Theparabasalidsare a group of flagellatedprotistswithin supergroupExcavata. Most of these organisms form asymbioticrelationship inanimals; these include a variety of forms found in the intestines oftermitesand****roaches, many of which have symbioticbacteriathat help them digestcelluloseinwoody plants. Other species within this supergroup are knownparasites, and include humanpathogens.
The flagella are arranged in one or more clusters near the anterior of the cell. Theirbasal bodiesare linked toparabasal fibersthat attach to prominentGolgi complexes, distinctive to the group. Usually they also give rise to a sheet of cross-likemicrotubulesthat runs down the center of the cell and in some cases projects past the end. This is called theaxostyle, but is different in structure from the axostyles ofoxymonads.