sea fan, colonial marine animal forming erect, flattened, branching colonies in tropical and subtropical waters. Colonies may be several feet high and are often colorful, with purples, reds, and yellows predominating. The individuals, or polyps (see polyp and medusa), have eight feathery tentacles and feed on plankton organisms. Sea fans are classified in the phylum Cnidaria, class Anthozoa, order Gorgonacea.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
More on sea fan from Fact Monster:
See more Encyclopedia articles on: Zoology: Invertebrates