Phylogeny of the Diopatra generic complex with a revision of Paradiopatra Ehlres, 1887 (Polychaeta: Onuphidae)

Abstract

Analysis of 55 morphological characters yielded a phylogenetic reconstruction of the Diopatra complex, currently including three genera (Diopatra, Epidiopatra, and Paradiopatra). The results reject the monophyletic status of the complex and all three genera analysed. It is suggested that several parallel and independent events of paedomorphic evolution took place within the genera Diopatra and Paradiopatra, which led to the recognition of two artificial genera Epidiopatra and Notonuphis. The following taxonomic revisions are proposed: (1) Epidiopatra as a junior synonym of Diopatra; (2) Notonuphis as a junior synonym of Paradiopatra; (3) the Diopatra complex, consisting of two sister genera Diopatra and Paradiopatra, and two basal genera Paxtonia gen. nov. and Protodiopatra gen. nov., erected for two species previously included in Paradiopatra. Reconstruction of phylogenetic relationships within Paradiopatra yields a few reliable clades comprising well-defined groups of species, but supported by homoplastic synapomorphies representing highly adaptive characters. Twenty-six valid species of Paradiopatra, including a new species, Paradiopatra pyricirra sp. nov., are described or re-described and illustrated based on original descriptions and re-examination of type and non-type material. Identification keys to genera included in the Diopatra complex, and to all accepted Paradiopatra species, are presented. © 2011 The Linnean Society of London.