefs, available information on current abundances and algal-urchin interactions in Cuba is scarce. We analyzed spatial variations in Diadema abundance and its influence on algal community structure in 22 reef sites in Jardines de la Reina, in June/2004 and April/2005. Urchins were counted in five 30x2m transects per site, and algal coverage was estimated in randomly located 0.25m side quadrats (15 per site. Abundances of Diadema were higher at reef crests (0.013-1.553 ind/m², while reef slope populations showed values up to three orders of magnitude lower and were overgrown by macroalgae (up to 87%, local values. Algal community structure at reef slopes were dominated by macroalgae, especially Dictyota, Lobophora and Halimeda while the most abundant macroalgae at reef crests were Halimeda and Amphiroa. Urchin densities were negatively and positively correlated with mean coverage of macroalgae and crustose coralline algae, respectively, when analyzing data pooled across all sites, but not with data from separate habitats (specially reef crest, suggesting, along with historical fish biomass, that shallow reef community structure is being shaped by the synergistic action of other factors (e.g. fish grazing rather than the influence of Diadema alone. However, we observed clear signs of Diadema grazing at reef crests and decreased macroalgal cover according to 2001 data, what suggest that grazing intensity at this habitat increased at the same time that Diadema recruitment began to be noticeable. Furthermore, the excessive abundance of macroalgae at reef slopes and the scarcity of crustose coralline algae seems to be due by the almost complete absence of D. antillarum at mid depth reefs, where local densities of this urchin were predominantly low. Rev. Biol. Trop. 59 (3: 1149-1163. Epub 2011 September 01.A pesar de la importancia del forrageo de Diadema en la estructuración de los arrecifes de coral, la información disponible sobre la actual abundancia de algas y de las interacciones de erizos en Cuba es escasa. Por lo tanto, se analizan las variaciones espaciales en la abundancia de Diadema antillarum y su influencia sobre las algas en 22 arrecifes en Jardines de la Reina, en junio/2004 y abril/2005. Los erizos se muestrearon en recorridos de 30x2m (5/sitio y las algas en cuadrículas de 0.25m de lado (15/sitio. Las densidades de Diadema fueron mayores en las crestas arrecifales (0.013-1.553ind/m² mientras que las pendientes mostraron valores hasta tres ordenes de magnitud menor y presentaron un cubrimiento excesivo de macroalgas (hasta 87%, siendo las más abundantes Dictyota, Lobophora y Halimeda. Las densidades de erizos estuvieron correlacionadas negativa y positivamente con el cubrimiento de macroalgas y algas costrosas, respectivamente, en el análisis global, pero no en hábitats separados (especialmente en crestas, sugiriendo, conjuntamente con la biomasa histórica de peces, que la estructura de las comunidades en las crestas está determinada por la acción sinérgica de otros factores (herbivoría de peces más que por la influencia de Diadema solo. No obstante, se observaron indicios del forrajeo de Diadema, y el cubrimiento de macroalgas disminuyó desde 2001, lo cual sugiere que la intensidad de la herbivoría aumentó al mismo tiempo que el reclutamiento de Diadema.

  8. Bioerosion caused by the sea urchin Diadema Mexicanum (Echinodermata: Echinoidea) at Bahías de Huatulco, Western Mexico.

    Science.gov (United States)

    Herrera-Escalante, T; López-Pérez, R A; Leyte-Morales, G E

    2005-12-01

    Mexican Pacific sea urchin studies have been focused mainly on species distribution, ecology and fisheries. Reef degradation by sea urchin bioerosion has not been studied previously en these reefs. We investigate the importance of Diadema mexicanum as a bioerosive agent of coral carbonate at Bahias de Huatulco, and the relative magnitude of coral accretion and bioerosion. At each of five localities in Bahias de Huatulco, sea urchin density, feeding and mechanical (spine) erosion was determined for three size class intervals. In general, D. mexicanum do not exert any significant role on coral reef community structure (live coral, dead coral or algal coverage) at the Huatulco area, probably because they are generally small (2.9-4 cm test size) and few in number (1.0-6.8 ind.m-2). Mean bioerosion rates are consistent with those measured for other diadematoids, as well as other urchin species in various eastern Pacific localities. However, the degree of bioerosive impact depends on species, test size, and population density of urchins. Coral carbonate removal by D. mexicanum erosion varies from 0.17 to 3.28 kgCaCO3m(-2)yr(-1). This represents a carbonate loss of < 5% of the annual coral carbonate production at Jicaral Chachacual, San Agustín and Isla Cacaluta, but 16 and 27% at Isla Montosa and La Entrega. On balance, coral accretion exceeds sea urchin erosion at all sites examined at Huatulco. At Bahias de Huatulco coral reef communities are actively growing, though in the coming years, it might be necessary to investigate the local effects of the interaction among erosion, and environmental and human induced perturbations.

  9. Megafauna of the UKSRL exploration contract area and eastern Clarion-Clipperton Zone in the Pacific Ocean: Echinodermata

    Science.gov (United States)

    Ziegler, Amanda F; Kremenetskaia, Antonina; Mah, Christopher L; Mooi, Rich; O'Hara, Tim; Pawson, David L; Roux, Michel; Smith, Craig R

    2017-01-01

    Abstract Background There is growing interest in mining polymetallic nodules from the abyssal Clarion-Clipperton Zone (CCZ) in the tropical Pacific Ocean. Despite being the focus of environmental studies for decades, the benthic megafauna of the CCZ remain poorly known. In order to predict and manage the environmental impacts of mining in the CCZ, baseline knowledge of the megafauna is essential. The ABYSSLINE Project has conducted benthic biological baseline surveys in the UK Seabed Resources Ltd polymetallic-nodule exploration contract area (UK-1). Prior to these research cruises in 2013 and 2015, no biological studies had been done in this area of the eastern CCZ. New information Using a Remotely Operated Vehicle and Autonomous Underwater Vehicle, the megafauna within the UKSRL exploration contract area (UK-1) and at a site ~250 km east of the UK-1 area were surveyed, allowing us to make the first estimates of megafaunal morphospecies richness from the imagery collected. Here, we present an atlas of the abyssal echinoderm megafauna observed and collected during the ABYSSLINE cruises to the UK-1 polymetallic-nodule exploration contract area in the CCZ. There appear to be at least 62 distinct morphospecies (13 Asteroidea, 5 Crinoidea, 9 Echinoidea, 29 Holothuroidea and 6 Ophiuroidea) identified mostly by imagery but also using molecular barcoding for a limited number of animals that were collected. This atlas will aid the synthesis of megafaunal presence/absence data collected by contractors, scientists and other stakeholders undertaking work in the CCZ, ultimately helping to decipher the biogeography of the megafauna in this threatened habitat. PMID:28765722

  10. Late Cretaceous crinoids (Echinodermata) from the southwestern margin of the Holy Cross Mts. (southern Poland) and phylogenetic relationships among bourgueticrinids.

    Science.gov (United States)

    Lach, Rafał; Salamon, Mariusz A

    2016-01-01

    A systematic account of crinoids from the Upper Coniacian-Lower Campanian of the southwestern margin of the Holy Cross Mountains in southern Poland is presented. Seven crinoid taxa [Marsupites testudinarius (von Schlotheim), Bourgueticrinus ellipticus (Miller), Bourgueticrinus sp., I.? granosus Valette, Isocrinus? sp., Nielsenicrinus carinatus Roemer and Austinocrinus bicoronatus (von Hagenow)] are described and illustrated. The new material from Poland extends down the stratigraphic range of Austinocrinus bicoronatus to the Lower Campanian. Morphometric data support that Bourgueticrinus ellipicus and B.? suedicus are conspecific. Taphonomy and paleoecology of recorded crinoid assemblages are discussed. Phylogeny of Cretaceous bourgueticrinids is also revisited.

  11. Impact of diagenetic alteration on sea urchin (Echinodermata) magnesium isotope signatures: Comparison of experimental and fossil data

    Science.gov (United States)

    Riechelmann, Sylvia; Mavromatis, Vasileios; Buhl, Dieter; Dietzel, Martin; Hoffmann, René; Jöns, Niels; Eisenhauer, Anton; Immenhauser, Adrian

    2017-04-01

    Due to their thermodynamically instable high-Mg calcite mineralogy, the skeletal elements of echinoderms are often regarded as unreliable archives of Phanerozoic marine climate dynamics. Nevertheless, traditional and non-traditional isotope and elemental proxy data from echinoderms have been used to reconstruct global changes in palaeoseawater composition (Sandberg-cycles). Recently, these data and the interpretation have been controversially discussed in context with ancient seawater properties. This paper tests the sensitivity of echinoderm skeletal hardparts, specifically sea urchin spines to diagenetic alteration based on magnesium isotope data. We apply a dual approach by: (i) performing hydrothermal alteration experiments using meteoric, marine, and burial reactive fluids; and (ii) comparing these data with fossil sea urchin hardparts. The degree of alteration of experimentally altered and fossil sea urchin hardparts is assessed by a combination of optical (fluorescence, cathodoluminescence (CL), scanning electron microscopy (SEM)) and geochemical tools (elemental distribution, carbon, oxygen and magnesium isotopes). Although initial fluid chemistry of the experiments did not allow the detection of diagenetic overprint by elemental distribution (Fe, Mn) and cathodoluminescence, other tools such as fluorescence, SEM, delta18O, Mg concentration and delta26Mg display alteration effects, which respond to differential fluid temperature, chemistry, and experiment duration time. At experiments run under meteoric conditions with no Mg in the initial fluid, the solid is enriched in the heavier Mg isotopomer due to preferential dissolution of the lighter isotope. In contrast, initial burial and marine fluids have medium to high Mg concentrations. There, the Mg concentration and the delta26Mg values of the altered sea urchin spines increase. Fossil sea urchin hardparts display partly very strong diagenetic overprint as observed by their elemental distribution, cathodoluminescence, delta18O, Mg elemental concentration and delta26Mg. The absence of luminescence might indicate both well-preserved sea urchin spines, but also the secondary enrichment of quenching elements such as iron along diagenetic pathways. The relation between Mg concentration and delta26Mg of the experimentally altered sea urchin spines is in agreement with observations from fossil spines, which also display a 26Mg-enrichment of the solid phase. There, it seems that with increasing degree of alteration, an increase in Mg concentration and delta26Mg occurs. Hence, the experiments performed in this study seem to reflect diagenetic processes under natural conditions. However, the patterns observed are complicated by the interplay of kinetic and thermodynamic processes and the presence of variable amounts of water soluble and water insoluble organic matter within these biominerals. Due to (i) a natural inter- and intra-species variability of the Mg concentration and Mg isotopic composition throughout the echinoderm skeleton and (ii) the fractionation of Mg isotopes during the transformation of ACC as a precursor phase to calcite, the use of delta26Mg values of sea urchin hardparts as a proxy for past seawater delta26Mg is deemed unsuitable. In general, the data shown here are considered significant for those aiming to reconstruct palaeoenvironmental parameters based on echinoderm archives.

  12. Evolutionary history of larval skeletal morphology in sea urchin Echinometridae (Echinoidea: Echinodermata) as deduced from mitochondrial DNA molecular phylogeny.

    Science.gov (United States)

    Kinjo, Sonoko; Shirayama, Yoshihisa; Wada, Hiroshi

    2008-01-01

    The larval skeletons of sea urchins show considerable morphological diversity, even between closely related species, although the evolutionary history and functional significance of this diversity are poorly understood. To infer the evolutionary history of the skeletal morphology, we focused on echinometrid species for which the morphological variation in larval skeletons had been investigated qualitatively and quantitatively. We reconstructed the phylogenetic relationships among 14 echinometrid species based on mitochondrial ND1 and ND2 genes and mapped the morphological characters onto the resultant trees. The monophyly of each genus in the Echinometridae was well supported by our results, as was the close affinity between Colobocentrotus, Heterocentrotus, and Echinometra. The mapping of the morphological characters of the larval skeletons indicated that the length, direction, and density of spines on the postoral rods was well conserved in each group of Echinometridae and that the abundance of spines and the size and shape of the body skeleton changed relatively frequently and hence were less conserved. In Echinometrid species, morphological variation in relatively unconserved features tends to be associated with latitudinal distributions, rather than phylogenetic relationships, indicating that the morphological diversity of larval skeletons could have been caused by adaptation to the habitat environment. Some morphological differences, however, seem to be nonfunctional and generated by the constraints on larval skeletogenesis. Thus, echinometrid species can be a good model with which to study the evolutionary history from both ecological and developmental standpoints.

  13. The Sinbad retrotransposon from the genome of the human blood fluke, Schistosoma mansoni, and the distribution of related Pao-like elements

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    Morales Maria E

    2005-02-01

    Full Text Available Abstract Background Of the major families of long terminal repeat (LTR retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. Results A proviral form of Sinbad, a new LTR retrotransposon, was identified in the genome of S. mansoni. Phylogenetic analysis indicated that Sinbad belongs to one of five discreet subfamilies of Pao/BEL like elements. BLAST searches of whole genomes and EST databases indicated that members of this clade occurred in species of the Insecta, Nematoda, Echinodermata and Chordata, as well as Platyhelminthes, but were absent from all plants, fungi and lower eukaryotes examined. Among the deuterostomes examined, only aquatic species harbored these types of elements. All four species of nematode examined were positive for Sinbad sequences, although among insect and vertebrate genomes, some were positive and some negative. The full length, consensus Sinbad retrotransposon was 6,287 bp long and was flanked at its 5'- and 3'-ends by identical LTRs of 386 bp. Sinbad displayed a triple Cys-His RNA binding motif characteristic of Gag of Pao/BEL-like elements, followed by the enzymatic domains of protease, reverse transcriptase (RT, RNAseH, and integrase, in that order. A phylogenetic tree of deduced RT sequences from 26 elements revealed that Sinbad was most closely related to an unnamed element from the zebrafish Danio rerio and to Saci-1, also from S. mansoni. It was also closely related to Pao from Bombyx mori and to Ninja of Drosophila simulans. Sinbad was only distantly related to the other schistosome LTR retrotransposons Boudicca, Gulliver, Saci-2, Saci-3, and Fugitive, which are gypsy-like. Southern hybridization and bioinformatics analyses indicated that there were about 50 copies of Sinbad in the S. mansoni genome. The presence of ESTs

  14. Conodonts, Calcichordates and the Origin of Vertebrates

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    J. Bergström

    1998-01-01

    Full Text Available Interpretation of early deuterostome evolution and relationships has been hampered by the lack of soft-part preservation in most groups. In addition, a recently revealed upside-down life orientation of vertebrates (the only real notoneuralians compared to other bilateral animals has been misinterpreted as evidence for a unique body design in all deuterostomes, misleading any search for relatives. Regarding echinoderms, the variety of body plans is confusing. The interpretation of some fossils with echinoderm-type calcite skeletons as “calcichordate” ancestors of chordates, however, involves a hypothetical reconstruction of an unusual body plan and a long series of hypothetical transitions. The number of necessary steps is much lower if cephalochordates (amphioxus or lancelet are derived directly from hemichordate enteropneusts. “Sensation interpretations” of fossils (Yunnanozoon, Cathaymyrus from Burgess Shale type deposits have added further confusion. Soft-part preservation of conodont animals, with V-shaped myomeres and a notochord, shows that they were segmented chordates, while probable eyes and teeth suggest that they were already on the vertebrate side. Die Interpretation früher Deuterostomia hinsichtlich ihrer Evolution und verwandtschaftlichen Beziehungen ist in den meisten Gruppen durch den Mangel an Weichkörpererhaltung sehr erschwert. Die kürzlich entdeckte Tatsache, daß Vertebraten, d. h. die einzigen echten Notoneuralia, im Gegensatz zu anderen bilateral symmetrischen Organismen eine mit ihrer ursprünglichen Oberseite nach unten gerichtete Lebensstellung einnehmen, hat zu der irrtümlichen Ansicht geführt, daß alle Deuostomia über einen im Tierreich einzigartigen Bauplan verfügen. Diese Interpretation brachte naturgemäß jede Suche nach Verwandtschaftsverhältnissen auf Abwege. Hinsichtlich der Echinodermata ist die bauplanmäßige Variation in der Tat verwirrend. Die Interpretation einiger Fossilien mit

  15. Contaminant levels in sediments and asteroids (Asterias rubens L., Echinodermata) from the Belgian coast and Scheldt estuary: polychlorinated biphenyls and heavy metals.

    Science.gov (United States)

    Danis, B; Wantier, P; Dutrieux, S; Flammang, R; Dubois, Ph; Warnau, M

    2004-10-15

    The Southern Bight of the North Sea is particularly exposed to anthropogenic contamination, due to heavy urbanisation and industrialisation of its catchment area. The present work focuses on polychlorinated biphenyl (PCB) and metal contamination of the marine environment along and off the Belgian coast. Its objectives were to compare the concentrations of seven PCB congeners and four heavy metals in the sediments (a repository for anthropogenic contaminants) and in the asteroid Asterias rubens (a recognized bioindicator species). Nineteen sampling stations were considered between the mouth of the Scheldt Estuary and the southern limit of the Belgian coast (asteroids were found in 10 out of the 19 stations). PCB and metal concentrations measured in sediments and asteroids were in the range of values reported in previous studies. Stations under direct influence of the Scheldt were the most impacted by the considered contaminants. Metal concentrations varied according to the grain-size fraction considered. In asteroids, PCBs and metals were found to be selectively distributed among body compartments, and pyloric caeca were found to most efficiently discriminate between sampling stations contamination levels. PCB and metal analysis of sediments provided a physicochemical evaluation of the contamination, whereas analysis of asteroids introduced a biological dimension to the approach by taking into account bioavailability of the contaminants.

  16. Preliminary report on Echinoidea and Asteroidea (Echinodermata of the Joint Chilean-German-Italian Magellan Victor Hensen Campaign, 17 October - 25 November 1994

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    Alberto Larraín

    1999-12-01

    Full Text Available Part of the echinoderm material (Echinoidea and Asteroidea sampled by 59 Agassiz trawls during the Victor Hensen Campaign 1994 is summarized in a preliminary species list. In total, 7 echinoids and 21 asteroids have been determined to species from the area between Paso Ancho and Cape Horn. All of them were known from the area before.

  17. On Mellitella stokesii and Amphipholis geminata (Echinodermata, from an intertidal flat in the upper Gulf of Nicoya estuary, Pacific, Costa Rica

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    José A Vargas

    2011-03-01

    Full Text Available Information on changes over time in the biodiversity and ecology of tropical systems is of increasing importance against the background of local, regional, and global dynamics. This study aimed to contribute with long-term data on the abundance fluctuations of two species of echinoderms from a tropical tidal flat. From February 1984 to December 1986, March 1985 to April 1987, and July 1994 to September 1996 (total: 76 dates, core samples (17.7cm², 15cm deep were collected at low tide at a mud-sand flat in the mid upper Gulf of Nicoya estuary, Costa Rica, as part of a survey of the benthic community. Among more than 100 taxa, the burrowing brittle star, Amphipholis geminata, and the sand dollar, Mellitella stokesii, consistently appeared in the samples over the study period. A total of 63 M. stokesii and 149 A. geminata were collected. The 43 sand dollars found during 1984-1985, give an approximate density of 35 ind./m² , which is within the range reported for this species. M. stokesii was almost absent from 1994 to 1996, while A. geminata had its peak of abundance at the end of 1995. Low abundances of the sand dollar during the rainy seasons (May-November and slight increments in dry seasons (December-April cores, also agrees with a report from the region. A. geminata also presented an irregular pattern of abundance, with slight increases at the end of the rainy seasons or during the dry seasons, when higher salinities are more suitable for echinoderms. The patchy spatial distribution of both species makes difficult the detection of patterns with a corer. Nevertheless, this information is unique due to its extensive time coverage and provides a baseline for future surveys designed specifically for the study of tropical intertidal estuarine echinoderms. Rev. Biol. Trop. 59 (1: 193-198. Epub 2011 March 01.La información sobre cambios en el tiempo, en la biodiversidad y ecología de los sistemas tropicales, es de importancia creciente en el contexto de la dinámica local, regional, o global. Este estudio tuvo por objetivo el contribuir con información de largo-plazo sobre fluctuaciones en la abundancia de dos especies de equinodermos en una planicie mareal tropical. De febrero 1984 a diciembre 1986, marzo 1985 a abril 1987, y julio 1994 a septiembre 1996 (total: 76 fechas, muestras de barreno (17.7cm², 15cm de profundidad fueron recolectadas durante la marea baja en una planicie fangosa-arenosa en la región media del estuario del Golfo de Nicoya, Costa Rica, como parte de un estudio de la comunidad bentónica. Entre las más de 100 especies, la estrella frágil excavadora, Amphipholis geminata y la galleta de mar, Mellitella stokesii, aparecieron en las muestras a lo largo del estudio. Un total de 63 M. stokesii, y 149 A. geminata fueron recolectadas. Las 43 galletas de mar encontradas durante 1984-1985, dan una densidad aproximada de 35 ind./m², la que está dentro del ámbito informado para esta especie. M. stokesii estuvo casi ausente entre 1994 y 1996, mientras que A. geminata tuvo su pico de abundancia a fines de 1995. Escasa abundancia de la galleta durante la estación de lluvias (Mayo a Noviembre, y pequeños incrementos durante la estación seca (Diciembre a Abril, también están dentro de lo informado para la región. A. geminata también presentó un patrón irregular de abundancia, con pequeños incrementos durante el fin de la estación de lluvias o durante la estación seca, cuando las salinidades altas son más adecuadas para los equinodermos. La distribución agregada de ambas especies hace difícil la identificación de patrones con el barrreno. No obstante, esta información es única debido a lo amplio de la cobertura temporal, y provee una línea base para futuros muestreos diseñados específicamente para el estudio de los equinodermos estuarinos tropicales de la zona de entre-mareas.

  18. Chronic toxicity test with sea urchin Echinometra lucunter and Lytechinus variegatus (Echinodermata: Echinoidea), exposed to light-stick - flag paternoster used for longline surface fishing

    National Research Council Canada - National Science Library

    Cesar-Ribeiro, Caio; Palanch-Hans, Maria Fernanda

    2010-01-01

    .... The method used was a short chronic toxicity test where embryos of the sea urchins Echinometra lucunter and Lytechinus variegatus were exposed to a stock solution consisting of the supernatant formed...

  19. Crinoids columnals (Echinodermata) of the Ererê Formation (late Eifelian-early Givetian, Amazon Basin), State of Pará, Brazil

    Science.gov (United States)

    Scheffler, S. M.; Fernandes, A. C. S. F.; da Fonseca, V. M. M.

    2014-01-01

    The faunal composition of stalked echinoderms in the Brazilian Devonian is still largely unknown despite the great abundance of crinoids in the shallow epicontinental seas of the Paleozoic. The first Devonian crinoids of Brazil, recorded in the literature in 1875 and 1903, were from the sedimentary rocks of the Ererê Formation in the Amazon Basin. Since then, the echinoderms of this formation have not been studied. This study, based on isolated pluricolumnals and columnals, described and identified Botryocrinus meloi n. sp., the first record for this genus in Brazil. In addition to this species, two other morphological patterns were identified: Tjeecrinus sp. and Morphotype AM/Er-01. The form of occurrence of the crinoid material and the paleoautoecology of B. meloi allow preliminary characterization of the habitat as a moderately deep water with weak to moderate currents and soft substrate. The similarity between B. meloi and Botryocrinus montguyonensis and of Tjeecrinus? sp. and T. crassijugatus, from the Devonian of the Armorican and Rhenan Massif, represents new evidence for the existence of contact between the faunas of the Amazon Basin with those of northern Gondwana and Armorica during the Middle Devonian.

  20. The impact of oil-derived products on the behaviour and biochemistry of the eleven-armed asteroid Coscinasterias muricata (Echinodermata).

    Science.gov (United States)

    Georgiades, E T; Holdway, D A; Brennan, S E; Butty, J S; Temara, A

    2003-04-01

    The present study examines the impact of exposure to oil-derived products on the behaviour and physiology of the Australian 11-armed asteroid Coscinasterias muricata. Asteroids were exposed to dilutions of water-accommodated fraction (WAF) of Bass Strait stabilised crude oil, dispersed oil or burnt oil (n = 8) for 4 days whereby, prey-localisation behaviour was examined immediately after exposure, and following 2, 7, and 14 days depuration in clean seawater. The prey-localisation behaviour of asteroids exposed to WAF and dispersed oil was significantly affected though recovery was apparent following 7 and 14 days depuration, respectively. In contrast, there was no significant change in the prey-localisation behaviour of asteroids exposed to burnt oil. Behavioural impacts were correlated with the total petroleum hydrocarbon concentrations (C6-C36) in each exposure solution, WAF (1.8 mg l(-1)), dispersed oil (3.5 mg l(-1)) and burnt oil (1.14 mg l(-1), respectively. The total microsomal cytochrome P450 content was significantly lower (P(Dunnett test) asteroids exposed to dispersed oil than in any other asteroids, whilst asteroid alkaline phosphatase activity was not significantly affected (P(ANOVA) = 0.11). This study further documents the deleterious impact of dispersed oil to marine organisms and supports further research in the area of in situ burning as a less damaging oil spill response measure towards benthic macro-invertebrates.

  1. Mechanical properties of the compass depressors of the sea-urchin Paracentrotus lividus (Echinodermata, Echinoidea and the effects of enzymes, neurotransmitters and synthetic tensilin-like protein.

    Directory of Open Access Journals (Sweden)

    Iain C Wilkie

    Full Text Available The compass depressors (CDs of the sea-urchin lantern are ligaments consisting mainly of discontinuous collagen fibrils associated with a small population of myocytes. They are mutable collagenous structures, which can change their mechanical properties rapidly and reversibly under nervous control. The aims of this investigation were to characterise the baseline (i.e. unmanipulated static mechanical properties of the CDs of Paracentrotus lividus by means of creep tests and incremental force-extension tests, and to determine the effects on their mechanical behaviour of a range of agents. Under constant load the CDs exhibited a three-phase creep curve, the mean coefficient of viscosity being 561±365 MPa.s. The stress-strain curve showed toe, linear and yield regions; the mean strain at the toe-linear inflection was 0.86±0.61; the mean Young's modulus was 18.62±10.30 MPa; and the mean tensile strength was 8.14±5.73 MPa. Hyaluronidase from Streptomyces hyalurolyticus had no effect on creep behaviour, whilst chondroitinase ABC prolonged primary creep but had no effect on secondary creep or on any force-extension parameters; it thus appears that neither hyaluronic acid nor sulphated glycosaminoglycans have an interfibrillar load transfer function in the CD. Acetylcholine, the muscarinic agonists arecoline and methacholine, and the nicotinic agonists nicotine and 1-[1-(3,4-dimethyl-phenyl-ethyl]-piperazine produced an abrupt increase in CD viscosity; the CDs were not differentially sensitive to muscarinic or nicotinic agonists. CDs showed either no, or no consistent, response to adrenaline, L-glutamic acid, 5-hydroxytryptamine and γ-aminobutyric acid. Synthetic echinoid tensilin-like protein had a weak and inconsistent stiffening effect, indicating that, in contrast to holothurian tensilins, the echinoid molecule may not be involved in the regulation of collagenous tissue tensility. We compare in detail the mechanical behaviour of the CD with that of mammalian tendon and highlight its potential as a model system for investigating poorly understood aspects of the ontogeny and phylogeny of vertebrate collagenous tissues.

  2. Chronic toxicity test with sea urchin Echinometra lucunter and Lytechinus variegatus (Echinodermata: Echinoidea, exposed to light-stick - flag paternoster used for longline surface fishing

    Directory of Open Access Journals (Sweden)

    Caio Cesar-Ribeiro

    2010-06-01

    Full Text Available In this work, the chronic toxicity of a mixture of light-stick chemicals and water was tested. The light-stick is used in fishery activities to catch swordfish. The tubes were collected on the beaches of the Costa dos Coqueiros - BA, Brazil, in the period from 14th to 31st July 2007. The method used was a short chronic toxicity test where embryos of the sea urchins Echinometra lucunter and Lytechinus variegatus were exposed to a stock solution consisting of the supernatant formed from a mixture of sea water and the orange-colored light-stick chemical. After a preliminary test, concentrations defined were 0.002, 0.003, 0.01, 0.02, 0.1, 1.0% of stock solution. The final test ran for 36 hours for E. Lucunter and 24 hours for L. variegatus with 4 replicates for each concentration. The value of EC50 - 36h was 0.062% with confidence limits ranging from 0.042 to 0.079% and the EC50 - 24h was 0.011% with confidence limits ranging from 0.009 to 0.014%, i.e., the chemical mix present in the light-stick is potentially toxic. So, as these flags are commonly used for fishing there is potential danger in their disposal in the open ocean.O objetivo deste trabalho foi avaliar a toxicidade crônica da água do mar em contato com o líquido contido no light-stick, sinalizador utilizado em pesca de espinhel de superfície para a captura de espadarte. Os tubos foram coletados nas praias da Costa dos Coqueiros - BA, no período de 14 a 31 de Julho de 2007. O método utilizado para a verificação da toxicidade crônica foi o teste de curta duração com embriões de ouriço-do-mar Echinometra lucunter e Lytechinus variegatus, os ensaios foram realizados com solução estoque que consiste do sobrenadante formado a partir de uma mistura de água do mar com o líquido do sinalizador de coloração laranja. Após um teste preliminar as concentrações definidas foram 0.002; 0.003; 0.01; 0.02; 0.1; 1.0%. O teste definitivo teve duração de 36 horas para E. lucunter e 24 horas para L. variegatus, sendo preparadas 4 réplicas para cada concentração. O valor da CE50 - 36h encontrado foi de 0.062% com limites de aceitabilidade variando de 0.042 a 0.079% e a CE50 - 24h encontrada foi de 0.011% com limites de aceitabilidade variando de 0.009 a 0.014%, ou seja, os compostos químicos presentes no light-stick são potencialmente tóxicos. Portanto já que esses sinalizadores são utilizados comumente como petrechos de pesca há a necessidade de que eles sejam recolhidos, pois podem causar efeitos adversos quando abrem nos oceanos.

  3. Reproductive cycle of Loxechinus albus (Echinodermata: Echinoidea in two areas of the Magellan Region (53ºS, 70-72ºW, Chile

    Directory of Open Access Journals (Sweden)

    Sylvia T. Oyarzún

    1999-12-01

    Full Text Available The reproductive cycle of the Chilean edible sea urchin, Loxechinus albus, was studied in two areas of the Magellan region, the Cockburn Channel (53°43´S, 70°42´W and Dawson Island (53°43´S, 72°00´W. Eleven monthly samplings were carried out from April 1996 to May 1997 in each area and samples of between 88 and 100 organisms were collected. Test diameter, total wet weight, and wet gonad weight was measured for each organism. Sex, gonad index, maturity index and gametogenic condition were estimated for each organism through histological analyses. The results indicate that L. albus in the Magellan region has an annual reproductive cycle in which the temporal sequence of different gametogenic processes can not be distinguished accurately due to the rapid and continuous gonadal recovery and gamete production after the spawning period. Although mature organisms were present most of the year, simultaneous spawning of males and females occurred from August to September in Dawson Island and from July to September in the Cockburn Channel. Gametes of those organisms that became mature after the spawning period were resorbed by nutritive phagocytes. Results from this study suggest that small-scale variability of spawning period in the Magellan region may be explained by the differences in food type and availability among areas. Our results also suggest that the Magellan region is an exception to the latitudinal pattern of spawning period reported for most of the Chilean coast. This large-scale variability may be explained by the simultaneous occurrence of low temperatures and short days during late winter and early spring.

  4. Density of Diadema antillarum (Echinodermata: Echinoidea) on live coral patch reefs and dead Acropora cervicornis rubble patches near Loggerhead Key, Dry Tortugas National Park, Florida, USA

    Science.gov (United States)

    Density of adult Diadema antillarum was assessed on live coral patch reefs and dead Acropora cervicornis rubble patches next to Loggerhead Key, Dry Tortugas National Park, Florida, USA in June 2009. Mean density on live coral patch reefs (0.49 individuals m-2) was not statistical...

  5. Did vicariance and adaptation drive cryptic speciation and evolution of brooding in Ophioderma longicauda (Echinodermata: Ophiuroidea), a common Atlanto-Mediterranean ophiuroid?

    Science.gov (United States)

    Boissin, E; Stöhr, S; Chenuil, A

    2011-11-01

    Over the last decade, cryptic speciation has been discovered in an increasing number of taxa. Species complexes are useful models for the understanding of speciation processes. Motivated by the discovery of brooding specimens in the common Atlanto-Mediterranean broadcast spawning brittle star, Ophioderma longicauda, a recent study revealed the occurrence of divergent mitochondrial lineages. We analysed 218 specimens from 23 locations spread over the geographic range of the species with partial Cytochrome c Oxidase subunit I (COI) sequences. A subset of this sample was also surveyed with the internal transcribed spacer of the ribosomal DNA cluster (nuclear ITS-1). Our study revealed six highly divergent mitochondrial lineages, and the ITS-1 data confirmed that they most likely represent a species complex. Geographic ranges, abundances and genetic structures are contrasted among the putative cryptic species. Lineages in which brooding specimens have been found form a monophyletic group and are restricted to the Eastern Mediterranean basin, an oligotrophic zone. A phylogeny-trait association analysis revealed a phylogenetic signal for low 'chlorophyll a' values (our proxy for oligotrophy). An ecological shift related to the hyper oligotrophy of the Eastern Mediterranean region is therefore likely to have played a role in the evolution of brooding. This study revealed that a complex mixture of vicariance, population expansion, adaptive divergence and possibly high local diversification rates resulting from brooding has shaped the evolution of this species complex. The dating analysis showed that these events probably occurred in the Pleistocene epoch. © 2011 Blackwell Publishing Ltd.

  6. The Effect of Photobiomodulation on the Sea Urchin Paracentrotus lividus (Echinodermata) Using Higher-Fluence on Fertilization, Embryogenesis, and Larval Development: An In Vitro Study.

    Science.gov (United States)

    Amaroli, Andrea; Gambardella, Chiara; Ferrando, Sara; Hanna, Reem; Benedicenti, Alberico; Gallus, Lorenzo; Faimali, Marco; Benedicenti, Stefano

    2017-03-01

    The aim of this study was to investigate the photobiomodulation (PBM) effect of the 808 nm diode laser irradiation on spermatozoa, eggs, fertilized eggs, embryos, and larvae of Paracentrotus lividus, using two different power settings. Studies have shown the possible use of PBM in artificial insemination. These have shown the potential effect of low-power laser irradiation on spermatozoa, while there are few studies on the effect of laser photonic energy on oocytes and almost no reports on the influence of lasers in embryogenesis. P. lividus gametes, zygotes, embryos, and larvae were irradiated using the 808 nm diode laser (fluence 64 J/cm2 using 1 W or 192 J/cm2 with 3 W) with a flat-top hand-piece delivery, compared to a control without laser irradiation (0 J/cm2-0 W). The fertilization rate and the early developmental stages were investigated. The fertilization ability was not affected by the sperm/egg irradiation. At the gastrula stage, no significant differences were observed compared with the control samples. In the late pluteus stage, there were no differences in the developmental percentage observed between the control and the treated samples (1 W), with the exception of larvae from gastrulae and larvae, which were irradiated at 3 W. This study has demonstrated that both the 64 J/cm2-1 W and the 192 J/cm2-3 W do not induce morphological damage on the irradiated P. lividus gametes whose zygotes generate normal embryos and larvae. Our data therefore support the assumption to use higher fluence in preliminary studies on in vitro fertilization.

  7. A new species of Western Atlantic sea lily in the family Bathycrinidae (Echinodermata: Crinoidea), with a discussion of relationships between crinoids with xenomorphic stalks.

    Science.gov (United States)

    Mironov, Alexandr N; Pawson, David L

    2014-10-16

    A new species in the family Bathycrinidae is described from abyssal depths from the Bahamas. It is referred to the recently established genus Discolocrinus, which formerly comprised a single species D. thieli Mironov, 2008 from the Eastern Pacific. Discolocrinus iselini n. sp. is characterized by large body size, high tegmen with tube-like upper region, extremely elongated IBr1 and IBr2, large knobby processes on primibrachials, and overgrowth of soft tissue on the pinnules, the tissue containing numerous perforated or imperforate ossicles of varying size and form. Differences between Discolocrinus and other bathycrinids may seem to be of taxonomic importance at the family level, but knowledge of the morphology and variability of both species of Discolocrinus is incomplete and, until a richer material becomes available, the genus should remain in family Bathycrinidae. Representatives of five families with xenomorphic stalks were examined to characterize the genera on the basis of number or form of knobby processes. These processes occur in two families with differing external morphology: ten-armed Bathycrinidae and five-armed Bourgueticrinidae. They also occur in the comatulid family Atelecrinidae. This similarity might seem to indicate a close relationship between the three families. However, morphological analysis supports the separation of the families Caledonicrinidae and Septocrinidae from Bathycrinidae despite the fact that they share a xenomorphic stalk and IBr2ax. These conclusions are in agreement with results of recent molecular studies.

