Aplysinidae Carter, 1875

Diagnosis: Verongida with an anastomosing spongin skeleton of polygonal meshes, which have no tendency to be organized in one plane. The fibers have normal bark and pith elements, contain no foreign detritus and are of moderately even dimensions throughout the sponge. The choanocyte chambers are diplodal, small, and spherical, and are set in a dense collagenous matrix. All species display a marked oxidative colour change at death or on exposure to air, quickly changing from the normal yellow or yellow-green through blue to dark brown or purple. Pigmentation, other than superficial casts attributable to cyanobacteria, is uniform throughout the sponge. Secondary metabolites include a range of brominated tyrosine derivatives with strong antimicrobial activity. The sponges are oviparous and, while extrusion of gametes has been observed, no larvae have been described (Berquist & Cook, 2002).