Phylum: Porifera
Class: Demospongia (Sollas, 1885)
Cincinnatian Orders: Lithistida

Geologic Range
Cambrian – Recent

Common Paleoecology
Demospongia is an extant class of stationary intermediate-level epifaunal suspension feeders

Characteristics of the Class

  • Composed of siliceous spicules, spicules and spongin, or spongin alone
  • Spicules tetraxons or derivatives with fewer rays
  • Can have foreign inclusions

Published Descriptions

Reid (1963):

  • Gelatinosa with siliceous spicules, siliceous spicules and spongin, spongin alone, or no skeleton. Spicules tetraxons or derivatives with more or fewer rays. Megascleres and microscleres differentiated except in primitive examples; many forms with megascleres only, due to loss of the microscleres; some with microscleres only.

Treatise on Invertebrate Paleontology, Part E (1955):

  • Architecture compact rhagon. Siliceous spicules, or spongin, or (commonly) both, or (rarely) neither present. Diverse sorts of foreign inclusions occur in many.