SUBCLASS ASCOTHORACIDA LACAZE- DUTHIERS, 1880

Diagnosis: Bivalved crustaceans, with diverticula of midgut and gonads in carapace. Body generally with 11 free trunk segments, first six with biramous thoracopods, seventh with biramous or uniramous penis in both sexes (vestigial in females), last with moveable unsegmented furcal rami. Antennules four- to six-segmented, with claw guard and claw on terminal segment. Conical labrum surrounds piercing mouthparts. Parasites of echinoderms and anthozoans.

Comment: Grygier (1987a) provided a comprehensive review on the taxonomy of the Ascothoracida .