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Orietta Nicolis - One of the best experts on this subject based on the ideXlab platform.
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using a spatio temporal bayesian approach to estimate the relative abundance index of yellow Squat Lobster cervimunida johni off chile
Fisheries Research, 2018Co-Authors: Joaquin Cavieres, Orietta NicolisAbstract:Abstract Estimating relative abundance indexes based on spatio-temporal variations in fishing effort has been one of the greatest challenges in fisheries sciences. Obtained from the catch per unit of effort (CPUE), such indexes are generally used within evaluation models as "relative" to the stock abundance. Herein, a Bayesian spatio-temporal model was used to obtain an index for yellow Squat Lobster (Cervimunida johni) between the III and IV regions of Chile based on CPUE data (Kg/h.a) from fishing logs. The spatial field was approximated by a GMRF using the SPDE method and posterior distributions of interest were approximated using the Integrated Nested Laplace Approximation (INLA). By taking into account the distributional assumption of the CPUE the proposed model showed a good fit to the observed data. The proposed method allowed obtaining a relative index of abundance which could be included within the classic stock assessment models.
C. N. Roterman - One of the best experts on this subject based on the ideXlab platform.
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Systematic palaeontology.............................................................................................................................. 126 Acknowledgements...
2016Co-Authors: S. T. Ahyong, C. N. RotermanAbstract:Pristinaspinidae, a new family of Cretaceous kiwaiform stem-lineage Squat Lobster (Anomura, Chirostyloidea
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pristinaspinidae a new family of cretaceous kiwaiform stem lineage Squat Lobster anomura chirostyloidea
Scripta Geologica, 2014Co-Authors: S. T. Ahyong, C. N. RotermanAbstract:The chirostyloid Squat Lobster Pristinaspina gelasina from the Upper Cretaceous of Alaska is most closely related to members of the genus Kiwa (Kiwaidae) as indicated by the presence of supraocular spines, a medially carinate rostrum and similar carapace groove patterns. Evidence from morphology, stratigraphic position and molecular divergence estimates of extant chirostyloids supports its position in the stem of Kiwaidae. Pristinaspina, however, also differs significantly from kiwaids and is here assigned to a new family, Pristinaspinidae. The chief distinction between the free-living pristinaspinids and vent- or seep-associated kiwaids (and an important synapomorphy of the latter) is the enlargement of the metabranchial regions in kiwaids, which meet in the mid-line and separate the cardiac region from the intestinal region. The enlarged metabranchial regions of kiwaids may have improved respiration in poorly oxygenated, chemosynthetically affected waters. This appears to track a major shift in the deep-water ecology of kiwaiform Squat Lobsters, that is, the movement into chemosynthetic habitats.
S. T. Ahyong - One of the best experts on this subject based on the ideXlab platform.
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Systematic palaeontology.............................................................................................................................. 126 Acknowledgements...
2016Co-Authors: S. T. Ahyong, C. N. RotermanAbstract:Pristinaspinidae, a new family of Cretaceous kiwaiform stem-lineage Squat Lobster (Anomura, Chirostyloidea
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pristinaspinidae a new family of cretaceous kiwaiform stem lineage Squat Lobster anomura chirostyloidea
Scripta Geologica, 2014Co-Authors: S. T. Ahyong, C. N. RotermanAbstract:The chirostyloid Squat Lobster Pristinaspina gelasina from the Upper Cretaceous of Alaska is most closely related to members of the genus Kiwa (Kiwaidae) as indicated by the presence of supraocular spines, a medially carinate rostrum and similar carapace groove patterns. Evidence from morphology, stratigraphic position and molecular divergence estimates of extant chirostyloids supports its position in the stem of Kiwaidae. Pristinaspina, however, also differs significantly from kiwaids and is here assigned to a new family, Pristinaspinidae. The chief distinction between the free-living pristinaspinids and vent- or seep-associated kiwaids (and an important synapomorphy of the latter) is the enlargement of the metabranchial regions in kiwaids, which meet in the mid-line and separate the cardiac region from the intestinal region. The enlarged metabranchial regions of kiwaids may have improved respiration in poorly oxygenated, chemosynthetically affected waters. This appears to track a major shift in the deep-water ecology of kiwaiform Squat Lobsters, that is, the movement into chemosynthetic habitats.
Enrique Macpherson - One of the best experts on this subject based on the ideXlab platform.
