Aquatic invertebrates belonging to the phylum Porifera having internal skeletons of silica or collagen, porous body around a cavity or cavities, and usually living in stationary communities.
Descriptions of sponges and examples of the deleterious effects of nonindigenous species, with links to distribution maps, species lists and related information on sponges.
U.S. Department of the Interior |
U.S. Geological Survey