Bryozoa

Phylum of colonial aquatic invertebrates called moss animals

The Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about 0.5 millimetres (1⁄64 in) long, they have a special feeding structure called a lophophore, a "crown" of tentacles used for filter feeding. The bryozoa are classified as the marine bryozoa (Stenolaemata), freshwater bryozoa (Phylactolaemata), and mostly-marine bryozoa (Gymnolaemata), a few members of which prefer brackish water.

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