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David J Siveter - One of the best experts on this subject based on the ideXlab platform.
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Electronic Supplementary Information Figure 1. from A new crustacean from the Herefordshire (Silurian) Lagerstätte, UK, and its significance in Malacostracan evolution
2017Co-Authors: Derek E G Briggs, Mark D Sutton, David J Siveter, David LeggAbstract:Cascolus ravitis gen. et sp. nov. is a three-dimensionally preserved fossil crustacean with soft parts from the Herefordshire (Silurian) Lagerstätte, UK. It is characterized by a head with a head shield and five limb pairs and a thorax (pereon) with nine appendage-bearing segments followed by an apodous abdomen (pleon). All the appendages except the first are biramous and have a gnathobase. The post-mandibular appendages are similar one to another, and bear petal-shaped epipods that probably functioned as a part of the respiratory–circulatory system. Cladistic analysis resolves the new taxon as a stem-group leptostracan (Malacostraca). This well-preserved arthropod provides novel insights into the evolution of appendage morphology, tagmosis and the possible respiratory–circulatory physiology of a basal Malacostracan
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A new crustacean from the Herefordshire (Silurian) Lagerstätte, UK, and its significance in Malacostracan evolution
2017Co-Authors: Derek E G Briggs, Mark D Sutton, David J Siveter, David LeggAbstract:Cascolus ravitis gen. et sp. nov. is a three-dimensionally preserved fossil crustacean with soft parts from the Herefordshire (Silurian) Lagerstätte, UK. It is characterized by a head with a head shield and five limb pairs, and a thorax (pereon) with nine appendage-bearing segments followed by an apodous abdomen (pleon). All the appendages except the first are biramous and have a gnathobase. The post-mandibular appendages are similar one to another, and bear petal-shaped epipods that probably functioned as a part of the respiratory–circulatory system. Cladistic analysis resolves the new taxon as a stem-group leptostracan (Malacostraca). This well-preserved arthropod provides novel insights into the evolution of appendage morphology, tagmosis and the possible respiratory–circulatory physiology of a basal Malacostracan
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a new phyllocarid crustacea Malacostraca from the silurian fossil lagerstatte of herefordshire uk
Proceedings of The Royal Society B: Biological Sciences, 2004Co-Authors: Derek E G Briggs, Mark D Sutton, David J SiveterAbstract:A new three-dimensionally preserved arthropod, Cinerocaris magnifica, from the Wenlock Series (Silurian) of Herefordshire, UK, is described and assigned to the Phyllocarida (Crustacea). The description and reconstruction are based on specimens that have been serially ground, reconstructed by computer and rendered in three dimensions as coloured virtual models. Cinerocaris magnifica displayed the tagmosis characteristic of phyllocarids, with eight thoracic and seven abdominal somites, terminating in a telson with furca. The remarkable preservation of the appendages makes this the earliest completely known Malacostracan crustacean. Two pairs of antennae (the first with two flagella) were followed by a mandible and first maxilla, each with a slender palp-like ramus. The second maxilla consisted of a limb stem with endites and an endopod that tapered distally. There was no exopod. The thoracopods comprised a limb stem with six or seven endites, an arrangement previously known only in entomostracans, and an endopod with about five endites. Flap-like outer rami correspond to an exopod and epipods. The pleopods bore two long slender oar-blade-like rami. Cladistic analysis places C. magnifica as a plesion within the Echinocaridina. It provides critical evidence of the limb morphology of an early Malacostracan, which will be important in understanding crustacean evolution.
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A new phyllocarid (Crustacea: Malacostraca) from the Silurian Fossil-Lagerstatte of Herefordshire, UK.
