Artículos de revistas
Articulating “Archiannelids”: phylogenomics and annelid relationships, with emphasis on meiofaunal taxa
Fecha
2015Autor
Andrade, Sonia Cristina da Silva
Novo, Marta
Kawauchi, Gisele Yukimi
Worsaae, Katrine
Pleijel, Fredrik
Giribet, Gonzalo
Rouse, Greg W.
Institución
Resumen
Annelid morphological disparity has resulted in morphological-based classifications that disagree with phylogenies based on Sanger sequencing and phylogenomic analyses. However, the data used for the latter studies came from various sources and technologies, involved poorly-occupied matrices and lacked key lineages. Here we generated a new Illumina-based dataset to address annelid relationships from a fresh perspective, independent from previously generated data and with nearly fully-occupied matrices. Our sampling reflects the span of annelid diversity, including two symbiotic annelid groups (Myzostomida and Spinther) and five meiofaunal groups once referred to as part of Archiannelida (three from Protodrilida, plus Dinophilus and Polygordius). As well as the placement of these unusual annelids, we sought to address the overall phylogeny of Annelida, and provide a new perspective for naming of major clades. Our results largely corroborate the phylogenomic results of Weigert et al. (2014), with “Magelona + Owenia” and Chaetopteridae forming a grade with respect to all other annelids. Echiura and Sipuncula are supported as being annelid groups, with Sipuncula closest to amphinomids as sister group to Sedentaria and Errantia. We recovered the three Protodrilida terminals as sister clade to Phyllodocida and Eunicida (= clade Aciculata). We therefore place Protodrilida as part of Errantia. Polygordius was found to be sister group to the scaleworm terminal and the possibility that it is a simplified scaleworm clade, as has been shown for the former family Pisionidae, is discussed. Our results were equivocal with respect to Dinophilus, Myzostomida and Spinther possibly owing to confounding long-branch effects.