Article
Article
Ascothoracica
Article By:
Stubbings, H. G. Admiralty Materials Laboratory, Poole, United Kingdom.
Last reviewed:October 2019
DOI:https://doi.org/10.1036/1097-8542.054500
A subtaxon of marine crustaceans in the subclass Thecostraca. Members of the Ascothoracica are ectoparasites or endoparasites of cnidarians and echinoderms. The body is enclosed in a voluminous saclike mantle that is up to 20 mm (0.8 in.) in length; the body itself is only about one-fourth of this length (see illustration). Ascothoracicans are not attached permanently to the host by the antennular region, but the antennules may be modified as a clasping organ. The mouthparts are also modified as a clasping organ and for piercing and sucking. Up to six pairs of thoracic appendages are present, which are reduced in number and development in the endoparasites. Individuals of the Ascothoracica retain a more or less segmented abdomen in the adult. There are no cement glands. Diverticula of the alimentary canal extend into the mantle.
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