2004Co-Authors: De Briggs, David J SiveterAbstract:A new three-dimensionally preserved arthropod, Cinerocaris magnifica, from the Wenlock Series (Silurian) of Herefordshire, UK, is described and assigned to the Phyllocarida (Crustacea). The description and reconstruction are based on specimens that have been serially ground, reconstructed by computer and rendered in three dimensions as coloured virtual models. Cinerocaris magnifica displayed the tagmosis characteristic of phyllocarids, with eight thoracic and seven abdominal somites, terminating in a telson with furca. The remarkable preservation of the appendages makes this the earliest completely known Malacostracan crustacean. Two pairs of antennae (the first with two flagella) were followed by a mandible and first maxilla, each with a slender palp-like ramus. The second maxilla consisted of a limb stem with endites and an endopod that tapered distally. There was no exopod. The thoracopods comprised a limb stem with six or seven endites, an arrangement previously known only in entomostracans, and an endopod with about five endites. Flap-like outer rami correspond to an exopod and epipods. The pleopods bore two long slender oar-blade-like rami. Cladistic analysis places C. magnifica as a plesion within the Echinocaridina. It provides critical evidence of the limb morphology of an early Malacostracan, which will be important in understanding crustacean evolution
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Silurian Fossil-Lagerstätte of Herefordshire, UK
2003Co-Authors: Derek E G Briggs, Mark D Sutton, David J SiveterAbstract:A new three-dimensionally preserved arthropod, Cinerocaris magnifica, from the Wenlock Series (Silurian) of Herefordshire, UK, is described and assigned to the Phyllocarida (Crustacea). The description and reconstruction are based on specimens that have been serially ground, reconstructed by computer and rendered in three dimensions as coloured virtual models. Cinerocaris magnifica displayed the tagmosis characteristic of phyllocarids, with eight thoracic and seven abdominal somites, terminating in a telson with furca. The remarkable preservation of the appendages makes this the earliest completely known Malacostracan crustacean. Two pairs of antennae (the first with two flagella) were followed by a mandible and first maxilla, each with a slender palp-like ramus. The second maxilla consisted of a limb stem with endites and an endopod that tapered distally. There was no exopod. The thoracopods comprised a limb stem with six or seven endites, an arrangement previously known only in entomostracans, and an endopod with about five endites. Flap-like outer rami correspond to an exopod and epipods. The pleopods bore two long slender oar-blade-like rami. Cladistic analysis places C. magnifica as a plesion within the Echino-caridina. It provides critical evidence of the limb morphology of an early Malacostracan, which will be important in understanding crustacean evolution
Ortuño, Vicente M. - One of the best experts on this subject based on the ideXlab platform.
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Hábitat inusual para Bathynellacea (Crustacea, Malacostraca): primer registro de este crustáceo de agua subterránea en el sustrato superficial mesovoide (MSS)
'Editorial CSIC', 2021Co-Authors: Camacho Pérez Ana, Ortuño, Vicente M.Abstract:[EN] First world record of a crustacean (Malacostraca, Bathynellacea) that lives exclusively in groundwater in an unusual habitat, the mesovoid shallow substratum (MSS). The MSS is a terrestrial subterranean medium with high and constant relative humidity. Specimens of the family Parabathynellidae have been found in sam- pling devices set to collect terrestrial subterranean fauna in the MSS of Sierra de Guadarrama National Park (Madrid, Spain). Two species belonging to two different genera, Hexabathynella nicoleiana Camacho, 1986 and Hexaiberobathynella mateusi (Galhano, 1967), already known to occur in the province of Madrid, have been identified by morphological study, whereas their 18S gene sequences confirmed their generic ascription[ES] En este trabajo se documenta por primera vez el hallazgo de ejemplares de un crustáceo (Malacostraca, Bathynellacea) que vive exclusivamente en las aguas subterráneas de todo el mundo, en un hábitat inusual: el medio subterráneo superficial (MSS),un medio terrestre sin luz y saturado de humedad. Especímenes de la familia Parabathynellidae han sido encontrados en dispositivos de muestreo dispuestos para la recogida de fauna subterránea terrestre en el MSS del Parque Nacional de la Sierra de Guadarrama (Madrid, España). Se han identificado dos especies, de dos géneros diferentes, Hexabathynella nicoleianaCamacho, 1986 y Hexaiberobathynella mateusi (Galhano, 1967),mediante estudio morfológico. Las secuencias del gen 18S de varios ejemplares confirman su adscripción genérica. Estas especies eran ya conocidas en la provincia de Madrid.This work was funded by the project “Study of the diversity and distribution of the animal species of the Mesovoid Shallow Substratum in enclaves of high Mountain (Sierra de Guadarrama National Park)”, conceded by the Autonomous Organism of National Parks of Spain Ref. (1143/2014). This work has also been supported by CGL2015-66571-P, MINECO/FEDER projects
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Hábitat inusual para Bathynellacea (Crustacea, Malacostraca): primer registro de este crustáceo de agua subterránea en el sustrato superficial mesovoide (MSS)
'Editorial CSIC', 2019Co-Authors: Camacho Ana, Ortuño, Vicente M.Abstract:First world record of a crustacean (Malacostraca, Bathynellacea) that lives exclusively in groundwater in an unusual habitat, the mesovoid shallow substratum (MSS). The MSS is a terrestrial subterranean medium with high and constant relative humidity. Specimens of the family Parabathynellidae have been found in sampling devices set to collect terrestrial subterranean fauna in the MSS of Sierra de Guadarrama National Park (Madrid, Spain). Two species belonging to two different genera, Hexabathynella nicoleiana Camacho, 1986 and Hexaiberobathynella mateusi (Galhano, 1967), already known to occur in the province of Madrid, have been identified by morphological study, whereas their 18S gene sequences confirmed their generic ascription.En este trabajo se documenta por primera vez el hallazgo de ejemplares de un crustáceo (Malacostraca, Bathynellacea) que vive exclusivamente en las aguas subterráneas de todo el mundo, en un hábitat inusual: el medio subterráneo superficial (MSS), un medio terrestre sin luz y saturado de humedad. Especímenes de la familia Parabathynellidae han sido encontrados en dispositivos de muestreo dispuestos para la recogida de fauna subterránea terrestre en el MSS del Parque Nacional de la Sierra de Guadarrama (Madrid, España). Se han identificado dos especies, de dos géneros diferentes, Hexabathynella nicoleiana Camacho, 1986 y Hexaiberobathynella mateusi (Galhano, 1967), mediante estudio morfológico. Las secuencias del gen 18S de varios ejemplares confirman su adscripción genérica. Estas especies eran ya conocidas en la provincia de Madrid
Xin Shen - One of the best experts on this subject based on the ideXlab platform.
