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Tharina Louise Bird - One of the best experts on this subject based on the ideXlab platform.
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Cheliceral morphology of Solifugae (Arachnida): Primary homology, terminology, and character survey
Bulletin of the American Museum of Natural History, 2015Co-Authors: Tharina Louise BirdAbstract:ABSTRACT Arachnids of the order Solifugae (solifuges, false spiders, sun spiders, camel spiders, Walzenspinne, wind spiders) possess the largest jaws for body size among the Chelicerata. The chelicerae provide the most important character systems for solifuge systematics, including dentition and the male cheliceral flagellum, both used extensively for species delimitation and diagnosis. However, the terminology used for cheliceral characters is not standardized and often contradictory, in part because it fails to represent homologous structures among taxa. Misinterpretation of character homology may introduce errors in phylogenetic analyses concerning relationships within Solifugae and among the orders of Chelicerata. This contribution presents the first comprehensive analysis of cheliceral morphology across the order Solifugae, the aims of which were to provide a broad survey of cheliceral characters for solifuge systematics, to identify and reinterpret structures based on primary homology, to revise the...
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High resolution images for 'Cheliceral morphology in Solifugae (Arachnida) : primary homology, terminology, and character survey. (Bulletin of the American Museum of Natural History, no. 394)'
American Museum of Natural History Research Library, 2015Co-Authors: Lorenzo Prendini, Robert A. Wharton, Tharina Louise BirdAbstract:355 pages : illustrations (some color) ; 26 cm.Arachnids of the order Solifugae (solifuges, false spiders, sun spiders, camel spiders, Walzenspinne, wind spiders) possess the largest jaws for body size among the Chelicerata. The chelicerae provide the most important character systems for solifuge systematics, including dentition and the male cheliceral flagellum, both used extensively for species delimitation and diagnosis. However, the terminology used for cheliceral characters is not standardized and often contradictory, in part because it fails to represent homologous structures among taxa. Misinterpretation of character homology may introduce errors in phylogenetic analyses concerning relationships within Solifugae and among the orders of Chelicerata. This contribution presents the first comprehensive analysis of cheliceral morphology across the order Solifugae, the aims of which were to provide a broad survey of cheliceral characters for solifuge systematics, to identify and reinterpret structures based on primary homology, to revise the terminology to be consistent with homology hypotheses, and to provide a guide to terminological synonyms and character interpretations in the literature. Chelicerae were studied in 188 exemplar species (17% of the total), representing all 12 solifuge families, 17 of the 19 subfamilies, 64 genera (46% of the total), and the full range of variation in cheliceral morphology across the order. In total, 157 species representing 49 genera and 17 subfamilies are illustrated. Hypotheses of character transformation, particularly concerning the male flagellum, and a standardized terminology, are presented. The functional morphology of the chelicerae is discussed and the role of sexually dimorphic modifications to the male chelicerae in mating behavior emphasized. The revised terminology, based on hypotheses of primary homology, will facilitate solifuge revisionary systematics and provide a stronger basis for reconstructing phylogenetic relationships within the order Solifugae and testing the phylogenetic position of the order within Chelicerata
Prashant P Sharma - One of the best experts on this subject based on the ideXlab platform.
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Developmental gene expression as a phylogenetic data class: support for the monophyly of Arachnopulmonata
Development Genes and Evolution, 2020Co-Authors: Erik D. Nolan, Carlos E. Santibáñez-lópez, Prashant P SharmaAbstract:Despite application of genome-scale datasets, the phylogenetic placement of scorpions within arachnids remains contentious between two different phylogenetic data classes. Paleontologists continue to recover scorpions in a basally branching position, partly owing to their morphological similarity to extinct marine orders like Eurypterida (sea scorpions). Phylogenomic datasets consistently recover scorpions in a derived position, as the sister group of Tetrapulmonata (a clade of arachnids that includes spiders). To adjudicate between these hypotheses using a rare genomic change (RGC), we leveraged the recent discovery of ancient paralogy in spiders and scorpions to assess phylogenetic placement. We identified homologs of four transcription factors required for appendage patterning ( dachshund , homothorax , extradenticle , and optomotor blind ) in arthropods that are known to be duplicated in spiders. Using genomic resources for a spider, a scorpion, and a harvestman, we conducted gene tree analyses and assayed expression patterns of scorpion gene duplicates. Here we show that scorpions, like spiders, retain two copies of all four transcription factors, whereas arachnid orders like mites and harvestmen bear a single copy. A survey of embryonic expression patterns of the scorpion paralogs closely matches those of their spider counterparts, with one paralog consistently retaining the putatively ancestral pattern found in the harvestman, as well as the mite, and/or other outgroups. These data comprise a rare genomic change in chelicerate phylogeny supporting the inference of a distal placement of scorpions. Beyond demonstrating the diagnostic power of developmental genetic data as a phylogenetic data class, a derived placement of scorpions within the arachnids, together with an array of stem-group Paleozoic scorpions that occupied marine habitats, effectively rules out a scenario of a single colonization of terrestrial habitat within Chelicerata, even in tree topologies contrived to recover the monophyly of Arachnida.
