Demosponge

Class of sponges

Demosponges or common sponges are sponges of the class Demospongiae (from Ancient Greek: δῆμος, romanized: dêmos, lit. 'common people' + σπογγιά, spongiá, 'sponge'), the most diverse group in the phylum Porifera which include greater than 90% of all extant sponges with nearly 8,800 species worldwide (according to the World Porifera Database). Being siliceous sponges, they are predominantly leuconoid in structure with an endoskeleton made of a meshwork of spicules consisting of fibers of the protein spongin, the mineral silica, or both. Where spicules of silica are present, they have a different shape from those in the otherwise similar glass sponges.

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