  8. On Mellitella stokesii and Amphipholis geminata (Echinodermata), from an intertidal flat in the upper Gulf of Nicoya estuary, Pacific, Costa Rica.

    Science.gov (United States)

    Vargas, José A; Solano, Sylvia

    2011-03-01

    Information on changes over time in the biodiversity and ecology of tropical systems is of increasing importance against the background of local, regional, and global dynamics. This study aimed to contribute with long-term data on the abundance fluctuations of two species of echinoderms from a tropical tidal flat. From February 1984 to December 1986, March 1985 to April 1987, and July 1994 to September 1996 (total: 76 dates), core samples (17.7 cm2, 15 cm deep) were collected at low tide at a mud-sand flat in the mid upper Gulf of Nicoya estuary, Costa Rica, as part of a survey of the benthic community. Among more than 100 taxa, the burrowing brittle star, Amphipholis geminata, and the sand dollar, Mellitella stokesii, consistently appeared in the samples over the study period. A total of 63 M. stokesii and 149 A. geminata were collected. The 43 sand dollars found during 1984-1985, give an approximate density of 35 ind./m2, which is within the range reported for this species. M. stokesii was almost absent from 1994 to 1996, while A. geminata had its peak of abundance at the end of 1995. Low abundances of the sand dollar during the rainy seasons (May-November) and slight increments in dry seasons (December-April) cores, also agrees with a report from the region. A. geminata also presented an irregular pattern of abundance, with slight increases at the end of the rainy seasons or during the dry seasons, when higher salinities are more suitable for echinoderms. The patchy spatial distribution of both species makes difficult the detection of patterns with a corer. Nevertheless, this information is unique due to its extensive time coverage and provides a baseline for future surveys designed specifically for the study of tropical intertidal estuarine echinoderms.

  9. A taxonomic guide to the brittle-stars (Echinodermata, Ophiuroidea) from the State of Paraíba continental shelf, Northeastern Brazil

    Science.gov (United States)

    Gondim, Anne I.; Alonso, Carmen; Dias, Thelma L. P.; Manso, Cynthia L. C.; Christoffersen, Martin L.

    2013-01-01

    Abstract We provide the first annotated checklist of ophiuroids from the continental shelf of the State of Paraíba, northeastern Brazil. Identification keys and taxonomic diagnoses for 23 species, belonging to 14 genera and 8 families, are provided. The material is deposited in the Invertebrate Collection Paulo Young, at the Federal University of Paraíba. Ophiopsila hartmeyeri represents the first record for the northeastern region of Brazil, while Ophiolepis impressa, Ophiolepis paucispina, Amphiura stimpsoni, Amphiodia riisei, Ophiactis quinqueradia, Ophiocoma wendtii and Ophionereis olivaceae are new records for the State of Paraíba. The number of species known for the state was increased from 16 to 23, representing approximately 17% of the species known for Brazil and 54% of the species known for northeastern Brazil. The recorded fauna has a large geographical and bathymetrical distribution. PMID:23794923

  10. Two new species of Syndesmis (Platyhelminthes, Rhabdocoela, Umagillidae from the sea urchin Pseudechinus magellanicus (Echinodermata, Echinoidea in the Southwestern Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    Francisco Brusa

    2017-08-01

    Full Text Available In this paper, we describe two new species of Syndesmis living in Pseudechinus magellanicus in the Southwest Atlantic Ocean. The new species have a long stylet in the male reproductive system, which is different from that of the known species of the genus. Specimens of Syndesmis selknami n. sp. have a ∼220-μm-long stylet (∼1/3 of the body length, 0.69 mm. This ratio is unique because only four species (Syndesmis echinorum, Syndesmis rubida, Syndesmis inconspicua and Syndesmis echiniacuti have similar stylet lengths but are larger in body sizes (3–5 mm. Specimens of Syndesmis aonikenki n. sp. have a ∼148-μm-long stylet (∼1/10 of the body length, 1.11 mm. Syndesmis pallida has a similar ratio but the uterus is located posteriorly, and the filament glands are very small and located in the posterior region of the body. These are the first flatworms reported parasitizing Pseudechinus magellanicus.

  11. Evidence for cospeciation events in the host-symbiont system involving crinoids (Echinodermata) and their obligate associates, the myzostomids (Myzostomida, Annelida).

    Science.gov (United States)

    Lanterbecq, Déborah; Rouse, Grey W; Eeckhaut, Igor

    2010-02-01

    Although molecular-based phylogenetic studies of hosts and their associates are increasingly common in the literature, no study to date has examined the hypothesis of coevolutionary process between hosts and commensals in the marine environment. The present work investigates the phylogenetic relationships among 16 species of obligate symbiont marine worms (Myzostomida) and their echinoderm hosts (Crinoidea) in order to estimate the phylogenetic congruence existing between the two lineages. The combination of a high species diversity in myzostomids, their host specificity, their wide variety of lifestyles and body shapes, and millions years of association, raises many questions about the underlying mechanisms triggering their diversification. The phylogenetic relationships, inferred using a three-genes dataset (18S rDNA, 16S rDNA, and COI) and two-genes dataset (18S rDNA, and COI) for the myzostomids and crinoids, respectively, were congruent with the literature. The overall congruence between the two phylogenies was statistically significant according to topology-based, distance-based, and data-based approaches: a significant pattern of cophylogeny was found, though not perfect probably resulting from occasional host switches, duplications or extinction events. A minimum of 8 cospeciation events was estimated, which is significantly higher than it would have been expected due to chance alone. Copyright (c) 2009. Published by Elsevier Inc.

  12. Les étoiles de mer (Echinodermata: Asteroidea) récoltées par le M/V Calamar au large des Guyanes et du Venezuela

    NARCIS (Netherlands)

    Jangoux, Michel

    1978-01-01

    Fourteen species of starfish are recorded from the sea off the Guyanas and Venezuela. Most of them are shallow-water animals including two uncommon forms, Chaetaster nodosus Perrier and Verrillaster spinulosus (Verrill). Two interesting deep-sea starfishes were collected, viz. Cheiraster planus

  13. Development and Application of Genetic Markers for Population Structure Analysis of the Blue Coral Reef Starfish, Linckia laevigata (Linn. (Echinodermata: Asteroidea

    Directory of Open Access Journals (Sweden)

    Richard Magsino

    2000-12-01

    Full Text Available The tropical blue coral reef starfish, Linckia laevigata, is a good model species for examining genetic affinities among reef populations. Allozyme and mtDNA PCR-RFLP genetic markers were developed for this species. A total of nine (9 polymorphic and three (3 monomorphic allozyme marker loci were resolved out of 25 enzyme systems assessed for genetic activity in three electrophoretic buffers used. Polymorphic mitochondrial DNA gene segments of the control region with flanking sequences and the cytochrome oxidase I (CO1 were amplified after examining several gene regions for PCR product amplifications. Restriction enzyme screening of the CO1 region revealed variation of restriction profiles in seven (7 out of twenty (20 enzymes initially tested. Preliminary comparison of the genetic structure of L. laevigata based on allozyme and mtDNA markers for selected reefs are presented. The development of these genetic markers will be useful in inferring gene flow and reef connectivity in the South China Sea, Palawan shelf, and Sulu Sea.

  14. Physiological and immunocytochemical evidence that glutamatergic neurotransmission is involved in the activation of arm autotomy in the featherstar Antedon mediterranea (Echinodermata: Crinoidea).

    Science.gov (United States)

    Wilkie, I C; Barbaglio, A; Maclaren, W M; Carnevali, M D Candia

    2010-06-15

    The crinoid echinoderm Antedon mediterranea autotomises its arms at specialised skeletal joints known as syzygies that occur at regular intervals along the length of each arm. Detachment is achieved through the nervously mediated destabilisation of ligament fibres at a particular syzygy. The aim of this investigation was to identify neurotransmitters that are involved in the autotomy response. Physiological experiments were conducted on isolated preparations of syzygial joints, which can be induced to undergo autotomy-like fracture by applying stimulatory agents such as elevated [K(+)](o). Initial experiments with elevated [K(+)](o) showed that the autotomy threshold (the minimum amount of stimulation required to provoke autotomy) is lowest in syzygies at the arm base and rises distally. Of a range of neurotransmitter agonists tested, only l-glutamate invoked syzygial destabilisation, as did its analogues l-aspartate, alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) and kainate, but not l-(+)-2-amino-4-phosphonobutyrate (l-AP4) or N-methyl-d-aspartate (NMDA). The implication that l-glutamate stimulates syzygial fracture through AMPA/kainate-like receptors was supported by the finding that the action of l-glutamate was inhibited by the AMPA/kainate receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). Acetylcholine depressed the response of syzygial preparations to l-glutamate, suggesting a possible mechanism by which the autotomy threshold could be varied constitutively and facultatively. An immunocytochemical method employing a polyclonal antibody against l-glutamate conjugated to glutaraldehyde revealed l-glutamate-like immunoreactivity in all components of the putative neural pathway controlling the autotomy reflex, including the epidermis, brachial nerve, syzygial nerves and cellular elements close to the syzygial ligaments. We conclude that it is highly probable that l-glutamate acts as an excitatory neurotransmitter in the activation of arm autotomy in A. mediterranea.

  15. Distribución, densidad y estructura de talla de Oreaster reticulatus y Luidia senegalensis (Echinodermata: Asteroidea en isla de Cubagua, Venezuela

    Directory of Open Access Journals (Sweden)

    Alejandro Tagliafico

    2012-09-01

    Full Text Available Las estrellas de mar: Oreaster reticulatus y Luidia senegalensis, han sido objeto de escasos estudios en aguas venezolanas. Actualmente son consideradas especies amenazadas en diversas zonas del Caribe, Brasil y Colombia. Por esto, se planteó como objetivo generar información sobre su densidad poblacional, distribución y estructura de talla en los alrededores de la isla de Cubagua. Para ello, durante el año 2008, se realizaron cuatro transectas bandas de 50m2 cada una, en 52 estaciones ubicadas alrededor de la isla. Entre los resultados obtenidos para O. reticulatus destacan: 167.3ind/ha, un 33% inmaduros y 67% adultos con un promedio de tallas de 10.7±5cm (rango: 2.2-21cm; una amplia distribución en los alrededores de la isla, con mayores densidades en la zona este y suroeste. Luidia senegalensis mostró una densidad promedio de 40ind/ha, 95% superaba la talla de madurez reportada, con talla promedio de 12cm±3.5cm (rango: 3.5-22.3cm. Se recomienda realizar estudios de reproducción, así como monitoreos de sus densidades poblacionales que permitan inferir sus variaciones temporales.

  16. TEMPERATURE RELATIONS OF CENTRAL OREGON MARINE INTERTIDAL INVERTEBRATES.

    Science.gov (United States)

    MARINE BIOLOGY, OREGON), (* INVERTEBRATES , ECOLOGY), SEA WATER, TIDES, SURFACE TEMPERATURE, DIURNAL VARIATIONS, TEMPERATURE, ECHINODERMATA, GASTROPODA, PELECYPODA, BARNACLES, SALINITY, REPRODUCTION(PHYSIOLOGY)

  17. the role of jakara dam in the transmission of schistosomiasis 58

    African Journals Online (AJOL)

    DR. AMINU

    Bilharz, Biomphalaria pfeffeiri Krauss, the intermediate host of S. mansoni Sambon and Lymnea natalensis Krauss, the intermediate host of Fasiola gigantica Cobbold , P..conica and Bithynia tentaculata were encountered and investigated for trematode infections. B. globosus was the most frequently encountered in the two ...

  18. Temporary expansion to shelf depths rather than an onshore-offshore trend: the shallow-water rise and demise of the modern deep-sea brittle star family Ophiacanthidae (Echinodermata: Ophiuroidea

    Directory of Open Access Journals (Sweden)

    Ben Thuy

    2013-07-01

    Full Text Available Hypotheses on the age and possible antiquity of the modern deep-sea fauna put forward to date almost all agree on the assumption that the deep-sea fauna is largely the result of colonisation from shallow-water environments. Here, the fossil record of the Ophiacanthidae, a modern deep-sea brittle star family with extensive fossil occurrences at shelf depths, is systematically traced against a calibrated phylogeny. Several lines of evidence suggest that the Ophiacanthidae originated and greatly diversified in the deep sea, with most extant clades having diverged by the end of the Triassic at the latest. During the Jurassic, the family temporarily invaded shelf environments, attaining relative abundances and diversities comparable to those found in coeval and modern deep-sea settings, and gradually declined in abundance subsequently, to become largely restricted to the deep-sea again. The pattern of temporary expansion to shelf environments suggested here underpins the potential of deep-sea environments to contribute significantly to shallow-water biodiversity; an aspect that has mostly been neglected so far. It is speculated that the large-scale ophiacanthid invasion of shelf environments around the Triassic-Jurassic boundary was initiated by a change from thermohaline to halothermal circulation, attenuating the thermal stratification of the water column and thus providing opportunities for enhanced vertical migration of marine taxa.

  19. Adipokinetic hormones and their G protein-coupled receptors emerged in Lophotrochozoa

    DEFF Research Database (Denmark)

    Li, Shizhong; Hauser, Frank; Skadborg, Signe K.

    2016-01-01

    the neuropeptide systems used by proto- or deuterostomes. An exception, however, are members of the gonadotropin-releasing hormone (GnRH) receptor superfamily, which occur in both evolutionary lineages, where GnRHs are the ligands in Deuterostomia and GnRH-like peptides, adipokinetic hormone (AKH), corazonin...

  20. Antifouling activity of Indian marine invertebrate against the green mussel Perna viridis L.

    Digital Repository Service at National Institute of Oceanography (India)

    PrabhaDevi; Jayasree, V.; Naik, C.G.; Parameswaran, P.S.; Raveendran, T.V.; Kamat, S.Y.

    Thirty-one species of marine invertebrates collected from the Indian Coast, belonging to six phyla (Porifera, Coelenterata, Annelida, Mollusca, Echinodermata, and Eurochordata) were tested for antifouling activity against the green mussel Perna...

  1. African Zoology - Vol 31, No 2 (1996)

    African Journals Online (AJOL)

    Feeding, tentacle and gut morphology in five species of southern African intertidal holothuroids (Echinodermata) · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Greg G. Foster, Alan N. Hodgson, 70-79 ...

  2. A new southern African genus in the holothurian family ...

    African Journals Online (AJOL)

    Echinodermata: Holothuroidea) with the recognition of two subspecies in Cucumaria frauenfeldi Ludwig. ... Some intraspecific variations in R. frauenfeldi are discussed and, on this basis, the species is rediagnosed and two subspecies recognized.

  3. Spatio-temporal variation in prevalence and intensity of trematodes responsible for waterfowl die-offs in faucet snail-infested waterbodies of Minnesota, USA

    OpenAIRE

    Roy, Charlotte L.; St-Louis, V?ronique

    2017-01-01

    Several non-native trematodes hosted by the invasive Eurasian faucet snail, Bithynia tentaculata, have been causing die-offs of waterfowl in the Midwestern United States and Canada for several decades. Because of the potential implications of these die-offs on waterfowl in non-native settings, it is necessary to better understand the trematodes that cause the die-offs. Here, we studied the spatio-temporal dynamics of two trematodes, Cyathocotyle bushiensis and Sphaeridiotrema spp., known to i...

  4. Xenacoelomorpha's significance for understanding bilaterian evolution

    OpenAIRE

    Hejnol, Andreas; Pang, Kevin

    2016-01-01

    The Xenacoelomorpha, with its phylogenetic position as sister group of the Nephrozoa (Protostomia + Deuterostomia), plays a key-role in understanding the evolution of bilaterian cell types and organ systems. Current studies of the morphological and developmental diversity of this group allow us to trace the evolution of different organ systems within the group and to reconstruct characters of the most recent common ancestor of Xenacoelomorpha. The disparity of the clade shows that there canno...

  5. Molecular cross-talk between sponge host and associated microbes

    Digital Repository Service at National Institute of Oceanography (India)

    Wang, X.; Brandt, D.; Thakur, N.L.; Wiens, M.; Batel, R.; Schroder, H.C.; Muller, W.E.G.

    /endocytose bacteria this process has not been demonstrated on molecular level. In eukaryotic cells clathrin-coated vesicles mediate endocytosis of surface receptors and also extracellular bacteria (Le Borgne and Hoflack, 1998). The formation of these vesicles... also known to promote adhesion in Protostomia and Deuterostomia. Molecules involved in cell-substrate interaction: The dominant molecule present in the extracellular matrix of sponges which functions as a cell-matrix adhesion molecule is collagen...

  6. Spatially-resolved thermoluminescence from snail opercula using an EMCCD

    DEFF Research Database (Denmark)

    Duller, G.A.T.; Kook, Myung Ho; Stirling, R.J.

    2015-01-01

    of almost all B. tentaculata opercula, but it is not known whether the luminescence emitted by the opercula is influenced by these structures. This study uses a newly developed EMCCD imaging system to measure the TL signals from opercula. A combination of microscopic analysis of the opercula using visible...... imagery, and measurement of the TL using the EMCCD system has been undertaken. Variations in TL intensity and equivalent dose (De) are seen, but the two are not correlated. Changes in TL intensity broadly mimic the concentric growth structures, but the largest variations in intensity are between different...

  7. The holothuroid family Rhopalodinidae – its composition ...

    African Journals Online (AJOL)

    The holothuroid family Rhopalodinidae currently contains three genera and 16 species, all restricted in their distribution to the East Atlantic Ocean from Senegal to the ... A key for the identification of the 16 known species is provided. ... Key words: Echinodermata, Holothuroidea, Dactylochirotida, sea cucumbers, taxonomy.

  8. Stomach content analysis of the sea barbel, Galeichthyes jeliceps ...

    African Journals Online (AJOL)

    ing habits of estuarine fish species and their role in the food- web in the ... The contents of each stomach were separated into species or groups, which .... Terrestrial insects. Unidentified larvae and pupae. Mollusca. Gastropoda. Lamellibranchiata. Musculus virgi/iae. Cephalopoda. Echinodermata. Holothuroidea. Tunicata.

  9. Macrofauna associated with the sponge Neopetrosia exigua ...

    African Journals Online (AJOL)

    and Echinodermata (6%, 1 sp.). However, the most dominant species was the polychaete Haplosyllis djibouitensis (Gravier, 1900) representing 71% of total number of specimens collected. The number of species and individuals and the diversity index values were positively, but the evenness index values were negatively ...

  10. Browse Title Index

    African Journals Online (AJOL)

    Vol 26, No 4 (1991), New southern geographical records of intertidal sea urchins (Echinodermata: Echinoidea), with notes on abundance, Abstract PDF. D.J. Marshall, A.N. Hodgson, R.A. Pretorius. Vol 35, No 2 (2000), new species of Heterixalus (Amphibia: Hyperoliidae) from western Madagascar, Abstract. Miguel Vences ...

  11. African Zoology - Vol 26, No 4 (1991)

    African Journals Online (AJOL)

    New southern geographical records of intertidal sea urchins (Echinodermata: Echinoidea), with notes on abundance · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. D.J. Marshall, A.N. Hodgson, R.A. Pretorius, 204-205 ...

  12. Short Note

    African Journals Online (AJOL)

    Clotilde, La Réunion, France. Keywords: Echinodermata, diversity, reef flats, reef slopes, lagoon, Juan de Nova. Abstract — Juan de Nova is one of the scattered islands known as Iles Eparses in the Mozambique Channel (Western Indian Ocean). Historically, they have been isolated from many anthropogenic influences ...

  13. African Zoology - Vol 34, No 3 (1999)

    African Journals Online (AJOL)

    Stolus kilberti, a new species from the east coast of South Africa (Echinodermata: Holothuroidea: Dendrochirotida) with a key to the genus Stolus Selenka · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. V Rajpal, A.S. Thandar, 130-134 ...

  14. African Zoology - Vol 33, No 4 (1998)

    African Journals Online (AJOL)

    Neocucumis kilburni sp. nov. (Echinodermata : Holothuroidea : Cucumariidae) from the east coast of South Africa, with a key to the genus Neocucumis · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Vish Rajpal, Ahmed S. Thandar, 195-199 ...

  15. frauenfeldi Ludwig

    African Journals Online (AJOL)

    Cucumariidae (Echinodermata: Holothuroidea) with the recognition of two subspecies in Cucumaria frauenfeldi Ludwig. A.S. Thandar. Department of Zoology, University of Durban-Westville, Durban. A new genus Roweia in the holothurian family Cucumariidae is erected to accommodate two southem African dendrochi-.

  16. Three-dimensional visualisation of brooding behaviour in two ...

    African Journals Online (AJOL)

    Brooding in ophiuroids (Echinodermata: Ophiuroidea) is a highly-developed reproduction strategy and has evolved independently several times. In South African waters, brooding occurs both in the very small amphiurid Amphipholis squamata, which is hermaphroditic, and in the large ophiodermatid Ophioderma wahlbergii ...

  17. I. Tripneustes gratilla L. (Echinoidea, Echinodermatata)

    African Journals Online (AJOL)

    recruitment of Paracentrotus lividus. (Echinodermata: Echinoidea) in two contrasting habitats. Mar. Ecol. Prog. Ser. 122: 179—191. Maharavo, J. (1993) Etude de l'oursin comestible. Tripneustes gratilla (L. 1758) dans la région de. Nosy-Be (cote nord-ouest de Madagascar):. Densité, morphométrie, nutrition, croissance,.

  18. Author Details

    African Journals Online (AJOL)

    Thandar, Ahmed S. Vol 38, No 2 (2003) - Articles Two new genera and a new species in the holothurian family Cucumariidae (Echinodermata: Holothuroidea) Abstract · Vol 31, No 4 (1996) - Articles Chiridota durbanensis new species and a new record of Neothyonidium arthroprocessum from the east coast of South Africa ...

  19. Benthos off Cochin, Southwest coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Harkantra, S.N.; Parulekar, A.H.

    Macro-invertebrate benthic fauna off Cochin mainly composed of polychaeta (82.45%), crustacea (7.62%), mollusca (5.92%), sipuncula (2.25%), nemertinea (0.96%) and echinodermata (0.80%). The maximum population density and biomass values were 304 plus...

  20. Effects of sediment organic matter quality on bioaccumulation, degradation, and distribution of pyrene in two macrofaunal species and their surrounding sediment

    DEFF Research Database (Denmark)

    Granberg, Maria E.; Selck, Henriette

    2007-01-01

    of sediment-associated pyrene in Nereis diversicolor (Annelida) and Amphiura filiformis (Echinodermata), as well as the combined effect of SOM quality and infaunal bioturbation on pyrene distribution and metabolism in the sediment. After 45 d of exposure, SOM quality almost doubled pyrene bioaccumulation...

  1. Local habitat drivers of macrobenthos in the northern, central and ...

    African Journals Online (AJOL)

    Annelida, Arthropoda, Mollusca, Echinodermata, Sipuncula and Cnidaria (>50 taxa each) were the dominant macrobenthic groups in the bight. Annelida were dominated by the polychaete families Spionidae, Terrebelidae and Cirratullidae, which were generally associated with outwelling and a mud depocentre off the ...

  2. Browse Title Index

    African Journals Online (AJOL)

    Items 726 - 750 of 1840 ... ... No 2 (1996), Feeding, tentacle and gut morphology in five species of southern African intertidal holothuroids (Echinodermata), Abstract PDF. Greg G. Foster, Alan N. Hodgson. Vol 30, No 4 (1995), Female guppies use orange as choice cue: a manipulative test, Abstract PDF. R Brooks, N Caithness.

  3. New data on Late Turonian crinoids from the Bohemian Cretaceous Basin, Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Žítt, Jiří; Vodrážka, R.

    2008-01-01

    Roč. 83, č. 3 (2008), s. 311-326 ISSN 1214-1119 R&D Projects: GA ČR(CZ) GA205/06/0842 Institutional research plan: CEZ:AV0Z30130516 Keywords : Echinodermata * Crinoidea * taxonomy * taphonomy * Late Turonian * Bohemian Cretaceous Basin Subject RIV: DB - Geology ; Mineralogy

  4. List of scientific publications by Professor Dr. H. Engel

    NARCIS (Netherlands)

    Veen, van der Bauke

    1968-01-01

    From the following bibliography, most of the publications directed to the general public, such as articles in newspapers, etc., as well as part of the book-reviews, have been omitted. The topics are divided over six headings: Hirudinea, Echinodermata, Opisthobranchia, History of Biology, Museology,

  5. First-year survival of North East Atlantic mackerel (Scomber scombrus) from 1998 to 2012 appears to be driven by availability of Calanus, a preferred copepod prey

    DEFF Research Database (Denmark)

    Jansen, Teunis

    2016-01-01

    ., Branchiopoda spp. and Echinodermata spp. larvae), as well as stock size, temperature and wind-induced turbulence were not found to be significant. However, stock size was retained in the final model because of a significant interaction with Calanus in oceanic areas west of the North European continental shelf...

  6. [Infection rates of mollusks and fishes with the larval stages of Trematoda of the family Opisthorchidae in the Yaroslavl Region].

    Science.gov (United States)

    Molodozhnikova, N M

    2006-01-01

    The paper presents the results of a study of the infection rates of mollusks of the family Bythiniidae (Bithynia tentaculata, Opisthorchophorus troscheli) and fishes with the larval stages of Opisthorchidae in different districts of the Yaroslavl Region. A total of 3,708 mollusks from the water reservoirs of different types (small rivers, lakes, ponds, and canals) were examined in the Nekouzsky, Yaroslavsky, and Pereslavsky Districts of the Yaroslavl Region in 1989 to 1999. Opisthorchis cercarias were found in 7 of the 10 studied water reservoirs. The total rate of infection of mollusks with all types with Trematoda partenitas and cercarias in different water reservoirs averaged 18.5 +/- 3.5% for Bithynia tentaculata and 19.1 +/- 4.1% for Opisthorchophorus troscheli. Trematoda metacercarias of the family Opisthorchidae were revealed in roaches, ides, verkhovkas, silver breams, and chubs in four different water reservoirs (small rivers and a lake) of the region. Pseudamphistomum truncates, Opisthorchis felineus, and Metorchis xanthosomus were present among the metacercarias found. It is concluded that there may be sporadic cases of Opisthorchis infection in wild and domestic animals and humans in the Yaroslavl Region.

  7. Inter- and intra-specific variability in δ13C and δ18O values of freshwater gastropod shells from Lake Lednica, western Poland

    Science.gov (United States)

    Apolinarska, Karina; Pełechaty, Mariusz

    2017-09-01

    This study focuses on the inter- and intra-specific variability in δ13C and δ18O values of shells and opercula of gastropods sampled live from the littoral zone of Lake Lednica, western Poland. The δ13C and δ18O values were measured in individual opercula of Bithynia tentaculata and in shells of Bithynia tentaculata, Gyraulus albus, Gyraulus crista, Lymnaea sp., Physa fontinalis, Radix auricularia, Theodoxus fluviatilis and Valvata cristata. The gastropods selected for the study are among the species most commonly found in European Quaternary lacustrine sediments. The carbon isotope composition of the gastropod shells was species-specific and the same order of species from the most to the least 13C-depleted was observed at all sites sampled. Differences in shell δ13C values between species were similar at all sampling sites, thus the factors influencing shell isotopic composition were interpreted as species-specific. The δ18O values of shells were similar in all the species investigated. Significant intra-specific variability in shell δ13C and δ18O values was observed not only within the populations of Lake Lednica, which can be explained by heterogeneity of δ13C DIC, δ18O water and water temperature between the sites where macrophytes with snails attached were sampled, but also between individuals sampled from restricted areas of the lake's bottom. The latter points to the importance of factors related to the ontogeny of individual gastropods.

  8. Nematode parasites of marsupials and small rodents from the Brazilian Atlantic Forest in the State of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Delir Corrêa Gomes

    2003-12-01

    Full Text Available Nematodes from opossums and rodents captured in the Brazilian Atlantic Forest in the State of Rio de Janeiro, Brazil were studied. From the opossums Didelphis aurita Weid-Neuweid, 1826 and Philander opossum (Linnaeus, 1758 the following nematode species were recovered: Viannaia hamata Travassos, 1914, Aspidodera raillieti Travassos, 1913, Cruzia tentaculata (Rudolphi, 1819, Travassos, 1917, Turgida turgida (Rudolphi, 1819 Travassos, 1919, Gongylonemoides marsupialis (Vaz & Pereira, 1934 Freitas & Lent, 1937, Viannaia viannai Travassos, 1914, Spirura guianensis (Ortlepp, 1924 Chitwood, 1938 and from the rodents Akodon cursor (Winger, 1887, Nectomys squamipes (Brants, 1827, Oligoryzomys eliurus (Wagner, 1845 and Oryzomys intermedius (Leche, 1886: Hassalstrongylus epsilon (Travassos, 1937 Durette-Desset, 1971, Syphacia obvelata (Rudolphi, 1802 Seurat, 1916, S. venteli Travassos, 1937, Physaloptera bispiculata Vaz & Pereira, 1935, Litomosoides carinii (Travassos, 1919 Vaz, 1934, Viannaia viannai, Hassalstrongylus epsilon, H. zeta (Travassos, 1937 Durette-Desset, 1971, Stilestrongylus aculeata (Travassos, 1918 Durette-Desset, 1971 S. eta (Travassos, 1937 Durette-Desset, 1971. Highest worm burdens and prevalences were those related to Cruzia tentaculata in marsupials. Stilestrongylus aculeata was referred for the first time in Akodon cursor.

  9. Biological activities and biomedical potential of sea cucumber (Stichopus japonicus: a review

    Directory of Open Access Journals (Sweden)

    Gun-Woo Oh

    2017-11-01

    Full Text Available Abstract Members of the phylum Echinodermata, commonly known as echinoderms, are exclusively marine invertebrates. Among the Echinodermata, sea cucumber belongs to the family Holothuroidea. The sea cucumber Stichopus (Apostichous japonicus (Selenka is an invertebrate animal inhabiting the coastal sea around Korean, Japan, China, and Russia. Sea cucumber has a significant commercial value, because it contains valuable nutrients such as vitamins and minerals. They possess a number of distinctive biologically and pharmacologically important compounds. In particular, the body wall of sea cucumber is a major edible part. It consists of peptide, collagen, gelatin, polysaccharide, and saponin, which possess several biological activities such as anti-cancer, anti-coagulation, anti-oxidation, and anti-osteoclastogenesis. Furthermore, the regenerative capacity of sea cucumber makes it a medically important organism. This review presents the various biological activities and biomedical potential of sea cucumber S. japonicus.

  10. DNA primers for amplification of mitochondrial cytochrome c oxidase subunit I from diverse metazoan invertebrates.

    Science.gov (United States)

    Folmer, O; Black, M; Hoeh, W; Lutz, R; Vrijenhoek, R

    1994-10-01

    We describe "universal" DNA primers for polymerase chain reaction (PCR) amplification of a 710-bp fragment of the mitochondrial cytochrome c oxidase subunit I gene (COI) from 11 invertebrate phyla: Echinodermata, Mollusca, Annelida, Pogonophora, Arthropoda, Nemertinea, Echiura, Sipuncula, Platyhelminthes, Tardigrada, and Coelenterata, as well as the putative phylum Vestimentifera. Preliminary comparisons revealed that these COI primers generate informative sequences for phylogenetic analyses at the species and higher taxonomic levels.

  11. A new Devonian asteroid-like ophiuroid from Spain

    OpenAIRE

    Blake, D. B.; Zamora, S.; García-Alcalde, J. L.

    2015-01-01

    A new Lochkovian (early Devonian) ophiuroid (Echinodermata), Ophiohispania elegans n. gen. and sp., is described based on the dorsal surface and a ventral? arm fragment of a single small, well-preserved specimen from Asturias (northwest Spain). Although readily assigned to the ophiuran family Encrinasteridae, arrangement of the robust primary ambulacral column and ambital framework ossicles of O. elegans is superficially similar to approximately coeval members of the asteroid family Xenasteri...

  12. Echinoderms; potential model systems for studies on muscle regeneration

    OpenAIRE

    García-Arrarás, José E.; Dolmatov, Igor Yu.

    2010-01-01

    Organisms of the phylum Echinodermata show some of the most impressive regenerative feats within the animal kingdom. Following injury or self-induced autotomy, species in this phylum can regenerate most tissues and organs, being the regeneration of the muscular systems one of the best studied. Even though echinoderms are closely related to chordates, they are little known in the biomedical field, and therefore their uses to study pharmacological effects on muscle formation and/or regeneration...

  13. Assessment System for Aircraft Noise (ASAN) Citation Database. Volume 2

    Science.gov (United States)

    1989-12-01

    Arachnida 01.02.10.02.00.00 Aramidae 01.02.08.03.01.01 *Arctic peregrine falcon 01.01.12.01.01.00 Arctocephalus 01.01.12.01.01.01 *Arctocephalus townsendi...Orconectes shoupi 04.03.o0.00.00.00 . Arachnida " Scorpions " Spiders 05.00000000.00 Echinodermata Echinoderms Sea-Cucumbers Sea-Urchins Starfishes Endangered or Threatened Species Are Identified with an Asterisk

  14. Survey of biosystematic and sexual reproductive physiology in Holothuroidea on Hormozgan Province

    OpenAIRE

    Tehrani Frad, Akram

    2006-01-01

    Sea cucumbers belong to phylum Echinodermata, order Holothuroidea are an abundant and diverse group of Invertebrates, with over 1400 species occuring from the intertidal to the deepest oceanic trenches. Sea cucumbers are important components of the food chain in temperate and coral reef ecosystems and they play an important role as deposite feeders and suspension feeders. Rapid decline in populations may have serious consequences for the survival of other species that are part of the same com...

  15. Characterization of O-GlcNAcylation in starfish (Asterina pectinifera) development from fertilization to bipinnaria larva.

    Science.gov (United States)

    Ogawa, Mitsutaka; Adachi, Tatsuhiro; Ikegami, Susumu; Kato, Koichi H; Yamamoto, Akitsugu; Kamemura, Kazuo

    2011-01-01

    Though O-linked β-N-acetylglucosaminylation (O-GlcNAcylation) of nucleocytoplasmic proteins has been found in many multicellular organisms, its presence or absence in Echinodermata is unknown. Here we report the occurrence of O-GlcNAcylation in starfish (Asterina pectinifera) oocytes and the apparent O-GlcNAcylation pattern in starfish early development. O-GlcNAcylation might participate in the regulation of starfish development at the mid-blastula stage and thereafter.

  16. Doplněk k poznání vodních měkkýšů Labe mezi Hřenskem a Střekovem a srovnání s malakofaunou Labe v jiných úsecích

    Directory of Open Access Journals (Sweden)

    Luboš Beran

    2009-11-01

    Full Text Available This paper completes knowledge on aquatic molluscs of the free flowing part of the Elbe River between Hřensko and the weir with lock in Ústí nad Labem – Střekov. Altogether, 21 species of aquatic molluscs (9 gastropods, 12 bivalves were found in 2009. Viviparus viviparus, Potamopyrgus antipodarum, Bithynia tentaculata, Ancylus fluviatilis, Unio pictorum, Anodonta anatina, Corbicula fluminea, Sphaerium corneum and Pisidium supinum were the most frequently occurring molluscs found during this research. The occurrence of two endangered bivalves Pseudanodonta complanata and Pisidium moitessierianum was recorded. No significant difference from the previous author’s research was found. Molluscan communities of this part of the river were compared with those of the upper canalized part of the Elbe River which contain more species (especially gastropods living predominantly in stagnant or slowly flowing waters e. g. Stagnicola palustris, S. corvus, Lymnaea stagnalis, Planorbis planorbis, Bathyomphalus contortus, Anisus vortex, Hippeutis complanatus, Ferrissia fragilis.

  17. Spatio-temporal variation in prevalence and intensity of trematodes responsible for waterfowl die-offs in faucet snail-infested waterbodies of Minnesota, USA.

