Gray, 1867
Definition: Encrusting to lobate-digitate growth forms. The surface often has a network of sculptured grooves or plates (Placospongia drawing), often closable, into which the ectosomal pores and oscules open. The plate-like grooves on the surface are rendered hard by a thick layer of closely packed sterrasters. A layer of upright tylostyles lies in the floor of each groove. Megascleres are tylostyles also occuring in tracts within the choanosomal skeleton. Microscleres are selenasters (sterraster-like, but derived from spirasters) forming both a dense surface crust and axial tracts, and silica may be pigmented red; in addition spirasters may be present (Placospongia decorticans).
Remarks: Only one Recent genus is known.
Source: Hooper's Internet Sponge Guide.
Genus represented in the area:
Placospongia Gray, 1867 (type species P . melobesioides Gray, 1867): characters of the family.
Species included:
Placospongia decorticans