Lake Bryozoan – Pectinatella sp.

Have you ever noticed a brownish, greenish, or highly transparent blob submerged at the edge of a lake or large pond? Most likely, it is a fascinating colonial member of a rather interesting phylum of animals Ė the phylum Bryozoa.

Individual bryozoans (zooids) are actually small worms with a circular (or horseshoe-shaped) rim of outstretched feeding tentacles at the head end. The structure is called the lophophore, making bryozoans one of the three main lophophorate phyla (the others are Brachiopoda and Phoronida). The feeding tentacles of the lophophore are covered with cilia, and theyre particularly effective at creating currents to bring small particulate food (such as bacteria) into the mouth of the worm.