Family Tethyidae Gray, 1848

Abstract

Tethyidae Gray (Demospongiae, Hadromerida) includes sponges with stylote megascleres and two types of asters: micrasters and megasters. The body shape is typically globose but also irregularly massive or encrusting, and in some genera is supported by a stalk. The surface is verrucose with tubercles. A cortex is frequently more-or-less developed around a softer choanosomal core. The skeleton struc-ture is usually made by radiate bundles of stylote megascleres (strongyloxeas). The type genus Tethya contains the greatest number of species but the family contains 14 valid genera and approximately 80 described species distributed worldwide, in tropical, temperate seas and one species in the arctic. They are mainly found in shallow waters but also occasionally in the deep-sea. Genera are differentiated essentially on the basis of their skeletal structure, which may determine changes in the body shape and spicular types.