Spheciospongia

Diagnosis. Clionaid genus with mostly massive sponges (gamma- or delta-morphologies). Many species incorporating or agglutinating significant amounts of coarse sediment or shell and coral fragments. With ability to erode calcareous materials in contact with sponge, predominantly basally, as incorporated or agglutinated particles. Exhalants often wide, usually on elevated parts of body such as fistules. Inhalants often as pronounced sieve areas, often with spiraster crusts. Megascleres size-variable tylostyles and modifications (commonly as styles, tylostrongyles), usually two size classes, shorter class mostly restricted to ectosomal palisade. Tyle morphologies variable, but commonly weakly pronounced and longer than wide. Microscleres spirasters and derivates. Smallest, “rugose”, often amphiasterose forms as ectosomal crust. Longer, often helical forms largely restricted to choanosomal membranes and canal linings. Thicker spirasters with conical spines in some species, at the surface or throughout the choanosome.