|
Sponges in this class are typified by skeletal spicules composed of calcium carbonate. The spicules often protrude through the epipinecodermal covering of the body wall, giving the organism a rough texture. Calcareous sponges are small, usually only a few inches high, and are generally dull in appearance, although several species are brightly colored. Members of this class are among the simplest sponges, and all three morphological types : asconoid, syconoid, and leuconoid : are represented. There are approximately 150 known species, exclusively marine and shallow-water dwellers.
Sections in this article:
|