    Science.gov (United States)

    Roy, Charlotte L; St-Louis, Véronique

    2017-12-01

    Several non-native trematodes hosted by the invasive Eurasian faucet snail, Bithynia tentaculata, have been causing die-offs of waterfowl in the Midwestern United States and Canada for several decades. Because of the potential implications of these die-offs on waterfowl in non-native settings, it is necessary to better understand the trematodes that cause the die-offs. Here, we studied the spatio-temporal dynamics of two trematodes, Cyathocotyle bushiensis and Sphaeridiotrema spp., known to infect waterfowl in northern Minnesota, USA, via their intermediate host, the faucet snail (Bithynia tentaculata). We studied prevalence (% of snails infected within a sample) and intensity (mean number of parasites per infected snail within a sample) of faucet snail infection with these two trematodes in small lakes, large lakes, ponds, and rivers in northern Minnesota in the spring, summer, and fall of 2011-2013. We tested whether parasite prevalence and infection intensity could be explained spatially (as a function of the abundance of faucet snails, average snail size, water depth, and proximity to known waterfowl groups) and temporally (across years and seasons) using generalized estimating equation models. The spatial and temporal patterns we observed varied within and among waterbodies. For both parasite species, parasite prevalence and intensity of infection were consistently higher in samples with larger snails and in deeper portions of the waterbodies. In Lake Winnibigoshish, prevalence was lower farther from the large waterfowl groups we observed, but the abundance of snails in a sample had no effect on prevalence or intensity of infection. Our findings help improve understanding of this multi-species system, but also illustrate the complexity of modeling the spatial and temporal dynamics of infections in waterbodies that are so variable in size, shape, waterfowl use, and function.

  18. Evolution of highly diverse forms of behavior in molluscs.

    Science.gov (United States)

    Hochner, Binyamin; Glanzman, David L

    2016-10-24

    Members of the phylum Mollusca demonstrate the animal kingdom's tremendous diversity of body morphology, size and complexity of the nervous system, as well as diversity of behavioral repertoires, ranging from very simple to highly flexible. Molluscs include Solenogastres, with their worm-like bodies and behavior (see phylogenetic tree; Figure 1); Bivalvia (mussels and clams), protected by shells and practically immobile; and the cephalopods, such as the octopus, cuttlefish and squid. The latter are strange-looking animals with nervous systems comprising up to half a billion neurons, which mediate the complex behaviors that characterize these freely moving, highly visual predators. Molluscs are undoubtedly special - their extraordinary evolutionary advance somehow managed to sidestep the acquisition of the rigid skeleton that appears essential to the evolution of other 'successful' phyla: the exoskeleton in ecdysozoan invertebrates and the internal skeleton in Deuterostomia, including vertebrates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Xenacoelomorpha's significance for understanding bilaterian evolution.

    Science.gov (United States)

    Hejnol, Andreas; Pang, Kevin

    2016-08-01

    The Xenacoelomorpha, with its phylogenetic position as sister group of the Nephrozoa (Protostomia+Deuterostomia), plays a key-role in understanding the evolution of bilaterian cell types and organ systems. Current studies of the morphological and developmental diversity of this group allow us to trace the evolution of different organ systems within the group and to reconstruct characters of the most recent common ancestor of Xenacoelomorpha. The disparity of the clade shows that there cannot be a single xenacoelomorph 'model' species and strategic sampling is essential for understanding the evolution of major traits. With this strategy, fundamental insights into the evolution of molecular mechanisms and their role in shaping animal organ systems can be expected in the near future. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. The development of the larval nervous system, musculature and ciliary bands of Pomatoceros lamarckii (Annelida: heterochrony in polychaetes

    Directory of Open Access Journals (Sweden)

    Shimeld Sebastian M

    2006-10-01

    Full Text Available Abstract Background To understand the evolution of animals it is essential to have taxon sampling across a representative spread of the animal kingdom. With the recent rearrangement of most of the Bilateria into three major clades (Ecdysozoa, Lophotrochozoa and Deuterostomia it has become clear that the Lophotrochozoa are relatively poorly represented in our knowledge of animal development, compared to the Ecdysozoa and Deuterostomia. We aim to contribute towards redressing this balance with data on the development of the muscular, nervous and ciliary systems of the annelid Pomatoceros lamarckii (Serpulidae. We compare our data with other lophotrochozoans. Results P. lamarckii develops locomotory and feeding structures that enable it to become a swimming, planktotrophic larva within 24 hours. Formation of the trochophore includes development of a prototroch, metatroch and neurotroch, development of apical and posterior nervous elements at similar times, and development of musculature around the ciliary bands and digestive tract prior to development of any body wall muscles. The adult nervous and muscular systems are essentially preformed in the late larva. Interestingly, the muscular systems of the larvae and juvenile worms do not include the circular muscles of the body wall, which are considered to be plesiomorphic for annelids, although the possibility that circular muscles develop after these stages cannot be ruled out at this point. Conclusion A comparison between polychaetes shows variability in the timing (heterochrony of development of body wall muscles and elements of the nervous system. These heterochronies are one route for evolution of different life history strategies, such as adaptations to feeding requirements.

  1. Preliminary Study on Coral Reef and Its Associated Biota in Qatari Waters, Arabian Gulf

    OpenAIRE

    Al Ansi, Mohsin A. [محسن عبد الله العنسي; Al-Khayat, Jassim A.

    1999-01-01

    Coral reef grounds and their associated biota m Qatari waters were investigated by Scuba diving. Four selected reef-sites were studied. Coral was presented by 17 species. Descriptive notes of each site and an initial list of associated fauna and flora were presented. The associated biota composed mainly of Algae 23 sp, Porifera 5 sp, Bryozoa 4 sp, Polychaeta 17 sp, Echinodermata 21 sp, Mollusca 102 sp, Chordata 4 sp, and Crustacea 15 sp. Mollusca was the predominant group in all visited sites...

  2. Structure and dynamics of the biota associated with Macrocystis pyrifera (Phaeophyta from the Beagle Channel, Tierra del Fuego

    Directory of Open Access Journals (Sweden)

    Mariana L. Adami

    1999-12-01

    Full Text Available The community associated to the kelp Macrocystis pyrifera from the Beagle Channel (54°00´S; 68°20´W was studied. Sixty-eight taxa including Algae (5, Porifera (indet., Bryozoa (7, Nemertea (2, Annelida (10, Mollusca (22, Crustacea (15 and Echinodermata (7 were recognized. A seasonal sampling during one year showed differences in taxa composition when comparing (a two different environments; (b the spring-summer period and the autumn-winter period; and (c the parts of the alga (fronds and holdfast.

  3. Taxonomy Icon Data: purple urchin [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available purple urchin Strongylocentrotus purpuratus Echinodermata Strongylocentrotus_purpuratus_L.png Strongylocentr...otus_purpuratus_NL.png Strongylocentrotus_purpuratus_S.png Strongylocentrotus_purpu...ratus_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Strongylocentrotus+purpuratus&t=L http://biosc...iencedbc.jp/taxonomy_icon/icon.cgi?i=Strongylocentrotus+purpuratus&t=NL http://bi...osciencedbc.jp/taxonomy_icon/icon.cgi?i=Strongylocentrotus+purpuratus&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Strongylocentrotus+purpuratus&t=NS ...

  4. Structural analysis of the α subunit of Na(+)/K(+) ATPase genes in invertebrates.

    Science.gov (United States)

    Thabet, Rahma; Rouault, J-D; Ayadi, Habib; Leignel, Vincent

    2016-01-01

    The Na(+)/K(+) ATPase is a ubiquitous pump coordinating the transport of Na(+) and K(+) across the membrane of cells and its role is fundamental to cellular functions. It is heteromer in eukaryotes including two or three subunits (α, β and γ which is specific to the vertebrates). The catalytic functions of the enzyme have been attributed to the α subunit. Several complete α protein sequences are available, but only few gene structures were characterized. We identified the genomic sequences coding the α-subunit of the Na(+)/K(+) ATPase, from the whole-genome shotgun contigs (WGS), NCBI Genomes (chromosome), Genomic Survey Sequences (GSS) and High Throughput Genomic Sequences (HTGS) databases across distinct phyla. One copy of the α subunit gene was found in Annelida, Arthropoda, Cnidaria, Echinodermata, Hemichordata, Mollusca, Placozoa, Porifera, Platyhelminthes, Urochordata, but the nematodes seem to possess 2 to 4 copies. The number of introns varied from 0 (Platyhelminthes) to 26 (Porifera); and their localization and length are also highly variable. Molecular phylogenies (Maximum Likelihood and Maximum Parsimony methods) showed some clusters constituted by (Chordata/(Echinodermata/Hemichordata)) or (Plathelminthes/(Annelida/Mollusca)) and a basal position for Porifera. These structural analyses increase our knowledge about the evolutionary events of the α subunit genes in the invertebrates. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. New evidence of Holocene atmospheric circulation dynamics based on lake sediments from southern Sweden: a link to the Siberian High

    Science.gov (United States)

    Muschitiello, F.; Schwark, L.; Wohlfarth, B.; Sturm, C.; Hammarlund, D.

    2013-10-01

    Oxygen (δ18O) and carbon (δ13C) isotope records of calcitic carbonate components (Chara sp. algal encrustations and Bithynia tentaculata gastropod opercula) from a lake-sediment succession on the Baltic Sea island of Gotland, south-eastern Sweden, have been obtained to investigate regional climate dynamics during the Holocene. The hydrological sensitivity of the small lake, particularly in terms of spring snowmelt contribution to the local water budget, provides a means of tracing past changes in the influence of snow-bearing easterly winds across the Baltic Sea Proper, which signifies the wintertime strength of the Siberian High. Repeated episodic depletions in 18O at the centennial scale correlate with events of increased potassium concentration in the GISP2 ice-core record from Greenland, which indicates a coupling to large-scale fluctuations in atmospheric circulation patterns. A corresponding correlation with simultaneous depletions in 13C suggests repeated responses of the local lake hydrology to snow-rich winters through decreasing water residence time, perhaps augmented by methanogenesis due to prolonged ice-cover seasons under the influence of an expanding Siberian High. Frequency analysis of the isotopic records reveals well-defined fluctuations at quasi-500-520-, 670-, 830- and 1430-yr periodicities, and a gradually stronger impact of Polar air outbreaks across the southern Baltic Sea region with time after ca 6000 cal. BP.

  6. Recolonization of macrofauna in unpolluted sands placed in a polluted yachting harbour: A field approach using experimental trays

    Science.gov (United States)

    Guerra-García, J. M.; García-Gómez, J. C.

    2009-01-01

    A field experiment using trays was conducted at Ceuta's yachting harbour, North Africa, to study the effect in recolonization of placing trays with unpolluted defaunate sediments (fine and gross sands with low contents of organic matter) inside an enclosed yachting harbour characterized by high percentages of silt and clay and high concentrations of organic matter. Sediment recolonization in the trays was mainly undertaken by the species living naturally at the yachting harbour, which recolonized both uncontaminated gross and fine sand trays (such as the crustaceans Corophium runcicorne, Corophium sextonae and Nebalia bipes, the mollusc Parvicardium exiguum and the polychaete Pseudomalacoceros tridentata). However, other species like the polychaetes Cirriformia tentaculata and Platynereis dumerilii, although also abundant in the yachting harbour, were unable to colonize the trays through transport of larvae and/or adults in the water column. The recolonization was very quick, and after the first month, the values of abundance, species richness, diversity and evenness were similar in the experimental trays and in the reference area (yachting harbour). Although the multivariate analysis showed that the species composition differed between the trays and the reference area, there were no significant differences in recolonization of gross and fine sands, indicating that other factors different from the granulometry are modulating the recolonization patterns.

  7. Helminths of three species of opossums (Mammalia, Didelphidae from Mexico

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    Karla Acosta-Virgen

    2015-07-01

    Full Text Available From August 2011 to November 2013, 68 opossums (8 Didelphis sp., 40 Didelphis virginiana, 15 Didelphis marsupialis, and 5 Philander opossum were collected in 18 localities from 12 Mexican states. A total of 12,188 helminths representing 21 taxa were identified (6 trematodes, 2 cestodes, 3 acanthocephalans and 10 nematodes. Sixty-six new locality records, 9 new host records, and one species, the trematode Brachylaima didelphus, is added to the composition of the helminth fauna of the opossums in Mexico. These data, in conjunction with previous records, bring the number of taxa parasitizing the Mexican terrestrial marsupials to 41. Among these species, we recognized a group of helminths typical of didelphids in other parts of the Americas. This group is constituted by the trematode Rhopalias coronatus, the acanthocephalan Oligacanthorhynchus microcephalus and the nematodes Cruzia tentaculata, Gnathostoma turgidum, and Turgida turgida. In general, the helminth fauna of each didelphid species showed a stable taxonomic composition with respect to previously sampled sites. This situation suggests that the rate of accumulation of helminth species in the inventory of these 3 species of terrestrial marsupials in the Neotropical portion of Mexico is decreasing; however, new samplings in the Nearctic portion of this country will probably increase the richness of the helminthological inventory of this group of mammals.

  8. Survival of the faucet snail after chemical disinfection, pH extremes, and heated water bath treatments

    Science.gov (United States)

    Mitchell, A.J.; Cole, Rebecca A.

    2008-01-01

    The faucet snail Bithynia tentaculata, a nonindigenous aquatic snail from Eurasia, was introduced into Lake Michigan in 1871 and has spread to the mid-Atlantic states, the Great Lakes region, Montana, and most recently, the Mississippi River. The faucet snail serves as intermediate host for several trematodes that have caused large-scale mortality among water birds, primarily in the Great Lakes region and Montana. It is important to limit the spread of the faucet snail; small fisheries equipment can serve as a method of snail distribution. Treatments with chemical disinfection, pH extremes, and heated water baths were tested to determine their effectiveness as a disinfectant for small fisheries equipment. Two treatments eliminated all test snails: (1) a 24-h exposure to Hydrothol 191 at a concentration of at least 20 mg/L and (2) a treatment with 50°C heated water for 1 min or longer. Faucet snails were highly resistant to ethanol, NaCl, formalin, Lysol, potassium permanganate, copper sulfate, Baquacil, Virkon, household bleach, and pH extremes (as low as 1 and as high as 13).

  9. Helminths of three species of opossums (Mammalia, Didelphidae) from Mexico

    Science.gov (United States)

    Acosta-Virgen, Karla; López-Caballero, Jorge; García-Prieto, Luis; Mata-López, Rosario

    2015-01-01

    Abstract From August 2011 to November 2013, 68 opossums (8 Didelphis sp., 40 Didelphis virginiana, 15 Didelphis marsupialis, and 5 Philander opossum) were collected in 18 localities from 12 Mexican states. A total of 12,188 helminths representing 21 taxa were identified (6 trematodes, 2 cestodes, 3 acanthocephalans and 10 nematodes). Sixty-six new locality records, 9 new host records, and one species, the trematode Brachylaima didelphus, is added to the composition of the helminth fauna of the opossums in Mexico. These data, in conjunction with previous records, bring the number of taxa parasitizing the Mexican terrestrial marsupials to 41. Among these species, we recognized a group of helminths typical of didelphids in other parts of the Americas. This group is constituted by the trematode Rhopalias coronatus, the acanthocephalan Oligacanthorhynchus microcephalus and the nematodes Cruzia tentaculata, Gnathostoma turgidum, and Turgida turgida. In general, the helminth fauna of each didelphid species showed a stable taxonomic composition with respect to previously sampled sites. This situation suggests that the rate of accumulation of helminth species in the inventory of these 3 species of terrestrial marsupials in the Neotropical portion of Mexico is decreasing; however, new samplings in the Nearctic portion of this country will probably increase the richness of the helminthological inventory of this group of mammals. PMID:26257556

  10. Vodní měkkýši Labe mezi Pardubicemi a Hřenskem

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    Luboš Beran

    2005-05-01

    Full Text Available Aquatic molluscs of the Elbe River between Němčice (near Pardubice, Eastern Bohemia, Czech Republic and Hřensko (Northern Bohemia, Czech Republic at 27 localities were investigated from 1994 to 2004. Altogether 40 species (24 gastropods, 16 bivalves from 77 species known on the territory of the Czech Republic were found at sites under study. A gradual invasion of 6 non-native species (Potamopyrgus antipodarum, Physella acuta, Menetus dilatatus, Ferrissia clessiniana, Corbicula fluminea and an extinction of another species (Theodoxus fluviatilis, Planorbis carinatus, Unio crassus, Pisidium amnicum were documented in comparison with historical records. Rare mussel Pseudanodonta complanata and rare pea mussel Pisidium moitessierianum were found at several localities under study and these finds document survival of these bivalves in the Elbe River. Molluscan communities of particular localities were most often usually compounded from species Viviparus viviparus (downstream of loc. 9, Bithynia tentaculata, Radix auricularia, Radix ampla, Unio pictorum, Anodonta anatina, Corbicula fluminea (downstream of loc. 8, Sphaerium rivicola (downstream of loc. 7, Sphaerium corneum s. lat., Pisidium supinum, Dreissena polymorpha.

  11. Endoparásitos de micromamíferos del noroeste de Perú. 1: helmintos de marsupiales

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    Manuel Tantaleán

    2011-05-01

    Full Text Available En este trabajo, informamos los resultados del análisis parasitológico realizado a 40 individuos marsupiales de las especies Caluromys lanatus, Didelphis marsupialis, Marmosops noctivagus, Metachirus nudicaudatus, Marmosa (Micoureus regina, Monodelphis adusta, Philander andersoni y Philander opossum procedentes del departamento de Loreto, Perú. Se determinaron en total 11 especies de helmintos parásitos: Nematoda: Aspidodera sp., Cruzia tentaculata, Physaloptera mirandai, Physaloptera sp., Pterygodermatites sp., Trichuris sp., Turgida turgida, y Viannaia sp.; Trematoda: Podospathalium pedatum; Acanthocephala: Giganthorhynchus ortizi; y Pentastomida: ninfa. Los parásitos Trichuris sp., Pterygodematities sp., Turgida turgida, Viannaia sp. y Podospathalium pedatum son nuevos registros para el Perú. De igual manera, se registran por primera vez las siguientes asociaciones parásitos-huéspedes: Pterygodermatites sp.-Marmosa regina, Viannaia sp.- Marmosops noctivagus, Trichuris sp.-Marmosops cf. noctivagus, Podospathalium pedatum-Monodelphis adusta, Giganthorhynchus ortizi-Marmosops cf. noctivagus, y ninfas de pentastómidos-Marmosa regina y Metachirus nudicaudatus.

  12. Mesodermal gene expression in the acoel Isodiametra pulchra indicates a low number of mesodermal cell types and the endomesodermal origin of the gonads.

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    Marta Chiodin

    Full Text Available Acoelomorphs are bilaterally symmetric small marine worms that lack a coelom and possess a digestive system with a single opening. Two alternative phylogenetic positions of this group within the animal tree are currently debated. In one view, Acoelomorpha is the sister group to all remaining Bilateria and as such, is a morphologically simple stepping stone in bilaterian evolution. In the other, the group is a lineage within the Deuterostomia, and therefore, has derived a simple morphology from a more complex ancestor. Acoels and the closely related Nemertodermatida and Xenoturbellida, which together form the Acoelomorpha, possess a very limited number of cell types. To further investigate the diversity and origin of mesodermal cell types we describe the expression pattern of 12 orthologs of bilaterian mesodermal markers including Six1/2, Twist, FoxC, GATA4/5/6, in the acoel Isodiametra pulchra. All the genes are expressed in stem cells (neoblasts, gonads, and at least subsets of the acoel musculature. Most are expressed in endomesodermal compartments of I. pulchra developing embryos similar to what has been described in cnidarians. Our molecular evidence indicates a very limited number of mesodermal cell types and suggests an endomesodermal origin of the gonads and the stem cell system. We discuss our results in light of the two prevailing phylogenetic positions of Acoelomorpha.

  13. Mesodermal Gene Expression in the Acoel Isodiametra pulchra Indicates a Low Number of Mesodermal Cell Types and the Endomesodermal Origin of the Gonads

    Science.gov (United States)

    Chiodin, Marta; Børve, Aina; Berezikov, Eugene; Ladurner, Peter; Martinez, Pedro; Hejnol, Andreas

    2013-01-01

    Acoelomorphs are bilaterally symmetric small marine worms that lack a coelom and possess a digestive system with a single opening. Two alternative phylogenetic positions of this group within the animal tree are currently debated. In one view, Acoelomorpha is the sister group to all remaining Bilateria and as such, is a morphologically simple stepping stone in bilaterian evolution. In the other, the group is a lineage within the Deuterostomia, and therefore, has derived a simple morphology from a more complex ancestor. Acoels and the closely related Nemertodermatida and Xenoturbellida, which together form the Acoelomorpha, possess a very limited number of cell types. To further investigate the diversity and origin of mesodermal cell types we describe the expression pattern of 12 orthologs of bilaterian mesodermal markers including Six1/2, Twist, FoxC, GATA4/5/6, in the acoel Isodiametra pulchra. All the genes are expressed in stem cells (neoblasts), gonads, and at least subsets of the acoel musculature. Most are expressed in endomesodermal compartments of I. pulchra developing embryos similar to what has been described in cnidarians. Our molecular evidence indicates a very limited number of mesodermal cell types and suggests an endomesodermal origin of the gonads and the stem cell system. We discuss our results in light of the two prevailing phylogenetic positions of Acoelomorpha. PMID:23405161

  14. Mesodermal gene expression in the acoel Isodiametra pulchra indicates a low number of mesodermal cell types and the endomesodermal origin of the gonads.

    Science.gov (United States)

    Chiodin, Marta; Børve, Aina; Berezikov, Eugene; Ladurner, Peter; Martinez, Pedro; Hejnol, Andreas

    2013-01-01

    Acoelomorphs are bilaterally symmetric small marine worms that lack a coelom and possess a digestive system with a single opening. Two alternative phylogenetic positions of this group within the animal tree are currently debated. In one view, Acoelomorpha is the sister group to all remaining Bilateria and as such, is a morphologically simple stepping stone in bilaterian evolution. In the other, the group is a lineage within the Deuterostomia, and therefore, has derived a simple morphology from a more complex ancestor. Acoels and the closely related Nemertodermatida and Xenoturbellida, which together form the Acoelomorpha, possess a very limited number of cell types. To further investigate the diversity and origin of mesodermal cell types we describe the expression pattern of 12 orthologs of bilaterian mesodermal markers including Six1/2, Twist, FoxC, GATA4/5/6, in the acoel Isodiametra pulchra. All the genes are expressed in stem cells (neoblasts), gonads, and at least subsets of the acoel musculature. Most are expressed in endomesodermal compartments of I. pulchra developing embryos similar to what has been described in cnidarians. Our molecular evidence indicates a very limited number of mesodermal cell types and suggests an endomesodermal origin of the gonads and the stem cell system. We discuss our results in light of the two prevailing phylogenetic positions of Acoelomorpha.

  15. Xenacoelomorpha is the sister group to Nephrozoa.

    Science.gov (United States)

    Cannon, Johanna Taylor; Vellutini, Bruno Cossermelli; Smith, Julian; Ronquist, Fredrik; Jondelius, Ulf; Hejnol, Andreas

    2016-02-04

    The position of Xenacoelomorpha in the tree of life remains a major unresolved question in the study of deep animal relationships. Xenacoelomorpha, comprising Acoela, Nemertodermatida, and Xenoturbella, are bilaterally symmetrical marine worms that lack several features common to most other bilaterians, for example an anus, nephridia, and a circulatory system. Two conflicting hypotheses are under debate: Xenacoelomorpha is the sister group to all remaining Bilateria (= Nephrozoa, namely protostomes and deuterostomes) or is a clade inside Deuterostomia. Thus, determining the phylogenetic position of this clade is pivotal for understanding the early evolution of bilaterian features, or as a case of drastic secondary loss of complexity. Here we show robust phylogenomic support for Xenacoelomorpha as the sister taxon of Nephrozoa. Our phylogenetic analyses, based on 11 novel xenacoelomorph transcriptomes and using different models of evolution under maximum likelihood and Bayesian inference analyses, strongly corroborate this result. Rigorous testing of 25 experimental data sets designed to exclude data partitions and taxa potentially prone to reconstruction biases indicates that long-branch attraction, saturation, and missing data do not influence these results. The sister group relationship between Nephrozoa and Xenacoelomorpha supported by our phylogenomic analyses implies that the last common ancestor of bilaterians was probably a benthic, ciliated acoelomate worm with a single opening into an epithelial gut, and that excretory organs, coelomic cavities, and nerve cords evolved after xenacoelomorphs separated from the stem lineage of Nephrozoa.

  16. Radial glial cells play a key role in echinoderm neural regeneration

    Science.gov (United States)

    2013-01-01

    Background Unlike the mammalian central nervous system (CNS), the CNS of echinoderms is capable of fast and efficient regeneration following injury and constitutes one of the most promising model systems that can provide important insights into evolution of the cellular and molecular events involved in neural repair in deuterostomes. So far, the cellular mechanisms of neural regeneration in echinoderm remained obscure. In this study we show that radial glial cells are the main source of new cells in the regenerating radial nerve cord in these animals. Results We demonstrate that radial glial cells of the sea cucumber Holothuria glaberrima react to injury by dedifferentiation. Both glia and neurons undergo programmed cell death in the lesioned CNS, but it is the dedifferentiated glial subpopulation in the vicinity of the injury that accounts for the vast majority of cell divisions. Glial outgrowth leads to formation of a tubular scaffold at the growing tip, which is later populated by neural elements. Most importantly, radial glial cells themselves give rise to new neurons. At least some of the newly produced neurons survive for more than 4 months and express neuronal markers typical of the mature echinoderm CNS. Conclusions A hypothesis is formulated that CNS regeneration via activation of radial glial cells may represent a common capacity of the Deuterostomia, which is not invoked spontaneously in higher vertebrates, whose adult CNS does not retain radial glial cells. Potential implications for biomedical research aimed at finding the cure for human CNS injuries are discussed. PMID:23597108

  17. Environmental quality assessment of Grand Harbour (Valletta, Maltese Islands): a case study of a busy harbour in the Central Mediterranean Sea.

    Science.gov (United States)

    Romeo, Teresa; D'Alessandro, Michela; Esposito, Valentina; Scotti, Gianfranco; Berto, Daniela; Formalewicz, Malgorzata; Noventa, Seta; Giuliani, Silvia; Macchia, Simona; Sartori, Davide; Mazzola, Angelo; Andaloro, Franco; Giacobbe, Salvatore; Deidun, Alan; Renzi, Monia

    2015-12-01

    Contamination levels by plastic debris, trace elements and persistent organic pollutants were assessed and related to macrobenthic diversity within soft bottoms of Grand Harbour (Malta, Central Mediterranean). Sediment toxicity was evaluated by ecotoxicological method, deploying Bacteria (Vibrio fischeri), Echinodermata (Paracentrotus lividus) and Crustacea (Corophium orientale). Univariate analysis (Pearson's test) was used to test relationships between biodiversity indices, pollutants and grain size. A multivariate approach (PERMANOVA) was applied to investigate for any significant differences among sampling stations concerning plastic abundances and to test the relationship between infaunal abundances and pollutant concentrations (the BIOENV test). Significant differences in the plastic abundances were found between sampling stations. The lowest value for Shannon-Wiener biodiversity index was associated to the highest sediment pollution level. Multivariate analyses suggest that MBT and TBT were factors that most influenced macrozoobenthic abundance and biodiversity. The bivalve Corbula gibba and the introduced polychaete Monticellina dorsobranchialis were the most abundant found species.

  18. A study on the biodiversity of benthic invertebrates in the waters of Seogwipo, Jeju Island, Korea

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    In-Young Cho

    2014-03-01

    Full Text Available The biodiversity of benthic invertebrates in the intertidal and subtidal regions of Gapado, Beomseom, and Munseom islets was surveyed twice in May and September 2013 to study the state of biodiversity in Seogwipo, Jeju Island. As a result, a total of 77 species, 46 families, 25 orders, 14 classes, and nine phyla of benthic invertebrates were found. The species which were found, by taxon, consisted of the following: 26 species of Cnidaria (34%, 24 species of Mollusca (31%, seven species of Chordata (9%, six species of Arthropoda (8%, six species of Porifera (8%, five species of Echinodermata (7%, one species of Bryozoa (1%, one species of Annelida (1%, and one species of Ctenophora (1%.

  19. Deep water echinoid-associated pontoniine shrimp "Periclimenes hertwigi Balss, 1913" species group (Crustacea: Decapoda: Caridea: Palaemonidae): species review, description of a new genus and species from Philippines.

    Science.gov (United States)

    Marin, Ivan; Chan, Tin-Yam

    2014-07-11

    The new pontoniine shrimp genus, Echinopericlimenes gen. nov., is suggested for four species, Periclimenes hertwigi Balss, 1913, Periclimenes dentidactylus Bruce, 1984, Periclimenes calcaratus Chace & Bruce, 1993 and Echinopericlimenes aurorae sp. nov., belonging to so-called "Periclimenes hertwigi Balss, 1913" species group sensu stricto. The new genus can be clearly separated by the unique form of hepatic tooth greatly extending beyond the pterygostomial margin of carapace, unique form of fingers of pereiopods II (chelipeds) and dactyli of ambulatory pereiopods III-V. All species referring to the new genus are similar in ecology being deep-water dwellers, usually collected deeper that 300 meters in associations with venomous sea urchins of the family Echinothuriidae (Echinodermata: Echinoidea). Remarks on ecology, description of the new species from Philippines and a key to all known species of Echinopericlimenes gen. nov. are presented.

  20. Benthic community productivity in the Magellan Region and in the Weddell Sea

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    Thomas Brey

    1999-12-01

    Full Text Available Our comparison of macrobenthic biomass, production and productivity of the Magellan region (14 - 349 m water depth and the Weddell Sea (132 - 548 m water depth is based on multi box corer samples collected in both areas. Biomass is slightly but not significantly lower in the Magellan region (7.3 g C m-2 than in the Weddell Sea (12.0 g C m-2. Annual production and P/B ratio are higher in the Magellan region (5.1 g C m-2 y-1, 0.7 y-1 as compared to the Weddell Sea (3.6 g C m-2 y-1, 0.3 y-1. In the Magellan region, Mollusca, Polychaeta and Arthropoda dominate benthic production, whereas in the Weddell Sea Polychaeta, Porifera and Echinodermata are the most productive taxa.

  1. Follow-me: A new start-and-stop method for visual animal tracking in biology research.

    Science.gov (United States)

    Linares-Sanchez, Luis Javier; Fernandez-Aleman, Jose Luis; Garcia-Mateos, Gines; Perez-Ruzafa, Angel; Sanchez-Vazquez, Francisco Javier

    2015-08-01

    Very frequently, research in biology and ethology requires visual tracking of live animals, such as insects, rodents and fish. The challenge is particularly difficult in the aquatic environment because of the light scattering effect of water: reflections and refractions, low contrast and resolution images, noise, and also due to the unpredictable animal behavior. This paper describes a new tracking method that is based in start and stop detection. When the animals stop or move very slowly, a precise tracker based on AdaBoost classifiers is applied. Otherwise, when they move faster, a more efficient process based on background detection is used. A control system is responsible for deciding which method should be used in each instant. The experimental results using sea cucumbers (Echinodermata, Holothuroidea), zebrafish and rodents, show the efficiency and accuracy of the proposed method, which is able to deal with complex situations.

  2. Spatial and temporal variability of mobile macro-invertebrate assemblages associated to coralligenous habitat

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    R. BEDINI

    2014-03-01

    Full Text Available The study aimed to investigate patterns of spatial and temporal variability of mobile macroinvertebrate assemblages associated to coralligenous habitat. A multi-factorial sampling design was used to test the hypotheses that the structure of assemblages and their spatial and temporal variability changed in relation to substrate inclination. Moreover, macroalgae and sessile macro-invertebrates were also investigated in order to detect eventual relationship between sessile and mobile assemblages. A total of 236 mobile macro-invertebrate taxa were identified, among them 2 Platyhelminthes, 4 Sipuncula, 6 Nemertea, 27 Mollusca, 86 Annelida, 103 Arthropoda, 8 Echinodermata. Results of the study showed that mobile macro-invertebrate assemblages of coralligenous habitat were little influenced by the inclination of substrate and by the morphology of sessile organisms, as patterns of variation were different between the two assemblages. Mobile macro-invertebrate assemblages changed among sampling dates within one year period and they showed high variability at the spatial scale examined.

  3. Structure of acrosome reaction-inducing substance in the jelly coat of starfish eggs: a mini review.

    Science.gov (United States)

    Hoshi, Motonori; Moriyama, Hideaki; Matsumoto, Midori

    2012-08-31

    Our knowledge at present on the structure of acrosome-reaction inducing substance (ARIS) in the jelly coat of starfish eggs is summarized. ARIS ia a proteoglycan-like molecule consisting of very long, linear, and highly sulfated glycans and three ARIS proteins, ARIS1-3. Detailed structures of the major glycan of ARIS and of ARIS1-3 are discussed. 3D-models of ARIS glycans are also presented. Phylogenetic distribution of ARIS proteins and/or genes indicates that ARIS genes are well preserved from the Ctenophore to Cephalochordata. In the Echinodermata, ARIS1-3 and ARIS genes were detected in all classes except for sea urchins. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Gluconeogenesis: An ancient biochemical pathway with a new twist.

    Science.gov (United States)

    Miyamoto, Tetsuya; Amrein, Hubert

    2017-07-03

    Synthesis of sugars from simple carbon sources is critical for survival of animals under limited nutrient availability. Thus, sugar-synthesizing enzymes should be present across the entire metazoan spectrum. Here, we explore the evolution of glucose and trehalose synthesis using a phylogenetic analysis of enzymes specific for the two pathways. Our analysis reveals that the production of trehalose is the more ancestral biochemical process, found in single cell organisms and primitive metazoans, but also in insects. The gluconeogenic-specific enzyme glucose-6-phosphatase (G6Pase) first appears in Cnidaria, but is also present in Echinodermata, Mollusca and Vertebrata. Intriguingly, some species of nematodes and arthropods possess the genes for both pathways. Moreover, expression data from Drosophila suggests that G6Pase and, hence, gluconeogenesis, initially had a neuronal function. We speculate that in insects-and possibly in some vertebrates-gluconeogenesis may be used as a means of neuronal signaling.

  5. Food habits and seasonal variation of stomach contents of tongue sole Cynoglossus semilaevis (Günther) in the Bohai Sea

    Science.gov (United States)

    Dou, Shuozeng

    1993-03-01

    Examination of the food habits and seasonal variation of the stomach contents of adult tongue sole, Cynoglossus semilaevis (Günther) taken in July 1982 July 1983 from Laizhou Bay and the Huanghe River estuary of the Bohai Sea showed crustacea, bivalvia and small fishes comprised the main prey. Invertebrates such as polychaeta, cephalopoda, gastropoda, echinodermata and actiniaria were also intermittently found in them. They intensively fed all the year found (monthly feeding rate of over 80%). The main food items were Alpheus japonica, Alpheus distinguendus. Oratosquilla oratoria, Eucrate crenata and Carcinoplax vestitus, etc. In summer and autumn, the portion of bivalvia such as Cultellus attenuatus and Musculus senhousei increased steadily. From summer to winter, a stable proportion of small fishes such as Rhinogobius pflaumi and Setipinna taty was in the diet.

  6. MicroRaman, PXRD, EDS and microscopic investigation of magnesium calcite biomineral phases. The case of sea urchin biominerals

    Science.gov (United States)

    Borzęcka-Prokop, B.; Wesełucha-Birczyńska, A.; Koszowska, E.

    2007-02-01

    This study concerns Mg-calcite characterization (and in particular molecular structure and microstructural studies of mineral phases) of a sea urchin mineralised test and spines. Sea urchins are spiny sea animals (kingdom Animalia, phylum Echinodermata, class Echinoidea). Microscopic observations, SEM, EDS, PXRD and spectroscopic microRaman methods have been applied to characterize the biomineral parts of the sea urchin. The latter technique is very useful in research of biological systems and especially suitable for monitoring differences within biomineral phases exhibiting varieties of morphological forms. Crystalline magnesium calcium carbonate, Mg xCa 1- xCO 3 (magnesian calcite; space group R-3 cH; a = 4.9594(8) Å, c = 16.886(6) Å), has been identified as the predominant biomineral component.