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phylomitogenomics of Malacostraca arthropoda crustacea
Acta Oceanologica Sinica, 2015Co-Authors: Xin Shen, Mei Tian, Binlun Yan, Ka Hou ChuAbstract:Along with the sequencing technology development and continual enthusiasm of researchers on the mitochondrial genomes, the number of metazoan mitochondrial genomes reported has a tremendous growth in the past decades. Phylomitogenomics—reconstruction of phylogenetic relationships based on mitochondrial genomic data—is now possible across large animal groups. Crustaceans in the class Malacostraca display a high diversity of body forms and include large number of ecologically and commercially important species. In this study, comprehensive and systematic analyses of the phylogenetic relationships within Malacostraca were conducted based on 86 mitochondrial genomes available from GenBank. Among 86 Malacostracan mitochondrial genomes, 54 species have identical major gene arrangement (excluding tRNAs) to pancrustacean ground pattern, including six species from Stomatopoda, three species from Amphipoda, two krill, seven species from Dendrobranchiata (Decapoda), and 36 species from Pleocyemata (Decapoda). However, the other 32 mitochondrial genomes reported exhibit major gene rearrangements. Phylogenies based on Bayesian analyses of nucleotide sequences of the protein-coding genes produced a robust tree with 100% posterior probability at almost all nodes. The results indicate that Amphipoda and Isopoda cluster together (Edriophthalma) (BPP=100). Phylomitogenomic analyses strong support that Euphausiacea is nested within Decapoda, and closely related to Dendrobranchiata, which is also consistent with the evidence from developmental biology. Yet the taxonomic sampling of mitochondrial genome from Malacostraca is very biased to the order Decapoda, with no complete mitochondrial genomes reported from 11 of the 16 orders. Future researches on sequencing the mitochondrial genomes from a wide variety of Malacostracans are necessary to further elucidate the phylogeny of this important group of animals. With the increase in mitochondrial genomes available, phylomitogenomics will emerge as an important component in the Tree of Life researches.
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the complete mitochondrial genome sequence of euphausia pacifica Malacostraca euphausiacea reveals a novel gene order and unusual tandem repeats
Genome, 2011Co-Authors: Xin Shen, Haiqing Wang, Minxiao WangAbstract:Euphausiid krill are dominant organisms in the zooplankton population and play a central role in marine ecosystems. Euphausia pacifica (Malacostraca: Euphausiacea) is one of the most important and dominant crustaceans in the North Pacific Ocean. In this paper, we described the gene content, organization, and codon usage of the E. pacifica mitochondrial genome. The mitochondrial genome of E. pacifica is 16 898 bp in length and contains a standard set of 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes. Trans location of three transfer RNAs (trnL(1), trnL(2), and trnW) was found in the E. pacifica mitochondrial genome when comparing with the pancrustacean ground pattern. The rate of K(a)/K(s), in 13 protein-coding genes among three krill is much less than 1, which indicates a strong purifying selection within this group. The largest noncoding region in the E. pacifica mitochondrial genome contains one section with tandem repeats (4.7 x 154 bp), which are the largest tandem repeats found in Malacostracan mitochondrial genomes so far. All analyses based on nucleotide and amino acid data strongly support the monophyly of Stomatopoda, Penacidae, Caridea, Brachyura, and Euphausiacea. The Bayesian analysis of nucleotide and amino acid datasets strongly supports the close relationship between Euphausiacea and Decapoda, which confirms traditional findings. The maximum likelihood analysis based on amino acid data strongly supports the close relationship between Euphausiacea and Penaeidae, which destroys the monophyly of Decapoda.
