Phylum - Mollusca
(Gastropods, Cephalopods, & Bivalvia)

The mollusks are the large and diverse phylum Mollusca, which includes a variety of familiar animals well known for their decorative shells or as seafood. These range from tiny snails, clams, and abalone to squid, cuttlefish and the octopus (which is considered the most intelligent invertebrate). There are some 112,000 species within this phylum.The giant squid, which until recently had not been observed alive in its adult form, is the largest invertebrate; although it is possible that the colossal squid is even larger.

Giant clam: Photographed by Jan Derk in November 2002 on the Great Barrier Reef, Australia.Octopus: Photographed by Luis Miguel Bugallo Sánchez