  7. Zoogeografía de macroinvertebrados bentónicos de la costa de Chile: contribución para la conservación marina Zoogeography of benthic macroinvertebrates of the Chilean coast: contribution for marine conservation

    Directory of Open Access Journals (Sweden)

    DOMINGO A. LANCELLOTTI

    2000-03-01

    Full Text Available La diversidad de macroinvertebrados marinos ha recibido una atención creciente, no obstante, con un escaso tratamiento en el contexto biogeográfico. Este estudio analiza los registros de 1.601 especies de macroinvertebrados bentónicos pertenecientes a: Demospongiae, Anthozoa, Polychaeta, Mollusca, Crustacea, Echinodermata y Ascideacea, agrupados en 10 zonas y tratados desde una perspectiva zoogeográfica. Mollusca (611 especies, Polychaeta (403 y Crustacea (370 corresponden a los grupos mejor representados a lo largo de la costa chilena, determinantes en el patrón global de la biodiversidad. Este aumenta suavemente de norte a sur, interrumpido por máximos que sugieren esfuerzos diferenciales de estudio más que un comportamiento natural de la biodiversidad. El grado de agrupamiento entre las zonas muestra las tres unidades biogeográficas definidas recientemente por Lancellotti & Vásquez. Este arreglo, que representa lo exhibido por los grupos más diversos, se ve alterado en los grupos menos representados donde las diferencias obedecen al patrón de afinidades mostradas por las zonas comprendidas dentro de la Región Templada Transicional. El quiebre zoogeográfico alrededor de los 41º S, sugerido largamente en la literatura, sólo ocurre en Echinodermata y Demospongiae, evidenciando en los otros taxa la existencia de un área de transición entre los 35º y 48º S, caracterizada por un reemplazo gradual de especies. Dentro de las regiones la biodiversidad muestra homogeneidad, contrario al endemismo, el que alcanza un máximo de 52% en la Región Templada Fría y que parece ser consecuencia del alto número de especies con registros únicos (38,2% de especies citadas para una sóla zona. Esto sugiere un desconocimiento de los macroinvertebrados chilenos (distribución y diversidad, sobrestimando el endemismo regional y distorsionando los patrones locales de biodiversidadThe diversity of marine macroinvertebrates has received increasing

  8. How Hox genes can shed light on the place of echinoderms among the deuterostomes.

    Science.gov (United States)

    David, Bruno; Mooi, Rich

    2014-01-01

    The Hox gene cluster ranks among the greatest of biological discoveries of the past 30 years. Morphogenetic patterning genes are remarkable for the systems they regulate during major ontogenetic events, and for their expressions of molecular, temporal, and spatial colinearity. Recent descriptions of exceptions to these colinearities are suggesting deep phylogenetic signal that can be used to explore origins of entire deuterostome phyla. Among the most enigmatic of these deuterostomes in terms of unique body patterning are the echinoderms. However, there remains no overall synthesis of the correlation between this signal and the variations observable in the presence/absence and expression patterns of Hox genes. Recent data from Hox cluster analyses shed light on how the bizarre shift from bilateral larvae to radial adults during echinoderm ontogeny can be accomplished by equally radical modifications within the Hox cluster. In order to explore this more fully, a compilation of observations on the genetic patterns among deuterostomes is integrated with the body patterning trajectories seen across the deuterostome clade. Synthesis of available data helps to explain morphogenesis along the anterior/posterior axis of echinoderms, delineating the origins and fate of that axis during ontogeny. From this, it is easy to distinguish between 'seriality' along echinoderm rays and true A/P axis phenomena such as colinearity within the somatocoels, and the ontogenetic outcomes of the unique translocation and inversion of the anterior Hox class found within the Echinodermata. An up-to-date summary and integration of the disparate lines of research so far produced on the relationship between Hox genes and pattern formation for all deuterostomes allows for development of a phylogeny and scenario for the evolution of deuterostomes in general, and the Echinodermata in particular.

  9. The complex simplicity of the brittle star nervous system.

    Science.gov (United States)

    Zueva, Olga; Khoury, Maleana; Heinzeller, Thomas; Mashanova, Daria; Mashanov, Vladimir

    2018-01-01

    Brittle stars (Ophiuroidea, Echinodermata) have been increasingly used in studies of animal behavior, locomotion, regeneration, physiology, and bioluminescence. The success of these studies directly depends on good working knowledge of the ophiuroid nervous system. Here, we describe the arm nervous system at different levels of organization, including the microanatomy of the radial nerve cord and peripheral nerves, ultrastructure of the neural tissue, and localization of different cell types using specific antibody markers. We standardize the nomenclature of nerves and ganglia, and provide an anatomically accurate digital 3D model of the arm nervous system as a reference for future studies. Our results helped identify several general features characteristic to the adult echinoderm nervous system, including the extensive anatomical interconnections between the ectoneural and hyponeural components, neuroepithelial organization of the central nervous system, and the supporting scaffold of the neuroepithelium formed by radial glial cells. In addition, we provide further support to the notion that the echinoderm radial glia is a complex and diverse cell population. We also tested the suitability of a range of specific cell-type markers for studies of the brittle star nervous system and established that the radial glial cells are reliably labeled with the ERG1 antibodies, whereas the best neuronal markers are acetylated tubulin, ELAV, and synaptotagmin B. The transcription factor Brn1/2/4 - a marker of neuronal progenitors - is expressed not only in neurons, but also in a subpopulation of radial glia. For the first time, we describe putative ophiuroid proprioceptors associated with the hyponeural part of the central nervous system. Together, our data help establish both the general principles of neural architecture common to the phylum Echinodermata and the specific ophiuroid features.

  10. Conservation and diversification of Msx protein in metazoan evolution.

    Science.gov (United States)

    Takahashi, Hirokazu; Kamiya, Akiko; Ishiguro, Akira; Suzuki, Atsushi C; Saitou, Naruya; Toyoda, Atsushi; Aruga, Jun

    2008-01-01

    Msx (/msh) family genes encode homeodomain (HD) proteins that control ontogeny in many animal species. We compared the structures of Msx genes from a wide range of Metazoa (Porifera, Cnidaria, Nematoda, Arthropoda, Tardigrada, Platyhelminthes, Mollusca, Brachiopoda, Annelida, Echiura, Echinodermata, Hemichordata, and Chordata) to gain an understanding of the role of these genes in phylogeny. Exon-intron boundary analysis suggested that the position of the intron located N-terminally to the HDs was widely conserved in all the genes examined, including those of cnidarians. Amino acid (aa) sequence comparison revealed 3 new evolutionarily conserved domains, as well as very strong conservation of the HDs. Two of the three domains were associated with Groucho-like protein binding in both a vertebrate and a cnidarian Msx homolog, suggesting that the interaction between Groucho-like proteins and Msx proteins was established in eumetazoan ancestors. Pairwise comparison among the collected HDs and their C-flanking aa sequences revealed that the degree of sequence conservation varied depending on the animal taxa from which the sequences were derived. Highly conserved Msx genes were identified in the Vertebrata, Cephalochordata, Hemichordata, Echinodermata, Mollusca, Brachiopoda, and Anthozoa. The wide distribution of the conserved sequences in the animal phylogenetic tree suggested that metazoan ancestors had already acquired a set of conserved domains of the current Msx family genes. Interestingly, although strongly conserved sequences were recovered from the Vertebrata, Cephalochordata, and Anthozoa, the sequences from the Urochordata and Hydrozoa showed weak conservation. Because the Vertebrata-Cephalochordata-Urochordata and Anthozoa-Hydrozoa represent sister groups in the Chordata and Cnidaria, respectively, Msx sequence diversification may have occurred differentially in the course of evolution. We speculate that selective loss of the conserved domains in Msx family

  11. Crown-of-thorns starfish have true image forming vision.

    Science.gov (United States)

    Petie, Ronald; Garm, Anders; Hall, Michael R

    2016-01-01

    Photoreceptors have evolved numerous times giving organisms the ability to detect light and respond to specific visual stimuli. Studies into the visual abilities of the Asteroidea (Echinodermata) have recently shown that species within this class have a more developed visual sense than previously thought and it has been demonstrated that starfish use visual information for orientation within their habitat. Whereas image forming eyes have been suggested for starfish, direct experimental proof of true spatial vision has not yet been obtained. The behavioural response of the coral reef inhabiting crown-of-thorns starfish (Acanthaster planci) was tested in controlled aquarium experiments using an array of stimuli to examine their visual performance. We presented starfish with various black-and-white shapes against a mid-intensity grey background, designed such that the animals would need to possess true spatial vision to detect these shapes. Starfish responded to black-and-white rectangles, but no directional response was found to black-and-white circles, despite equal areas of black and white. Additionally, we confirmed that starfish were attracted to black circles on a white background when the visual angle is larger than 14°. When changing the grey tone of the largest circle from black to white, we found responses to contrasts of 0.5 and up. The starfish were attracted to the dark area's of the visual stimuli and were found to be both attracted and repelled by the visual targets. For crown-of-thorns starfish, visual cues are essential for close range orientation towards objects, such as coral boulders, in the wild. These visually guided behaviours can be replicated in aquarium conditions. Our observation that crown-of-thorns starfish respond to black-and-white shapes on a mid-intensity grey background is the first direct proof of true spatial vision in starfish and in the phylum Echinodermata.

  12. Structures and functions of insect arylalkylamine N-acetyltransferase (iaaNAT; a key enzyme for physiological and behavioral switch in arthropods

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    Susumu eHiragaki

    2015-04-01

    Full Text Available The evolution of N-acetyltransfeases (NATs seems complex. Vertebrate arylalkylamine N-acetyltransferase (aaNAT has been extensively studied since it Leads to the synthesis of melatonin, a multifunctional neurohormone prevalent in photoreceptor cells, and is known as as a chemical token of the night. Melatonin also serves as a scavenger for reactive oxygen species. This is also true with invertebrates. NAT therefore has distinct functional implications in circadian function, as timezymes (aaNAT, and also xenobiotic reactions (arylamine NAT or simply NAT. NATs belong to a broader enzyme group, the GCN5-related N-acetyltransferase superfamily. Due to low sequence homology and a seemingly fast rate of structural differentiation, the nomenclature for NATs can be confusing. The advent of bioinformatics, however, has helped to classify this group of enzymes; vertebrates have two distinct subgroups, the timezyme type and the xenobiotic type, which has a wider substrate range including imidazolamine, pharmacological drugs, environmental toxicants and even histone. Insect aaNAT (iaaNAT form their own clade in the phylogeny, distinct from vertebrate aaNATs. Arthropods are unique, since the phylum has exoskeleton in which quinones derived from N-acetylated monoamines function in coupling chitin and arthropodins. Monoamine oxidase (MAO activity is limited in insects, but NAT-mediated degradation prevails. However, unexpectedly iaaNAT occurs not only among arthropods but also among basal deuterostomia, and is therefore more apomorphic. Our analyses illustrate that iaaNATs has unique physiological roles but at the same time it plays a role in a timezyme function, at least in photoperiodism. Photoperiodism has been considered as a function of circadian system but the detailed molecular mechanism is not well understood. We propose a molecular hypothesis for photoperiodism in Antheraea pernyi based on the transcription regulation of NAT interlocked by the

  13. Ultrastructure of the coelom in the brachiopod Lingula anatina.

    Science.gov (United States)

    Temereva, Elena N

    2017-07-01

    The organization of the coelomic system and the ultrastructure of the coelomic lining are used in phylogenetic analysis to establish the relationships between major taxa. Investigation of the anatomy and ultrastructure of the coelomic system in brachiopods, which are poorly studied, can provide answers to fundamental questions about the evolution of the coelom in coelomic bilaterians. In the current study, the organization of the coelom of the lophophore in the brachiopod Lingula anatina was investigated using semithin sectioning, 3D reconstruction, and transmission electron microscopy. The lophophore of L. anatina contains two main compartments: the preoral coelom and the lophophoral coelom. The lining of the preoral coelom consists of ciliated cells. The lophophoral coelom is subdivided into paired coelomic sacs: the large and small sinuses (= canals). The lining of the lophophoral coelom varies in structure and includes monociliate myoepithelium, alternating epithelial and myoepithelial cells, specialized peritoneum and muscle cells, and podocyte-like cells. Connections between cells of the coelomic lining are provided by adherens junctions, tight-like junctions, septate junctions, adhesive junctions, and direct cytoplasmic bridges. The structure of the coelomic lining varies greatly in both of the main stems of the Bilateria, that is, in the Protostomia and Deuterostomia. Because of this great variety, the structure of the coelomic lining cannot by itself be used in phylogenetic analysis. At the same time, the ciliated myoepithelium can be considered as the ancestral type of coelomic lining. The many different kinds of junctions between cells of the coelomic lining may help coordinate the functioning of epithelial cells and muscle cells. © 2017 Wiley Periodicals, Inc.

  14. Ventralization of an indirect developing hemichordate by NiCl₂ suggests a conserved mechanism of dorso-ventral (D/V) patterning in Ambulacraria (hemichordates and echinoderms).

    Science.gov (United States)

    Röttinger, E; Martindale, M Q

    2011-06-01

    One of the earliest steps in embryonic development is the establishment of the future body axes. Morphological and molecular data place the Ambulacraria (echinoderms and hemichordates) within the Deuterostomia and as the sister taxon to chordates. Extensive work over the last decades in echinoid (sea urchins) echinoderms has led to the characterization of gene regulatory networks underlying germ layer specification and axis formation during embryogenesis. However, with the exception of recent studies from a direct developing hemichordate (Saccoglossus kowalevskii), very little is known about the molecular mechanism underlying early hemichordate development. Unlike echinoids, indirect developing hemichordates retain the larval body axes and major larval tissues after metamorphosis into the adult worm. In order to gain insight into dorso-ventral (D/V) patterning, we used nickel chloride (NiCl₂), a potent ventralizing agent on echinoderm embryos, on the indirect developing enteropneust hemichordate, Ptychodera flava. Our present study shows that NiCl₂ disrupts the D/V axis and induces formation of a circumferential mouth when treated before the onset of gastrulation. Molecular analysis, using newly isolated tissue-specific markers, shows that the ventral ectoderm is expanded at expense of dorsal ectoderm in treated embryos, but has little effect on germ layer or anterior-posterior markers. The resulting ventralized phenotype, the effective dose, and the NiCl₂ sensitive response period of Ptychodera flava, is very similar to the effects of nickel on embryonic development described in larval echinoderms. These strong similarities allow one to speculate that a NiCl₂ sensitive pathway involved in dorso-ventral patterning may be shared between echinoderms, hemichordates and a putative ambulacrarian ancestor. Furthermore, nickel treatments ventralize the direct developing hemichordate, S. kowalevskii indicating that a common pathway patterns both larval and adult

  15. Evolutionary history of the GABA transporter (GAT group revealed by marine invertebrate GAT-1.

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    Azusa Kinjo

    Full Text Available The GABA transporter (GAT group is one of the major subgroups in the solute career 6 (SLC6 family of transmembrane proteins. The GAT group, which has been well studied in mammals, has 6 known members, i.e., a taurine transporter (TAUT, four GABA transporters (GAT-1, -2, -3, - 4, and a creatine transporter (CT1, which have important roles in maintaining physiological homeostasis. However, the GAT group has not been extensively investigated in invertebrates; only TAUT has been reported in marine invertebrates such as bivalves and krills, and GAT-1 has been reported in several insect species and nematodes. Thus, it is unknown how transporters in the GAT group arose during the course of animal evolution. In this study, we cloned GAT-1 cDNAs from the deep-sea mussel, Bathymodiolus septemdierum, and the Antarctic krill, Euphausia superba, whose TAUT cDNA has already been cloned. To understand the evolutionary history of the GAT group, we conducted phylogenetic and synteny analyses on the GAT group transporters of vertebrates and invertebrates. Our findings suggest that transporters of the GAT group evolved through the following processes. First, GAT-1 and CT1 arose by tandem duplication of an ancestral transporter gene before the divergence of Deuterostomia and Protostomia; next, the TAUT gene arose and GAT-3 was formed by the tandem duplication of the TAUT gene; and finally, GAT-2 and GAT-4 evolved from a GAT-3 gene by chromosomal duplication in the ancestral vertebrates. Based on synteny and phylogenetic evidence, the present naming of the GAT group members does not accurately reflect the evolutionary relationships.

  16. Phylogenetic and regulatory region analysis of Wnt5 genes reveals conservation of a regulatory module with putative implication in pancreas development

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    Arhondakis Stilianos

    2010-08-01

    Full Text Available Abstract Background Wnt5 genes belong to the large Wnt family, encoding proteins implicated into several tumorigenic and developmental processes. Phylogenetic analyses showed that Wnt5 gene has been duplicated at the divergence time of gnathostomata from agnatha. Interestingly, experimental data for some species indicated that only one of the two Wnt5 paralogs participates in the development of the endocrine pancreas. The purpose of this paper is to reexamine the phylogenetic history of the Wnt5 developmental regulators and investigate the functional shift between paralogs through comparative genomics. Results In this study, the phylogeny of Wnt5 genes was investigated in species belonging to protostomia and deuterostomia. Furthermore, an in silico regulatory region analysis of Wnt5 paralogs was conducted, limited to those species with insulin producing cells and pancreas, covering the evolutionary distance from agnatha to gnathostomata. Our results confirmed the Wnt5 gene duplication and additionally revealed that this duplication event included also the upstream region. Moreover, within this latter region, a conserved module was detected to which a complex of transcription factors, known to be implicated in embryonic pancreas formation, bind. Conclusions Results and observations presented in this study, allow us to conclude that during evolution, the Wnt5 gene has been duplicated in early vertebrates, and that some paralogs conserved a module within their regulatory region, functionally related to embryonic development of pancreas. Interestingly, our results allowed advancing a possible explanation on why the Wnt5 orthologs do not share the same function during pancreas development. As a final remark, we suggest that an in silico comparative analysis of regulatory regions, especially when associated to published experimental data, represents a powerful approach for explaining shift of roles among paralogs. Reviewers This article was reviewed

  17. Thyroid hormone receptor orthologues from invertebrate species with emphasis on Schistosoma mansoni

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    Niles Edward G

    2007-08-01

    Full Text Available Abstract Background: Thyroid hormone receptors (TRs function as molecular switches in response to thyroid hormone to regulate gene transcription. TRs were previously believed to be present only in chordates. Results: We isolated two TR genes from the Schistosoma mansoni and identified TR orthologues from other invertebrates: the platyhelminths, S. japonium and Schmidtea mediterranea, the mollusc, Lottia gigantean and the arthropod Daphnia pulex. Phylogenetic analysis of the DNA binding domain and/or ligand binding domain shows that invertebrate and vertebrate TRs cluster together, TRs from the vertebrates and from the jawless vertebrate (lamprey clustered within separate subgroups, Platyhelminth TRs cluster outside of the vertebrate TR subgroups and that the schistosome TRs and S. mediterranea TRs clustered within separate subgroups. Alignment of the C-terminus of the A/B domain revealed a conserved TR-specific motif, termed TR 'N-terminus signature sequence', with a consensus sequence of (G/PYIPSY(M/LXXXGPE(D/EX. Heterodimer formation between S. mansoni TRs and SmRXR1 suggests that the invertebrate TR protein gained the ability to form a heterodimer with RXR. ESMA analysis showed that SmTRα could bind to a conserved DNA core motif as a monomer or homodimer. Conclusion: Vertebrate TR genes originated from a common ancestor of the Bilateria. TR genes underwent duplication independently in the Protostomia and Deuterostomia. The duplication of TRs in deuterostomes occurred after the split of jawless and jawed vertebrates. In protostomes, TR genes underwent duplication in Platyhelminths, occurring independently in trematode and turbellarian lineages. Using S. mansoni TRs as an example, invertebrate TRs exhibited the ability to form a dimer with RXR prior to the emergence of the vertebrate TRs and were able to bind to vertebrate TR core DNA elements as a monomer or homodimer.

  18. New insights on the sialidase protein family revealed by a phylogenetic analysis in metazoa.

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    Edoardo Giacopuzzi

    Full Text Available Sialidases are glycohydrolytic enzymes present from virus to mammals that remove sialic acid from oligosaccharide chains. Four different sialidase forms are known in vertebrates: the lysosomal NEU1, the cytosolic NEU2 and the membrane-associated NEU3 and NEU4. These enzymes modulate the cell sialic acid content and are involved in several cellular processes and pathological conditions. Molecular defects in NEU1 are responsible for sialidosis, an inherited disease characterized by lysosomal storage disorder and neurodegeneration. The studies on the biology of sialic acids and sialyltransferases, the anabolic counterparts of sialidases, have revealed a complex picture with more than 50 sialic acid variants selectively present in the different branches of the tree of life. The gain/loss of specific sialoconjugates have been proposed as key events in the evolution of deuterostomes and Homo sapiens, as well as in the host-pathogen interactions. To date, less attention has been paid to the evolution of sialidases. Thus we have conducted a survey on the state of the sialidase family in metazoan. Using an in silico approach, we identified and characterized sialidase orthologs from 21 different organisms distributed among the evolutionary tree: Metazoa relative (Monosiga brevicollis, early Deuterostomia, precursor of Chordata and Vertebrata (teleost fishes, amphibians, reptiles, avians and early and recent mammals. We were able to reconstruct the evolution of the sialidase protein family from the ancestral sialidase NEU1 and identify a new form of the enzyme, NEU5, representing an intermediate step in the evolution leading to the modern NEU3, NEU4 and NEU2. Our study provides new insights on the mechanisms that shaped the substrate specificity and other peculiar properties of the modern mammalian sialidases. Moreover, we further confirm findings on the catalytic residues and identified enzyme loop portions that behave as rapidly diverging regions and may

  19. Phylogenetic and regulatory region analysis of Wnt5 genes reveals conservation of a regulatory module with putative implication in pancreas development.

    Science.gov (United States)

    Kapasa, Maria; Arhondakis, Stilianos; Kossida, Sophia

    2010-08-04

    Wnt5 genes belong to the large Wnt family, encoding proteins implicated into several tumorigenic and developmental processes. Phylogenetic analyses showed that Wnt5 gene has been duplicated at the divergence time of gnathostomata from agnatha. Interestingly, experimental data for some species indicated that only one of the two Wnt5 paralogs participates in the development of the endocrine pancreas. The purpose of this paper is to reexamine the phylogenetic history of the Wnt5 developmental regulators and investigate the functional shift between paralogs through comparative genomics. In this study, the phylogeny of Wnt5 genes was investigated in species belonging to protostomia and deuterostomia. Furthermore, an in silico regulatory region analysis of Wnt5 paralogs was conducted, limited to those species with insulin producing cells and pancreas, covering the evolutionary distance from agnatha to gnathostomata. Our results confirmed the Wnt5 gene duplication and additionally revealed that this duplication event included also the upstream region. Moreover, within this latter region, a conserved module was detected to which a complex of transcription factors, known to be implicated in embryonic pancreas formation, bind. Results and observations presented in this study, allow us to conclude that during evolution, the Wnt5 gene has been duplicated in early vertebrates, and that some paralogs conserved a module within their regulatory region, functionally related to embryonic development of pancreas. Interestingly, our results allowed advancing a possible explanation on why the Wnt5 orthologs do not share the same function during pancreas development. As a final remark, we suggest that an in silico comparative analysis of regulatory regions, especially when associated to published experimental data, represents a powerful approach for explaining shift of roles among paralogs.

  20. The nervous system of Xenacoelomorpha: a genomic perspective.

    Science.gov (United States)

    Perea-Atienza, Elena; Gavilán, Brenda; Chiodin, Marta; Abril, Josep F; Hoff, Katharina J; Poustka, Albert J; Martinez, Pedro

    2015-02-15

    Xenacoelomorpha is, most probably, a monophyletic group that includes three clades: Acoela, Nemertodermatida and Xenoturbellida. The group still has contentious phylogenetic affinities; though most authors place it as the sister group of the remaining bilaterians, some would include it as a fourth phylum within the Deuterostomia. Over the past few years, our group, along with others, has undertaken a systematic study of the microscopic anatomy of these worms; our main aim is to understand the structure and development of the nervous system. This research plan has been aided by the use of molecular/developmental tools, the most important of which has been the sequencing of the complete genomes and transcriptomes of different members of the three clades. The data obtained has been used to analyse the evolutionary history of gene families and to study their expression patterns during development, in both space and time. A major focus of our research is the origin of 'cephalized' (centralized) nervous systems. How complex brains are assembled from simpler neuronal arrays has been a matter of intense debate for at least 100 years. We are now tackling this issue using Xenacoelomorpha models. These represent an ideal system for this work because the members of the three clades have nervous systems with different degrees of cephalization; from the relatively simple sub-epithelial net of Xenoturbella to the compact brain of acoels. How this process of 'progressive' cephalization is reflected in the genomes or transcriptomes of these three groups of animals is the subject of this paper. © 2015. Published by The Company of Biologists Ltd.

  1. Evolution of the globin gene family in deuterostomes: lineage-specific patterns of diversification and attrition.

    Science.gov (United States)

    Hoffmann, Federico G; Opazo, Juan C; Hoogewijs, David; Hankeln, Thomas; Ebner, Bettina; Vinogradov, Serge N; Bailly, Xavier; Storz, Jay F

    2012-07-01

    In the Metazoa, globin proteins display an underlying unity in tertiary structure that belies an extraordinary diversity in primary structures, biochemical properties, and physiological functions. Phylogenetic reconstructions can reveal which of these functions represent novel, lineage-specific innovations, and which represent ancestral functions that are shared with homologous globin proteins in other eukaryotes and even prokaryotes. To date, our understanding of globin diversity in deuterostomes has been hindered by a dearth of genomic sequence data from the Ambulacraria (echinoderms + hemichordates), the sister group of chordates, and the phylum Xenacoelomorpha, which includes xenoturbellids, acoelomorphs, and nemertodermatids. Here, we report the results of a phylogenetic and comparative genomic analysis of the globin gene repertoire of deuterostomes. We first characterized the globin genes of the acorn worm, Saccoglossus kowalevskii, a representative of the phylum Hemichordata. We then integrated genomic sequence data from the acorn worm into a comprehensive analysis of conserved synteny and phylogenetic relationships among globin genes from representatives of the eight lineages that comprise the superphylum Deuterostomia. The primary aims were 1) to unravel the evolutionary history of the globin gene superfamily in deuterostomes and 2) to use the estimated phylogeny to gain insights into the functional evolution of deuterostome globins. Results of our analyses indicate that the deuterostome common ancestor possessed a repertoire of at least four distinct globin paralogs and that different subsets of these ancestral genes have been retained in each of the descendant organismal lineages. In each major deuterostome group, a different subset of ancestral precursor genes underwent lineage-specific expansions of functional diversity through repeated rounds of gene duplication and divergence. By integrating results of the phylogenetic analysis with available

  2. Variación espacio-temporal de Scleractinia, Gorgonacea, Gastropoda, Bivalvia, Cephalopoda, Asteroidea, Echinoidea y Holothuroidea, de fondos someros de la isla San José, Golfo de California

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    Oscar Efraín Holguin Quiñones

    2008-09-01

    Full Text Available Se realizaron seis expediciones a la isla San José, Golfo de California entre los años 1999 y 2000 en donde se llevaron a cabo las observaciones y muestreos. Con base en los muestreos se determinó el componente específico de tres filos de macroinvertebrados bentónicos en nueve localidades: Cnidaria (Scleractinia y Gorgonacea, Mollusca (Gastropoda, Bivalvia y Cephalopoda, y Echinodermata (Echinoidea, Asteroidea y Holothuroidea. La abundancia del macrobentos conspicuo se estimó visualmente mediante buceo libre a una profundidad entre 2 y 6 m a lo largo de dos transectos en banda paralelos a la línea de costa. Se determinó un total de 38 táxones de los tres grupos. Las especies más abundantes son Tripneustes depressus (44,9%, Echinometra vanbruntii (18,3, Phataria unifascialis (8,9%, Centrostephanus coronatus (8,0%, Diadema mexicanum (5% y Eucidaris thouarsii (3,6%. No se encontraron diferencias significativas en la diversidad (H’, equidad (J y riqueza de especies (S entre los meses y localidades. El análisis de similitud identificó a dos grupos de las localidades del litoral oriental y occidental.Space-time variation of Scleractinia, Gorgonacea, Gastropoda, Bivalvia, Cephalopoda, Asteroidea, Echinoidea and Holothuroidea, from shallow bottom in San Jose Island, Gulf of California. Between the years 1999 and 2000, six expeditions were made to Isla San José, in the Gulf of California. Observations and samples were taken of benthic macroinvertebrates in nine locations. Based on the samples, the specific components of three phyla were determined: Cnidaria (Scleractinia and Gorgonacea, Mollusca (Gastropoda, Bivalvia and Cephalopoda, and Echinodermata (Echinoidea and Holothuroidea. The abundance of conspicuous benthic macroinvertebrates was visually estimated through free dives at a depth of between two and six meters along two transects parallel to the coast. A total of 38 taxa in three groups were determined. The most abundant species

  3. Caracterización preliminar de los invertebrados bentónicos capturados accidentalmente en la pesca de camarones en el norte del estado de Río de Janeiro, sudeste de Brasil Preliminary characterization of benthic invertebrates caught as by-catch in the shrimp fishery in the north of the Rio de Janeiro State, southeastern Brazil

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    Igor David da Costa

    2009-01-01

    Full Text Available Para caracterizar la biodiversidad de invertebrados bentónicos que componen la fauna asociada a la pesca de camarones en el puerto del Farol de Sao Thomé, costa norte del estado de Río de Janeiro, se realizaron 11 pescas mensuales en el año 2004 con redes de arrastre de fondo, cuya área de operaciones comprende 3-5 mn desde la línea de costa, entre 22°00'S y 22°20'S. Los datos registrados de cada taxon y/o especie se refieren a la frecuencia de ocurrencia, frecuencia numérica, biomasa, índice de Importancia Relativa y abundancia. En total se registraron 27 especies de invertebrados bentónicos de Porifera, Cnidaria, Mollusca, Annelida, Crustácea, Echinodermata y Bryozoa. Crustácea fue el más representativo, tanto en número de ejemplares de Petrochirus diogenes, Hepatus pudibundus y Callinectes ornatos, como en biomasa de P. diogenes y H. pudibundas. En términos de frecuencia de ocurrencia en los muéstreos, 11 especies (40,7% fueron constantes; 6 (22,2% accesorias y 10 (37,0% accidentales.In order to characterize the biodiversity of the benthic invertebrate by-catch associated with the shrimp fishery at Farol de Sao Thome harbor, northern Rio de Janeiro State, Brazil, in 2004, 11 monthly trawls were conducted using bottom trawl nets between 22°00'S and 22°20'S and from 3 to 5 nm from the shoreline. The analyzed data for each talon and/or species include frequency of occurrence, numeric frequency, biomass, index of Relative Importance, and abundance. In total, 27 benthic invertebrate species were recorded, including Peripheral, Cnidarians, Mollusk, Annelid, Crustacea, Echinodermata, and Bryozoa. The most representative group was Crustacea, both in number of specimens (Petrochirus diogenes, Hepatus pudibundus, Callinectes ornatus and in biomass (P. diogenes, H. pudibundus. In terms of the frequency of occurrence in the samples, 11 species (40.7% were constant, 6 species (22.2% were accessories, and 10 species (37.0% were by-catch.

  4. Proteolytic events are relevant cellular responses during nervous system regeneration of the starfish Marthasterias glacialis.

    Science.gov (United States)

    Ferraz Franco, Catarina; Santos, Romana; Varela Coelho, Ana

    2014-03-17

    The molecular pathways that trigger the amazing intrinsic regenerative ability of echinoderm nervous system are still unknown. In order to approach this subject, a 2D-DIGE proteomic strategy was used, to screen proteome changes during neuronal regeneration in vivo, using starfish (Asteroidea, Echinodermata) as a model. A total of 528 proteins showed significant variations during radial nerve cord regeneration in both soluble and membrane protein-enriched fractions. Several functional classes of proteins known to be involved in axon regeneration events in other model organisms, such as chordates, were identified for the first time in the regenerating echinoderm nervous system. Unexpectedly, most of the identified proteins presented a molecular mass either higher or lower than expected. Such results suggest a functional modulation through protein post-translational modifications, such as proteolysis. Among these are proteins involved in cytoskeleton and microtubule regulators, axon guidance molecules and growth cone modulators, protein de novo synthesis machinery, RNA binding and transport, transcription factors, kinases, lipid signaling effectors and proteins with neuroprotective functions. In summary, the impact of proteolysis during regeneration events is here shown, although requiring further studies to detail on the mechanisms involving this post-transcriptional event on nervous system regeneration. The nervous systems of some organisms present a complete inability of neurons to regrow across a lesion site, which is the case of the adult mammalian central nervous system (CNS). Expanding our knowledge on how other animals regenerate their nervous system offers great potential for groundbreaking biomedical applications towards the enhancement of mammalian CNS regeneration. In order to approach this subject, a 2D-DIGE proteomic strategy was used for the first time, to screen the proteome changes during neuronal regeneration in vivo, using starfish (Asteroidea

  5. Spatial (bio)accumulation of pharmaceuticals, illicit drugs, plasticisers, perfluorinated compounds and metabolites in river sediment, aquatic plants and benthic organisms.

    Science.gov (United States)

    Wilkinson, John L; Hooda, Peter S; Swinden, Julian; Barker, James; Barton, Stephen

    2018-03-01

    Organic contaminants such as pharmaceuticals, personal care products (PPCPs) and other emerging contaminants (ECs) are known to persist in the aquatic environment and many are indicated as endocrine, epigenetic, or other toxicants. Typically, the study of PPCPs/ECs in the aquatic environment is limited to their occurrence dissolved in river water. In this study, accumulation and spatial distribution of thirteen PPCPs/ECs were assessed in aquatic sediment (n = 23), periphyton (biofilm, n = 8), plants Callitriche sp. (n = 8) and Potamogeton sp. (n = 7) as well as amphipod crustaceans (Gammarus pulex, n = 10) and aquatic snails (Bithynia tentaculata, n = 9). All samples (n = 65) were collected from the Hogsmill, Blackwater and Bourne Rivers in southern England. Targeted PPCPs/ECs included pharmaceuticals, plasticisers, perfluorinated compounds, illicit drugs and metabolites. Extraction from solid matrices occurred using ultrasonic-assisted extraction followed by an in-house validated method for solid-phase extraction and subsequent liquid-chromatography tandem mass-spectrometry. Field-derived bioconcentration-factors and biota-sediment accumulation-factors were determined for all studied biota. Residues of studied contaminants were found in all sediment and biota. Concentrations of contaminants were generally higher in biota than sediment. Evidence suggests that the studied aquatic plants may effectively degrade bisphenol-A into its main transformation product hydroxyacetophenone, potentially mediated by cytochrome p450 and internalisation of contaminants into the cellular vacuole. A positive association between both hydrophobicity and PFC chain length and contaminant accumulation was observed in this work. Only PFCs, plasticisers and HAP were classified as either 'bioaccumulative' or 'very bioaccumulative' using BCF criteria established by guidelines of four governments. Contaminants appeared to be differentially bioaccumulative in biota, indicating

  6. The Global Invertebrate Genomics Alliance (GIGA): Developing Community Resources to Study Diverse Invertebrate Genomes

    Science.gov (United States)

    2014-01-01

    Over 95% of all metazoan (animal) species comprise the “invertebrates,” but very few genomes from these organisms have been sequenced. We have, therefore, formed a “Global Invertebrate Genomics Alliance” (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched to facilitate this collaborative venture. PMID:24336862

  7. The Global Invertebrate Genomics Alliance (GIGA): developing community resources to study diverse invertebrate genomes.

    Science.gov (United States)

    Bracken-Grissom, Heather; Collins, Allen G; Collins, Timothy; Crandall, Keith; Distel, Daniel; Dunn, Casey; Giribet, Gonzalo; Haddock, Steven; Knowlton, Nancy; Martindale, Mark; Medina, Mónica; Messing, Charles; O'Brien, Stephen J; Paulay, Gustav; Putnam, Nicolas; Ravasi, Timothy; Rouse, Greg W; Ryan, Joseph F; Schulze, Anja; Wörheide, Gert; Adamska, Maja; Bailly, Xavier; Breinholt, Jesse; Browne, William E; Diaz, M Christina; Evans, Nathaniel; Flot, Jean-François; Fogarty, Nicole; Johnston, Matthew; Kamel, Bishoy; Kawahara, Akito Y; Laberge, Tammy; Lavrov, Dennis; Michonneau, François; Moroz, Leonid L; Oakley, Todd; Osborne, Karen; Pomponi, Shirley A; Rhodes, Adelaide; Santos, Scott R; Satoh, Nori; Thacker, Robert W; Van de Peer, Yves; Voolstra, Christian R; Welch, David Mark; Winston, Judith; Zhou, Xin

    2014-01-01

    Over 95% of all metazoan (animal) species comprise the "invertebrates," but very few genomes from these organisms have been sequenced. We have, therefore, formed a "Global Invertebrate Genomics Alliance" (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched to facilitate this collaborative venture.

