Nemanthidae with wide pedal disc, smooth column and long tentacles considerably fewer than the mesenteries at the base. Sphincter mesogloeal, well developed. Longitudinal muscles of tentacles and radial muscles of oral disc ectodermal. Actinopharynx with distinct, fairly broad siphonoglyphs, as a rule 2, but possibly variable in connection with asexual reproduction. Usually 2 pairs of directives. Perfect pairs of mesenteries 6-12, frequently irregularly arranged, so that the one side of the animal has more than the other, sterile. Stronger imperfect mesenteries fertile. Retractors of the mesenteries weak, parietobasilar muscles moderately weak or weak. Acontia-like organs "acontioids", considerably thicker than acontia and containing very few to rather few nematocysts of the same kind as in the filaments, present on at least some of the mesenteries. The individuals often live together in colonies sometimes so closely packed that the edges of their pedal discs touch each other intimately. