Sample records for scaphopod graptacme eborea
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Energy Technology Data Exchange (ETDEWEB)
Boore, Jeffrey L.; Medina, Monica; Rosenberg, Lewis A.
2004-01-31
We have determined the complete sequence of the mitochondrial genome of the scaphopod mollusk Graptacme eborea (Conrad, 1846) (14,492 nts) and completed the sequence of the mitochondrial genome of the bivalve mollusk Mytilus edulis Linnaeus, 1758 (16,740 nts). (The name Graptacme eborea is a revision of the species formerly known as Dentalium eboreum.) G. eborea mtDNA contains the 37 genes that are typically found and has the genes divided about evenly between the two strands, but M. edulis contains an extra trnM and is missing atp8, and has all genes on the same strand. Each has a highly rearranged gene order relative to each other and to all other studied mtDNAs. G. eborea mtDNA has almost no strand skew, but the coding strand of M. edulis mtDNA is very rich in G and T. This is reflected in differential codon usage patterns and even in amino acid compositions. G. eborea mtDNA has fewer non-coding nucleotides than any other mtDNA studied to date, with the largest non-coding region being only 24 nt long. Phylogenetic analysis using 2,420 aligned amino acid positions of concatenated proteins weakly supports an association of the scaphopod with gastropods to the exclusion of Bivalvia, Cephalopoda, and Polyplacophora, but is generally unable to convincingly resolve the relationships among major groups of the Lophotrochozoa, in contrast to the good resolution seen for several other major metazoan groups.
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Årpád, Dàvid
1992-01-01
Trace fossils, found on shells of gastropods, bivalves and scaphopods from Molluscan Clay exposures (Oligocene, Egerian) at Eger (Wind brickyard) and Novaj (Nyárjas Hill) (NE Hungary), were studied. The relative abundance of different types of borings, traces of bioerosion and palaeopathological
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Marine shell hoard from the Late Neolithic site of Čepin-Ovčara (Slavonia, Croatia
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Boban Tripković
2016-12-01
Full Text Available The focus of this paper is the ornament hoard from the Sopot culture site of Čepin-Ovčara in eastern Slavonia (the Republic of Croatia. The hoard contained pendants and beads made of shells of marine clam Spondylus gaederopus and scaphopod Antalis vulgaris. The paper analyses the context and use wear of the objects in the hoard. The results form a basis for: the reconstruction of the role of some of the items and the ways in which they were worn; the premise that the dynamics and mechanisms of acquisition of ornaments made of the two Mediterranean mollusc species could have differed; and the identification of a cross-cultural pattern of deposition of ornament hoards.
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Hassan, Ruhana; Lee, Suet Yee; Morni, Wan Zabidii Wan
2017-01-01
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.
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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.