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Chelicerates.
Current biology : CB, 2018Co-Authors: Prashant P SharmaAbstract:Compared to other arthropods, such as crustaceans or insects, the term 'chelicerate' often does not evoke a similar sense of recognition or familiarity. Yet the subphylum Chelicerata has been encountered by every living person today, frequently to the effect of fear, awe, or outright revulsion. Chelicerates include such familiar groups as spiders, scorpions, mites, and ticks, as well as an array of bizarre and unfamiliar forms, such as vinegaroons, camel spiders, and hooded tick spiders (Figure 1).
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A rticle Phylogenomic Interrogation of Arachnida Reveals Systemic Conflicts in Phylogenetic Signal
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo Giribet, Associate Nicolas VidalAbstract:Chelicerata represents one of the oldest groups of arthropods, with a fossil record extending to the Cambrian, and is sister group to the remaining extant arthropods, the mandibulates. Attempts to resolve the internal phylogeny of chelicerates have achieved little consensus, due to marked discord in both morphological and molecular hypotheses of chelicerate phylogeny. Themonophyly of Arachnida, the terrestrial chelicerates, is generally accepted, but has garnered little support from molecular data, which have been limited either in breadth of taxonomic sampling or in depth of sequencing. To address the internal phylogeny of this group, we employed a phylogenomic approach, generating transcriptomic data for 17 species in combination with existing data, including two complete genomes. We analyzed multiple data sets contain-ing up to 1,235,912 sites across 3,644 loci, using alternative approaches to optimization of matrix composition. Here, we show that phylogenetic signal for the monophyly of Arachnida is restricted to the 500 slowest-evolving genes in the data set. Accelerated evolutionary rates in Acariformes, Pseudoscorpiones, and Parasitiformes potentially engender long-branch attraction artifacts, yielding nonmonophyly of Arachnida with increasing support upon incrementing the number of concatenated genes. Mutually exclusive hypotheses are supported by locus groups of variable evolutionary rate, revealing significant conflicts in phylogenetic signal. Analyses of gene-tree discordance indicate marked incongru-ence in relationships among chelicerate orders, whereas derived relationships are demonstrably robust. Consistentl
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Frontinella communis Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Frontinella communes (Chelicerata: Araneae) Trinity assembl
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Metasiro americanus Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Metasiro americanus (Chelicerata: Opiliones) Trinity assembl
Gonzalo Giribet - One of the best experts on this subject based on the ideXlab platform.
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A rticle Phylogenomic Interrogation of Arachnida Reveals Systemic Conflicts in Phylogenetic Signal
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo Giribet, Associate Nicolas VidalAbstract:Chelicerata represents one of the oldest groups of arthropods, with a fossil record extending to the Cambrian, and is sister group to the remaining extant arthropods, the mandibulates. Attempts to resolve the internal phylogeny of chelicerates have achieved little consensus, due to marked discord in both morphological and molecular hypotheses of chelicerate phylogeny. Themonophyly of Arachnida, the terrestrial chelicerates, is generally accepted, but has garnered little support from molecular data, which have been limited either in breadth of taxonomic sampling or in depth of sequencing. To address the internal phylogeny of this group, we employed a phylogenomic approach, generating transcriptomic data for 17 species in combination with existing data, including two complete genomes. We analyzed multiple data sets contain-ing up to 1,235,912 sites across 3,644 loci, using alternative approaches to optimization of matrix composition. Here, we show that phylogenetic signal for the monophyly of Arachnida is restricted to the 500 slowest-evolving genes in the data set. Accelerated evolutionary rates in Acariformes, Pseudoscorpiones, and Parasitiformes potentially engender long-branch attraction artifacts, yielding nonmonophyly of Arachnida with increasing support upon incrementing the number of concatenated genes. Mutually exclusive hypotheses are supported by locus groups of variable evolutionary rate, revealing significant conflicts in phylogenetic signal. Analyses of gene-tree discordance indicate marked incongru-ence in relationships among chelicerate orders, whereas derived relationships are demonstrably robust. Consistentl
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Pseudocellus sp. Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Pseudocellus sp. (Chelicerata: Ricinulei) Trinity assembl
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Frontinella communis Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Frontinella communes (Chelicerata: Araneae) Trinity assembl
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Metasiro americanus Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Metasiro americanus (Chelicerata: Opiliones) Trinity assembl
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Siro boyerae Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Siro boyerae (Chelicerata: Opiliones) Trinity assembl
Ward C. Wheeler - One of the best experts on this subject based on the ideXlab platform.