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uroptychus tuerkayi sp nov anomura chirostylidae a new Squat Lobster from the atlantis great meteor seamount chain in the eastern atlantic
Crustaceana, 2017Co-Authors: Keiji Baba, Enrique MacphersonAbstract:A new species of chirostylid Squat Lobster, Uroptychus tuerkayi sp. nov., is described based upon material collected by the French “Seamount 2” project (1993) from the Atlantis-Great Meteor Seamount Chain south of the Azores Islands, at a depth of 340-730 m. Uroptychus tuerkayi resembles U. maroccanus Turkay, 1976 from the Moroccan coast, but it can be readily distinguished by the eyes being distinctly longer instead of as long as broad (globular in U. maroccanus ), the antennal article 5 with a small instead of prominent distomesial spine, the anterolateral spine of the carapace slightly smaller than or subequal to, instead of much smaller than the lateral orbital spine, the pterygostomian flap anteriorly acuminate and not strongly produced to a spine as in U. maroccanus , and in having pereopod 1 with obsolescent instead of distinct spines on the merus and carpus. This is the sixth species of Uroptychus from the eastern Atlantic. A key to the eastern Atlantic species of Uroptychus is provided.
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deep under the sea unraveling the evolutionary history of the deep sea Squat Lobster paramunida decapoda munididae
Evolution, 2012Co-Authors: Patricia Cabezas, Enrique Macpherson, Isabel Sanmartin, Gustav Paulay, Annie MachordomAbstract:The diversification of Indo-Pacific marine fauna has long captivated the attention of evolutionary biologists. Previous studies have mainly focused on coral reef or shallow water-associated taxa. Here, we present the first attempt to reconstruct the evolutionary history--phylogeny, diversification, and biogeography--of a deep-water lineage. We sequenced the molecular markers 16S, COI, ND1, 18S, and 28S for nearly 80% of the nominal species of the Squat Lobster genus Paramunida. Analyses of the molecular phylogeny revealed an accelerated diversification in the late Oligocene-Miocene followed by a slowdown in the rate of lineage accumulation over time. A parametric biogeographical reconstruction showed the importance of the southwest Pacific area, specifically the island arc of Fiji, Tonga, Vanuatu, Wallis, and Futuna, for diversification of Squat Lobsters, probably associated with the global warming, high tectonic activity, and changes in oceanic currents that took place in this region during the Oligocene-Miocene period. These results add strong evidence to the hypothesis that the Neogene was a period of major diversification for marine organisms in both shallow and deep waters.
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a new Squat Lobster crustacea decapoda anomura chirostylidae from off nw spain
Zootaxa, 2012Co-Authors: Keiji Baba, Enrique MacphersonAbstract:Uroptychus cartesi, a new species of Squat Lobster belonging to the family Chirostylidae, is described based upon material recently collected from the Bank of Galicia, a deep seamount located off north-west Spain. This is now the fifth species of the genus known from the eastern Atlantic. The four species previously recorded in the region (U. bouvieri, U. concolor, U. maroccanus and U. rubrovittatus) are morphologically rather remote from the new species. The spinose carapace lateral margin links U. cartesi to U. bouvieri but the other characters displayed by the new species are largely different from those of that species. Uroptychus cartesi is distinguished from U. bouvieri by the epigastric region having denticles arranged in small arcs transversely rather than a pair of spines behind the eyes; the anterolateral spine of the carapace is much larger than, instead of subequal to, the lateral orbital spine; the P2–4 propodi are slightly more than half, instead of twice, the length of dactyli; and the penultimate flexor marginal spine of P2–4 dactyli are twice as broad as, rather than as broad as the antepenultimate spine. A key to the species of Uroptychus from the eastern Atlantic is provided.
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Squat Lobster assemblages on seamounts differ from some but not all deep sea habitats of comparable depth
Marine Ecology, 2010Co-Authors: Ashley A Rowden, Enrique Macpherson, Shane T Ahyong, Kareen E Schnabel, Thomas A Schlacher, Bertrand Richer De ForgesAbstract:This study was carried out to test the hypothesis that benthic communities on seamounts are distinct from those of other deep-sea habitats at comparable depths. Analysis of the Squat Lobster fauna of deep-sea habitats in the Southwestern Pacific revealed that the species composition of assemblages on seamounts was not statistically dissimilar from assemblages on slope and plateau habitat at comparable depths. However, compositional differences were observed between seamount and rise and ridge habitat. Differences in assemblage composition between seamount and ridge habitat were statistically significant for two of the four ridge systems examined. Assemblages on seamounts that were distinct from non-seamount ridge habitat were typically dominated by small-bodied species with an abbreviated larval stage. Various environmental variables were correlated with the observed assemblage patterns observed; depth-related variables may account for differences between seamount and rise assemblages, whilst differences in POC flux likely play a role in determining the assemblage compositional patterns between seamount and non-seamount ridge habitat. Extensive pre-analysis data treatment was required to ensure that multivariate analyses of assemblage data from seamount and non-seamount habitats were robust. Our results confirm the findings of recent studies that found no compositional differences in assemblages from seamount and slope habitats, and support the idea that dissimilarity between seamount assemblages on different ridge systems increases with geographic distance. Further research will be required before the generality of these findings can be confirmed.
