Family Corallistidae Sollas, 1888

Abstract

Corallistidae (Demospongiae, ‘lithistids’) contains four extant genera (two described as new) with about 20 nominal (mostly poorly known) species distributed worldwide. Corallistidae are known at least since the Late Jurassic and have numerous representatives in the fossil record. Today they live, as do most ‘lithistids’, in deeper waters, showing cup, vase, lamellar, club or massive shaped habits. Desmas are monaxial, strongly tuberculated large dicranoclones which articulate with main body of other dicranoclones (non-terminal articula- tion). Ectosomal megascleres are smooth or spinose dichotriaenes, sometimes also triaenes; other megascleres may be oxeas. Microscleres are streptasters (often two types of spirasters), and/or microxeas, microrhabds or microstyles. Differentiation is based mostly on the type of ectosomal dichotriaenes and microscleres, as well as habitus.