Phylogenetic Taxonomy, a Farewell to Species, and a Revision of Heteropodarke (Hesionidae, Polychaeta, Annelida)

Abstract

Cladistic relationships between 7 parts of the hesionid polychaete group Heteropodarke are assessed in a parsimony analysis based on 34 morphological characters. Taxon names are de- fined by apomorphy-based phylogenetic definitions, without reference to Linnean ranks or types. Species entities are omitted and denied any role in taxonomy; taxon names refer to monophyletic groups only. Linnean binomial species names are not employed, and all taxa are assigned uninomi- als. Previously known parts of Heteropodarke (Africana Hartmann-Schroder, 1974; Formalis, Perkins, 1984; Heteromorpha Hartmann-Schroder, 1962; Lyonsi Perkins, 1984; Xiamenensis Ding, Wu, and Wes- theide, 1997) are reexamined, and Bidentata, new taxon, and Zmyrina (informal name) are de- scribed from Papua New Guinea and Belize, respectively. The new taxon Crassichaetae is named for a subgroup of Heteropodarke, which is diagnosed by enlarged, anteriorly situated falcigers, and in- cludes Africana, Heteromorpha, Lyonsi, and Xiamenensis . Within this group Africana and Heteromorpha are treated as taxa inquirendae. {Apomorphy-based definitions; Linnean nomenclature; phylogenetic taxonomy; polychaetes; ranks; species concepts; species names; types.}