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morphological and molecular description of new species of Squat Lobster crustacea decapoda galatheidae from the solomon and fiji islands south west pacific
Zoological Journal of the Linnean Society, 2009Co-Authors: Patricia Cabezas, Enrique Macpherson, Annie MachordomAbstract:The family Galatheidae is among the most diverse families of anomuran decapod crustaceans, and the South-West Pacific is a biodiversity hot spot for these Squat Lobsters. Attempts to clarify the taxonomic and evolutionary relationships of the Galatheidae on the basis of morphological and molecular data have revealed the existence of several cryptic species, differentiated only by subtle morphological characters. Despite these efforts, however, relationships among genera are poorly understood, and the family is in need of a detailed systematic review. In this study, we assess material collected in different surveys conducted in the Solomon Islands, as well as comparative material from the Fiji Islands, by examining both the morphology of the specimens and two mitochondrial markers (cytochrome oxidase subunit I, COI, and 16S rRNA). These two sources of data revealed the existence of eight new species of Squat Lobster, four of which were ascribed to the genus Munida, two to the genus Paramunida, one to the genus Plesionida, and the last species was ascribed to the genus Agononida. These eight species are described along with phylogenetic relationships at the genus level. Our findings support the taxonomic status of the new species, yet the phylogenetic relationships are not yet fully resolved. Further molecular analysis of a larger data set of species, and more conserved genes, will help clarify the systematics of this group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156, 465–493.
Annie Machordom - One of the best experts on this subject based on the ideXlab platform.
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deep under the sea unraveling the evolutionary history of the deep sea Squat Lobster paramunida decapoda munididae
Evolution, 2012Co-Authors: Patricia Cabezas, Enrique Macpherson, Isabel Sanmartin, Gustav Paulay, Annie MachordomAbstract:The diversification of Indo-Pacific marine fauna has long captivated the attention of evolutionary biologists. Previous studies have mainly focused on coral reef or shallow water-associated taxa. Here, we present the first attempt to reconstruct the evolutionary history--phylogeny, diversification, and biogeography--of a deep-water lineage. We sequenced the molecular markers 16S, COI, ND1, 18S, and 28S for nearly 80% of the nominal species of the Squat Lobster genus Paramunida. Analyses of the molecular phylogeny revealed an accelerated diversification in the late Oligocene-Miocene followed by a slowdown in the rate of lineage accumulation over time. A parametric biogeographical reconstruction showed the importance of the southwest Pacific area, specifically the island arc of Fiji, Tonga, Vanuatu, Wallis, and Futuna, for diversification of Squat Lobsters, probably associated with the global warming, high tectonic activity, and changes in oceanic currents that took place in this region during the Oligocene-Miocene period. These results add strong evidence to the hypothesis that the Neogene was a period of major diversification for marine organisms in both shallow and deep waters.
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morphological and molecular description of new species of Squat Lobster crustacea decapoda galatheidae from the solomon and fiji islands south west pacific
Zoological Journal of the Linnean Society, 2009Co-Authors: Patricia Cabezas, Enrique Macpherson, Annie MachordomAbstract:The family Galatheidae is among the most diverse families of anomuran decapod crustaceans, and the South-West Pacific is a biodiversity hot spot for these Squat Lobsters. Attempts to clarify the taxonomic and evolutionary relationships of the Galatheidae on the basis of morphological and molecular data have revealed the existence of several cryptic species, differentiated only by subtle morphological characters. Despite these efforts, however, relationships among genera are poorly understood, and the family is in need of a detailed systematic review. In this study, we assess material collected in different surveys conducted in the Solomon Islands, as well as comparative material from the Fiji Islands, by examining both the morphology of the specimens and two mitochondrial markers (cytochrome oxidase subunit I, COI, and 16S rRNA). These two sources of data revealed the existence of eight new species of Squat Lobster, four of which were ascribed to the genus Munida, two to the genus Paramunida, one to the genus Plesionida, and the last species was ascribed to the genus Agononida. These eight species are described along with phylogenetic relationships at the genus level. Our findings support the taxonomic status of the new species, yet the phylogenetic relationships are not yet fully resolved. Further molecular analysis of a larger data set of species, and more conserved genes, will help clarify the systematics of this group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156, 465–493.