views updated May 14 2018

Gastrotricha (phylum Aschelminthes) A small class (or phylum in some classifications) of microscopic, pseudo-coelomate worms in which an excretory system may be present. Some body areas are ciliated and the cuticle may have bristles. The worms occur in aquatic environments. Superficially they resemble Rotifera. There are about 150 known species.