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In Worms Geoff Read NIWA New Zealand

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In Worms Geoff Read NIWA New Zealand Brussels, 28-30 September Polychaeta (Annelida) in WoRMS Geoff Read NIWA New Zealand www.marinespecies.org/polychaeta/index.php Context interface Swimming — an unexpected skill of Polychaeta Acrocirridae Alciopidae Syllidae Nereididae Teuthidodr ilus = squidworm Acrocirridae Polynoidae Swima bombiviridis Syllidae Total WoRMS Polychaeta records, excluding fossils 91 valid families. Entries >98% editor checked, except Echiura (69%) Group in WoRMS all taxa all species valid species names names names Class Polychaeta 23,872 20,135 11,615 Subclass Echiura 296 234 197 Echiura were recently a Subclass Errantia 12,686 10,849 6,210 separate phylum Subclass Polychaeta incertae sedis 354 265 199 Subclass Sedentaria 10,528 8,787 5,009 Non-marine Polychaeta 28 16 (3 terrestrial) Class Clitellata* 1601 1086 (279 Hirudinea) *Total valid non-leech clitellates~5000 spp, 1700 aquatic. (Martin et al. 2008) Annelida diversity "It is now clear that annelids, in addition to including a large number of species, encompass a much greater disparity of body plans than previously anticipated, including animals that are segmented and unsegmented, with and without parapodia, with and without chaetae, coelomate and acoelomate, with straight guts and with U-shaped digestive tracts, from microscopic to gigantic." (Andrade et al. 2015) Andrade et al (2015) “Articulating “archiannelids”: Phylogenomics and annelid relationships, with emphasis on meiofaunal taxa.” Molecular Biology and Evolution, efirst Myzostomida (images Summers et al)EV Nautilus: Riftia Semenov: Terebellidae Annelida latest phylogeny “… it is now well accepted that Annelida includes many taxa formerly considered different phyla or with supposed affiliations with other animal groups, such as Sipuncula, Echiura, Pogonophora and Vestimentifera, Myzostomida, or Diurodrilida (Struck et al. 2011; Kvist and Siddall 2013; Weigert et al. 2014; Andrade et al. 2015; Laumer et al. 2015a; Struck et al. 2015).” Giribet, G. (2015) New animal phylogeny: future challenges for animal phylogeny in the age of phylogenomics. Organisms Diversity & Evolution, efirst, 1-8. Myzostomida (images Summers et al) Higher & higher ranks: the collapse of Pogonophora etc into family Siboglinidae In 2001 Rouse distilled two phyla (Pogonophora, Vestimentifera), as well as two subphyla, three classes, and 13 families down into family Siboglinidae What has happened since? Nothing adverse … deep-sea siboglinid research continues apace Currently there are 32 siboglinid genera and just 178 species State of play — current WoRMS Polychaeta ad hoc hierarchy Subclass Echiura Subclass Polychaeta incertae sedis Subclass Errantia Suborder Aphroditiformia Order Amphinomida Suborder Glyceriformia Order Eunicida Order Phyllodocida Suborder Nereidiformia Suborder Phyllodociformia Suborder Phyllodocida incertae sedis Subclass Sedentaria Order Sabellida Infraclass Canalipalpata Order Spionida Family Chaetopteridae Order Terebellida Infraclass Scolecida outgroups Annelida latest phylogeny Fig. 5 ML tree. Andrade et al (2015) First-split annelids “Articulating “archiannelids”: Phylogenomics and annelid relationships, with emphasis on Sipuncula meiofaunal taxa.” Molecular Biology and Evolution, efirst. Myzostomida Where or what is 'Polychaeta' now? Errantia Is it a superfluous name? Is it Errantia plus Sedentaria, which latter Sedentaria includes Clitellates (oligochaetes & hirudinea) Echiura plus Echiura? Clitellata Myzostomida (images Summers et al)Siboglinidae Planning ahead … Annelidabase? Discuss with colleagues? Planning ahead … Annelidabase? Discuss with colleagues? Annelida Annelida Annelida Brussels, 28-29-30 September < Ends > Sabella spallanzanii by C. Middleton .
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