Dahms H.-U. 2004. Exclusion of the Polyarthra from Harpacticoida and its reallocation as an underived branch of the Copepoda (Arthropoda, Crustacea) // Invertebrate Zoology. Vol.1. No.1: 29–51 [in English].

Hong Kong University of Science and Technology/ Dept. Biology — Coastal Marine Lab/ Kowloon — Clearwater Bay/ Hong Kong/ SAR China.

Abstract: There is no reasonable autapomorphy, either from the naupliar or the adult organization, which justifies a monophylum Harpacticoida (sensu Lang, 1948). This implies a paraphyletic situation of this taxon, comprising two independent monophyletic taxa, the Polyarthra and the Oligoarthra. To solve this problem, the present study will provide justifying arguments for the exclusion of the taxon Polyarthra from the Harpacticoida, which then is exclusively represented by the monophylum Oligoarthra. When Polyarthra are excluded from the Harpacticoida, than Oligoarthra share the following naupliar synapomorphies: postmaxillar limbs widely spaced, antennal coxa with strong gnathobase, antennal endopodite elongate, mandibular endopodite an elongate process. Based on naupliar characters, Polyarthra are allocated as an underived taxon of the Copepoda, sharing with all other Copepoda the following naupliar characters: antennule 5-segmented, antennal exopodal segments increase from 6 at N I to a final number of 9 at N IV, antennal endopodite is 1-segmented, maxilla absent, swimming performance and life history, dorsocaudal process, antennule segment homologues, larger number of segments in naupliar antennal endo- and exopodites.

KEY WORDS: nauplii, development, phylogenetic systematics, ß-systematics, evolution, Polyarthra, Harpacticoida, Copepoda.

Download PDF