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A rticle Phylogenomic Interrogation of Arachnida Reveals Systemic Conflicts in Phylogenetic Signal
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo Giribet, Associate Nicolas VidalAbstract:Chelicerata represents one of the oldest groups of arthropods, with a fossil record extending to the Cambrian, and is sister group to the remaining extant arthropods, the mandibulates. Attempts to resolve the internal phylogeny of chelicerates have achieved little consensus, due to marked discord in both morphological and molecular hypotheses of chelicerate phylogeny. Themonophyly of Arachnida, the terrestrial chelicerates, is generally accepted, but has garnered little support from molecular data, which have been limited either in breadth of taxonomic sampling or in depth of sequencing. To address the internal phylogeny of this group, we employed a phylogenomic approach, generating transcriptomic data for 17 species in combination with existing data, including two complete genomes. We analyzed multiple data sets contain-ing up to 1,235,912 sites across 3,644 loci, using alternative approaches to optimization of matrix composition. Here, we show that phylogenetic signal for the monophyly of Arachnida is restricted to the 500 slowest-evolving genes in the data set. Accelerated evolutionary rates in Acariformes, Pseudoscorpiones, and Parasitiformes potentially engender long-branch attraction artifacts, yielding nonmonophyly of Arachnida with increasing support upon incrementing the number of concatenated genes. Mutually exclusive hypotheses are supported by locus groups of variable evolutionary rate, revealing significant conflicts in phylogenetic signal. Analyses of gene-tree discordance indicate marked incongru-ence in relationships among chelicerate orders, whereas derived relationships are demonstrably robust. Consistentl
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Pseudocellus sp. Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Pseudocellus sp. (Chelicerata: Ricinulei) Trinity assembl
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Frontinella communis Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Frontinella communes (Chelicerata: Araneae) Trinity assembl
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Metasiro americanus Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Metasiro americanus (Chelicerata: Opiliones) Trinity assembl
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Siro boyerae Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Siro boyerae (Chelicerata: Opiliones) Trinity assembl
Stefan T. Kaluziak - One of the best experts on this subject based on the ideXlab platform.
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A rticle Phylogenomic Interrogation of Arachnida Reveals Systemic Conflicts in Phylogenetic Signal
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo Giribet, Associate Nicolas VidalAbstract:Chelicerata represents one of the oldest groups of arthropods, with a fossil record extending to the Cambrian, and is sister group to the remaining extant arthropods, the mandibulates. Attempts to resolve the internal phylogeny of chelicerates have achieved little consensus, due to marked discord in both morphological and molecular hypotheses of chelicerate phylogeny. Themonophyly of Arachnida, the terrestrial chelicerates, is generally accepted, but has garnered little support from molecular data, which have been limited either in breadth of taxonomic sampling or in depth of sequencing. To address the internal phylogeny of this group, we employed a phylogenomic approach, generating transcriptomic data for 17 species in combination with existing data, including two complete genomes. We analyzed multiple data sets contain-ing up to 1,235,912 sites across 3,644 loci, using alternative approaches to optimization of matrix composition. Here, we show that phylogenetic signal for the monophyly of Arachnida is restricted to the 500 slowest-evolving genes in the data set. Accelerated evolutionary rates in Acariformes, Pseudoscorpiones, and Parasitiformes potentially engender long-branch attraction artifacts, yielding nonmonophyly of Arachnida with increasing support upon incrementing the number of concatenated genes. Mutually exclusive hypotheses are supported by locus groups of variable evolutionary rate, revealing significant conflicts in phylogenetic signal. Analyses of gene-tree discordance indicate marked incongru-ence in relationships among chelicerate orders, whereas derived relationships are demonstrably robust. Consistentl
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Pseudocellus sp. Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Pseudocellus sp. (Chelicerata: Ricinulei) Trinity assembl
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Frontinella communis Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Frontinella communes (Chelicerata: Araneae) Trinity assembl
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Metasiro americanus Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Metasiro americanus (Chelicerata: Opiliones) Trinity assembl
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Siro boyerae Trinity assembly
2016Co-Authors: Prashant P Sharma, Stefan T. Kaluziak, Alicia R. Perez-porro, Vanessa L. Gonzalez, Gustavo Hormiga, Ward C. Wheeler, Gonzalo GiribetAbstract:Siro boyerae (Chelicerata: Opiliones) Trinity assembl