Family EPISTYLIDIDAE Kahl, 1933

Syn.	Epistylidae - a misspelling all too commonly used!

Generally stalked, with stalk often noncontractile (but body may be highly contractile); solitary or colonial; great range in sizes [some species of two genera (Campanella, Epistylis) may have zooids up to 600 µm]; abundant in fresh-water habitats (occasionally marine), free or as symphorionts associated with diverse hosts - from other peritrichs to molluscs, crustaceans (barnacle to crab and crayfish: body or gills), aquatic insects, lower vertebrates, etc. - with one genus (Apiosoma) especially widely found on the integument of fresh-water fishes.

Apiosoma Blanchard, 1885 (syn. Glossatella). Many species.
Campanella Goldfuss, 1820. Few species.
Epistylis Ehrenberg, 1830 (syns. Allomeron, Nidula, Orthochona). Very many (ca. 100) species.
Opisthostyla Stokes, 1886. Several species.
Rhabdostyla Kent, 1881. Many to very many species.
Incertae sedis:
Systylis Bresslau, 1919. Single species.