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Martinell, Jordi; Kowalewski, Michał; Domènech, Rosa
2012-01-01
We report quantitative analyses of drilling predation on the free-living, tube-dwelling serpulid polychaete Ditrupa arietina from the Cope Cabo marine succession (Pliocene, Spain). Tubes of D. arietina are abundant in the sampled units: 9 bulk samples from 5 horizons yielded ∼5925 specimens of D. arietina. Except for fragmentation, tubes were well preserved. Complete specimens ranged from 3.1 to 13.4 mm in length and displayed allometric growth patterns, with larger specimens being relatively slimmer. Drilled Ditrupa tubes were observed in all samples. Drillholes, identified as Oichnus paraboloides, were characterized by circular to elliptical outline (drillhole eccentricity increased with its diameter), parabolic vertical profile, outer diameter larger than inner diameter, penetration of one tube wall only, narrow range of drill-hole sizes, and non-random (anterior) distribution of drillholes. A total of 233 drilled specimens were identified, with drilling frequencies varying across horizons from 2.7% to 21% (3.9% for pooled data). Many tube fragments were broken across a drillhole suggesting that the reported frequencies are conservative and that biologically-facilitated (drill-hole induced) fragmentation hampers fossil preservation of complete serpulid tubes. No failed or repaired holes were observed. Multiple complete drillholes were present (3.9%). Drilled specimens were significantly smaller than undrilled specimens and tube length and drill-hole diameter were weakly correlated. The results suggest that drillholes were produced by a size-selective, site-stereotypic predatory organism of unknown affinity. The qualitative and quantitative patterns reported here are mostly consistent with previous reports on recent and fossil Ditrupa and reveal parallels with drilling patterns documented for scaphopod mollusks, a group that is ecologically and morphologically similar to Ditrupa. Consistent with previous studies, the results suggest that free-dwelling serpulid
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Wiklund, Helena; Taylor, John D; Dahlgren, Thomas G; Todt, Christiane; Ikebe, Chiho; Rabone, Muriel; Glover, Adrian G
2017-01-01
We present the first DNA taxonomy publication on abyssal Mollusca from the Clarion-Clipperton Zone (CCZ), central Pacific ocean, using material collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise 'AB01' to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration area 'UK-1' in the eastern CCZ. This is the third paper in a series to provide regional taxonomic data for a region that is undergoing intense deep-sea mineral exploration for high-grade polymetallic nodules. Taxonomic data are presented for 21 species from 42 records identified by a combination of morphological and genetic data, including molecular phylogenetic analyses. These included 3 heterodont bivalves, 5 protobranch bivalves, 4 pteriomorph bivalves, 1 caudofoveate, 1 monoplacophoran, 1 polyplacophoran, 4 scaphopods and 2 solenogastres. Gastropoda were recovered but will be the subject of a future study. Seven taxa matched published morphological descriptions for species with deep Pacific type localities, and our sequences provide the first genetic data for these taxa. One taxon morphologically matched a known cosmopolitan species but with a type locality in a different ocean basin and was assigned the open nomenclature ' cf ' as a precautionary approach in taxon assignments to avoid over-estimating species ranges. One taxon is here described as a new species, Ledella knudseni sp. n. For the remaining 12 taxa, we have determined them to be potentially new species, for which we make the raw data, imagery and vouchers available for future taxonomic study. 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.
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Helena Wiklund
2017-10-01
Full Text Available We present the first DNA taxonomy publication on abyssal Mollusca from the Clarion-Clipperton Zone (CCZ, central Pacific ocean, using material collected as part of the Abyssal Baseline (ABYSSLINE environmental survey cruise ‘AB01’ to the UK Seabed Resources Ltd (UKSRL polymetallic-nodule exploration area ‘UK-1’ in the eastern CCZ. This is the third paper in a series to provide regional taxonomic data for a region that is undergoing intense deep-sea mineral exploration for high-grade polymetallic nodules. Taxonomic data are presented for 21 species from 42 records identified by a combination of morphological and genetic data, including molecular phylogenetic analyses. These included 3 heterodont bivalves, 5 protobranch bivalves, 4 pteriomorph bivalves, 1 caudofoveate, 1 monoplacophoran, 1 polyplacophoran, 4 scaphopods and 2 solenogastres. Gastropoda were recovered but will be the subject of a future study. Seven taxa matched published morphological descriptions for species with deep Pacific type localities, and our sequences provide the first genetic data for these taxa. One taxon morphologically matched a known cosmopolitan species but with a type locality in a different ocean basin and was assigned the open nomenclature ‘cf’ as a precautionary approach in taxon assignments to avoid over-estimating species ranges. One taxon is here described as a new species, Ledella knudseni sp. n. For the remaining 12 taxa, we have determined them to be potentially new species, for which we make the raw data, imagery and vouchers available for future taxonomic study. 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.
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Mitogenomics does not resolve deep molluscan relationships (yet?).