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the mitochondrial genome of euphausia superba prydz bay crustacea Malacostraca euphausiacea reveals a novel gene arrangement and potential molecular markers
Molecular Biology Reports, 2010Co-Authors: Xin Shen, Haiqing Wang, Mei Tian, Minxiao WangAbstract:Euphausiid krill are dominant organisms in the zooplankton population and play a central role in marine ecosystems. In this paper, we described the gene organization, gene rearrangement and codon usage in the mitochondrial genome of Euphausia superba Dana 1852 (sampling from Prydz Bay, PB). The mitochondrial genome of E. superba is more than 15,498 bp in length (partial non-coding region was not determined). Translocation of four tRNAs (trnL1, trnL2, trnW and trnI) and duplication of one tRNA (trnN) were founded in the mitochondrial genome of E. superba when comparing its genome with the pancrustacean ground pattern. To investigate the phylogenetic relationship within Malacostraca, phylogenetic trees based on currently available Malacostracan mitochondrial genomes were built with the maximum likelihood and the Bayesian models. All analyses based on nucleotide and amino acid data strongly support the monophyly of Stomatopoda, Penaeidae, Caridea, and Brachyura, which is consistent with previous research. However, the taxonomic position of Euphausiacea within Malacostraca is unstable. From comparing the mitochondrial genome between E. superba (PB) and E. superba (sampling from Weddell Sea, WS), we found that nad2 gene contains maximal variation with 61 segregating sites, following by nad5 gene which has 12 segregating sites. Thus, nad2 and nad5 genes may be used as potential molecular markers to study the inherit diversity among different E. superba groups, which would be helpful to the exploitation and management of E. superba resources.
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the complete mitochondrial genome of the ridgetail white prawn exopalaemon carinicauda holthuis 1950 crustacean decapoda palaemonidae revealed a novel rearrangement of trna genes
Gene, 2009Co-Authors: Xin Shen, Mei Tian, Mingan Sun, Hanliang Cheng, Fangqing Zhao, Xueping MengAbstract:The complete mitochondrial (mt) DNA sequence was determined for a ridgetail white prawn, Exopalaemon carinicauda Holthuis, 1950 (Crustacea: Decopoda: Palaemonidae). The mt genome is 15,730 bp in length, encoding a standard set of 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, which is typical for metazoans. The majority-strand consists of 33.6% A, 23.0% C, 13.4% G, and 30.0% T bases (AT skew = 0.057: GC skew = -0.264). A total of 1045 bp of non-coding nucleotides were observed in 16 intergenic regions,,including a major A+ T rich (79.7%) noncoding region (886 bp). A novel translocation of tRNA(Pro) and tRNA(Thr) was found when comparing this genome with the pancrustacean ground pattern indicating that gene order is not conserved among caridean mitochondria. Furthermore, the rate of Ka/Ks in 13 protein-coding genes between three caridean species is Much less than 1, which indicates a strong Purifying selection within this group. To investigate the phylogenetic relationship within Malacostraca, phylogenetic trees based oil Currently available Malacostracan complete mitochondrial sequences were built with the maximum likelihood and Bayesian models. All analyses based oil nucleotide and amino acid data strongly support the monophyly of Decapoda. The Penaeidae, Reptantia, Caridea, and Meiura clades were also recovered as monophyletic groups with Strong Statistical Support. However, the phylogenetic relationships within Pleocyemata are unstable, as represented by the inclusion or exclusion of Caridea. (C) 2009 Elsevier B.V. All rights reserved.
John A H Benzie - One of the best experts on this subject based on the ideXlab platform.
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the complete sequence of the mitochondrial genome of the crustacean penaeus monodon are Malacostracan crustaceans more closely related to insects than to branchiopods
Molecular Biology and Evolution, 2000Co-Authors: Kate Wilson, Valma Cahill, E Ballment, John A H BenzieAbstract:: The complete sequence of the mitochondrial genome of the giant tiger prawn, Penaeus monodon (Arthropoda, Crustacea, Malacostraca), is presented. The gene content and gene order are identical to those observed in Drosophila yakuba. The overall AT composition is lower than that observed in the known insect mitochondrial genomes, but higher than that observed in the other two crustaceans for which complete mitochondrial sequence is available. Analysis of the effect of nucleotide bias on codon composition across the Arthropoda reveals a trend with the crustaceans represented showing the lowest proportion of AT-rich codons in mitochondrial protein genes. Phylogenetic analysis among arthropods using concatenated protein-coding sequences provides further support for the possibility that Crustacea are paraphyletic. Furthermore, in contrast to data from the nuclear gene EF1alpha, the first complete sequence of a Malacostracan mitochondrial genome supports the possibility that Malacostraca are more closely related to Insecta than to Branchiopoda.
