The Phylum Ectoprocta (also called Bryozoa) consists of small, colonial, aquatic invertebrates commonly known as bryozoans or “moss animals.” They live mostly in marine environments, though some are freshwater. Each individual, called a zooid, is tiny and lives within a protective exoskeletal chamber, but colonies function as a single unit. Ectoprocts are sessile filter feeders, using a crown of ciliated tentacles called a lophophore to capture plankton from water. They reproduce both sexually and asexually and play important roles in aquatic ecosystems as reef builders and habitat providers.