Simplifying hydrozoan classification: inappropriateness of the group Hydroidomedusae in a phylogenetic context

Abstract

The systematics of Hydrozoa is considered from the viewpoint of logical consistency between phylogeny and classification. The validity of the nominal taxon Hydroidomedusae (including all groups of Hydrozoa except the Siphonophorae) is discussed with regard to its distinctness and inclusive relationships. In general, phylogenetic systematic evidence suggest that the use of the term Hydroidomedusae is inappropriate given our current level of understanding. It is concluded that no new, or resurrected, names are necessary before or until a broader phylogenetic revision of the Hydrozoa is accomplished.