  8. The joining (J) chain is present in invertebrates that do not express immunoglobulins.

    Science.gov (United States)

    Takahashi, T; Iwase, T; Takenouchi, N; Saito, M; Kobayashi, K; Moldoveanu, Z; Mestecky, J; Moro, I

    1996-01-01

    Joining (J) chain is a component of polymeric, but not monomeric, immunoglobulin (Ig) molecules and may play a role in their polymerization and transport across epithelial cells. To date, study of the J chain has been confined to vertebrates that produce Ig and in which the J chain displays a considerable degree of structural homology. The role of the J chain in Ig polymerization has been questioned and, since the J chain can be expressed in lymphoid cells that do not produce Ig, it is possible that the J chain may have other functions. To explore this possibility, we have surveyed J-chain gene, mRNA, and protein expression by using reverse transcriptase-coupled PCR, Northern blot analysis, and immunoblot analysis in invertebrate species that do not produce Ig. We report that the J-chain gene is expressed in invertebrates (Mollusca, Annelida, Arthropoda, Echinodermata, and Holothuroidea), as well as in representative vertebrates (Mammalia, Teleostei, Amphibia). Furthermore, J-chain cDNA from the earthworm has a high degree of homology (68-76%) to human, mouse, and bovine J chains. Immunohistochemical studies reveal that the J chain is localized in the mucous cells of body surfaces, intestinal epithelial cells, and macrophage-like cells of the earthworm and slug. This study suggests that the J chain is a primitive polypeptide that arose before the evolution of Ig molecules and remains highly conserved in extent invertebrates and vertebrates. Images Fig. 1 Fig. 3 Fig. 4 PMID:8700853

  9. Antitumor and immune regulation activities of the extracts of some Chinese marine invertebrates

    Science.gov (United States)

    Zhang, Lixin; Fan, Xiao; Han, Lijun

    2005-03-01

    Extracts of 21 marine invertebrates belonging to Coelenterata, Mollusca, Annelida, Bryozoa, Echiura, Arthropoda, Echinodermata and Urochordata were screened for the studies on their antitumor and immune regulation activities. Antitumor activity was determined by MTT method and immune regulation activity was studied using T- and B-lymphocytes in mice spleen in vitro. It was found that the n-butanol part of Asterina pectinifera, the acetic ether part of Tubuaria marina, 95% ethanol extract of Acanthochiton rubrolineatus have a high inhibition rate of 96.7%, 63.9% and 50.5% respectively on tumor cell line HL-60 at the concentration of 0.063 mg/ml. The inhibition rate of the acetic ether part of Tubuaria marina on the tumor cell line A-549 is 65.4% at concentration of 0.063 mg/mL. The 95% ethanol extract of Meretrix meretrix has so outstanding promoting effect on T-lymphocytes that their multiplication increases 25% when the sample concentration is only 1 μg/ml. On B-lymphocytes, the 95% extract of Rapana venosa, at concentration of 100 μg/ml, has a promotion percentage of 60%. On the other hand, under the condition of no cytotoxic effect, the 95% ethanol extracts of Acanthochiton rubrolineatus and Cellana toreum can reach 92% inhibition rate on T lymphocyte at concentration of 100 μg/ml, while the inhibition rate on B lymphocyte of the 95% extract of Acanthochiton rubrolineatus reaches 92% at the same concentration.

  10. Soft-bottom macrobenthic faunal associations in the southern Chilean glacial fjord complex

    Directory of Open Access Journals (Sweden)

    Carlos Ríos

    2005-12-01

    Full Text Available Macrobenthic associations were investigated at 29 sampling stations with a semi-quantitative Agassiz trawl, ranging from the South Patagonian Icefield to the Straits of Magellan in the South Chilean fjord system. A total of 1,895 individuals belonging to 131 species were collected. 19 species belong to colonial organisms, mainly Bryozoa (17 species and Octocorallia (2 species. The phylum Echinodermata was the most diverse in species number (47 species, with asteroids (25 species and ophiuroids (13 species being the best represented within this taxon. Polychaeta was the second dominant group in terms of species richness (46 species. Multidimensional scaling ordination (MDS separated two station groups, one related to fjords and channels off the South Patagonian Icefield and the second one to stations surrounding the Straits of Magellan. 45 species account for 90% of the dissimilarity between these two groups. These differences can mainly be explained by the influence of local environmental conditions determined by processes closely related to the presence/absence of glaciers. Abiotic parameters such as water depth, type of sediment and chemical features of the superficial sediment were not correlated with the numbers of individuals caught by the Agassiz trawl in each group of sampling stations.

  11. Abundance, size composition and benthic assemblages of two Mediterranean echinoids off the

    Directory of Open Access Journals (Sweden)

    Elzahrae Elmasry

    2015-12-01

    Full Text Available This study is concerned with the variability in abundance, size composition and benthic assemblages of two echinoid species, the common sea urchin Paracentrotus lividus (Lamarck, 1816 and black urchin Arbacia lixula (Linnaeus, 1758 in the Southeastern Mediterranean (SEM along the coast of Alexandria, Egypt. Four seasonal trips were made during the years 2014–2015 covering 55 km of the shore with depths ranging between 3 and 9 m. The sea urchin species composition, density and size structure and distribution were compared. The associated macrobenthic invertebrates with prominent presence and biomass were observed as well as other benthic fauna and flora associations. The present results showed that P. lividus was the dominant echinoid spatially and temporally. A. lixula showed frequent occurrence in Sidi Bishr and Sidi Gaber stations in the spring season. The most dominant size class was the medium to large-sized classes for P. lividus and large-sized classes for A. lixula. The commercial size for the edible P. lividus represented 33% of the sampled population. Furthermore, the most dominant macrobenthic assemblages beside the echinoid population were primarily oysters, sea cucumbers, and mussels. Beside these, assemblage of seaweeds (red, green, brown and crustose algae, Porifera, Cnidaria, Crustacea, other Echinodermata, Bivalvia, Gastropoda, Tunicata, Bryozoa and Annelida were found. The present study shows that the investigated area represents stable habitats for the echinoid population with rich and diversified algal assemblages as well as other potential food resources.

  12. Tidal effects on short-term mesozooplankton distribution in small channels of a temperate-turbid estuary, Southwestern Atlantic

    Directory of Open Access Journals (Sweden)

    Javier Chazarreta

    2015-06-01

    Full Text Available Abstract The short-term variability of mesozooplankton distribution and physicochemical variables was examined in two different channels of the Bahía Blanca Estuary, Argentina, during two tidal cycles. All the physicochemical measurements and mesozooplankton sampling were performed at a fixed site during approximately 22-23 h at 3-h intervals. Pumps were used to obtain surface and bottom mesozooplankton samples and the water speed of each stratum was measured with an Acoustic Doppler Current Profiler (ADCP. In all, 23 mesozooplanktonic taxa belonging to four phyla (Arthropoda, Annelida, Echinodermata and Chordata were identified. The most abundant taxa during the two tidal cycles were Balanus glandula larvae, Eurytemora americana and Acartia tonsa. A discernible variability in the water conditions and vertical mesozooplankton distribution (VMD different from that known for the estuary's main channel, was found in the other two selected channels. VMD varied during the tidal cycle in both channels in accordance with the channel's geomorphology and water dynamic characteristics of each of them. The variation of the abundance of the different taxa during ebb and flood currents might indicate the existence of a tidal vertical migration of the mesozooplankton as a response to particular dynamic water conditions.

  13. Enhanced primers for amplification of DNA barcodes from a broad range of marine metazoans.

    Science.gov (United States)

    Lobo, Jorge; Costa, Pedro M; Teixeira, Marcos A L; Ferreira, Maria S G; Costa, Maria H; Costa, Filipe O

    2013-09-10

    Building reference libraries of DNA barcodes is relatively straightforward when specifically designed primers are available to amplify the COI-5P region from a relatively narrow taxonomic group (e.g. single class or single order). DNA barcoding marine communities have been comparatively harder to accomplish due to the broad taxonomic diversity and lack of consistently efficient primers. Although some of the so-called "universal" primers have been relatively successful, they still fail to amplify COI-5P of many marine animal groups, while displaying random success even among species within each group. Here we propose a new pair of primers designed to enhance amplification of the COI-5P region in a wide range of marine organisms. Amplification tests conducted on a wide range of marine animal taxa, rendered possible the first-time sequencing of DNA barcodes from eight separated phyla (Annelida, Arthropoda, Chordata, Cnidaria, Echinodermata, Mollusca, Nemertea and Platyhelminthes), comprising a total of 14 classes, 28 orders, 57 families, 68 genus and 76 species. These primers demonstrated to be highly cost-effective, which is of key importance for DNA barcoding procedures, such as for building comprehensive DNA barcode libraries of marine communities, where the processing of a large numbers of specimens from a wide variety of marine taxa is compulsory.

  14. Phytochemical Screening, Antioxidant Effect and Down Regulation of TGF-β Induced by Ophiocoma erinaceus Brittle Star Crude Extract

    Directory of Open Access Journals (Sweden)

    Javad Baharara

    2015-12-01

    Full Text Available Background: Recent investigations get focused on characterization and isolation of natural compounds with pharmaceutical applications from terrestrial and aquatic ecosystem. Marine invertebrate natural products have been proposed due to various structural diversity. Ophiocoma eraniceus (O. erinaceus is a brittle star species belonging to Echinodermata that distributed in Qeshm island in the Persian Gulf. Recent scientist researches have concentrated on discovery of natural resources with pharmacological and biomedical potential. Objectives: This experiment aimed to discover phytochemical analysis and in vitro antioxidant and anti-inflammatory properties of O. erinaceus methanolic extract. Materials and Methods: In this experimental study, the phytochemical analysis were conducted to determine saponin, phenolic and flavonoid content of brittle star and the free radical scavenging activity with two in vitro assays. In addition, the effect of methanolic brittle star extract on TGF-β expression were analysed by RT-PCR. Results: The phytochemical studies established the presence of saponins, phenol, and flavonoids compounds in the brittle star extract and the antioxidant results from DPPH (1, 1-diphenyl-2-picrylhydrazyl, ABTS (azino-bis-3-ethylbenzothiazoline-6-sulfonic acid revealed that O. erinaceus displayed antioxidant activity as dose dependent manner. On the other hand, O. erinaceus extract inhibited TGF-β expression which indicate anti-inflammatory properties of O. erinaceus. Conclusions: In conclusion, these results clearly exhibited that the O. erinaceus methanolic extract possess valuable constituents that may correspond as a natural antioxidant and anti-inflammatory agent useful in biomedicine.

  15. Assessment of Anti- Inflammatory effect of sea urchin Echinometra mathaei From the Persian Gulf

    Directory of Open Access Journals (Sweden)

    Solmaz Soleimani

    2016-01-01

    Full Text Available Background: sea urchins belonging to phylum echinoderms of marine invertebrates them found to possess excellent. Inflammation can be considered a set of complex processes that many body systems including the immune and nervous system are involved. The aim of the present research was undertaken to study the anti- inflammatory activity of different extracts, coelomic fluid and pigments shells and spines of sea urchin of Echinodermata mathaei. Material and method: Isolation of different tissues extracts (spine, shell, gonad and aristotol lantern sea urchin by three solvents (n- hexan, ethyl acetate, methanol. Isolation coelomic fluid by buffered mode and pigments shell and spine by HCl of sea urchin evaluation antioxidant (DPPH radical scavenging and anti- inflammatory activity investigated through inhibition albumin serum denaturation. Resuts: According to the results of the study, the spine- methanoli and coelomic fluid (CF had the highest activity in the DPPH radical scavenging and aristotol lantern- ethyl acetate and pigment shell highest activity in the anti- inflammatory methods. Significant differences were observed at P<0.05. Conclusion: The result of this research indicated that sea urchin of E.mathaei due to the high antioxidant activity, have anti- inflammatory activities too.

  16. Echinoderms; potential model systems for studies on muscle regeneration

    Science.gov (United States)

    García-Arrarás, José E.; Dolmatov, Igor Yu.

    2010-01-01

    Organisms of the phylum Echinodermata show some of the most impressive regenerative feats within the animal kingdom. Following injury or self-induced autotomy, species in this phylum can regenerate most tissues and organs, being the regeneration of the muscular systems one of the best studied. Even though echinoderms are closely related to chordates, they are little known in the biomedical field, and therefore their uses to study pharmacological effects on muscle formation and/or regeneration have been extremely limited. In order to rectify this lack of knowledge, we describe here the echinoderm muscular systems, particularly the somatic and visceral muscle components. In addition, we provide details of the processes that are known to take place during muscle regeneration, namely dedifferentiation, myogenesis and new muscle formation. Finally, we provide the available information on molecular and pharmacological studies that involve echinoderm muscle regeneration. We expect that by making this information accessible, researchers consider the use of echinoderms as model systems for pharmacological studies in muscle development and regeneration. PMID:20041824

  17. Exploring Canadian Echinoderm Diversity through DNA Barcodes

    Science.gov (United States)

    2016-01-01

    DNA barcoding has proven an effective tool for species identification in varied groups of marine invertebrates including crustaceans, molluscs, polychaetes and echinoderms. In this study, we further validate its utility by analyzing almost half of the 300 species of Echinodermata known from Canadian waters. COI sequences from 999 specimens were assigned to 145 BINs. In most cases, species discrimination was straightforward due to the large difference (25-fold) between mean intra- (0.48%) and inter- (12.0%) specific divergence. Six species were flagged for further taxonomic investigation because specimens assigned to them fell into two or three discrete sequence clusters. The potential influence of larval dispersal capacity and glacial events on patterns of genetic diversity is discussed for 19 trans-oceanic species. Although additional research is needed to clarify biogeographic patterns and resolve taxonomic questions, this study represents an important step in the assembly of a DNA barcode library for all Canadian echinoderms, a valuable resource for future biosurveillance programs. PMID:27870868

  18. Discovery of novel representatives of bilaterian neuropeptide families and reconstruction of neuropeptide precursor evolution in ophiuroid echinoderms.

    Science.gov (United States)

    Zandawala, Meet; Moghul, Ismail; Yañez Guerra, Luis Alfonso; Delroisse, Jérôme; Abylkassimova, Nikara; Hugall, Andrew F; O'Hara, Timothy D; Elphick, Maurice R

    2017-09-01

    Neuropeptides are a diverse class of intercellular signalling molecules that mediate neuronal regulation of many physiological and behavioural processes. Recent advances in genome/transcriptome sequencing are enabling identification of neuropeptide precursor proteins in species from a growing variety of animal taxa, providing new insights into the evolution of neuropeptide signalling. Here, detailed analysis of transcriptome sequence data from three brittle star species, Ophionotus victoriae, Amphiura filiformis and Ophiopsila aranea, has enabled the first comprehensive identification of neuropeptide precursors in the class Ophiuroidea of the phylum Echinodermata. Representatives of over 30 bilaterian neuropeptide precursor families were identified, some of which occur as paralogues. Furthermore, homologues of endothelin/CCHamide, eclosion hormone, neuropeptide-F/Y and nucleobinin/nesfatin were discovered here in a deuterostome/echinoderm for the first time. The majority of ophiuroid neuropeptide precursors contain a single copy of a neuropeptide, but several precursors comprise multiple copies of identical or non-identical, but structurally related, neuropeptides. Here, we performed an unprecedented investigation of the evolution of neuropeptide copy number over a period of approximately 270 Myr by analysing sequence data from over 50 ophiuroid species, with reference to a robust phylogeny. Our analysis indicates that the composition of neuropeptide 'cocktails' is functionally important, but with plasticity over long evolutionary time scales. © 2017 The Authors.

  19. Echinoderms: potential model systems for studies on muscle regeneration.

    Science.gov (United States)

    García-Arrarás, José E; Dolmatov, Igor Yu

    2010-01-01

    Organisms of the phylum Echinodermata show some of the most impressive regenerative feats within the animal kingdom. Following injury or self-induced autotomy, species in this phylum can regenerate most tissues and organs, being the regeneration of the muscular systems one of the best studied. Even though echinoderms are closely related to chordates, they are little known in the biomedical field, and therefore their uses to study pharmacological effects on muscle formation and/or regeneration have been extremely limited. In order to rectify this lack of knowledge, we describe here the echinoderm muscular systems, particularly the somatic and visceral muscle components. In addition, we provide details of the processes that are known to take place during muscle regeneration, namely dedifferentiation, myogenesis and new muscle formation. Finally, we provide the available information on molecular and pharmacological studies that involve echinoderm muscle regeneration. We expect that by making this information accessible, researchers consider the use of echinoderms as model systems for pharmacological studies in muscle development and regeneration.

  20. Exploring Canadian Echinoderm Diversity through DNA Barcodes.

    Directory of Open Access Journals (Sweden)

    Kara K S Layton

    Full Text Available DNA barcoding has proven an effective tool for species identification in varied groups of marine invertebrates including crustaceans, molluscs, polychaetes and echinoderms. In this study, we further validate its utility by analyzing almost half of the 300 species of Echinodermata known from Canadian waters. COI sequences from 999 specimens were assigned to 145 BINs. In most cases, species discrimination was straightforward due to the large difference (25-fold between mean intra- (0.48% and inter- (12.0% specific divergence. Six species were flagged for further taxonomic investigation because specimens assigned to them fell into two or three discrete sequence clusters. The potential influence of larval dispersal capacity and glacial events on patterns of genetic diversity is discussed for 19 trans-oceanic species. Although additional research is needed to clarify biogeographic patterns and resolve taxonomic questions, this study represents an important step in the assembly of a DNA barcode library for all Canadian echinoderms, a valuable resource for future biosurveillance programs.

  1. Ultraviolet radiation and echinoderms: past, present and future perspectives.

    Science.gov (United States)

    Lamare, Miles; Burritt, David; Lister, Kathryn

    2011-01-01

    There is general consensus that solar ultraviolet radiation (UVR) negatively impacts many marine species. Echinoderms are ubiquitous within the marine environment, with members of the phyla often long-lived and numerically dominant within the benthic macrofauna, consequently the impact of UVR on the population dynamics of these organisms will influence marine communities and ecosystems. Research to date has shown that exposure of echinoderms to solar UVR can, affect reproduction and development, change behaviour, cause numerous biochemical and physiological changes and potentially cause increased mutation rates, by causing DNA damage. There is also considerable evidence that echinoderms utilise several different mechanisms to protect themselves against excessive UVR and subsequent UVR-induced damage. However, these protective mechanisms may pose conflicting selection pressures on echinoderms, as UVR is an additional stressor in oceans subjected to anthropogenic-induced climate change. This review summarises our knowledge of the effects of UVR on the Echinodermata. We outline the research conducted to date, highlight key studies on UVR that have utilised echinoderms and look to the future of UVR research in a rapidly changing ocean. 2011 Elsevier Ltd. All rights reserved.

  2. An updated checklist of Echinoderms from Indian waters.

    Science.gov (United States)

    Samuel, Vijay Kumar Deepak; Krishnan, Pandian; Sreeraj, Chemmencheri Ramakrishnan; Chamundeeswari, Kanagaraj; Parthiban, Chermapandi; Sekar, Veeramuthu; Patro, Shesdev; Saravanan, Raju; Abhilash, Kottarathil Rajendran; Ramachandran, Purvaja; Ramesh, Ramachandran

    2017-11-27

    Species checklists enlist the species available within the defined geographical region and thus serve as essential input for developing conservation and management strategies. The fields of conservation biology and ecology confront the challenge of inflated biodiversity, attributed to non-recognition of taxonomic inconsistencies such as synonyms, alternate representation, emendations etc. Critical review of the checklists and distributional records of Phylum Echinodermata from Indian waters and subsequent validation of species names with World Register of Marine Species (WoRMS) database, revealed that the current literature included 236 incorrect entries comprising of 162 synonyms, 15 emendations, 5 nomina dubia, 1 nomen nudum, 40 species under alternate representation, 9 species with author misnomer, 1 subspecies and 1 unaccepted. The 226 species found to be mixed with valid names and a revised checklist was prepared. The revised and updated checklist holds 741 species of echinoderms comprising of 182 asteroids (24.56%), 70 crinoids (9.45%), 138 echinoids (18.62%), 179 holothuroids (24.16%) and 172 ophiuroids (23.21%), placed under 28 orders and 107 families. This paper discusses the cause for taxonomic inflation and argues that such taxonomic inconsistencies alter our interpretations of a species including its inaccurate distribution and, could possibly impede the country's conservation and management efforts.

  3. Diastereoisomer- and species-specific distribution of hexabromocyclododecane (HBCD) in fish and marine invertebrates.

    Science.gov (United States)

    Son, Min-Hui; Kim, Jongchul; Shin, Eun-Su; Seo, Sung-hee; Chang, Yoon-Seok

    2015-12-30

    The levels and distributional characteristics of hexabromocyclododecane (HBCD) diastereoisomers have been largely reported for various fish and select shellfish. In this study, we reclassified a number and variety of marine invertebrates, including shellfish, to further contribute to the comprehensive understanding of the effects and assessment of human exposure to HBCD. Overall, 30 marine invertebrate species (n=188) were investigated and the following order of ∑2HBCD (α- and γ-HBCD) was observed: fish>chordata>cephalopoda>echinodermata>bivalve>crustacea. The marine invertebrates that were reclassified into nektonic and benthic organisms showed similar concentration of ∑2HBCD. The feeding habits and modes of the marine organisms were considered to compare the degree of bioaccumulation and diastereoisomer-specific distribution of HBCD due to the effects of the environment in and around pollution sources, as well as the organisms' metabolic capacities. To the best of our knowledge, this is the first study to examine the species-specific distribution patterns of HBCD for both fish and marine invertebrates. We expect to significantly expand the understanding of the environmental fate of HBCD for marine organisms. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Medicinal benefits of marine invertebrates: sources for discovering natural drug candidates.

    Science.gov (United States)

    De Zoysa, Mahanama

    2012-01-01

    Marine invertebrates are one of the major groups of organisms, which could be diversified under the major taxonomic groups of Porifera, Cnidaria, Mollusca, Arthropoda, Echinodermata, and many other minor phyla. To date, range of medicinal benefits and a significant number of marine natural products (MNPs) have been discovered from marine invertebrates. Seafood diet from edible marine invertebrates such as mollusks and crustaceans has been linked with various medicinal benefits to improve human health. Among marine invertebrates, spongers from phylum Porifera is the most dominant group responsible for discovering large number of MNPs, which have been used as template to develop therapeutic drugs. MNPs isolated from invertebrates have shown wide range of therapeutic properties including antimicrobial, antioxidant, antihypertensive, anticoagulant, anticancer, anti-inflammatory, wound healing and immune modulator, and other medicinal effects. Therefore, marine invertebrates are rich sources of chemical diversity and health benefits for developing drug candidates, cosmetics, nutritional supplements, and molecular probes that can be supported to increase the healthy life span of human. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. The Influence of Oxygen Percentage, Carbon Dioxide Percentage, and Sea Level on the Mean Size and Diversity of Marine Animals during the Cambrian-Neogene Transition

    Science.gov (United States)

    Geronimo, C.; Gao, Y.; Heim, N. A.; Payne, J.

    2016-12-01

    Throughout the course of time, mean body size and diversity have increased arguably due to relationship with environmental factors. Oxygen, carbon dioxide, and sea level are possibly among the most essential environmental factors that influence body size and diversification of marine animals. We test this hypothesis using correlations between animal size and diversity and these environmental variables, but the correlation tests show that oxygen and carbon dioxide levels have no significant relationships with mean body size and diversity in general. According to Pearson's product-moment correlation test, sea level and mean body size of marine animals are inversely related to each other; sea level increases, the mean body sizes decrease or vise versa. Therefore, we looked at trends within individual phyla seeking correlations between the two factors and diversity. Carbon dioxide and oxygen levels are directly related to the diversification of Brachiopoda; sea level is directly related to the diversification of Arthropoda and Echinodermata. Oxygen percentage, carbon dioxide percentage, and sea level have influence toward the increase in mean body size and diversity of marine animals in specific phylum, with the exception of inverse relation between sea level and mean body size. Environmental factors do indeed influence the fluctuation of the mean body size and diversification of marine animals during the Cambrian-Neogene transition, which is proven through correlation test.

  6. Floating mucus aggregates derived from benthic microorganisms on rocky intertidal reefs: Potential as food sources for benthic animals

    Science.gov (United States)

    Tamura, Y.; Tsuchiya, M.

    2011-09-01

    Mucus films, flocs or foams consisting of fine sand, algae and detritus frequently occur in the surface waters of rocky intertidal reef flats during incoming tide. These masses are referred to as mucus aggregates. We examined the developmental process of mucus aggregates and their abundance, distribution, migration and trophic composition. The trophic composition of mucus aggregates was then compared to those of sediments to evaluate their potential nutritional value for benthic animals. The organic matter content, chlorophyll a concentration, microalgal density and bacteria-derived fatty acid contents of mucus aggregates were higher than those observed in sediment, suggesting that mucus aggregates contain not only high levels of organic matter but also dense concentrations of microalgae and bacteria; therefore, mucus aggregates may serve as a qualitatively more energetic food source for benthic fauna compared to sediments. Benthic diatoms were the most abundant organisms in mucus aggregates. Large numbers of diatoms were trapped in fine mineral particles and mucilage-like strings, suggesting that a portion of the mucus is secreted by these benthic microalgae. Mucus aggregate accounted for only 0.01-3.9% of the daily feeding requirements of the dominant detritivore, Ophiocoma scolopendrina (Echinodermata: Ophiuroidea) over the entire sampling area. In contrast, for the species population on the back reef, where mucus aggregates ultimately accumulate, mucus aggregates provided from 0.4 to 113.3% of food for this species. These results suggest that mucus aggregate availability varies spatiotemporally and that they do not always provide adequate food sources for O. scolopendrina populations.

  7. Faunistic assemblages of a sublittoral coarse sand habitat of the northwestern Mediterranean

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    Eva Pubill

    2011-02-01

    Full Text Available The sublittoral megabenthic assemblages of a northwestern Mediterranean coarse sandy beach exploited for the bivalve Callista chione were studied. The spatial and bathymetric variability of its distinctive faunal assemblages was characterised by quantitative sampling performed with a clam dredge. The taxa studied were Mollusca Bivalvia and Gastropoda, Crustacea Decapoda, Echinodermata and Pisces, which accounted for over 99% of the total biomass. Three well-differentiated species assemblages were identified: (1 assemblage MSS (Medium Sand Shallow in medium sand (D50=0.37 mm and shallow waters (mean depth =6.5 m, (2 assemblage CSS (Coarse Sand Shallow in coarse sand (D50=0.62 mm in shallow waters (mean depth =6.7 m, and (3 assemblage CSD (Coarse Sand Deep in coarse sand (D50=0.64 mm in deeper waters (mean depth =16.2 m. Assemblage MSS was characterised by the codominance of the bivalves Mactra stultorum and Acanthocardia tuberculata. C. chione was dominant in both density and biomass in assemblages CSS and CSD. The occurrence of the crab Thia scutellata also characterised assemblage CSS, whereas the occurrence of the sea urchin Echinocardium mediterraneum characterised assemblage CSD. A depth breaking point of around 10 m determined the discontinuity between assemblages CSS and CSD, which was related to the closure depth of the beaches in the study area. Species richness was highest in the coarse sand communities; however, Shannon-Wiener diversity and Pielou equitability indexes were higher in the shallow fine sand community.

  8. 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.

  9. Anticancer Activity of Sea Cucumber Triterpene Glycosides

    Science.gov (United States)

    Aminin, Dmitry L.; Menchinskaya, Ekaterina S.; Pisliagin, Evgeny A.; Silchenko, Alexandra S.; Avilov, Sergey A.; Kalinin, Vladimir I.

    2015-01-01

    Triterpene glycosides are characteristic secondary metabolites of sea cucumbers (Holothurioidea, Echinodermata). They have hemolytic, cytotoxic, antifungal, and other biological activities caused by membranotropic action. These natural products suppress the proliferation of various human tumor cell lines in vitro and, more importantly, intraperitoneal administration in rodents of solutions of some sea cucumber triterpene glycosides significantly reduces both tumor burden and metastasis. The anticancer molecular mechanisms include the induction of tumor cell apoptosis through the activation of intracellular caspase cell death pathways, arrest of the cell cycle at S or G2/M phases, influence on nuclear factors, NF-κB, and up-down regulation of certain cellular receptors and enzymes participating in cancerogenesis, such as EGFR (epidermal growth factor receptor), Akt (protein kinase B), ERK (extracellular signal-regulated kinases), FAK (focal adhesion kinase), MMP-9 (matrix metalloproteinase-9) and others. Administration of some glycosides leads to a reduction of cancer cell adhesion, suppression of cell migration and tube formation in those cells, suppression of angiogenesis, inhibition of cell proliferation, colony formation and tumor invasion. As a result, marked growth inhibition of tumors occurs in vitro and in vivo. Some holothurian triterpene glycosides have the potential to be used as P-gp mediated MDR reversal agents in combined therapy with standard cytostatics. PMID:25756523

  10. Sex steroid receptor evolution and signalling in aquatic invertebrates.

    Science.gov (United States)

    Köhler, Heinz-R; Kloas, Werner; Schirling, Martin; Lutz, Ilka; Reye, Anna L; Langen, Jan-S; Triebskorn, Rita; Nagel, Roland; Schönfelder, Gilbert

    2007-02-01

    In vertebrate reproductive endocrinology sex steroids play a pivotal role via binding to receptors. However, information on the origin and relevance of sex steroids in invertebrates is limited. This review highlights current literature on steroid receptors in aquatic invertebrates and reports on some new findings. It has been shown that invertebrates of the deuterostome clade, such as Acrania and Echinodermata, respond to estrogens and androgens and, at least in Branchiostoma, an estrogen receptor has been cloned. Within the protostomes, most findings are related to aquatic molluscs. Sex steroid receptor-like proteins are abundant in gastropods, bivalves and cephalopods and also sex hormone signalling shows partial similarity to the deuterostomes. In ecdysozoans, however, the impact of sex steroids is still a matter of debate even though there is evidence on the presence of estrogen receptor-like proteins in Crustacea and on physiological effects of estrogens in both Nematoda and Crustacea. Recent findings suggest the presence of an estrogen receptor alpha-like protein of unclear physiological role in Gammarus fossarum (Crustacea). Binding studies revealed the crustacean Hyalella azteca to possess specific binding sites only for androgens but not for estrogens suggesting a possible limitation to functional androgen receptors in this species. Further studies have to be conducted to shed more light into the discussion about the controversy about sex steroid receptors in invertebrates.

  11. Biodiversity of the white coral bank off Cape Santa Maria di Leuca (Mediterranean Sea): An update

    Science.gov (United States)

    Mastrototaro, F.; D'Onghia, G.; Corriero, G.; Matarrese, A.; Maiorano, P.; Panetta, P.; Gherardi, M.; Longo, C.; Rosso, A.; Sciuto, F.; Sanfilippo, R.; Gravili, C.; Boero, F.; Taviani, M.; Tursi, A.

    2010-03-01

    The biodiversity of the Santa Maria di Leuca (SML) coral bank is summarized and its description is updated using data collected by means of underwater video systems, benthic samplers and fishing gears. A total of 222 living species have been recorded within the coral bank area in the depth range 280-1121 m. The most abundant benthic taxa recorded are Porifera (36 species) followed by Mollusca (35) and Cnidaria (31). The scleractinian corals Madrepora oculata and Lophelia pertusa are the main colonial species in the structure of the SML bank. Annelida, Crustacea and Bryozoa have been found with 24, 23 and 19 species, respectively. A total of 40 species of demersal fish have been recorded. Other faunal taxa were found with small numbers of species. One hundred and thirty-five species are new for the SML bank, 31 of which represent new records for the north-western Ionian Sea (2 Porifera, 17 Cnidaria, 1 Mollusca, 3 Annelida, 2 Crustacea, 4 Bryozoa and 4 Echinodermata). The finding of the annelid Harmothoë vesiculosa represents the first record for the Mediterranean Sea. The SML coral bank represents a biodiversity "hot-spot" on the bathyal bottoms of the Mediterranean Sea.

  12. [Space-time variation of Scleractinia, Gorgonacea, Gastropoda, Bivalvia, Cephalopoda, Asteroidea, Echinoidea and Holothuroidea, from shallow bottom in San Jose Island, Gulf of California].

    Science.gov (United States)

    Holguin Quiñones, Oscar Efraín; González Medina, Felipe de Jesús; Solís Marín, Francisco; Félix Pico, Esteban F

    2008-09-01

    Between the years 1999 and 2000, six expeditions were made to Isla San José, in the Gulf of California. Observations and samples were taken of benthic macroinvertebrates in nine locations. Based on the samples, the specific components of three phyla were determined: Cnidaria (Scleractinia and Gorgonacea), Mollusca (Gastropoda, Bivalvia and Cephalopoda), and Echinodermata (Echinoidea and Holothuroidea). The abundance of conspicuous benthic macroinvertebrates was visually estimated through free dives at a depth of between two and six meters along two transects parallel to the coast. A total of 38 taxa in three groups were determined. The most abundant species are Tripneustes depressus (44.9%), Echinometra vanbruntii (18.3%), Phataria unifascialis (8.9%), Centrostephanus coronatus (8.0%), Diadema mexicanum (5%) y Eucidaris thouarsii (3.6%). No significant differences between diversity (H'), equity (J) and richness of the species (S) during the months and site of study. The similarity analysis identified two groups from locations of the eastern and western coasts.

  13. Discovery of sea urchin NGFFFamide receptor unites a bilaterian neuropeptide family.

    Science.gov (United States)

    Semmens, Dean C; Beets, Isabel; Rowe, Matthew L; Blowes, Liisa M; Oliveri, Paola; Elphick, Maurice R

    2015-04-01

    Neuropeptides are ancient regulators of physiology and behaviour, but reconstruction of neuropeptide evolution is often difficult owing to lack of sequence conservation. Here, we report that the receptor for the neuropeptide NGFFFamide in the sea urchin Strongylocentrotus purpuratus (phylum Echinodermata) is an orthologue of vertebrate neuropeptide-S (NPS) receptors and crustacean cardioactive peptide (CCAP) receptors. Importantly, this has facilitated reconstruction of the evolution of two bilaterian neuropeptide signalling systems. Genes encoding the precursor of a vasopressin/oxytocin-type neuropeptide and its receptor duplicated in a common ancestor of the Bilateria. One copy of the precursor retained ancestral features, as seen in highly conserved vasopressin/oxytocin-neurophysin-type precursors. The other copy diverged, but this took different courses in protostomes and deuterostomes. In protostomes, the occurrence of a disulfide bridge in neuropeptide product(s) of the precursor was retained, as in CCAP, but with loss of the neurophysin domain. In deuterostomes, we see the opposite scenario-the neuropeptides lost the disulfide bridge, and neurophysin was retained (as in the NGFFFamide precursor) but was subsequently lost in vertebrate NPS precursors. Thus, the sea urchin NGFFFamide precursor and receptor are 'missing links' in the evolutionary history of neuropeptides that control ecdysis in arthropods (CCAP) and regulate anxiety in humans (NPS).

  14. Seasonal and spatial changes of macrobenthic community structure and diversity in South Yellow Sea

    Science.gov (United States)

    Li, X.; Xu, Y.

    2016-02-01

    The seasonal and spatial characteristics of macrobenthic community in South Yellow Sea were studied based on the data from three voyages carried out in spring, summer and autumn, 2012. A total of 218 species were obtained, including 80 species of Polychaeta, 75 of Crustacea, 35 of Mollusca, 15 of Echinodermata and 13 of other groups. Mean abundance varied from 151.4 ind./m2 in spring to 188 ind./m2 in autumn showing an increasing trend with season and mean biomass ranged from 12.1 g/m2 in spring to 33.4 g/m2 in summer. Mean secondary productivity varied from 2.5 g(AFDW)/(m2·a) in spring to 5.7 g(AFDW)/(m2·a) in summer. Two-way ANOVA indicated that biomass were significantly different among seasons and number of species and Shannon-Weiner index had significant differences among stations. But abundance, Pielou's evenness index and average taxonomic distinctness were not significantly different among either seasons or stations. Non-parametric Kruskal-Wallis test showed significant differences of secondary productivity among tations. Two-way crossed ANOSIM indicated overall significant differences of community structure among both seasons and stations. The stations were divided into four groups in spring and five in summer and autumn through the CLUSTER and nMDS analysis. Depth was an important factor influencing distribution of macrobenthos in the South Yellow Sea.

  15. Feeding habits of Pagellus acarne (Sparidae in the Gulf of Tunis, central Mediterranean

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    Rafika Fehri-Bedoui

    2009-12-01

    Full Text Available The feeding habits of the axillary seabream, Pagellus acarne (Risso, 1810, from the Gulf of Tunis were investigated in relation to season, sex and fish size (juveniles TL < 14.5 cm and adults TL ≥ 14.5 cm. A total of 536 specimens (males, females, unsexed and hermaphroditic, ranging between 11.0 and 25.2 cm TL, were collected with trammel nets from June 2005 to July 2006. Their stomach contents were analysed. Of the total number of examined stomachs, 279 stomachs were empty (Vacuity index, VI = 52%. The VI did not reveal significant seasonal differences when all of the specimens were analysed together; however, significant seasonal variations were observed for females. The diet of the axillary seabream was composed of 36 different prey species. The most important prey were Arthropoda, Mollusca and Echinodermata. Both the dietary indices and the Spearman’s coefficient of correlation indicated seasonal variations in the diet. The diet was more diversified in adults than in juveniles. The axillary seabream fed on a wide range of prey items, endofauna and nekton, and can be considered a carnivorous and euryphagous predator.