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the complete sequence of the mitochondrial genome of the crustacean penaeus monodon are Malacostracan crustaceans more closely related to insects than to branchiopods
Molecular Biology and Evolution, 2000Co-Authors: Kate J Wilson, Valma Cahill, E Ballment, John A H BenzieAbstract:The complete sequence of the mitochondrial genome of the giant tiger prawn, Penaeus monodon (Arthropoda, Crustacea, Malacostraca), is presented. The gene content and gene order are identical to those observed in Drosophila yakuba. The overall AT composition is lower than that observed in the known insect mitochondrial genomes, but higher than that observed in the other two crustaceans for which complete mitochondrial sequence is available. Analysis of the effect of nucleotide bias on codon composition across the Arthropoda reveals a trend with the crustaceans represented showing the lowest proportion of AT-rich codons in mitochondrial protein genes. Phylogenetic analysis among arthropods using concatenated protein-coding sequences provides further support for the possibility that Crustacea are paraphyletic. Furthermore, in contrast to data from the nuclear gene EF1alpha, the first complete sequence of a Malacostracan mitochondrial genome supports the possibility that Malacostraca are more closely related to Insecta than to Branchiopoda.
Aziz A Aboobaker - One of the best experts on this subject based on the ideXlab platform.
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comparative genomic analysis of innate immunity reveals novel and conserved components in crustacean food crop species
BMC Genomics, 2017Co-Authors: Alvina G Lai, Aziz A AboobakerAbstract:Growing global demands for crustacean food crop species have driven large investments in aquaculture research worldwide. However, large-scale production is susceptible to pathogen-mediated destruction particularly in developing economies. Thus, a thorough understanding of the immune system components of food crop species is imperative for research to combat pathogens. Through a comparative genomics approach utilising extant data from 55 species, we describe the innate immune system of the class Malacostraca, which includes all food crop species. We identify 7407 Malacostracan genes from 39 gene families implicated in different aspects of host defence and demonstrate dynamic evolution of innate immunity components within this group. Malacostracans have achieved flexibility in recognising infectious agents through divergent evolution and expansion of pathogen recognition receptors genes. Antiviral RNAi, Toll and JAK-STAT signal transduction pathways have remained conserved within Malacostraca, although the Imd pathway appears to lack several key components. Immune effectors such as the antimicrobial peptides (AMPs) have unique evolutionary profiles, with many Malacostracan AMPs not found in other arthropods. Lastly, we describe four putative novel immune gene families, potentially representing important evolutionary novelties of the Malacostracan immune system. Our analyses across the broader Malacostraca have allowed us to not only draw analogies with other arthropods but also to identify evolutionary novelties in immune modulation components and form strong hypotheses as to when key pathways have evolved or diverged. This will serve as a key resource for future immunology research in crustacean food crops.
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Comparative genomic analysis of innate immunity reveals novel and conserved components in crustacean food crop species
BMC, 2017Co-Authors: Alvina G Lai, Aziz A AboobakerAbstract:Abstract Background Growing global demands for crustacean food crop species have driven large investments in aquaculture research worldwide. However, large-scale production is susceptible to pathogen-mediated destruction particularly in developing economies. Thus, a thorough understanding of the immune system components of food crop species is imperative for research to combat pathogens. Results Through a comparative genomics approach utilising extant data from 55 species, we describe the innate immune system of the class Malacostraca, which includes all food crop species. We identify 7407 Malacostracan genes from 39 gene families implicated in different aspects of host defence and demonstrate dynamic evolution of innate immunity components within this group. Malacostracans have achieved flexibility in recognising infectious agents through divergent evolution and expansion of pathogen recognition receptors genes. Antiviral RNAi, Toll and JAK-STAT signal transduction pathways have remained conserved within Malacostraca, although the Imd pathway appears to lack several key components. Immune effectors such as the antimicrobial peptides (AMPs) have unique evolutionary profiles, with many Malacostracan AMPs not found in other arthropods. Lastly, we describe four putative novel immune gene families, potentially representing important evolutionary novelties of the Malacostracan immune system. Conclusion Our analyses across the broader Malacostraca have allowed us to not only draw analogies with other arthropods but also to identify evolutionary novelties in immune modulation components and form strong hypotheses as to when key pathways have evolved or diverged. This will serve as a key resource for future immunology research in crustacean food crops
