Crustacea, the Higher Taxa

J.K. Lowry

Ascothoracida (Thecostraca, Maxillipoda)

Description. Head. Rostrum absent; eyes sessile or absent (in juvenile); compound, visual elements present (in juvenile cyprid stage); ocular scale absent; naupliar eyes present, or naupliar eyes absent (in nauplius stage). Antennules (antenna 1) uniramous; peduncle and flagellum indistinguishable; exopod well developed, whip-like or exopod prehensile. Antennae (antenna 2) reduced, vestigial or absent (in adult). Mouthparts modified to form suctorial cone. Thorax. Carapace present or absent, bivalved, enclosing head, body and appendages or enclosing head and thorax, laterally compressed, smooth. Thorax and abdomen differentiated or undifferentiated, with 3-6 pairs of appendages; biramous, or uniramous; peraeopods (legs) non-phyllopodous. Abdomen with 5 somites. Epimera absent. Pleopods absent. Uropods well developed, 1 pair, positioned terminally or subterminally; rami absent; claw-like. Telson absent.

Larval development. Embryos carried dorsally within the carapace.

Habitat. Marine ecto- and endoparasites of coelenterates and echinoderms.

Distribution. Worldwide.

Cite this publication as: Lowry, J.K. (1999 onwards). 'Crustacea, the Higher Taxa: Description, Identification, and Information Retrieval.' Version: 2 October 1999.