19 research outputs found

    Managing Heterogeneous Models and Schemas in the

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    Managing models and schemas pertaining to different parts of the marine information domain is an important part of the U.S. Coast Guard R&D Center's proposed Waterway Information Network. This paper describes our approach to distributed model and schema management and an architecture for facilitating the use of formal artificial intelligence concepts in application development with XML

    A new classification of Carex (Cyperaceae) subgenera supported by a HybSeq backbone phylogenetic tree

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    The field of systematics is experiencing a new molecular revolution driven by the increased availability of high-throughput sequencing technologies. As these techniques become more affordable, the increased genomic resources have increasingly far-reaching implications for our understanding of the Tree of Life. With c. 2000 species, Carex (Cyperaceae) is one of the five largest genera of angiosperms and one of the two largest among monocots, but the phylogenetic relationships between the main lineages are still poorly understood. We designed a Cyperaceae-specific HybSeq bait kit using transcriptomic data of Carex siderosticta and Cyperus papyrus. We identified 554 low-copy nuclear orthologous loci, targeting a total length of c. 1 Mbp. Our Cyperaceae-specific kit shared loci with a recently published angiosperm-specific Anchored Hybrid Enrichment kit, which enabled us to include and compile data from different sources. We used our Cyperaceae kit to sequence 88 Carex spp., including samples of all the five major clades in the genus. For the first time, we present a phylogenetic tree of Carex based on hundreds of loci (308 nuclear exon matrices, 543 nuclear intron matrices and 66 plastid exon matrices), demonstrating that there are six strongly supported main lineages in Carex: the Siderostictae, Schoenoxiphium, Unispicate, Uncinia, Vignea and Core Carex clades. Based on our results, we suggest a revised subgeneric treatment and provide lists of the species belonging to each of the subgenera. Our results will inform future biogeographic, taxonomic, molecular dating and evolutionary studies in Carex and provide the step towards a revised classification that seems likely to stand the test of time

    A new classification of Carex (Cyperaceae) subgenera supported by a HybSeq backbone phylogenetic tree

    No full text
    The field of systematics is experiencing a new molecular revolution driven by the increased availability of high-throughput sequencing technologies. As these techniques become more affordable, the increased genomic resources have increasingly far-reaching implications for our understanding of the Tree of Life. With c. 2000 species, Carex (Cyperaceae) is one of the five largest genera of angiosperms and one of the two largest among monocots, but the phylogenetic relationships between the main lineages are still poorly understood. We designed a Cyperaceae-specific HybSeq bait kit using transcriptomic data of Carex siderosticta and Cyperus papyrus. We identified 554 low-copy nuclear orthologous loci, targeting a total length of c. 1 Mbp. Our Cyperaceae-specific kit shared loci with a recently published angiosperm-specific Anchored Hybrid Enrichment kit, which enabled us to include and compile data from different sources. We used our Cyperaceae kit to sequence 88 Carex spp., including samples of all the five major clades in the genus. For the first time, we present a phylogenetic tree of Carex based on hundreds of loci (308 nuclear exon matrices, 543 nuclear intron matrices and 66 plastid exon matrices), demonstrating that there are six strongly supported main lineages in Carex: the Siderostictae, Schoenoxiphium, Unispicate, Uncinia, Vignea and Core Carex clades. Based on our results, we suggest a revised subgeneric treatment and provide lists of the species belonging to each of the subgenera. Our results will inform future biogeographic, taxonomic, molecular dating and evolutionary studies in Carex and provide the step towards a revised classification that seems likely to stand the test of time

    Making 'Carex' monophyletic (Cyperaceae, tribe Cariceae): a new broader circumscription

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    'Carex' (Cyperaceae), with an estimated 2000 species, nearly cosmopolitan distribution and broad range of habitats, is one of the largest angiosperm genera and the largest in the temperate zone. In this article, we provide argument and evidence for a broader circumscription of 'Carex' to add all species currently classified in 'Cymophyllus' (monotypic), 'Kobresia' (c. 60 species), 'Schoenoxiphium' (c. 15 species) and 'Uncinia' (c. 70 species) to those currently classified as 'Carex'. 'Carex' and these genera comprise tribe Cariceae (subfamily Cyperoideae, Cyperaceae) and form a wellsupported monophyletic group in all molecular phylogenetic studies to date. 'Carex' as defined here in the broad sense currently comprises at least four clades. Three are strongly supported ('Siderostictae', core 'Vignea' and core 'Carex'), whereas the caricoid clade, which includes all the segregate genera, receives only weak to moderate support. The caricoid clade is most commonly split into two clades, one including a monophyletic Schoenoxiphium and two small clades of species of 'Carex s.s.', and the other comprising 'Kobresia', 'Uncinia' and mostly unispicate species of 'Carex s.s.' Morphological variation is high in all but the 'Vignea' clade, making it extremely difficult to define consistent synapomorphies for most clades. However, 'Carex s.l.' as newly circumscribed here is clearly differentiated from the sister groups in tribe Scirpeae by the transition from bisexual flowers with a bristle perianth in the sister group to unisexual flowers without a perianth in 'Carex'. The naked female flowers of 'Carex s.l.' are at least partially enclosed in a flask-shaped prophyll, termed a perigynium. 'Carex s.s.' is not only by far the largest genus in the group, but also the earliest published name. As a result, only 72 new combinations and 58 replacement names are required to treat all of tribe Cariceae as a single genus 'Carex'. We present the required transfers here, with synonymy, and we argue that this broader monophyletic circumscription of 'Carex' reflects the close evolutionary relationships in the group and serves the goal of nomenclatural stability better than other possible treatments

    Making Carex monophyletic (Cyperaceae, tribe Cariceae): a new broader circumscription

    No full text
    Carex (Cyperaceae), with an estimated 2000 species, nearly cosmopolitan distribution and broad range of habitats, is one of the largest angiosperm genera and the largest in the temperate zone. In this article, we provide argument and evidence for a broader circumscription of Carex to add all species currently classified in Cymophyllus (monotypic), Kobresia (c. 60 species), Schoenoxiphium (c. 15 species) and Uncinia (c. 70 species) to those currently classified as Carex. Carex and these genera comprise tribe Cariceae (subfamily Cyperoideae, Cyperaceae) and form a well-supported monophyletic group in all molecular phylogenetic studies to date. Carex as defined here in the broad sense currently comprises at least four clades. Three are strongly supported (Siderostictae, core Vignea and core Carex), whereas the caricoid clade, which includes all the segregate genera, receives only weak to moderate support. The caricoid clade is most commonly split into two clades, one including a monophyletic Schoenoxiphium and two small clades of species of Carex s.s., and the other comprising Kobresia, Uncinia and mostly unispicate species of Carex s.s. Morphological variation is high in all but the Vignea clade, making it extremely difficult to define consistent synapomorphies for most clades. However, Carex s.l. as newly circumscribed here is clearly differentiated from the sister groups in tribe Scirpeae by the transition from bisexual flowers with a bristle perianth in the sister group to unisexual flowers without a perianth in Carex. The naked female flowers of Carex s.l. are at least partially enclosed in a flask-shaped prophyll, termed a perigynium. Carex s.s. is not only by far the largest genus in the group, but also the earliest published name. As a result, only 72 new combinations and 58 replacement names are required to treat all of tribe Cariceae as a single genus Carex. We present the required transfers here, with synonymy, and we argue that this broader monophyletic circumscription of Carex reflects the close evolutionary relationships in the group and serves the goal of nomenclatural stability better than other possible treatments.(c) 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179, 1-42
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