Ridley and Dendy, 1886
Definition: Growth forms include encrusting, facultative burrowing and excavating sponges, massive, or digitate growth forms, many with surface plates and sometimes with papillae protruding above the surface. Megascleres are tylostyles; microscleres are usually spirasters forming an ectosomal crust.
Remarks: 6 nominal genera and 4 valid genera are recognised.
Source: Hooper's Internet Sponge Guide
Genus represented in the area:
Spirastrella Schmidt, 1868 (type species S . cunctatrix Schmidt, 1868) (syn. Chondrillina de Laubenfels, 1936): encrusting, with characteristic veinal canal system (Spirastrella mollis), with a crust of normal spirasters and tylostyles in erect bundles.
Species included:
Spirastrella minax