  16. Characterization of Circular ssDNA Viruses within the Echinoderm Nanobiome

    Science.gov (United States)

    Jackson, E.; Bistolas, K. S.; Hewson, I.

    2016-02-01

    Viral metagenomics has revealed a great diversity and presence of circular single-stranded(ss) DNA viruses most similar to the viral family Circoviridae in various environments both ambient and host. These viruses are an emerging paradigm in viral discovery amongst aquatic invertebrates mainly from the sub-phlya Crustacea and to a lesser extent the phylum Echinodermata. This parasite-host relationship is furthered here with the discovery of circo-like viruses extracted from the tissue of members from the family Holothuroidea (sea cucumbers). Verification and presence of these viruses within the tissue of the host was confirmed through rigorous genome architecture screening and PCR amplification of the rep gene from unamplified viral DNA extracts. Phylogenetic analysis of the rep gene reveals high similarity to circular ssDNA viruses from environmental metagenomic surveys of marine habitats. The significance of these findings is changing the perception and understanding of circular ssDNA viruses by broadening the known host range and blurring certain defining characteristics established by their pathogenic counterparts. Aside from discover and characterization, the potential ecological impacts of ssDNA viruses upon their host remains relatively unknown and further investigations should aim to determine the pathology, route of infection, and ecological implications of viral infection.

  17. Evidence for a Saponin Biosynthesis Pathway in the Body Wall of the Commercially Significant Sea Cucumber Holothuria scabra

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    Shahida Akter Mitu

    2017-11-01

    Full Text Available The sea cucumber (phylum Echinodermata body wall is the first line of defense and is well known for its production of secondary metabolites; including vitamins and triterpenoid glycoside saponins that have important ecological functions and potential benefits to human health. The genes involved in the various biosynthetic pathways are unknown. To gain insight into these pathways in an echinoderm, we performed a comparative transcriptome analysis and functional annotation of the body wall and the radial nerve of the sea cucumber Holothuria scabra; to define genes associated with body wall metabolic functioning and secondary metabolite biosynthesis. We show that genes related to signal transduction mechanisms were more highly represented in the H. scabra body wall, including genes encoding enzymes involved in energy production. Eight of the core triterpenoid biosynthesis enzymes were found, however, the identity of the saponin specific biosynthetic pathway enzymes remains unknown. We confirm the body wall release of at least three different triterpenoid saponins using solid phase extraction followed by ultra-high-pressure liquid chromatography-quadrupole time of flight-mass spectrometry. The resource we have established will help to guide future research to explore secondary metabolite biosynthesis in the sea cucumber.

  18. Composición y estructura de la macrofauna asociada con agregaciones de dos especies de bivalvos en Isla de Cubagua, Venezuela

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    Iván Hernández-Ávila

    2013-06-01

    Full Text Available Las agregaciones de bivalvos constituyen un microhábitat para una gran variedad de organismos en el ambiente intermareal, submareal y en aguas profundas. Agregaciones de la ostra perla (Pinctada imbricata y pepitona (Arca zebra a diferentes densidades poblacionales se evaluaron para determinar la composición y estructura comunitaria de la macrofauna asociada en tres taxa (Crustacea Decapoda, Mollusca y Echinodermata. La hipótesis nula de no diferencias en descriptores univariados y multivariados fue probada comparando la fauna asociada entre las agregaciones de las dos especies a tres niveles de densidad. En estas agregaciones se identificaron 102 especies de 55 familias. Mithraculus forceps (Majidae, Crucibulum auricula (Calyptraeidae y Ophiotrix angulata (Ophiothrichidae fueron las especies más comunes encontradas en estas asociaciones. Las densidades medias y altas de las agregaciones de bivalvos presentaron mayor número de especies, abundancia, diversidad de Shannon, equidad, diversidad taxonómica y distinción taxonómica de la fauna asociada que las agregaciones de baja densidad poblacional. Análisis multivariados detectaron diferentes estructuras de los ensambles de la fauna asociada en agregaciones de bivalvos con densidad baja en comparación con los de densidad media y alta. Adicionalmente no se detectaron diferencias en la fauna asociada entre las especies. La densidad de las agregaciones de bivalvos, asociada a la complejidad topográfica, es un factor importante para la composición de la fauna asociada.

  19. The Global Invertebrate Genomics Alliance (GIGA): Developing Community Resources to Study Diverse Invertebrate Genomes

    KAUST Repository

    Bracken-Grissom, Heather

    2013-12-12

    Over 95% of all metazoan (animal) species comprise the invertebrates, but very few genomes from these organisms have been sequenced. We have, therefore, formed a Global Invertebrate Genomics Alliance (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site () has been launched to facilitate this collaborative venture.

  20. Extraction and Characterization of Collagen from Sea Cucumber Flesh

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    Alhana

    2015-11-01

    Full Text Available Sea cucumber (Stichopus variegatus is one of the Echinodermata phylum that grows along Indonesian coastal. Sea cucumber is potential source of collagen. The purposes of this research were to determine the optimal concentration of NaOH and CH3COOH solution in collagen production and analyze the physicochemical characteristics of collagen from S. variegatus. Yield of the collagen was 1.5% (based on wet weight basis, produced by pretreatment with NaOH 0,30%, hydrolysis with CH3COOH 0.10% and extracted using distilled water. Protein, moisture, and ash content of the collagen was 67.68%, 13.64%, and 4.15%, respectively. Collagen was extracted using distilled water at 45°C during 2h and still had triple helix structure ; pH 7.37 ; melting temperature 163.67°C and whiteness 69.25%. The major amino acid content of collagen were glycine, alanine, proline and glutamic acid.

  1. A comparison of DNA extraction methods for high-throughput DNA analyses.

    Science.gov (United States)

    Schiebelhut, Lauren M; Abboud, Sarah S; Gómez Daglio, Liza E; Swift, Holly F; Dawson, Michael N

    2017-07-01

    The inclusion of next-generation sequencing technologies in population genetic and phylogenetic studies has elevated the need to balance time and cost of DNA extraction without compromising DNA quality. We tested eight extraction methods - ranging from low- to high-throughput techniques - and eight phyla: Annelida, Arthropoda, Cnidaria, Chordata, Echinodermata, Mollusca, Ochrophyta and Porifera. We assessed DNA yield, purity, efficacy and cost of each method. Extraction efficacy was quantified using the proportion of successful polymerase chain reaction (PCR) amplification of two molecular markers for metazoans (mitochondrial COI and nuclear histone 3) and one for Ochrophyta (mitochondrial nad6) at four time points - 0.5, 1, 2 and 3 years following extraction. DNA yield and purity were quantified using NanoDrop absorbance ratios. Cost was estimated in terms of time and material expense. Results show differences in DNA yield, purity and PCR success between extraction methods and that performance also varied by taxon. The traditional time-intensive, low-throughput CTAB phenol-chloroform extraction performed well across taxa, but other methods also performed well and provide the opportunity to reduce time spent at the bench and increase throughput. © 2016 John Wiley & Sons Ltd.

  2. Unusually long palindromes are abundant in mitochondrial control regions of insects and nematodes.

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    K P Arunkumar

    Full Text Available BACKGROUND: Palindromes are known to be involved in a variety of biological processes. In the present investigation we carried out a comprehensive analysis of palindromes in the mitochondrial control regions (CRs of several animal groups to study their frequency, distribution and architecture to gain insights into the origin of replication of mtDNA. METHODOLOGY/PRINCIPAL FINDINGS: Many species of Arthropoda, Nematoda, Mollusca and Annelida harbor palindromes and inverted repeats (IRs in their CRs. Lower animals like cnidarians and higher animal groups like chordates are almost devoid of palindromes and IRs. The study revealed that palindrome occurrence is positively correlated with the AT content of CRs, and that IRs are likely to give rise to longer palindromes. CONCLUSIONS/SIGNIFICANCE: The present study attempts to explain possible reasons and gives in silico evidence for absence of palindromes and IRs from CR of vertebrate mtDNA and acquisition and retention of the same in insects. Study of CRs of different animal phyla uncovered unique architecture of this locus, be it high abundance of long palindromes and IRs in CRs of Insecta and Nematoda, or short IRs of 10-20 nucleotides with a spacer region of 12-14 bases in subphylum Chelicerata, or nearly complete of absence of any long palindromes and IRs in Vertebrata, Cnidaria and Echinodermata.

  3. Complete mitochondrial genome sequence of the polychaete annelidPlatynereis dumerilii

    Energy Technology Data Exchange (ETDEWEB)

    Boore, Jeffrey L.

    2004-08-15

    Complete mitochondrial genome sequences are now available for 126 metazoans (see Boore 1999; Mitochondrial Genomics link at http://www.jgi.doe.gov), but the taxonomic representation is highly biased. For example, 80 are from a single phylum, Chordata, and show little variation for many molecular features. Arthropoda is represented by 16 taxa, Mollusca by eight, and Echinodermata by five, with only 17 others from the remaining {approx}30 metazoan phyla. With few exceptions (see Wolstenholme 1992 and Boore 1999) these are circular DNA molecules, about 16 kb in size, and encode the same set of 37 genes. A variety of non-standard names are sometimes used for animal mitochondrial genes; see Boore (1999) for gene nomenclature and a table of synonyms. Mitochondrial genome comparisons serve as a model of genome evolution. In this system, much smaller and simpler than that of the nucleus, are all of the same factors of genome evolution, where one may find tractable the changes in tRNA structure, base composition, genetic code, gene arrangement, etc. Further, patterns of mitochondrial gene rearrangements are an exceptionally reliable indicator of phylogenetic relationships (Smith et al.1993; Boore et al. 1995; Boore, Lavrov, and Brown 1998; Boore and Brown 1998, 2000; Dowton 1999; Stechmann and Schlegel 1999; Kurabayashi and Ueshima 2000). To these ends, we are sampling further the variation among major animal groups in features of their mitochondrial genomes.

  4. Antioxidative and anticancer activities of various ethanolic extract fractions from crown-of-thorns starfish (Acanthaster planci).

    Science.gov (United States)

    Lee, Chi-Chiu; Hsieh, Hernyi Justin; Hsieh, Cheng-Hong; Hwang, Deng-Fwu

    2014-11-01

    Many studies currently researching marine invertebrates to determine the therapeutic potential of their bioactive materials have been showing very promising results. The crown-of-thorns starfish Acanthaster planci, an Echinodermata of the class Asteroidea, is infamous as the unique venomous starfish and as a destroyer of coral reefs. Starfish possesses many useful pharmacological and biological characteristics. In this study, A. planci was extracted with 70% ethanol and lyophilized to obtain an ethanol fraction. The ethanol fraction was dissolved with water and defatted with petroleum ether to obtain a non-polar fraction. The residual solution was successively partitioned with ethylacetate and butanol to obtain an ethylacetate fraction and butanol fraction, respectively. Four fractions were used to examine the antioxidant and anticancer properties. The ethanol fraction of A. planci contained the highest antioxidant effects such as ABTS, DPPH, Fe(2+) chelating activity and reducing power when compared with four fractions. Among the four fractions, the butanol fraction was especially shown to inhibit human malignant melanoma A375.S2 cells' proliferation, which is involved in the apoptotic progression. This fraction could induce apoptosis and even necrosis in A375.S2 cells as evidenced by double staining with an Annexin V-FITC and PI assay and DNA fragmentation analysis. These results indicated that the starfish A. planci is a good resource for obtaining the biologically active substances for antioxidant and anticancer effects. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Pharmacological Potential of Phylogenetically Diverse Actinobacteria Isolated from Deep-Sea Coral Ecosystems of the Submarine Avilés Canyon in the Cantabrian Sea.

    Science.gov (United States)

    Sarmiento-Vizcaíno, Aida; González, Verónica; Braña, Alfredo F; Palacios, Juan J; Otero, Luis; Fernández, Jonathan; Molina, Axayacatl; Kulik, Andreas; Vázquez, Fernando; Acuña, José L; García, Luis A; Blanco, Gloria

    2017-02-01

    Marine Actinobacteria are emerging as an unexplored source for natural product discovery. Eighty-seven deep-sea coral reef invertebrates were collected during an oceanographic expedition at the submarine Avilés Canyon (Asturias, Spain) in a range of 1500 to 4700 m depth. From these, 18 cultivable bioactive Actinobacteria were isolated, mainly from corals, phylum Cnidaria, and some specimens of phyla Echinodermata, Porifera, Annelida, Arthropoda, Mollusca and Sipuncula. As determined by 16S rRNA sequencing and phylogenetic analyses, all isolates belong to the phylum Actinobacteria, mainly to the Streptomyces genus and also to Micromonospora, Pseudonocardia and Myceligenerans. Production of bioactive compounds of pharmacological interest was investigated by high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) techniques and subsequent database comparison. Results reveal that deep-sea isolated Actinobacteria display a wide repertoire of secondary metabolite production with a high chemical diversity. Most identified products (both diffusible and volatiles) are known by their contrasted antibiotic or antitumor activities. Bioassays with ethyl acetate extracts from isolates displayed strong antibiotic activities against a panel of important resistant clinical pathogens, including Gram-positive and Gram-negative bacteria, as well as fungi, all of them isolated at two main hospitals (HUCA and Cabueñes) from the same geographical region. The identity of the active extracts components of these producing Actinobacteria is currently being investigated, given its potential for the discovery of pharmaceuticals and other products of biotechnological interest.

  6. [Asteroidea, Echinoidea y Holothuroidea in shallow bottoms of Bahía de Loreto, Baja California Sur, Mexico].

    Science.gov (United States)

    Holguin Quiñones, O; Wright López, H; Solís Marín, F

    2000-12-01

    To evaluate echinoderm distribution, abundance and density a double 50 m transect, with a side observation range of 2.5 m was used at each of 11 stations (bimonthly samplings, Aug. 1997-Febr. 1998). In Bahía de Loreto the Phylum Echinodermata consists of 26 taxa. The greatest mean abundance by transect and mean densities in order of importance for Echinoidea were: Echinometra vanbrunti (94.1 +/- 52.9 ind, 0.25 ind/m2), Centrostephanus coronatus (38.15 +/- 9.15 ind, 0.06 ind/m2), Tripneustes depressus (28.68 +/- 6.86 ind, 0.039 ind/m2), Eucidaris thouarsii (10.66 +/- 3.37 ind, 0.025 ind/m2) and Diadema mexicanum (11.75 +/- 4.92 ind, 0.023 ind/m2); for Asteroidea were: Phataria unifascialis, Mithrodia bradleyi and Acanthaster planci. Asteroidea was the dominant class with 12 species, followed by Echinoidea with ten and Holothuroidea was represented by four species.

  7. Integrative mRNA-miRNA interaction analysis associate with immune response of sea cucumber Apostichopus japonicus based on transcriptome database.

    Science.gov (United States)

    Zhou, Xiaoxu; Chang, Yaqing; Zhan, Yaoyao; Wang, Xiuli; Lin, Kai

    2017-10-18

    MicroRNAs (miRNAs) constitute a family of endogenous non-coding small RNAs that have been demonstrated to be the key effectors in mediating host-pathogen interactions. Additionally, high-throughput sequencing provides unexampled opportunities to identify the pathogenic mechanism underlying miRNAs. In the present study, the target genes of immune-related miRNAs (miR-31, miR-2008, miR-92a, miR-210 and miR-7) and specific miRNAs (miR-2004) in Echinodermata were predicted in silico and validated. Gene ontology (GO) analysis of the target genes of these six miRNAs were conducted to further understand the regulatory function in the host immunity of Apostichopus japonicus (A. japonicus). Among the putative target genes of the six miRNAs, various immune-related targets were annotated, such as Nephl, SEC14Ll, p105, GL2, LYS, FNIAL, mTOR, LITAF, SLC44, TLR3, Apaf-1, and CNTN4. This work will provide valuable genetic resources to understand the interaction of multiple mRNA-miRNAs and the regulation mechanism in the anti-bacterial process in the sea cucumber. Copyright © 2017. Published by Elsevier Ltd.

  8. Investigations of Antibacterial Activity of Methanol and Aqueous Ex-tracts of the Body Wall of Sea Cucumber Holothuria leucospilota on some Human Pathogenic Bacteria

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    M. Nazemi

    2016-04-01

    Full Text Available Introduction & Objective: Holothuria leucospilota, sea cucumber, is a species of the Phylum Echinodermata. Sea cucumbers have the most natural products with biological activity. In this study we investigated the antibacterial activity of aqueous and methanol extract of H. leucospilota used against gram positive and gram negative human pathogenic bacteria. Materials & Methods: 9 Samples of H. leucospilota were harvested from the Hengam Island,. The methanol extract was prepared from the powder of sea cucumber. The antibacterial activity of the extracts was determined by broth dilution methods against clinical Gram-negative bacteria to identify MIC and MBC. Results: Aqueous extract of H. leucospilota was inactive on the bacteria. Methanol extract was active on Gram-negetive bacteria; E. coli, Salmonella typhi and Serratia marcescens. But it killed only Salmonella typhi and Serratia marcescens. The MBC of H. leucospilota methanol extract was 10 mg/ml. Methanol extract was active on all Gram-positive bacteria; B. pumilus, B. cereus and S. aureus but it killed only S. aureus. The MBC of H. leucospilota methanol extract was 40 mg/ml. Conclusion: Based on our results, H. leucospilota methanol extract. can be considered as a source of novel antibiotic. Contrary to many marine organisms, sea cucumbers are active against gram-negative bacteria. (Sci J Hamadan Univ Med Sci 2016; 23 (1:75-82

  9. Food utilization of adult flatfishes co-occurring in the Bohai Sea of China

    Science.gov (United States)

    Shuozeng, Dou

    Stomach contents were examined of 4527 adult individuals of 12 flatfish species collected during the 1982-1983 Bohai Sea Fisheries Resources Investigation. Their food habits, diet diversity, similarity of prey taxa, trophic niche breadth and diet overlap were systematically analysed. Ninety-seven prey species belonging to the Coelenterata, Nemertinea, Polychaeta, Mollusca, Crustacea, Echinodermata, Hemichordata and fish were found and five of them were considered to be principal prey for flatfishes: Alpheus japonicus, Oratosquilla oratoria, Alpheus distinguendus, Loligo japonicus and Crangon affinis. Among the flatfishes, Paralichthys olivaceus was piscivorous, whereas Pseudopleuronectes yokohamae and Pseudopleuronectes herzensteini both had polychaetes and molluscs as their main prey groups. Pleuronichthys cornutus was classified as a polychaete-mollusc eater, with a strong preference for crustaceans. Verasper variegatus, Cynoglossus semilaevis, Eopsetta grigorjewi and Cleisthenes herzensteini ate crustaceans. Kareius bicoloratus was classified as a mollusc-crustacean eater. Cynoglossus abbreviatus, Cynoglossus joyneri and Zebrias zebra were grouped as crustacean-fish eaters. However, Z. zebra also took polychaetes and C. abbreviatus and C. joyneri preyed on some molluscs. Trophic relationships among the flatfishes were complicated, but they occupied distinctive microhabitats in different seasons and selected their specific prey items, which was favourable to the stability of the flatfish community in the Bohai Sea.

  10. Benthic Macrofauna Associated with Submerged Bottoms of a Tectonic Estuary in Tropical Eastern Pacific

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    Carlos E. Guevara-Fletcher

    2011-01-01

    Full Text Available The composition and distribution of the main associations of submerged macrobenthos of Bahía Málaga (Colombian pacific coast, were studied in relation to the distribution of hard and soft substrates and some abiotic factors. Eight localities were sampled during six months: three in the external border of the estuary and five in the inner part. In total, 728 organisms were registered, belonging to 207 species, 132 genera, 86 families, and 14 orders of six invertebrate groups (Porifera, Cnidaria, Polychaeta, Mollusca, Crustacea, and Echinodermata. The submerged bottoms presented soft and hard substrates, with rocks and thick sand in five sites, soft bottoms with fine sand in one, and soft bottoms with slime and clay in two. The temperature and salinity values were higher in the external localities, while dissolved oxygen and pH were higher in the internal localities. The localities with hard substrates presented the highest richness of species while the soft substrates, were characterized by a paucity of species and individuals. The similarity classification analyses showed two groups: one characterized by having 61 species in common and high richness with 113 exclusive species. The other group with low diversity and richness values, 37 species in common and 23 exclusive species.

  11. Selective accumulation of germ-line associated gene products in early development of the sea star and distinct differences from germ-line development in the sea urchin.

    Science.gov (United States)

    Fresques, Tara; Zazueta-Novoa, Vanesa; Reich, Adrian; Wessel, Gary M

    2014-04-01

    Echinodermata is a diverse phylum, a sister group to chordates, and contains diverse organisms that may be useful to understand varied mechanisms of germ-line specification. We tested 23 genes in development of the sea star Patiria miniata that fall into five categories: (1) Conserved germ-line factors; (2) Genes involved in the inductive mechanism of germ-line specification; (3) Germ-line associated genes; (4) Molecules involved in left-right asymmetry; and (5) Genes involved in regulation and maintenance of the genome during early embryogenesis. Overall, our results support the contention that the posterior enterocoel is a source of the germ line in the sea star P. miniata. The germ line in this organism appears to be specified late in embryogenesis, and in a pattern more consistent with inductive interactions amongst cells. This is distinct from the mechanism seen in sea urchins, a close relative of the sea star clad. We propose that P. miniata may serve as a valuable model to study inductive mechanisms of germ-cell specification and when compared with germ-line formation in the sea urchin S. purpuratus may reveal developmental transitions that occur in the evolution of inherited and inductive mechanisms of germ-line specification. Copyright © 2013 Wiley Periodicals, Inc.

  12. Toll-like receptors (TLRs) in aquatic animals: signaling pathways, expressions and immune responses.

    Science.gov (United States)

    Rauta, Pradipta R; Samanta, Mrinal; Dash, Hirak R; Nayak, Bismita; Das, Surajit

    2014-01-01

    The innate system's recognition of non-self and danger signals is mediated by a limited number of germ-line encoded pattern recognition receptors (PRRs) that recognize pathogen associated molecular patterns (PAMPs). Toll-like receptors (TLRs) are single, non-catalytic, membrane-spanning PRRs present in invertebrates and vertebrates. They act by specifically recognizing PAMPs of a variety of microbes and activate signaling cascades to induce innate immunity. A large number of TLRs have been identified in various aquatic animals of phyla Cnidaria, Annelida, Mollusca, Arthropoda, Echinodermata and Chordata. TLRs of aquatic and warm-blooded higher animals exhibit some distinctive features due to their diverse evolutionary lineages. However, majority of them share conserve signaling pathways in pathogen recognition and innate immunity. Functional analysis of novel TLRs in aquatic animals is very important in understanding the comparative immunology between warm-blooded and aquatic animals. In additions to innate immunity, recent reports have highlighted the additional roles of TLRs in adaptive immunity. Therefore, vaccines against many critical diseases of aquatic animals may be made more effective by supplementing TLR activators which will stimulate dendritic cells. This article describes updated information of TLRs in aquatic animals and their structural and functional relationship with warm-blooded animals. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Anticancer Activity of Sea Cucumber Triterpene Glycosides

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    Dmitry L. Aminin

    2015-03-01

    Full Text Available Triterpene glycosides are characteristic secondary metabolites of sea cucumbers (Holothurioidea, Echinodermata. They have hemolytic, cytotoxic, antifungal, and other biological activities caused by membranotropic action. These natural products suppress the proliferation of various human tumor cell lines in vitro and, more importantly, intraperitoneal administration in rodents of solutions of some sea cucumber triterpene glycosides significantly reduces both tumor burden and metastasis. The anticancer molecular mechanisms include the induction of tumor cell apoptosis through the activation of intracellular caspase cell death pathways, arrest of the cell cycle at S or G2/M phases, influence on nuclear factors, NF-κB, and up-down regulation of certain cellular receptors and enzymes participating in cancerogenesis, such as EGFR (epidermal growth factor receptor, Akt (protein kinase B, ERK (extracellular signal-regulated kinases, FAK (focal adhesion kinase, MMP-9 (matrix metalloproteinase-9 and others. Administration of some glycosides leads to a reduction of cancer cell adhesion, suppression of cell migration and tube formation in those cells, suppression of angiogenesis, inhibition of cell proliferation, colony formation and tumor invasion. As a result, marked growth inhibition of tumors occurs in vitro and in vivo. Some holothurian triterpene glycosides have the potential to be used as P-gp mediated MDR reversal agents in combined therapy with standard cytostatics.

  14. Traditional and Modern Biomedical Prospecting: Part II—The Benefits

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    Werner E. G. Müller

    2004-01-01

    Full Text Available The progress in molecular and cell biology has enabled a rational exploitation of the natural resources of the secondary metabolites and biomaterials from sponges (phylum Porifera. It could be established that these natural substances are superior for biomedical application to those obtained by the traditional combinatorial chemical approach. It is now established that the basic structural and functional elements are highly conserved from sponges to the crown taxa within the Protostomia (Drosophila melanogaster and Caenorhabditis elegans and Deuterostomia (human; therefore, it is obvious that the molecular etiology of diseases within the metazoan animals have a common basis. Hence, the major challenge for scientists studying natural product chemistry is to elucidate the target(s of a given secondary metabolite, which is per se highly active and selective. After this step, the potential clinical application can be approached. The potential value of some selected secondary metabolites, all obtained from sponges and their associated microorganisms, is highlighted. Examples of compounds that are already in medical use (inhibition of tumor/virus growth [arabinofuranosyl cytosine and arabinofuranosyl adenine], or are being considered as lead structures (acting as cytostatic and anti-inflammatory secondary metabolites [avarol/avarone], causing induction of apoptosis [sorbicillactone] or as prototypes for the interference with metabolic pathways common in organisms ranging from sponges to humans (modulation of pathways activated by fungal components [aeroplysinin], inhibition of angiogenesis [2-methylthio-1,4-napthoquinone], immune modulating activity [FK506] are discussed in this study. In addition, bioactive proteins from sponges are listed (antibacterial activity [pore-forming protein and tachylectin]. Finally, it is outlined that the skeletal elements—the spicules—serve as blueprints for new biomaterials, especially those based on biosilica

  15. Traditional and Modern Biomedical Prospecting: Part II—the Benefits

    Science.gov (United States)

    2004-01-01

    The progress in molecular and cell biology has enabled a rational exploitation of the natural resources of the secondary metabolites and biomaterials from sponges (phylum Porifera). It could be established that these natural substances are superior for biomedical application to those obtained by the traditional combinatorial chemical approach. It is now established that the basic structural and functional elements are highly conserved from sponges to the crown taxa within the Protostomia (Drosophila melanogaster and Caenorhabditis elegans) and Deuterostomia (human); therefore, it is obvious that the molecular etiology of diseases within the metazoan animals have a common basis. Hence, the major challenge for scientists studying natural product chemistry is to elucidate the target(s) of a given secondary metabolite, which is per se highly active and selective. After this step, the potential clinical application can be approached. The potential value of some selected secondary metabolites, all obtained from sponges and their associated microorganisms, is highlighted. Examples of compounds that are already in medical use (inhibition of tumor/virus growth [arabinofuranosyl cytosine and arabinofuranosyl adenine]), or are being considered as lead structures (acting as cytostatic and anti-inflammatory secondary metabolites [avarol/avarone], causing induction of apoptosis [sorbicillactone]) or as prototypes for the interference with metabolic pathways common in organisms ranging from sponges to humans (modulation of pathways activated by fungal components [aeroplysinin], inhibition of angiogenesis [2-methylthio-1,4-napthoquinone], immune modulating activity [FK506]) are discussed in this study. In addition, bioactive proteins from sponges are listed (antibacterial activity [pore-forming protein and tachylectin]). Finally, it is outlined that the skeletal elements—the spicules—serve as blueprints for new biomaterials, especially those based on biosilica, which might be

  16. Traditional and Modern Biomedical Prospecting: Part II-the Benefits: Approaches for a Sustainable Exploitation of Biodiversity (Secondary Metabolites and Biomaterials from Sponges).

    Science.gov (United States)

    Müller, Werner E G; Schröder, Heinz C; Wiens, Matthias; Perović-Ottstadt, Sanja; Batel, Renato; Müller, Isabel M

    2004-09-01

    The progress in molecular and cell biology has enabled a rational exploitation of the natural resources of the secondary metabolites and biomaterials from sponges (phylum Porifera). It could be established that these natural substances are superior for biomedical application to those obtained by the traditional combinatorial chemical approach. It is now established that the basic structural and functional elements are highly conserved from sponges to the crown taxa within the Protostomia (Drosophila melanogaster and Caenorhabditis elegans) and Deuterostomia (human); therefore, it is obvious that the molecular etiology of diseases within the metazoan animals have a common basis. Hence, the major challenge for scientists studying natural product chemistry is to elucidate the target(s) of a given secondary metabolite, which is per se highly active and selective. After this step, the potential clinical application can be approached. The potential value of some selected secondary metabolites, all obtained from sponges and their associated microorganisms, is highlighted. Examples of compounds that are already in medical use (inhibition of tumor/virus growth [arabinofuranosyl cytosine and arabinofuranosyl adenine]), or are being considered as lead structures (acting as cytostatic and anti-inflammatory secondary metabolites [avarol/avarone], causing induction of apoptosis [sorbicillactone]) or as prototypes for the interference with metabolic pathways common in organisms ranging from sponges to humans (modulation of pathways activated by fungal components [aeroplysinin], inhibition of angiogenesis [2-methylthio-1,4-napthoquinone], immune modulating activity [FK506]) are discussed in this study. In addition, bioactive proteins from sponges are listed (antibacterial activity [pore-forming protein and tachylectin]). Finally, it is outlined that the skeletal elements-the spicules-serve as blueprints for new biomaterials, especially those based on biosilica, which might be

  17. Composición y estructura de la macrofauna asociada con agregaciones de dos especies de bivalvos en Isla de Cubagua, Venezuela Composition and structure of the macrofauna associated with beds of two bivalve species in Cubagua Island, Venezuela

    Directory of Open Access Journals (Sweden)

    Iván Hernández-Ávila

    2013-06-01

    Full Text Available Las agregaciones de bivalvos constituyen un microhábitat para una gran variedad de organismos en el ambiente intermareal, submareal y en aguas profundas. Agregaciones de la ostra perla (Pinctada imbricata y pepitona (Arca zebra a diferentes densidades poblacionales se evaluaron para determinar la composición y estructura comunitaria de la macrofauna asociada en tres taxa (Crustacea Decapoda, Mollusca y Echinodermata. La hipótesis nula de no diferencias en descriptores univariados y multivariados fue probada comparando la fauna asociada entre las agregaciones de las dos especies a tres niveles de densidad. En estas agregaciones se identificaron 102 especies de 55 familias. Mithraculus forceps (Majidae, Crucibulum auricula (Calyptraeidae y Ophiotrix angulata (Ophiothrichidae fueron las especies más comunes encontradas en estas asociaciones. Las densidades medias y altas de las agregaciones de bivalvos presentaron mayor número de especies, abundancia, diversidad de Shannon, equidad, diversidad taxonómica y distinción taxonómica de la fauna asociada que las agregaciones de baja densidad poblacional. Análisis multivariados detectaron diferentes estructuras de los ensambles de la fauna asociada en agregaciones de bivalvos con densidad baja en comparación con los de densidad media y alta. Adicionalmente no se detectaron diferencias en la fauna asociada entre las especies. La densidad de las agregaciones de bivalvos, asociada a la complejidad topográfica, es un factor importante para la composición de la fauna asociada.Bivalve aggregations constitute a microhabitat for a wide variety of organisms in intertidal, subtidal and deep-water marine benthic habitats. Increase in density of bivalve beds could offer more crevices and substratum for the associated fauna, affecting community composition. Beds of the Atlantic Pearl Oyster (Pinctada imbricata and the Turkey Wing (Arca zebra of contrasting population densities were evaluated to determine

  18. Trends in the discovery of new marine natural products from invertebrates over the last two decades--where and what are we bioprospecting?

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    Miguel Costa Leal

    Full Text Available It is acknowledged that marine invertebrates produce bioactive natural products that may be useful for developing new drugs. By exploring untapped geographical sources and/or novel groups of organisms one can maximize the search for new marine drugs to treat human diseases. The goal of this paper is to analyse the trends associated with the discovery of new marine natural products from invertebrates (NMNPI over the last two decades. The analysis considers different taxonomical levels and geographical approaches of bioprospected species. Additionally, this research is also directed to provide new insights into less bioprospected taxa and world regions. In order to gather the information available on NMNPI, the yearly-published reviews of Marine Natural Products covering 1990-2009 were surveyed. Information on source organisms, specifically taxonomical information and collection sites, was assembled together with additional geographical information collected from the articles originally describing the new natural product. Almost 10000 NMNPI were discovered since 1990, with a pronounced increase between decades. Porifera and Cnidaria were the two dominant sources of NMNPI worldwide. The exception was polar regions where Echinodermata dominated. The majority of species that yielded the new natural products belong to only one class of each Porifera and Cnidaria phyla (Demospongiae and Anthozoa, respectively. Increased bioprospecting efforts were observed in the Pacific Ocean, particularly in Asian countries that are associated with the Japan Biodiversity Hotspot and the Kuroshio Current. Although results show comparably less NMNPI from polar regions, the number of new natural products per species is similar to that recorded for other regions. The present study provides information to future bioprospecting efforts addressing previously unexplored taxonomic groups and/or regions. We also highlight how marine invertebrates, which in some cases have no

  19. Biosynthesis of Polyunsaturated Fatty Acids in Sea Urchins: Molecular and Functional Characterisation of Three Fatty Acyl Desaturases from Paracentrotus lividus (Lamark 1816)

    Science.gov (United States)

    Carboni, Stefano; Davie, Andrew; Oboh, Angela

    2017-01-01

    Sea urchins are broadly recognised as a delicacy and their quality as food for humans is highly influenced by their diet. Lipids in general and the long-chain polyunsaturated fatty acids (LC-PUFA) in particular, are essential nutrients that determine not only the nutritional value of sea urchins but also guarantee normal growth and reproduction in captivity. The contribution of endogenous production (biosynthesis) of LC-PUFA in sea urchins remained unknown. Using Paracentrotus lividus as our model species, we aimed to characterise both molecularly and functionally the repertoire of fatty acyl desaturases (Fads), key enzymes in the biosynthesis of LC-PUFA, in sea urchins. Three Fads, namely FadsA, FadsC1 and FadsC2, were characterised. The phylogenetic analyses suggested that the repertoire of Fads within the Echinodermata phylum varies among classes. On one hand, orthologues of the P. lividus FadsA were found in other echinoderm classes including starfishes, brittle stars and sea cucumbers, thus suggesting that this desaturase is virtually present in all echinoderms. Contrarily, the FadsC appears to be sea urchin-specific desaturase. Finally, a further desaturase termed as FadsB exists in starfishes, brittle stars and sea cucumbers, but appears to be missing in sea urchins. The functional characterisation of the P. lividus Fads confirmed that the FadsA was a Δ5 desaturase with activity towards saturated and polyunsaturated fatty acids (FA). Moreover, our experiments confirmed that FadsA plays a role in the biosynthesis of non-methylene interrupted FA, a group of compounds typically found in marine invertebrates. On the other hand, both FadsC desaturases from P. lividus showed Δ8 activity. The present results demonstrate that P. lividus possesses desaturases that account for all the desaturation reactions required to biosynthesis the physiological essential eicosapentaenoic and arachidonic acids through the so-called “Δ8 pathway”. PMID:28052125

  20. Arrays in rays: terminal addition in echinoderms and its correlation with gene expression.

    Science.gov (United States)

    Mooi, Rich; David, Bruno; Wray, Gregory A

    2005-01-01

    The echinoderms are deuterostomes that superimpose radial symmetry upon bilateral larval morphology. Consequently, they are not the first animals that come to mind when the concepts of segmentation and terminal addition are being discussed. However, it has long been recognized that echinoderms have serial elements along their radii formed in accordance with the ocular plate rule (OPR). The OPR is a special case of terminal growth, forming elements of the ambulacra that define the rays in echinoderms. New elements are added at the terminus of the ray, which may or may not be marked by a calcified element called the terminal plate (the "ocular" of sea urchins). The OPR operates in every echinoderm, from the occasionally bizarre fossils of the Cambrian to the most familiar extant taxa. Using the OPR and other criteria of recognition, echinoderm body wall can be divided into two main regions: extraxial components are associated with the somatocoels, axial components (formed in accordance with the OPR) with the hydrocoel. We compare patterns of development in axial regions of echinoderms with those found in the anterior-posterior axes of the earliest echinoderms as well as other invertebrates. Although axial and extraxial skeletons appear to be composed of the same biomineral matrix, the genes involved in patterning these two skeletal components are likely distinct. During development of the axial skeleton, for instance, the genes engrailed and orthodenticle are expressed in spatial and temporal patterns consistent with the OPR. Other genes such as distal-less seem to demarcate early ontogenetic boundaries between the axial rudiment and the extraxial larval body. There is a complex and pervasive reorganization of gene expression domains to produce the highly divergent morphologies seen in the Echinodermata. We integrate morphological and genetic information, particularly with respect to the origins of radial symmetry in the rudiment, and the concomitant development of

  1. Ancestral state reconstruction by comparative analysis of a GRN kernel operating in echinoderms.

    Science.gov (United States)

    Erkenbrack, Eric M; Ako-Asare, Kayla; Miller, Emily; Tekelenburg, Saira; Thompson, Jeffrey R; Romano, Laura

    2016-01-01

    Diverse sampling of organisms across the five major classes in the phylum Echinodermata is beginning to reveal much about the structure and function of gene regulatory networks (GRNs) in development and evolution. Sea urchins are the most studied clade within this phylum, and recent work suggests there has been dramatic rewiring at the top of the skeletogenic GRN along the lineage leading to extant members of the euechinoid sea urchins. Such rewiring likely accounts for some of the observed developmental differences between the two major subclasses of sea urchins-cidaroids and euechinoids. To address effects of topmost rewiring on downstream GRN events, we cloned four downstream regulatory genes within the skeletogenic GRN and surveyed their spatiotemporal expression patterns in the cidaroid Eucidaris tribuloides. We performed phylogenetic analyses with homologs from other non-vertebrate deuterostomes and characterized their spatiotemporal expression by quantitative polymerase chain reaction (qPCR) and whole-mount in situ hybridization (WMISH). Our data suggest the erg-hex-tgif subcircuit, a putative GRN kernel, exhibits a mesoderm-specific expression pattern early in Eucidaris development that is directly downstream of the initial mesodermal GRN circuitry. Comparative analysis of the expression of this subcircuit in four echinoderm taxa allowed robust ancestral state reconstruction, supporting hypotheses that its ancestral function was to stabilize the mesodermal regulatory state and that it has been co-opted and deployed as a unit in mesodermal subdomains in distantly diverged echinoderms. Importantly, our study supports the notion that GRN kernels exhibit structural and functional modularity, locking down and stabilizing clade-specific, embryonic regulatory states.

