Thenaria (Acontiaria) without sphincter. Mesenteries divisible into macro- and microcnemes. Acontia with basitrichs and probably microbasic amastigophors.
Definitions and contained taxa are those of Oscar Carlgren as published in 1949 : Kungl Svenska Vetenskapsakadamiens Handlingar, Series 4, Volume 1, Number 1
Electronic version made possible by NSF grant DEB95-21819 in the PEET program to D. G. Fautin.