What is "demosponge"

n. (context zoology English) Any sponge of the class ''Demospongiae''

Demospongiae is the most diverse class in the phylum Porifera. In fact, the demosponges include 81% of all species of sponges with nearly 7,000 species worldwide (World Porifera Database). They are predominantly leuconoid in structure. Their " skeletons" are made 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.

The many diverse orders in this class include all of the large sponges. Most are marine dwellers, but one order ( Spongillida) live in freshwater environments. Some species are brightly colored, with great variety in body shape; the largest species are over across. They reproduce both sexually and asexually.