From Encyclopedia Jr, free information reference for Kids
The Ectoprocta are a phylum of lophophorate animals. Formerly these animals made up one division of the Bryozoa, the other being the Entoprocta, which they superficially resemble. However, the Entoprocta are no longer thought to be closely related to the Ectoprocta, and are generally considered a phylum of their own. This leaves Ectoprocta as the only subgroup of Bryozoa: some researchers treat the two names as synonyms; others use Ectoprocta only.
Generally, the members of the ectoprocta phylum are colonial aquatic animals (also known as moss animals). Although the individual members are microscopic, colonies can grow up to one foot in length. They can reproduce both sexually and asexually. The Ectoprocta are one of the few classical phyla from which no members have been found in the Cambrian. They seem to have evolved in the Ordovician. Currently, there are about 5,000 living species in this phylum.