  2. Excellent amino acid racemization results from Holocene sand dollars

    Science.gov (United States)

    Kosnik, M.; Kaufman, D. S.; Kowalewski, M.; Whitacre, K.

    2015-12-01

    Amino acid racemization (AAR) is widely used as a cost-effective method to date molluscs in time-averaging and taphonomic studies, but it has not been attempted for echinoderms despite their paleobiological importance. Here we demonstrate the feasibility of AAR geochronology in Holocene aged Peronella peronii (Echinodermata: Echinoidea) collected from Sydney Harbour (Australia). Using standard HPLC methods we determined the extent of AAR in 74 Peronella tests and performed replicate analyses on 18 tests. We sampled multiple areas of two individuals and identified the outer edge as a good sampling location. Multiple replicate analyses from the outer edge of 18 tests spanning the observed range of D/Ls yielded median coefficients of variation 0.95) for these four amino acids. The ages of 11 individuals spanning the observed range of D/L values were determined using 14C analyses, and Bayesian model averaging was used to determine the best AAR age model. The averaged age model was mainly composed of time-dependent reaction kinetics models (TDK, 71%) based on phenylalanine (Phe, 94%). Modelled ages ranged from 14 to 5539 yrs, and the median 95% confidence interval for the 74 analysed individuals is ±28% of the modelled age. In comparison, the median 95% confidence interval for the 11 calibrated 14C ages was ±9% of the median age estimate. Overall Peronella yields exceptionally high-quality AAR D/L values and appears to be an excellent substrate for AAR geochronology. This work opens the way for time-averaging and taphonomic studies of echinoderms similar to those in molluscs.

  3. Trends in the Discovery of New Marine Natural Products from Invertebrates over the Last Two Decades – Where and What Are We Bioprospecting?

    Science.gov (United States)

    Leal, Miguel Costa; Puga, João; Serôdio, João; Gomes, Newton C. M.; Calado, Ricardo

    2012-01-01

    It is acknowledged that marine invertebrates produce bioactive natural products that may be useful for developing new drugs. By exploring untapped geographical sources and/or novel groups of organisms one can maximize the search for new marine drugs to treat human diseases. The goal of this paper is to analyse the trends associated with the discovery of new marine natural products from invertebrates (NMNPI) over the last two decades. The analysis considers different taxonomical levels and geographical approaches of bioprospected species. Additionally, this research is also directed to provide new insights into less bioprospected taxa and world regions. In order to gather the information available on NMNPI, the yearly-published reviews of Marine Natural Products covering 1990–2009 were surveyed. Information on source organisms, specifically taxonomical information and collection sites, was assembled together with additional geographical information collected from the articles originally describing the new natural product. Almost 10000 NMNPI were discovered since 1990, with a pronounced increase between decades. Porifera and Cnidaria were the two dominant sources of NMNPI worldwide. The exception was polar regions where Echinodermata dominated. The majority of species that yielded the new natural products belong to only one class of each Porifera and Cnidaria phyla (Demospongiae and Anthozoa, respectively). Increased bioprospecting efforts were observed in the Pacific Ocean, particularly in Asian countries that are associated with the Japan Biodiversity Hotspot and the Kuroshio Current. Although results show comparably less NMNPI from polar regions, the number of new natural products per species is similar to that recorded for other regions. The present study provides information to future bioprospecting efforts addressing previously unexplored taxonomic groups and/or regions. We also highlight how marine invertebrates, which in some cases have no commercial value

  4. The venus kinase receptor (VKR) family: structure and evolution

    Science.gov (United States)

    2013-01-01

    Background Receptor tyrosine kinases (RTK) form a family of transmembrane proteins widely conserved in Metazoa, with key functions in cell-to-cell communication and control of multiple cellular processes. A new family of RTK named Venus Kinase Receptor (VKR) has been described in invertebrates. The VKR receptor possesses a Venus Fly Trap (VFT) extracellular module, a bilobate structure that binds small ligands to induce receptor kinase activity. VKR was shown to be highly expressed in the larval stages and gonads of several invertebrates, suggesting that it could have functions in development and/or reproduction. Results Analysis of recent genomic data has allowed us to extend the presence of VKR to five bilaterian phyla (Platyhelminthes, Arthropoda, Annelida, Mollusca, Echinodermata) as well as to the Cnidaria phylum. The presence of NveVKR in the early-branching metazoan Nematostella vectensis suggested that VKR arose before the bilaterian radiation. Phylogenetic and gene structure analyses showed that the 40 receptors identified in 36 animal species grouped monophyletically, and likely evolved from a common ancestor. Multiple alignments of tyrosine kinase (TK) and VFT domains indicated their important level of conservation in all VKRs identified up to date. We showed that VKRs had inducible activity upon binding of extracellular amino-acids and molecular modeling of the VFT domain confirmed the structure of the conserved amino-acid binding site. Conclusions This study highlights the presence of VKR in a large number of invertebrates, including primitive metazoans like cnidarians, but also its absence from nematodes and chordates. This little-known RTK family deserves to be further explored in order to determine its evolutionary origin, its possible interest for the emergence and specialization of Metazoa, and to understand its function in invertebrate development and/or reproductive biology. PMID:23721482

  5. Distribution and evolution of the serine/aspartate racemase family in invertebrates.

    Science.gov (United States)

    Uda, Kouji; Abe, Keita; Dehara, Yoko; Mizobata, Kiriko; Sogawa, Natsumi; Akagi, Yuki; Saigan, Mai; Radkov, Atanas D; Moe, Luke A

    2016-02-01

    Free D-amino acids have been found in various invertebrate phyla, while amino acid racemase genes have been identified in few species. The purpose of this study is to elucidate the distribution, function, and evolution of amino acid racemases in invertebrate animals. We searched the GenBank databases, and found 11 homologous serine racemase genes from eight species in eight different invertebrate phyla. The cloned genes were identified based on their maximum activity as Acropora millepora (Cnidaria) serine racemase (SerR) and aspartate racemase (AspR), Caenorhabditis elegans (Nematoda) SerR, Capitella teleta (Annelida) SerR, Crassostrea gigas (Mollusca) SerR and AspR, Dugesia japonica (Platyhelminthes) SerR, Milnesium tardigradum (Tardigrada) SerR, Penaeus monodon (Arthropoda) SerR and AspR and Strongylocentrotus purpuratus (Echinodermata) AspR. We found that Acropora, Aplysia, Capitella, Crassostrea and Penaeus had two amino acid racemase paralogous genes and these paralogous genes have evolved independently by gene duplication at their recent ancestral species. The transcriptome analyses using available SRA data and enzyme kinetic data suggested that these paralogous genes are expressed in different tissues and have different functions in vivo. Phylogenetic analyses clearly indicated that animal SerR and AspR are not separated by their particular racemase functions and form a serine/aspartate racemase family cluster. Our results revealed that SerR and AspR are more widely distributed among invertebrates than previously known. Moreover, we propose that the triple serine loop motif at amino acid positions 150-152 may be responsible for the large aspartate racemase activity and the AspR evolution from SerR.

  6. Biosynthesis of Polyunsaturated Fatty Acids in Sea Urchins: Molecular and Functional Characterisation of Three Fatty Acyl Desaturases from Paracentrotus lividus (Lamark 1816).

    Science.gov (United States)

    Kabeya, Naoki; Sanz-Jorquera, Alicia; Carboni, Stefano; Davie, Andrew; Oboh, Angela; Monroig, Oscar

    2017-01-01

    Sea urchins are broadly recognised as a delicacy and their quality as food for humans is highly influenced by their diet. Lipids in general and the long-chain polyunsaturated fatty acids (LC-PUFA) in particular, are essential nutrients that determine not only the nutritional value of sea urchins but also guarantee normal growth and reproduction in captivity. The contribution of endogenous production (biosynthesis) of LC-PUFA in sea urchins remained unknown. Using Paracentrotus lividus as our model species, we aimed to characterise both molecularly and functionally the repertoire of fatty acyl desaturases (Fads), key enzymes in the biosynthesis of LC-PUFA, in sea urchins. Three Fads, namely FadsA, FadsC1 and FadsC2, were characterised. The phylogenetic analyses suggested that the repertoire of Fads within the Echinodermata phylum varies among classes. On one hand, orthologues of the P. lividus FadsA were found in other echinoderm classes including starfishes, brittle stars and sea cucumbers, thus suggesting that this desaturase is virtually present in all echinoderms. Contrarily, the FadsC appears to be sea urchin-specific desaturase. Finally, a further desaturase termed as FadsB exists in starfishes, brittle stars and sea cucumbers, but appears to be missing in sea urchins. The functional characterisation of the P. lividus Fads confirmed that the FadsA was a Δ5 desaturase with activity towards saturated and polyunsaturated fatty acids (FA). Moreover, our experiments confirmed that FadsA plays a role in the biosynthesis of non-methylene interrupted FA, a group of compounds typically found in marine invertebrates. On the other hand, both FadsC desaturases from P. lividus showed Δ8 activity. The present results demonstrate that P. lividus possesses desaturases that account for all the desaturation reactions required to biosynthesis the physiological essential eicosapentaenoic and arachidonic acids through the so-called "Δ8 pathway".

  7. Biosynthesis of Polyunsaturated Fatty Acids in Sea Urchins: Molecular and Functional Characterisation of Three Fatty Acyl Desaturases from Paracentrotus lividus (Lamark 1816.

    Directory of Open Access Journals (Sweden)

    Naoki Kabeya

    Full Text Available Sea urchins are broadly recognised as a delicacy and their quality as food for humans is highly influenced by their diet. Lipids in general and the long-chain polyunsaturated fatty acids (LC-PUFA in particular, are essential nutrients that determine not only the nutritional value of sea urchins but also guarantee normal growth and reproduction in captivity. The contribution of endogenous production (biosynthesis of LC-PUFA in sea urchins remained unknown. Using Paracentrotus lividus as our model species, we aimed to characterise both molecularly and functionally the repertoire of fatty acyl desaturases (Fads, key enzymes in the biosynthesis of LC-PUFA, in sea urchins. Three Fads, namely FadsA, FadsC1 and FadsC2, were characterised. The phylogenetic analyses suggested that the repertoire of Fads within the Echinodermata phylum varies among classes. On one hand, orthologues of the P. lividus FadsA were found in other echinoderm classes including starfishes, brittle stars and sea cucumbers, thus suggesting that this desaturase is virtually present in all echinoderms. Contrarily, the FadsC appears to be sea urchin-specific desaturase. Finally, a further desaturase termed as FadsB exists in starfishes, brittle stars and sea cucumbers, but appears to be missing in sea urchins. The functional characterisation of the P. lividus Fads confirmed that the FadsA was a Δ5 desaturase with activity towards saturated and polyunsaturated fatty acids (FA. Moreover, our experiments confirmed that FadsA plays a role in the biosynthesis of non-methylene interrupted FA, a group of compounds typically found in marine invertebrates. On the other hand, both FadsC desaturases from P. lividus showed Δ8 activity. The present results demonstrate that P. lividus possesses desaturases that account for all the desaturation reactions required to biosynthesis the physiological essential eicosapentaenoic and arachidonic acids through the so-called "Δ8 pathway".

  8. Sea urchin: toxinology, bioactive compounds and its treatment management

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    Gholamhossein Mohebbi

    2016-09-01

    Full Text Available Background: The sea urchins are classified in the echinoderms category because of their spiny skin. Saponins are the major responsible metabolites for Echinodermata biological activities . As mentioned before, about 80 species of sea urchins are venomous for human. Their spine, pedicellariae, and some other organs such as gonads and coelomic fluids contain different toxins and bioactive compounds. This review study have evaluated toxinology and bioactive compounds from the extracts, and treatment management of these venomous animals. Results: Contractin A, echinochrome A, echinometrin, major yolk protein (MYP, centrocins (I, II(, cathepsin B/X, strongylostatins (I,II, vitellogenin, UT841 toxin, spinochrome, and pedoxin as the prosthetic group of peditoxin are the most important compounds obtained from these animals. Some people show poisoning symptoms following the ingestion of sea urchin gonads, especially during the breeding season. Some of these symptoms included allergies symptoms, as the first symptoms, nausea, diarrhea, vomiting, epigastric distress, severe headache, swelling of the lips and mouth, salivation, abdominal pain and some systemic symptoms such as hypotension, numbness and weakness. The most injuries by sea urchin can cause by contact to spines, which can create the various complications such as granuloma, synovitis, arthritis, edema, hyperkeratosis and even neuroma. Injuries by pedicellaria may cause severe pain, local edema, bleeding, lethargy, weakness, tingling, joint pain, aphonia, dizziness, syncope, general muscle paralysis, respiratory distress, hypotension and, infrequently death. After the injury by sea urchin, removing the spines and pedicellariae should be done to minimize the contact with the venom source, and subsequently the management of wounds and poisoning symptoms, as quickly as possible. Conclusion: The venoms of some sea urchins have toxins and bioactive molecules that produce toxicity effects on their

  9. The protein precursors of peptides that affect the mechanics of connective tissue and/or muscle in the echinoderm Apostichopus japonicus.

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    Maurice R Elphick

    Full Text Available Peptides that cause muscle relaxation or contraction or that modulate electrically-induced muscle contraction have been discovered in the sea cucumber Apostichopus japonicus (Phylum Echinodermata; Class Holothuroidea. By analysing transcriptome sequence data, here the protein precursors of six of these myoactive peptides (the SALMFamides Sticho-MFamide-1 and -2, NGIWYamide, stichopin, GN-19 and GLRFA have been identified, providing novel insights on neuropeptide and endocrine-type signalling systems in echinoderms. The A. japonicus SALMFamide precursor comprises eight putative neuropeptides including both L-type and F-type SALMFamides, which contrasts with previous findings from the sea urchin Strongylocentrotus purpuratus where L-type and F-type SALMFamides are encoded by different genes. The NGIWYamide precursor contains five copies of NGIWYamide but, unlike other NG peptide-type neuropeptide precursors in deuterostomian invertebrates, the NGIWYamide precursor does not have a C-terminal neurophysin domain, indicating loss of this character in holothurians. NGIWYamide was originally discovered as a muscle contractant, but it also causes stiffening of mutable connective tissue in the body wall of A. japonicus, whilst holokinins (PLGYMFR and derivative peptides cause softening of the body wall. However, the mechanisms by which these peptides affect the stiffness of body wall connective tissue are unknown. Interestingly, analysis of the A. japonicus transcriptome reveals that the only protein containing the holokinin sequence PLGYMFR is an alpha-5 type collagen. This suggests that proteolysis of collagen may generate peptides (holokinins that affect body wall stiffness in sea cucumbers, providing a novel perspective on mechanisms of mutable connective tissue in echinoderms.

  10. Annotated list of marine alien species in the Mediterranean with records of the worst invasive species

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    A. ZENETOS

    2005-12-01

    Full Text Available This collaborative effort by many specialists across the Mediterranean presents an updated annotated list of alien marine species in the Mediterranean Sea. Alien species have been grouped into six broad categories namely established, casual, questionable, cryptogenic, excluded and invasive, and presented in lists of major ecofunctional/taxonomic groups. The establishment success within each group is provided while the questionable and excluded records are commented in brief. A total of 963 alien species have been reported from the Mediterranean until December 2005, 218 of which have been classified as excluded (23% leaving 745 of the recorded species as valid aliens. Of these 385 (52% are already well established, 262 (35% are casual records, while 98 species (13% remain “questionable” records. The species cited in this work belong mostly to zoobenthos and in particular to Mollusca and Crustacea, while Fish and Phytobenthos are the next two groups which prevail among alien biota in the Mediterranean. The available information depends greatly on the taxonomic group examined. Thus, besides the three groups explicitly addressed in the CIESM atlas series (Fish, Decapoda/Crustacea and Mollusca, which are however updated in the present work, Polychaeta, Phytobenthos, Phytoplankton and Zooplankton are also addressed in this study. Among other zoobenthic taxa sufficiently covered in this study are Echinodermata, Sipuncula, Bryozoa and Ascidiacea. On the contrary, taxa such as Foraminifera, Amphipoda and Isopoda, that are not well studied in the Mediterranean, are insufficiently covered. A gap of knowledge is also noticed in Parasites, which, although ubiquitous and pervasive in marine systems, have been relatively unexplored as to their role in marine invasions. Conclusively the lack of funding purely systematic studies in the region has led to underestimation of the number of aliens in the Mediterranean. Emphasis is put on those species that are

  11. Broad Phylogenetic Occurrence of the Oxygen-Binding Hemerythrins in Bilaterians.

    Science.gov (United States)

    Costa-Paiva, Elisa M; Schrago, Carlos G; Halanych, Kenneth M

    2017-10-01

    Animal tissues need to be properly oxygenated for carrying out catabolic respiration and, as such, natural selection has presumably favored special molecules that can reversibly bind and transport oxygen. Hemoglobins, hemocyanins, and hemerythrins (Hrs) fulfill this role, with Hrs being the least studied. Knowledge of oxygen-binding proteins is crucial for understanding animal physiology. Hr genes are present in the three domains of life, Archaea, Bacteria, and Eukaryota; however, within Animalia, Hrs has been reported only in marine species in six phyla (Annelida, Brachiopoda, Priapulida, Bryozoa, Cnidaria, and Arthropoda). Given this observed Hr distribution, whether all metazoan Hrs share a common origin is circumspect. We investigated Hr diversity and evolution in metazoans, by employing in silico approaches to survey for Hrs from of 120 metazoan transcriptomes and genomes. We found 58 candidate Hr genes actively transcribed in 36 species distributed in 11 animal phyla, with new records in Echinodermata, Hemichordata, Mollusca, Nemertea, Phoronida, and Platyhelminthes. Moreover, we found that "Hrs" reported from Cnidaria and Arthropoda were not consistent with that of other metazoan Hrs. Contrary to previous suggestions that Hr genes were absent in deuterostomes, we find Hr genes present in deuterostomes and were likely present in early bilaterians, but not in nonbilaterian animal lineages. As expected, the Hr gene tree did not mirror metazoan phylogeny, suggesting that Hrs evolutionary history was complex and besides the oxygen carrying capacity, the drivers of Hr evolution may also consist of secondary functional specializations of the proteins, like immunological functions. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  12. Could the acid-base status of Antarctic sea urchins indicate a better-than-expected resilience to near-future ocean acidification?

    Science.gov (United States)

    Collard, Marie; De Ridder, Chantal; David, Bruno; Dehairs, Frank; Dubois, Philippe

    2015-02-01

    Increasing atmospheric carbon dioxide concentration alters the chemistry of the oceans towards more acidic conditions. Polar oceans are particularly affected due to their low temperature, low carbonate content and mixing patterns, for instance upwellings. Calcifying organisms are expected to be highly impacted by the decrease in the oceans' pH and carbonate ions concentration. In particular, sea urchins, members of the phylum Echinodermata, are hypothesized to be at risk due to their high-magnesium calcite skeleton. However, tolerance to ocean acidification in metazoans is first linked to acid-base regulation capacities of the extracellular fluids. No information on this is available to date for Antarctic echinoderms and inference from temperate and tropical studies needs support. In this study, we investigated the acid-base status of 9 species of sea urchins (3 cidaroids, 2 regular euechinoids and 4 irregular echinoids). It appears that Antarctic regular euechinoids seem equipped with similar acid-base regulation systems as tropical and temperate regular euechinoids but could rely on more passive ion transfer systems, minimizing energy requirements. Cidaroids have an acid-base status similar to that of tropical cidaroids. Therefore Antarctic cidaroids will most probably not be affected by decreasing seawater pH, the pH drop linked to ocean acidification being negligible in comparison of the naturally low pH of the coelomic fluid. Irregular echinoids might not suffer from reduced seawater pH if acidosis of the coelomic fluid pH does not occur but more data on their acid-base regulation are needed. Combining these results with the resilience of Antarctic sea urchin larvae strongly suggests that these organisms might not be the expected victims of ocean acidification. However, data on the impact of other global stressors such as temperature and of the combination of the different stressors needs to be acquired to assess the sensitivity of these organisms to global

  13. Trends in the discovery of new marine natural products from invertebrates over the last two decades--where and what are we bioprospecting?

    Science.gov (United States)

    Leal, Miguel Costa; Puga, João; Serôdio, João; Gomes, Newton C M; Calado, Ricardo

    2012-01-01

    It is acknowledged that marine invertebrates produce bioactive natural products that may be useful for developing new drugs. By exploring untapped geographical sources and/or novel groups of organisms one can maximize the search for new marine drugs to treat human diseases. The goal of this paper is to analyse the trends associated with the discovery of new marine natural products from invertebrates (NMNPI) over the last two decades. The analysis considers different taxonomical levels and geographical approaches of bioprospected species. Additionally, this research is also directed to provide new insights into less bioprospected taxa and world regions. In order to gather the information available on NMNPI, the yearly-published reviews of Marine Natural Products covering 1990-2009 were surveyed. Information on source organisms, specifically taxonomical information and collection sites, was assembled together with additional geographical information collected from the articles originally describing the new natural product. Almost 10000 NMNPI were discovered since 1990, with a pronounced increase between decades. Porifera and Cnidaria were the two dominant sources of NMNPI worldwide. The exception was polar regions where Echinodermata dominated. The majority of species that yielded the new natural products belong to only one class of each Porifera and Cnidaria phyla (Demospongiae and Anthozoa, respectively). Increased bioprospecting efforts were observed in the Pacific Ocean, particularly in Asian countries that are associated with the Japan Biodiversity Hotspot and the Kuroshio Current. Although results show comparably less NMNPI from polar regions, the number of new natural products per species is similar to that recorded for other regions. The present study provides information to future bioprospecting efforts addressing previously unexplored taxonomic groups and/or regions. We also highlight how marine invertebrates, which in some cases have no commercial value

  14. Extraocular sensitivity to polarized light in an echinoderm.

    Science.gov (United States)

    Johnsen, S

    1994-10-01

    This study tests the hypotheses that the birefringent calcite and stereom structure of the brittlestar (Ophiuroidea, Echinodermata) endoskeleton polarizes light and that certain brittlestars respond to polarized light. The first hypothesis was tested in Ophioderma brevispinum by examining ossicles from freshly killed specimens under polarized light. This analysis revealed that the lateral arm shields, oral arm shields, arm spines and aboral disk ossicles are dichroic and thus polarize light. The second hypothesis was tested in two orientation experiments under polarized light. The results from the first orientation experiment showed (1) that, under polarized light, animals oriented significantly and unimodally, (2) that, under polarized light with the e-vector perpendicular to that in 1, animals oriented significantly and unimodally to within 18 degrees of the bearing of the animals in 1, and (3) that, under unpolarized light, animals did not orient significantly. The results from the second orientation experiment showed that, under polarized light, animals oriented significantly and unimodally to within 17 degrees of an individual preference previously established under polarized light; but under unpolarized light, animals did not orient significantly to an individual preference established under polarized light. Thus, O. brevispinum orients under polarized, but not unpolarized, light. The unimodal orientation and lack of consistent alignment with the e-vector suggest that polarized light is not used as a directional cue but instead as a signal to sustain oriented behavior. The dichroism of the ossicles of O. brevispinum and the animal's capacity (though eyeless) to discriminate between polarized and unpolarized light suggest that the mechanism of polarization sensitivity may rely on polarizing filters built from the animal's skeleton.

  15. Seasonal monitoring of deep-sea megabenthos in Barkley Canyon cold seep by internet operated vehicle (IOV).

    Science.gov (United States)

    Doya, Carolina; Chatzievangelou, Damianos; Bahamon, Nixon; Purser, Autun; De Leo, Fabio C; Juniper, S Kim; Thomsen, Laurenz; Aguzzi, Jacopo

    2017-01-01

    Knowledge of the processes shaping deep-sea benthic communities at seasonal scales in cold-seep environments is incomplete. Cold seeps within highly dynamic regions, such as submarine canyons, where variable current regimes may occur, are particularly understudied. Novel Internet Operated Vehicles (IOVs), such as tracked crawlers, provide new techniques for investigating these ecosystems over prolonged periods. In this study a benthic crawler connected to the NEPTUNE cabled infrastructure operated by Ocean Networks Canada was used to monitor community changes across 60 m2 of a cold-seep area of the Barkley Canyon, North East Pacific, at ~890 m depth within an Oxygen Minimum Zone (OMZ). Short video-transects were run at 4-h intervals during the first week of successive calendar months, over a 14 month period (February 14th 2013 to April 14th 2014). Within each recorded transect video megafauna abundances were computed and changes in environmental conditions concurrently measured. The responses of fauna to environmental conditions as a proxy of seasonality were assessed through analysis of abundances in a total of 438 video-transects (over 92 h of total footage). 7698 fauna individuals from 6 phyla (Cnidaria, Ctenophora, Arthropoda, Echinodermata, Mollusca, and Chordata) were logged and patterns in abundances of the 7 most abundant taxa (i.e. rockfish Sebastidae, sablefish Anoplopoma fimbria, hagfish Eptatretus stoutii, buccinids (Buccinoidea), undefined small crabs, ctenophores Bolinopsis infundibulum, and Scyphomedusa Poralia rufescens) were identified. Patterns in the reproductive behaviour of the grooved tanner crab (Chionnecetes tanneri) were also indicated. Temporal variations in biodiversity and abundance in megabenthic fauna was significantly influenced by variabilities in flow velocity flow direction (up or down canyon), dissolved oxygen concentration and month of study. Also reported here for the first time are transient mass aggregations of grooved tanner

  16. Seasonal monitoring of deep-sea megabenthos in Barkley Canyon cold seep by internet operated vehicle (IOV.

    Directory of Open Access Journals (Sweden)

    Carolina Doya

    Full Text Available Knowledge of the processes shaping deep-sea benthic communities at seasonal scales in cold-seep environments is incomplete. Cold seeps within highly dynamic regions, such as submarine canyons, where variable current regimes may occur, are particularly understudied. Novel Internet Operated Vehicles (IOVs, such as tracked crawlers, provide new techniques for investigating these ecosystems over prolonged periods. In this study a benthic crawler connected to the NEPTUNE cabled infrastructure operated by Ocean Networks Canada was used to monitor community changes across 60 m2 of a cold-seep area of the Barkley Canyon, North East Pacific, at ~890 m depth within an Oxygen Minimum Zone (OMZ. Short video-transects were run at 4-h intervals during the first week of successive calendar months, over a 14 month period (February 14th 2013 to April 14th 2014. Within each recorded transect video megafauna abundances were computed and changes in environmental conditions concurrently measured. The responses of fauna to environmental conditions as a proxy of seasonality were assessed through analysis of abundances in a total of 438 video-transects (over 92 h of total footage. 7698 fauna individuals from 6 phyla (Cnidaria, Ctenophora, Arthropoda, Echinodermata, Mollusca, and Chordata were logged and patterns in abundances of the 7 most abundant taxa (i.e. rockfish Sebastidae, sablefish Anoplopoma fimbria, hagfish Eptatretus stoutii, buccinids (Buccinoidea, undefined small crabs, ctenophores Bolinopsis infundibulum, and Scyphomedusa Poralia rufescens were identified. Patterns in the reproductive behaviour of the grooved tanner crab (Chionnecetes tanneri were also indicated. Temporal variations in biodiversity and abundance in megabenthic fauna was significantly influenced by variabilities in flow velocity flow direction (up or down canyon, dissolved oxygen concentration and month of study. Also reported here for the first time are transient mass aggregations of

  17. ENSO and sandy beach macrobenthos of the tropical East Pacific: some speculations

    Directory of Open Access Journals (Sweden)

    T. Vanagt

    2006-01-01

    Full Text Available The influence of the ENSO cycle on marine fauna and flora has only recently been given the attention it deserves. The very strong 1997–1998 El Niño and its obvious effects on marine biota was a key point in ENSO research, but unfortunately few quantitative data about the 1997–1998 El Niño itself are available. To gather information about the effect of ENSO on the macrobenthos, we performed a bi-weekly transect monitoring on an Ecuadorian sandy beach in 2000–2001, during the strong La Niña following the 1997–1998 El Niño, and in the normal period of 2002–2004. In this paper, intertidal macrofaunal densities at higher taxonomic level are used to compare a La Niña phase with the 'normal' situation. The few existing documents about El Niño and sandy beach macrobenthos, and scattered data from previous and current research, were used to complete the picture. Total macrobenthos densities were 300% lower during the La Niña phase compared with equal months in the normal phase. Especially Crustacea and Mollusca showed a marked increase in densities towards the normal situation (94% and 341% respectively. Polychaeta and Echinodermata, however, showed higher densities during the La Niña phase (22% and 73% respectively. Two possible explanations are proposed. (1 Low densities during the La Niña could be due to the very strong preceding El Niño, suggesting the populations were still recovering. This hypothesis is supported by previous work done in the south of Peru. This is, however, a cold water system, compared to the Ecuadorian warm water system. (2 The second hypothesis states that a La Niña will have a very severe impact on the intertidal macrofauna of a warm water system like the Ecuadorian coast.

  18. Transcriptomic identification of starfish neuropeptide precursors yields new insights into neuropeptide evolution.

    Science.gov (United States)

    Semmens, Dean C; Mirabeau, Olivier; Moghul, Ismail; Pancholi, Mahesh R; Wurm, Yannick; Elphick, Maurice R

    2016-02-01

    Neuropeptides are evolutionarily ancient mediators of neuronal signalling in nervous systems. With recent advances in genomics/transcriptomics, an increasingly wide range of species has become accessible for molecular analysis. The deuterostomian invertebrates are of particular interest in this regard because they occupy an 'intermediate' position in animal phylogeny, bridging the gap between the well-studied model protostomian invertebrates (e.g. Drosophila melanogaster, Caenorhabditis elegans) and the vertebrates. Here we have identified 40 neuropeptide precursors in the starfish Asterias rubens, a deuterostomian invertebrate from the phylum Echinodermata. Importantly, these include kisspeptin-type and melanin-concentrating hormone-type precursors, which are the first to be discovered in a non-chordate species. Starfish tachykinin-type, somatostatin-type, pigment-dispersing factor-type and corticotropin-releasing hormone-type precursors are the first to be discovered in the echinoderm/ambulacrarian clade of the animal kingdom. Other precursors identified include vasopressin/oxytocin-type, gonadotropin-releasing hormone-type, thyrotropin-releasing hormone-type, calcitonin-type, cholecystokinin/gastrin-type, orexin-type, luqin-type, pedal peptide/orcokinin-type, glycoprotein hormone-type, bursicon-type, relaxin-type and insulin-like growth factor-type precursors. This is the most comprehensive identification of neuropeptide precursor proteins in an echinoderm to date, yielding new insights into the evolution of neuropeptide signalling systems. Furthermore, these data provide a basis for experimental analysis of neuropeptide function in the unique context of the decentralized, pentaradial echinoderm bauplan. © 2016 The Authors.

  19. The response of abyssal organisms to low pH conditions during a series of CO2-release experiments simulating deep-sea carbon sequestration

    Science.gov (United States)

    Barry, J. P.; Buck, K. R.; Lovera, C.; Brewer, P. G.; Seibel, B. A.; Drazen, J. C.; Tamburri, M. N.; Whaling, P. J.; Kuhnz, L.; Pane, E. F.

    2013-08-01

    The effects of low-pH, high-pCO2 conditions on deep-sea organisms were examined during four deep-sea CO2 release experiments simulating deep-ocean C sequestration by the direct injection of CO2 into the deep sea. We examined the survival of common deep-sea, benthic organisms (microbes; macrofauna, dominated by Polychaeta, Nematoda, Crustacea, Mollusca; megafauna, Echinodermata, Mollusca, Pisces) exposed to low-pH waters emanating as a dissolution plume from pools of liquid carbon dioxide released on the seabed during four abyssal CO2-release experiments. Microbial abundance in deep-sea sediments was unchanged in one experiment, but increased under environmental hypercapnia during another, where the microbial assemblage may have benefited indirectly from the negative impact of low-pH conditions on other taxa. Lower abyssal metazoans exhibited low survival rates near CO2 pools. No urchins or holothurians survived during 30-42 days of exposure to episodic, but severe environmental hypercapnia during one experiment (E1; pH reduced by as much as ca. 1.4 units). These large pH reductions also caused 75% mortality for the deep-sea amphipod, Haploops lodo, near CO2 pools. Survival under smaller pH reductions (ΔpH<0.4 units) in other experiments (E2, E3, E5) was higher for all taxa, including echinoderms. Gastropods, cephalopods, and fish were more tolerant than most other taxa. The gastropod Retimohnia sp. and octopus Benthoctopus sp. survived exposure to pH reductions that episodically reached -0.3 pH units. Ninety percent of abyssal zoarcids (Pachycara bulbiceps) survived exposure to pH changes reaching ca. -0.3 pH units during 30-42 day-long experiments.

  20. Macro- and megafauna recorded in the submarine Bari Canyon (southern Adriatic, Mediterranean Sea using different tools

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    G. D'ONGHIA

    2015-01-01

    Full Text Available Macro- and megafauna were recorded in the submarine Bari Canyon (southern Adriatic Sea, Mediterranean Sea during an oceanographic cruise carried out in May-June 2012 and an experimental fishing survey conducted in November 2013. During the former, a total of 20 benthic samples were taken using a Van Veen grab at depths between 268 and 770 m and 4 deployments of a baited lander, for about 43 hours of video records, were carried out at depths between 443 and 788 m. During the latter, 8 longline fishing operations were conducted from 338 down to 612 m. Eighty-five living benthic and benthopelagic species were recorded: 29 Porifera, 1 Cnidaria, 2 Mollusca, 11 Annelida, 1 Arthropoda, 19 Bryozoa, 3 Echinodermata and 19 Chordata. A total of 51 species are new records for the Bari Canyon, 29 new records for the Adriatic Sea. Among the Porifera Cerbaris curvispiculifer is a new addition for the Italian Sponge Fauna. The first certain record of living specimens for the bryozoan Crisia tenella longinodata is reported. A total of 6 Mediterranean endemic species have been identified: 4 Porifera and 2 Annelida. The bathymetric range of some species has been extended. New information acquired for deep sea species confirms their importance in the structure of cold-water coral communities. This study has updated the knowledge on the biodiversity of the Adriatic Sea, as well as of the Bari Canyon in particular, one of the sites designated as “jewels of the Mediterranean” for which urgent conservation measures are needed.

