Gastrotricha

noun plural

Gas·​trot·​ri·​cha ga-ˈsträ-trə-kə 

: a small class or other taxon of minute freshwater multicellular animals that superficially resemble infusorians, have cilia on the ventral side, and are related to the rotifers with which they are included in the phylum Aschelminthes

gastrotrich

ˈgas-trə-ˌtrik 

noun