Stöger, I; Schrödl, M
2013-11-01
The origin of molluscs among lophotrochozoan metazoans is unresolved and interclass relationships are contradictory between morphology-based, multi-locus, and recent phylogenomic analyses. Within the "Deep Metazoan Phylogeny" framework, all available molluscan mitochondrial genomes were compiled, covering 6 of 8 classes. Genomes were reannotated, and 13 protein coding genes (PCGs) were analyzed in various taxon settings, under multiple masking and coding regimes. Maximum Likelihood based methods were used for phylogenetic reconstructions. In all cases, molluscs result mixed up with lophotrochozoan outgroups, and most molluscan classes with more than single representatives available are non-monophyletic. We discuss systematic errors such as long branch attraction to cause aberrant, basal positions of fast evolving ingroups such as scaphopods, patellogastropods and, in particular, the gastropod subgroup Heterobranchia. Mitochondrial sequences analyzed either as amino acids or nucleotides may perform well in some (Cephalopoda) but not in other palaeozoic molluscan groups; they are not suitable to reconstruct deep (Cambrian) molluscan evolution. Supposedly "rare" mitochondrial genome level features have long been promoted as phylogenetically informative. In our newly annotated data set, features such as genome size, transcription on one or both strands, and certain coupled pairs of PCGs show a homoplastic, but obviously non-random distribution. Apparently congruent (but not unambiguous) signal for non-trivial subclades, e.g. for a clade composed of pteriomorph and heterodont bivalves, needs confirmation from a more comprehensive bivalve sampling. We found that larger clusters not only of PCGs but also of rRNAs and even tRNAs can bear local phylogenetic signal; adding trnG-trnE to the end of the ancestral cluster trnM-trnC-trnY-trnW-trnQ might be synapomorphic for Mollusca. Mitochondrial gene arrangement and other genome level features explored and reviewed herein thus
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"Recent" macrofossil remains from the Lomonosov Ridge, central Arctic Ocean
Le Duc, Cynthia; de Vernal, Anne; Archambault, Philippe; Brice, Camille; Roberge, Philippe
2016-04-01
The examination of surface sediment samples collected from 17 sites along the Lomonosov Ridge at water depths ranging from 737 to 3339 meters during Polarstern Expedition PS87 in 2014 (Stein, 2015), indicates a rich biogenic content almost exclusively dominated by calcareous remains. Amongst biogenic remains, microfossils (planktic and benthic foraminifers, pteropods, ostracods, etc.) dominate but millimetric to centrimetric macrofossils occurred frequently at the surface of the sediment. The macrofossil remains consist of a large variety of taxa, including gastropods, bivalvia, polychaete tubes, scaphopods, echinoderm plates and spines, and fish otoliths. Among the Bivalvia, the most abundant taxa are Portlandia arctica, Hyalopecten frigidus, Cuspidaria glacilis, Policordia densicostata, Bathyarca spp., and Yoldiella spp. Whereas a few specimens are well preserved and apparently pristine, most mollusk shells displayed extensive alteration features. Moreover, most shells were covered by millimeter scale tubes of the serpulid polychaete Spirorbis sp. suggesting transport from low intertidal or subtidal zone. Both the ecological affinity and known geographic distribution of identified bivalvia as named above support the hypothesis of transportation rather than local development. In addition to mollusk shells, more than a hundred fish otoliths were recovered in surface sediments. The otoliths mostly belong to the Gadidae family. Most of them are well preserved and without serpulid tubes attached to their surface, suggesting a local/regional origin, unlike the shell remains. Although recovered at the surface, the macrofaunal assemblages of the Lomonosov Ridge do not necessarily represent the "modern" environments as they may result from reworking and because their occurrence at the surface of the sediment may also be due to winnowing of finer particles. Although the shells were not dated, we suspect that their actual ages may range from modern to several thousands of