  1. A dataset comprising 141 magnetic resonance imaging scans of 98 extant sea urchin species.

    Science.gov (United States)

    Ziegler, Alexander; Faber, Cornelius; Mueller, Susanne; Nagelmann, Nina; Schröder, Leif

    2014-01-01

    Apart from its application in human diagnostics, magnetic resonance imaging (MRI) can also be used to study the internal anatomy of zoological specimens. As a non-invasive imaging technique, MRI has several advantages, such as rapid data acquisition, output of true three-dimensional imagery, and provision of digital data right from the onset of a study. Of particular importance for comparative zoological studies is the capacity of MRI to conduct high-throughput analyses of multiple specimens. In this study, MRI was applied to systematically document the internal anatomy of 98 representative species of sea urchins (Echinodermata: Echinoidea). The dataset includes raw and derived image data from 141 MRI scans. Most of the whole sea urchin specimens analyzed were obtained from museum collections. The attained scan resolutions permit differentiation of various internal organs, including the digestive tract, reproductive system, coelomic compartments, and lantern musculature. All data deposited in the GigaDB repository can be accessed using open source software. Potential uses of the dataset include interactive exploration of sea urchin anatomy, morphometric and volumetric analyses of internal organs observed in their natural context, as well as correlation of hard and soft tissue structures. The dataset covers a broad taxonomical and morphological spectrum of the Echinoidea, focusing on 'regular' sea urchin taxa. The deposited files significantly expand the amount of morphological data on echinoids that are electronically available. The approach chosen here can be extended to various other vertebrate and invertebrate taxa. We argue that publicly available digital anatomical and morphological data gathered during experiments involving non-invasive imaging techniques constitute one of the prerequisites for future large-scale genotype-phenotype correlations.

  2. Matrotrophy and placentation in invertebrates: a new paradigm.

    Science.gov (United States)

    Ostrovsky, Andrew N; Lidgard, Scott; Gordon, Dennis P; Schwaha, Thomas; Genikhovich, Grigory; Ereskovsky, Alexander V

    2016-08-01

    Matrotrophy, the continuous extra-vitelline supply of nutrients from the parent to the progeny during gestation, is one of the masterpieces of nature, contributing to offspring fitness and often correlated with evolutionary diversification. The most elaborate form of matrotrophy-placentotrophy-is well known for its broad occurrence among vertebrates, but the comparative distribution and structural diversity of matrotrophic expression among invertebrates is wanting. In the first comprehensive analysis of matrotrophy across the animal kingdom, we report that regardless of the degree of expression, it is established or inferred in at least 21 of 34 animal phyla, significantly exceeding previous accounts and changing the old paradigm that these phenomena are infrequent among invertebrates. In 10 phyla, matrotrophy is represented by only one or a few species, whereas in 11 it is either not uncommon or widespread and even pervasive. Among invertebrate phyla, Platyhelminthes, Arthropoda and Bryozoa dominate, with 162, 83 and 53 partly or wholly matrotrophic families, respectively. In comparison, Chordata has more than 220 families that include or consist entirely of matrotrophic species. We analysed the distribution of reproductive patterns among and within invertebrate phyla using recently published molecular phylogenies: matrotrophy has seemingly evolved at least 140 times in all major superclades: Parazoa and Eumetazoa, Radiata and Bilateria, Protostomia and Deuterostomia, Lophotrochozoa and Ecdysozoa. In Cycliophora and some Digenea, it may have evolved twice in the same life cycle. The provisioning of developing young is associated with almost all known types of incubation chambers, with matrotrophic viviparity more widespread (20 phyla) than brooding (10 phyla). In nine phyla, both matrotrophic incubation types are present. Matrotrophy is expressed in five nutritive modes, of which histotrophy and placentotrophy are most prevalent. Oophagy, embryophagy and

  3. Studying the Relative Strengths of Environmental Factors that Influence Echinoderm Body Size Trends

    Science.gov (United States)

    Low, A.; Randhawa, S.; Heim, N. A.; Payne, J.

    2013-12-01

    Body size is often a useful metric in observing how a clade responds to environmental changes. Previous research has uncovered how environmental factors such as carbon dioxide and oxygen levels influence body size evolution. However, we wanted to look into how these natural factors interact and which factors seem to have a stronger relative influence on echinoderm body size. We analyzed carbon dioxide levels, a proxy for paleotemperature, oxygen levels, and sea level. Our research process involved measuring and calculating the volume of Phanerozoic echinoderm fossils recorded in the Treatise on Invertebrate Paleontology, plotting their mean volumes over various natural factors, and using statistical tools such as correlation tests and the PaleoTS statistical analysis software to compare the relative strengths of these factors. Furthermore, we divided our data into the following three subsets to uncover more specific relationships: 1) A set that included all data of the phylum Echinodermata 2) A set that focused on the two classes with the most recorded data, Echinoidea and Crinoidea 3) A set that focused on the crinoid specimens that originated in the Paleozoic and in the post-Paleozoic. In the first subset, echinoderms had the strongest correlation with carbon dioxide, a proxy for temperature, and possessed a weaker correlation with oxygen. In the second subset, we discovered that the echinoid data also possessed a strong correlation with carbon dioxide and a weaker correlation with oxygen. For crinoids, we found that the class as a whole showed no strong correlation with any measured environmental factors. However, when we divided the crinoids based on age, we found that both Paleozoic and post-Paleozoic crinoids individually correlated strongly with sea level. However, some uncertainty with this correlation arose as the comparison of the environmental correlate models suggested that an unbiased random walk was the best fit for the data. This stands as a sharp

  4. SALMFamide salmagundi: the biology of a neuropeptide family in echinoderms.

    Science.gov (United States)

    Elphick, Maurice R

    2014-09-01

    The SALMFamides are a family of neuropeptides that occur in species belonging to the phylum Echinodermata. The prototypes for this neuropeptide family (S1 and S2) were discovered in starfish but subsequently SALMFamides were identified in other echinoderms. There are two types of SALMFamides: L-type, which have the C-terminal motif SxLxFamide, and F-type, which have the C-terminal motif SxFxFamide. They are derived from two types of precursor proteins: an L-type SALMFamide precursor, which comprises only L-type or L-type-like SALMFamides and an F-type SALMFamide precursor, which contains several F-type or F-type-like SALMFamides and, typically, one or more L-type SALMFamides. Thus, SALMFamides occur as heterogeneous mixtures of neuropeptides - a SALMFamide salmagundi. SALMFamides are produced by distinct populations of neurons in echinoderm larval and adult nervous systems and are present in the innervation of neuromuscular organs. Both L-type and F-type SALMFamides cause muscle relaxation in echinoderms and, for example, in starfish this effect of SALMFamides may mediate neural control of cardiac stomach eversion in species that feed extra-orally (e.g., Asterias rubens). The SALMFamide S1 also causes inhibition of neural release of a relaxin-like gonadotropin in the starfish Asterina pectinifera. An important issue that remains to be resolved are the relationships of SALMFamides with neuropeptides that have been identified in other phyla. However, it has been noted that the C-terminal SxLxFamide motif of L-type SALMFamides is a feature of some members of a bilaterian neuropeptide family that includes gonadotropin-inhibitory hormone (GnIH) in vertebrates and SIFamide-type neuropeptides in protostomes. Similarly, the C-terminal FxFamide motif of F-type SALMFamides is a feature of vertebrate QRFP (26RFa)-type neuropeptides. These sequence similarities may provide a basis for molecular identification of receptors that mediate effects of SALMFamides. Furthermore

  5. Local Ecological Knowledge Indicates Temporal Trends of Benthic Invertebrates Species of the Adriatic Sea

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    Azzurra Bastari

    2017-05-01

    Full Text Available In the Adriatic Sea, shifts in benthic community structure have been attributed to multiple stressors, from the effects of climate change to the impacts of commercial fishing. Some fishing practices, such as bottom trawling, have caused a widespread decline in exploited fish stocks. Bottom trawling is also expected to have negative impacts on benthic habitats, usually structured by and hosting a large array of invertebrate species, which provide important ecological services to fish and commercial invertebrate stocks. However, in contrast to commercial species for which long-term time series of the abundance exist, data on these habitat-forming invertebrates are scarce, as they are usually caught as bycatch and discarded. Therefore, there is great uncertainty about their long-term trends, and if these populations are stable or declining. Here we used interview surveys conducted with bottom-trawling fishers of the central Adriatic Sea to gather local ecological knowledge on megabenthos abundance occurring in their fishing domain, as an alternative source of information to conventional fisheries data. We interviewed 44 fishers, from the most important ports of the Marche region of Italy, to understand how megabenthic species have changed in abundance within the area since the 1980s. Specifically, we asked fishers to provide qualitative abundance scores for 18 invertebrate species in five phyla (Porifera, Cnidaria, Bryozoa, Mollusca, and Echinodermata based on their recollection of these species' presence in bycatch. We stratified responses in homogeneous temporal periods and geographic sectors of the study area, and analyzed their response with mixed effect ordered logistic regression models in order to evaluate spatiotemporal changes in the perceived abundance of each species. Our analysis suggests that the abundance of the sponge Geodia cydonium, the molluscs Pecten jacobaeus, Atrina fragilis, Neopycnodonte cochlear, and the group of

  6. Proximate composition of marine invertebrates from tropical coastal waters, with emphasis on the relationship between nitrogen and protein contents

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    Graciela S Diniz

    2014-05-01

    Full Text Available The chemical profiles of Desmapsamma anchorata, Hymeniacidon heliophila (Porifera, Bunodosoma caissarum, Renilla muelleri (Cnidaria, Aplysia brasiliana, Eledone massyae, Isognomon bicolor (Mollusca, Echinaster brasiliensis, Echinometra lucunter, Holothuria grisea, Lytechinus variegatus (Echinodermata, and Phallusia nigra (Chordata were determined. Hydrosoluble protein was the most abundant class of substances for all species, except for the ascidian Phallusia nigra, in which the carbohydrate content was higher. The percentages of hydrosoluble protein (dry weight, dw varied widely among the invertebrates, ranging from 5.88% (R. muelleri to 47.6% (Eledone massyae of the dw .The carbohydrate content fluctuated from 1.3% (R. muelleri to 18.4% (Aplysia brasiliana of the dw. For most of the species, lipid was the second most abundant class of substances, varying from 2.8% (R. muelleri to 25.3% (Echinaster brasiliensis of the dw. Wide variations were also found for the invertebrates nitrogen content, with the lowest value recorded in the cnidarian R. muelleri (2.02% of the dw and the highest in the molluscan E. massyae (12.7% of the dw. The phosphorus content of the dw varyed from 0.24% (R. muelleri to 1.16% (E. massyae. The amino acid composition varied largely among the species, but for most of the species glycine, arginine, glutamic acid, and aspartic acid were the most abundant amino acids, with histidine and tyrosine among the less abundant amino acids. The actual content of total protein in the samples was calculated by the sum of amino acid residues, establishing dw values that fluctuated from 11.1% (R. muelleri to 66.7% (E. massyae. The proteinaceous nitrogen content was high in all species, with an average value of 97.3% of the total nitrogen. From data of total amino acid residues and total nitrogen, specific nitrogen-to-protein conversion factors were calculated for each species. The nitrogen-to-protein conversion factors ranged from 5.10 to

  7. Localization of neuropeptide gene expression in larvae of an echinoderm, the starfish Asterias rubens

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    Tatiana D Mayorova

    2016-12-01

    Full Text Available Neuropeptides are an ancient class of neuronal signaling molecules that regulate a variety of physiological and behavioral processes in animals. The life cycle of many animals includes a larval stage(s that precedes metamorphic transition to a reproductively active adult stage but, with the exception of Drosophila melanogaster and other insects, research on neuropeptide signaling has hitherto largely focused on adult animals. However, recent advances in genome/transcriptome sequencing have facilitated investigation of neuropeptide expression/function in the larvae of protostomian (e.g. the annelid Platynereis dumerilii and deuterostomian (e.g. the urochordate Ciona intestinalis invertebrates. Accordingly, here we report the first multi-gene investigation of larval neuropeptide precursor expression in a species belonging to the phylum Echinodermata - the starfish Asterias rubens. Whole-mount mRNA in situ hybridization was used to visualize in bipinnaria and brachiolaria stage larvae the expression of eight neuropeptide precursors: L-type SALMFamide (S1, F-type SALMFamide (S2, vasopressin/oxytocin-type, NGFFYamide, thyrotropin-releasing hormone-type, gonadotropin-releasing hormone-type, calcitonin-type and corticotropin-releasing hormone-type. Expression of only three of the precursors (S1, S2, NGFFYamide was observed in bipinnaria larvae but by the brachiolaria stage expression of all eight precursors was detected. An evolutionarily conserved feature of larval nervous systems is the apical organ and in starfish larvae this comprises the bilaterally symmetrical lateral ganglia, but only the S1 and S2 precursors were found to be expressed in these ganglia. A prominent feature of brachiolaria larvae is the attachment complex, comprising the brachia and adhesive disk, which mediates larval attachment to a substratum prior to metamorphosis. Interestingly, all of the neuropeptide precursors examined here are expressed in the attachment complex, with

  8. PCR survey of 50 introns in animals: cross-amplification of homologous EPIC loci in eight non-bilaterian, protostome and deuterostome phyla.

    Science.gov (United States)

    Gérard, K; Guilloton, E; Arnaud-Haond, S; Aurelle, D; Bastrop, R; Chevaldonné, P; Derycke, S; Hanel, R; Lapègue, S; Lejeusne, C; Mousset, S; Ramšak, A; Remerie, T; Viard, F; Féral, J-P; Chenuil, A

    2013-12-01

    Exon Primed Intron Crossing (EPIC) markers provide molecular tools that are susceptible to be variable within species while remaining amplifiable by PCR using potentially universal primers. In this study we tested the possibility of obtaining PCR products from 50 EPIC markers on 23 species belonging to seven different phyla (Porifera, Cnidaria, Arthropoda, Nematoda, Mollusca, Annelida, Echinodermata) using 70 new primer pairs. A previous study had identified and tested those loci in a dozen species, including another phylum, Urochordata (Chenuil et al., 2010). Results were contrasted among species. The best results were achieved with the oyster (Mollusca) where 28 loci provided amplicons susceptible to contain an intron according to their size. This was however not the case with the other mollusk Crepidula fornicata, which seems to have undergone a reduction in intron number or intron size. In the Porifera, 13 loci appeared susceptible to contain an intron, a surprisingly high number for this phylum considering its phylogenetic distance with genomic data used to design the primers. For two cnidarian species, numerous loci (24) were obtained. Ecdysozoan phyla (arthropods and nematodes) proved less successful than others as expected considering reports of their rapid rate of genome evolution and the worst results were obtained for several arthropods. Some general patterns among phyla arose, and we discuss how the results of this EPIC survey may give new insights into genome evolution of the study species. This work confirms that this set of EPIC loci provides an easy-to-use toolbox to identify genetic markers potentially useful for population genetics, phylogeography or phylogenetic studies for a large panel of metazoan species. We then argue that obtaining diploid sequence genotypes for these loci became simple and affordable owing to Next-Generation Sequencing development. Species surveyed in this study belong to several genera (Acanthaster, Alvinocaris, Aplysina

  9. Distribution of creatine, guanidinoacetate and the enzymes for their biosynthesis in the animal kingdom. Implications for phylogeny.

    Science.gov (United States)

    Van Pilsum, J F; Stephens, G C; Taylor, D

    1972-01-01

    1. The distribution of creatine and the creatine-synthesizing enzymes in the animal kingdom has been investigated. Creatine was found in tissues of all vertebrates examined, and in various invertebrates from phyla Annelida, Echinodermata, Hemichordata and Chordata, subphylum Cephalochordata. The activities of the creatine-synthesizing enzymes, arginine-glycine transamidinase and guanidinoacetate methylpherase, were not detected in the hagfish or in any of the invertebrates, including those in which creatine was found, with the exception that transamidinase activities were detected in the amphioxus and salt water clam; however, these activities are considered to be artifacts for reasons mentioned in the text. Additional evidence that the hagfish and various creatine-containing invertebrates could not synthesize creatine was the observation that these animals did not convert one or the other of the likely precursors of creatine (arginine and glycine) into creatine, in vivo. Further, the inability of these animals to synthesize creatine is correlated with the observations that all animals tested were able to abstract creatine from their aqueous environment. 2. The activities of the creatine-synthesizing enzymes were detected in the sea lamprey and in all but a few of the other vertebrates examined. Neither activity could be detected in the sharks and rays (cartilaginous fish), buffalo fish (bony fish) or the snapping turtle. Transamidinase or guanidinoacetate methylpherase activity could not be found in the salamander or garter snake, respectively. 3. The results obtained with the lamprey are in direct contrast with those obtained with the hagfish (both subphylum Agnatha, class Cyclostomata). The lamprey had the ability to synthesize creatine and did not abstract creatine from lake water. The hagfish did not have any apparent ability to synthesize creatine and did abstract creatine from sea water. The present report thus supports the theory that the myxinoid (hagfish

  10. Marine biodiversity of Aotearoa New Zealand.

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    Dennis P Gordon

    Full Text Available The marine-biodiversity assessment of New Zealand (Aotearoa as known to Māori is confined to the 200 nautical-mile boundary of the Exclusive Economic Zone, which, at 4.2 million km(2, is one of the largest in the world. It spans 30 degrees of latitude and includes a high diversity of seafloor relief, including a trench 10 km deep. Much of this region remains unexplored biologically, especially the 50% of the EEZ deeper than 2,000 m. Knowledge of the marine biota is based on more than 200 years of marine exploration in the region. The major oceanographic data repository is the National Institute of Water and Atmospheric Research (NIWA, which is involved in several Census of Marine Life field projects and is the location of the Southwestern Pacific Regional OBIS Node; NIWA is also data manager and custodian for fisheries research data owned by the Ministry of Fisheries. Related data sources cover alien species, environmental measures, and historical information. Museum collections in New Zealand hold more than 800,000 registered lots representing several million specimens. During the past decade, 220 taxonomic specialists (85 marine from 18 countries have been engaged in a project to review New Zealand's entire biodiversity. The above-mentioned marine information sources, published literature, and reports were scrutinized to give the results summarized here for the first time (current to 2010, including data on endemism and invasive species. There are 17,135 living species in the EEZ. This diversity includes 4,315 known undescribed species in collections. Species diversity for the most intensively studied phylum-level taxa (Porifera, Cnidaria, Mollusca, Brachiopoda, Bryozoa, Kinorhyncha, Echinodermata, Chordata is more or less equivalent to that in the ERMS (European Register of Marine Species region, which is 5.5 times larger in area than the New Zealand EEZ. The implication is that, when all other New Zealand phyla are equally well studied

  11. Identification of a novel starfish neuropeptide that acts as a muscle relaxant.

    Science.gov (United States)

    Kim, Chan-Hee; Kim, Eun Jung; Go, Hye-Jin; Oh, Hye Young; Lin, Ming; Elphick, Maurice R; Park, Nam Gyu

    2016-04-01

    peptide (SMP), a novel member of the PP/OK-type neuropeptide identified in the starfish Patiria pectinifera (phylum Echinodermata). SMP is the first PP/OK-type neuropeptide to be functionally characterised in a deuterostome. © 2016 The Authors. Journal of Neurochemistry published by John Wiley & Sons Ltd on behalf of International Society for Neurochemistry.

  12. Güneydoğu Marmara'da Algarna ile Karides Avcılığında Av Kompozisyonu ve Hedef Dışı Av.

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    Yusuf Kenan Bayhan

    2015-12-01

    Full Text Available Bir yıl süre ile yürütülen bu çalışma, Kasım 2000 - Ekim 2001 tarihleri arasında Güneydoğu Marmara’da gerçekleştirilmiştir. Çalışmada, algarna ile avcılıkta hedef tür olan derin su pembe karidesi (Parapenaeus longirostris’in ağırlık ve sayısal miktarları ile bunun dışındaki av kompozisyonu, türlerin boy dağılımları ve toplam av içerisindeki sayısal oranları araştırılmıştır. Yapılan çekimler sonucunda, toplam avın sayısal olarak % 64.5’ni hedef tür olan Parapenaeus longirostris, % 35.5’ini hedef dışı av oluşturmuştur. 50 türün bulunduğu hedef dışı avın % 17.16’sını Kemikli balıklar (Osteichthyes, % 8.58’ini Kabuklular (Crustacea-Decapoda, % 4.94’ünü Derisi Dikenliler (Echinodermata, % 2.53’ünü Yumuşakçalar (Mollusca, % 2.14’ünü Cnidaria ve % 0.13’ünü kıkırdaklı balıklar (Chondrichthyes oluşturmuş, toplam av içerisinde Parapenaeus longirostris’in dışında sayısal olarak en çok yakalanan türlerin başında ise Kaya balığı, Mezgit, Kancaağız pisi, Yengeç, Deniz yıldızı ve Deniz hıyarı’nın geldiği belirlenmiştir

  13. Marine biodiversity of Aotearoa New Zealand.

    Science.gov (United States)

    Gordon, Dennis P; Beaumont, Jennifer; MacDiarmid, Alison; Robertson, Donald A; Ahyong, Shane T

    2010-08-02

    The marine-biodiversity assessment of New Zealand (Aotearoa as known to Māori) is confined to the 200 nautical-mile boundary of the Exclusive Economic Zone, which, at 4.2 million km(2), is one of the largest in the world. It spans 30 degrees of latitude and includes a high diversity of seafloor relief, including a trench 10 km deep. Much of this region remains unexplored biologically, especially the 50% of the EEZ deeper than 2,000 m. Knowledge of the marine biota is based on more than 200 years of marine exploration in the region. The major oceanographic data repository is the National Institute of Water and Atmospheric Research (NIWA), which is involved in several Census of Marine Life field projects and is the location of the Southwestern Pacific Regional OBIS Node; NIWA is also data manager and custodian for fisheries research data owned by the Ministry of Fisheries. Related data sources cover alien species, environmental measures, and historical information. Museum collections in New Zealand hold more than 800,000 registered lots representing several million specimens. During the past decade, 220 taxonomic specialists (85 marine) from 18 countries have been engaged in a project to review New Zealand's entire biodiversity. The above-mentioned marine information sources, published literature, and reports were scrutinized to give the results summarized here for the first time (current to 2010), including data on endemism and invasive species. There are 17,135 living species in the EEZ. This diversity includes 4,315 known undescribed species in collections. Species diversity for the most intensively studied phylum-level taxa (Porifera, Cnidaria, Mollusca, Brachiopoda, Bryozoa, Kinorhyncha, Echinodermata, Chordata) is more or less equivalent to that in the ERMS (European Register of Marine Species) region, which is 5.5 times larger in area than the New Zealand EEZ. The implication is that, when all other New Zealand phyla are equally well studied, total marine

  14. The enigmatic mitochondrial genome of Rhabdopleura compacta (Pterobranchia reveals insights into selection of an efficient tRNA system and supports monophyly of Ambulacraria

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    Stadler Peter F

    2011-05-01

    Full Text Available Abstract Background The Hemichordata comprises solitary-living Enteropneusta and colonial-living Pterobranchia, sharing morphological features with both Chordata and Echinodermata. Despite their key role for understanding deuterostome evolution, hemichordate phylogeny is controversial and only few molecular data are available for phylogenetic analysis. Furthermore, mitochondrial sequences are completely lacking for pterobranchs. Therefore, we determined and analyzed the complete mitochondrial genome of the pterobranch Rhabdopleura compacta to elucidate deuterostome evolution. Thereby, we also gained important insights in mitochondrial tRNA evolution. Results The mitochondrial DNA of Rhabdopleura compacta corresponds in size and gene content to typical mitochondrial genomes of metazoans, but shows the strongest known strand-specific mutational bias in the nucleotide composition among deuterostomes with a very GT-rich main-coding strand. The order of the protein-coding genes in R. compacta is similar to that of the deuterostome ground pattern. However, the protein-coding genes have been highly affected by a strand-specific mutational pressure showing unusual codon frequency and amino acid composition. This composition caused extremely long branches in phylogenetic analyses. The unusual codon frequency points to a selection pressure on the tRNA translation system to codon-anticodon sequences of highest versatility instead of showing adaptations in anticodon sequences to the most frequent codons. Furthermore, an assignment of the codon AGG to Lysine has been detected in the mitochondrial genome of R. compacta, which is otherwise observed only in the mitogenomes of some arthropods. The genomes of these arthropods do not have such a strong strand-specific bias as found in R. compacta but possess an identical mutation in the anticodon sequence of the tRNALys. Conclusion A strong reversed asymmetrical mutational constraint in the mitochondrial genome of

  15. Asteroidea, Echinoidea y Holothuroidea en fondos someros de la Bahía de Loreto, Baja California Sur, México

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    Oscar Holguin Quiñones

    2000-12-01

    Full Text Available Para evaluar distribución, abundancia y densidades de erizos, estrellas y pepinos de mar en la Bahía de Loreto se empleó un transecto de 50 metros, por duplicado, con un margen de observación de 2.5 m a cada lado del mismo por estación y fecha de muestreo. Se observaron mayores abundancias y densidades en la clase Echinoidea: Echinometra vanbrunti (94.1+ 52.9 ind, 0.25 ind/m², Centrostephanus coronatus (38.15+9.15 ind, 0.06 ind/m², Tripneustes depressus (28.68 + 6.86 ind, 0.039 ind/ m², Eucidaris thouarsii (10.66+3.37 ind, 0.025 ind/m² y Diadema mexicanum (11.75+4.92 ind, 0.023 ind/ m²; y para la clase Asteroidea: Phataria unifascialis, Mithrodia bradleyi y Acanthaster planci. Por el número de especies domina Asteroidea con 12, le siguen Echinoidea con 10 y Holothuroidea con 4.To evaluate echinoderm distribution, abundance and density a double 50 m transect, with a side observation range of 2.5 m was used at each of 11 stations (bimonthly samplings, Aug. 1997-Febr. 1998. In Bahía de Loreto the Phylum Echinodermata consists of 26 taxa. The greatest mean abundance by transect and mean densities in order of importance for Echinoidea were: Echinometra vanbrunti (94.1+ 52.9 ind, 0.25 ind/m², Centrostephanus coronatus (38.15. + 9.15 ind, 0.06 ind/m², Tripneustes depressus (28.68 + 6.86 ind, 0.039 ind/ m², Eucidaris thouarsii (10.66 + 3.37 ind, 0.025 ind/m² and Diadema mexicanum (11.75 + 4.92 ind, 0.023 ind/ m²; for Asteroidea were: Phataria unifascialis, Mithrodia bradleyi and Acanthaster planci. Asteroidea was the dominant class with 12 species, followed by Echinoidea with ten and Holothuroidea was represented by four species.

  16. STRUKTUR KOMUNITAS PLANKTON DAN KONDISI LINGKUNGAN PERAIRAN DI TELUK JAKARTA

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    Adriani Sri Nastiti

    2016-03-01

    Full Text Available Fitoplankton dan zooplankton merupakan pakan alami bagi biota laut termasuk ikan. Tujuan penelitian adalah mengetahui struktur komunitas fitoplankton dan zooplankton serta kondisi lingkungan perairan di Teluk Jakarta. Penelitian dilakukan pada bulan April, Juni, Agustus dan Oktober 2009, pengamatan di 5 stasiun TJ1, TJ2, TJ3, TJ4 dan TJ5. Parameter yang di ukur adalah: kelimpahan fitoplankton dan zooplankton, suhu air, kecerahan, oksigen terlarut, pH, salinitas,. Hasil penelitian menunjukkan bahwa fitoplankton yang ditemukan 5 kelas meliputi: Cyanophyceae (6 spesies, Chlorophyceae (4 spesies, Bacillariophyceae (37 spesies, Dinophyceae (14 spesies dan Euglenophyceae (1 species. Zooplankton yang ditemukan 10 kelas meliputi : Crustacea (16 spesies, Holothuroidea (3 spesies, Ciliata (5 spesies, Sagittoidea (2 spesies, Sarcodina (3 spesies, Rotatoria (4 spesies, Echinodermata (1 spesies, Polychaeta (1 spesies, Urochordata (1 spesies dan Hydrozoa (1 spesies. Kelimpahan fitoplankton berkisar antara 1.587.086 - 3.799.799 sel/l. Kelimpahan zooplankton berkisar antara 922.010 - 3.834.261ind/l. Indeks keanekaragaman (=H  fitoplankton berkisar antara 1,74 – 3,64;indeks dominansi (=D berkisar antara 0,04-0,40 dan indeks keseragaman (=E berkisar antara 0,08-0,34. Indeks  biologi zooplankton menunjukkan nilai (=H berkisar antara 0,22-3,70; nilai  (=D berkisar antara 0,18-0,79; dan nilai (=E berkisar antara 0,01-0,37.  Suhu air berkisar  antara 29,5-31,6oC, pH berkisar antara 4,96-7,38 dan salinitas berkisar antara 12,0-31,5 o/oo. Teluk Jakarta diindikasikan mengalami tekanan lingkungan sehingga hanya beberapa spesies plankton mampu beradaptasi, yaitu dari kelas Bacillariophyceae (Chaetoceros sp dan Crustaceae (Calanus sp dan Acartia sp.  Phytoplankton and zooplankton is a natural food for other marine life including fish. Growth and development are supported by condition of aquatic environment. The research objective was to determine the community

  17. Benthic communities associated to Thalassia testudinum (Hydrocharitaceae at three localities of Morrocoy National Park, Venezuela

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    Ricardo Bitter - Soto

    1999-09-01

    Full Text Available The benthic community associated with the turtlegrass Thalassia testudinum beds was analized at three localities of Morrocoy National Park, Venezuela. The localities were selected according to their exposure to the open sea : A (protected, B (intermediate and C (exposed. At each locality, a 20 x 20 m area was randomly chosen, delimited and divided into 400 1x1 m quadrats. Inside each, ten randomly selected quadrats/month were sampled during 13 consecutive months. At each site all macroinvertebrates and several physical variables were recorded, as well as leaf and rhizome biomass of T. testudinum. All parameters had a step- wise gradient from A through C: organic matter, carbon nitrogen, oxygen, salinity and temperature gradient was: ABC. Percentages of sand, silt and clay showed an inverse gradient; ASe analizó la comunidad bentónica asociada a Thalassia testudinum y su relación con algunos parámetros bióticos y abióticos, en tres localidades del Parque Nacional Morrocoy, Falcón-Venezuela; éstas fueron seleccionadas de acuerdo al grado de exposición al mar abierto: A(protegída, B (intermedia y C (expuesta. En cada localidad se demarcó un área de 20 x 20m, se muestrearon aleatoriamente 10cuadrantes/mes, (130 cuadrantes/localidad. Se efectuaron registros de oxígeno disuelto, salinidad, temperatura, porcentajes de materia orgánica, carbono y nitrógeno, textura del sedimento, biomasa foliar y de rizoma de T. testudinum. Todos los parámetros analizados presentaron un gradiente escalonado. Materia Orgánica, Carbono y Nitrógeno, Oxígeno disuelto, Salinidad y Temperatura presentaron el gradiente: ABC. Los porcentages de Arena, Limo y Arcilla presentaron un gradiente inverso. El patrón en la Diversidad, Equidad y Dominancia fue: BCA. La fauna colectada estuvo compuesta por los grupos: Coelenterata (Anthozoa, Polichaeta, Sipuncula, Molusca, Crustacea y Echinodermata. Se identificaron 15 especies de moluscos (gastrópodos y bivalvos, (3

  18. Sea urchins, their predators and prey in SW Portugal

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    Nuno Mamede

    2014-06-01

    Full Text Available Sea urchins play a key role structuring benthic communities of rocky shores through an intense herbivory. The most abundant sea urchin species on shallow rocky subtidal habitats of the SW coast of Portugal is Paracentrotus lividus (Echinodermata: Echinoidea. It is considered a key species in various locations throughout its geographical distribution by affecting the structure of macroalgae communities and may cause the abrupt transformation of habitats dominated by foliose algae to habitats dominated by encrusting algae - the urchin barrens. The removal of P. lividus predators by recreational and commercial fishing is considered a major cause of this phenomenon by affecting the trophic relationships between predators, sea urchins and algae communities. Marine protected areas (MPAs usually lead to the recovery of important predator species that control sea urchin populations and restore habitats dominated by foliose macroalgae. Therefore, MPAs provide a good opportunity to test cascading effects and indirect impacts of fishing at the ecosystem level. The ecological role of P. lividus was studied on rocky subtidal habitats of the SW coast of Portugal (Alentejo considering three trophic levels: population of P. lividus, their predators (fish and shellfish and their prey (macroalgae communities. Several studies were conducted: (1 a non-destructive observational study on the abundance and distribution patterns of P. lividus, their predators and preys, comparing areas with different protection; (2 a manipulative in situ study with cages to assess the role of P. lividus as an herbivore and the influence of predation; (3 a descriptive study of P. lividus predators based on underwater filming; (4 and a study of human perception on these trophic relationships and other issues on sea urchin ecology and fishery, based on surveys made to fishermen and divers. Subtidal studies were performed with SCUBA diving at 3-12 m deep. Results indicate that in the

  19. Benthic foraminiferal fauna as a tool to indicate the Toarcian Oceanic Anoxic Event in homogeneous Ammonitico Rosso series of Bakonycsernye (Transdanubian Hungary)

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    Zsiborás, Gábor; Görög, Ágnes

    2017-04-01

    In the last decades, since the Toarcian Oceanic Anoxic Event (T-OAE, ˜182 Ma) recognized, several studies was dealing with the effect of it on the foraminiferal faunas from black shales and marls of the epicontinental region. Only a few work was made from the Tethyan oceanic basin region (Monaco et al., 1994; Nini et al., 1995; Pettinelli et al., 1997) characterized by occurrence of black shales between the "Lower Posidonia Shale" and the Ammonitico Rosso. However, the black shale is absent in some Tehyan sections substituted by red or grey marls. Only Reolid et al. (2015) focused on foraminifera from this kind of successions, from the Betic Cordillera, where the T-OAE was not detected. From the section of Tű zkövesárok of Bakonycsernye, Transdanubian Central Range, Hungary, Monostori in Galácz et al. (2008) based on the Bairdidae dominated ostracod fauna indicated suboxic environment at the Pliensbachian/Toarcian boundary. Thus the aim of our study was to give paleoecological interpretation of the foraminiferal fauna of this 2 m thick Ammonitico Rosso sequence. Foraminifers were extracted from six red nodular, slightly argillaceous limestone (Tű zkövesárok Limestone) samples from the Pliensbachian part (Emaciatum Zone) and one sample from the Toarcian part (Tenuicostatum Zone) which begins with a hardground and following by red marl (Kisgerecse Marl). The washing residues of the lower four samples contains foraminifers, sponge spicules, radiolarians and echinodermata parts (crinoids and holothurians). The upper two Pliensbachian samples include more foraminifers, however, other groups are absent. The Toarcian sample contains crinoids and less foraminifers (30%). Overall 68 taxa were identified, 54 on species, 14 on generic level. The most of the specimens have calcitic tests, in the Pliensbachian, agglutinated forms are 7-24% of the fauna, however, they are absent in the Toarcian. Upwards to the Pliensbachian/Toarcian boundary, the diversity of the fauna

  20. Programa de Pós-Graduação em Geologia - Dissertações Defendidas 1998 - Mestrado - Instituto de Geociências - Universidade Federal do Rio de Janeiro

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    1998-01-01

    revisão sistemática dos equinóides regulares (ECHINODERMATA-ECHINOIDEA procedentes das rochas da Formação Pirabas (Oligo-Mioceno, Pará, Brasil. São redescritos Phyllacanthus priscus Brito & Ramirez, Histocidaris sp. e Prionocidaris sp., e são assinaladas, pela primeira vez, radíolos em “forma de leque” no Cenozóico das Américas atribuídos ao gênero “Cidaris”, e a primeira carapaça de um euequinóide regular, Psammechinus sp., em rochas do Cenozóico do Brasil. As análises tafonômica e paleoecológica preliminares sugerem uma deposição dos sedimentos da Formação Pirabas em mar de águas quentes e tranqüilas, sujeito a ações de tempestades, com condições excepcionais de fossilização localizadas. A nível filogenético é reafirmada a estreita relação dos equinóides regulares assinalados nas rochas da Formação Pirabas, com formas similares existentes na Província Faunística Caribeana durante o Cenozóico. Nome: Margareth de Toledo Conte Zulian Título: Um Estudo sobre Infiltração de Águas Pluviais em Fraturas Naturais na Porção Oeste da Serra da Carioca, Município do Rio de Janeiro Orientador: Eurípedes do Amaral Vargas Jr. Resumo: Através do mapeamento de duas áreas-piloto representativas da Serra da Carioca, o Morro da Formiga (vertente noroeste e a Ponta do Marisco (vertente sudoeste, verificou-se que a serra é seccionada por um sistema de fraturas, o qual apresenta duas famílias principais de direções NW-SE e NE-SW, com mergulhos subverticais. Famílias secundárias de direções aproximadas E-W e N-S, com mergulhos subverticais, NW-SE, com baixos ângulos de mergulho para SW e ainda E-W, com baixos ângulos de mergulho para S também são observadas e caracterizadas como juntas de alívio. Em todas as famílias foram estudadas as propriedades geométricas (orientação, persistência, espaçamento, a percolação de fluxo, as aberturas e o tipo de preenchimento, com o objetivo de entender o papel das fraturas na