Demospongiae (Demospongea; phylum Porifera) A class of sponges which occur in both marine and freshwater environments. They have a leucon body structure. Both siliceous spicules and organic fibres may form a skeleton, but primitive types may lack skeletal support. This is the largest group of sponges and it first appeared in the Cambrian.
Demospongiae See DEMOSPONGEA.
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