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Dentalium beads - shells of fosillised sea molluscs at the Vinča-Belo brdo site
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Dimitrijević Vesna
2010-01-01
Full Text Available During excavation of the Vinča-Belo Brdo site a significant number of decorated items made from clay, stone, bone, and seashells or snail shells have been collected over the years. Amongst the decorated objects which could be classified as jewellery the majority are bracelets, pendants, and beads made from Spondylus and Glycymeris shells, as well as beads made from Dentalium shells. The appearance of these beads and the question of their origin have not yet been specifically considered within studies of prehistoric cultures in the central Balkans. Furthermore, they have rarely been illustrated and mentioned in archaeological site inventories, which we presume has not been because of their poor representation, but rather because of their being unfamiliar. The aim of this work is therefore to: a systematize data about Dentalium beads from all phases of excavation of the Belo Brdo site in Vinča; b to show the importance of this kind of jewellery in the study of resources around the Vinča settlement; and c to indicate the wider chronological perspective and the significance of studying Dentalium beads within the prehistory of the central Balkans. Dentalium is a carnivorous Scaphopoda sea mollusc, uncommon and insufficiently studied. Representatives of this class of Scaphopoda have been found on Serbian territory in the Badenian sediments, deposited fifteen million years ago. Badenian sediments were discovered around Loznica, Belgrade, Aranđelovac, Golubac, Zaječar, and Negotin. The region of Belgrade and the surrounding area had been covered by a warm, shallow sea of normal salination. On the territory of Belgrade, offsprings of the Badenian sediments, rich in fossils, have been discovered in the city centre (Tašmajdan, Kalemegdan, as well as in many surrounding places (Rakovica, Kaluđerica, Leštani, and Jajinci (fig. 2. Scaphopod shells found at the Vinča-Belo Brdo archaeological site are usually transversally broken. Judging by the basic
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Luiz Ricardo L. Simone
2009-01-01
the main goal of this paper, the taxa Scaphopoda and Bivalvia are supported by 8 and by 7 synapomorphies respectively. The taxon Protobranchia resulted paraphyletic. Both scaphopod orders resulted monophyletic. The obtained cladogram is: ((((Coccodentalium carduus - Paradentalium disparile (Polyschides noronhensis - Gadila brasiliensis ((Solemya occidentalis - S. notialis (Propeleda carpenteri (Ennucula puelcha (Barbatia cancellaria - Serratina capsoides (Propilidium curumim - Nautilus pompilius - Lolliguncula brevis.Este estudo analisa a morfologia e anatomia detalhadas de 4 espécies de Scaphopoda e 5 espécies de bivalves protobrânquios. Ambas as classes são tradicionalmente agrupadas no táxon Diasoma, o qual vem sendo questionado por diferentes metodologias, tais como molecular e de desenvolvimento. Este estudo é desenvolvido sob uma metodologia filogenética, a qual a maior preocupação é fornecer um procedimento inteligível e testável. As espécies de Scaphopoda analisadas provieram da costa brasileira e pertencem à família Dentaliidae [(1 Coccodentalium carduus; (2 Paradentalium disparile] e Gadilidae [(3 Polyschides noronhensis, n. sp. do Arquipélago de Fernando de Noronha; (4 Gadila braziliensis]. Estas espécies representam os ramos principais da classe Scaphopoda. Dos bivalves protobrânquios, representantes das famílias Solemyidae [(5 Solemya occidentalis, da Flórida; S. notialis, n. sp. do S.E. Brasil], Nuculanidae [(6 Propeleda carpentieri, da Flórida] e Nuculidae [(7 Ennucula puelcha, do sul do Brasil] são incluídos. Estas espécies representam os principais ramos dos bivalves basais. As descrições anatômicas de S. occidentalis e de P. carpentieri estão sendo publicadas em outro artigo, as das demais espécies estão incluídas neste, o qual também inclui um completo tratamento taxonômico. Além dessas espécies, representantes de outros táxons são operacionalmente incluídos como parte do ingroup (então os índices s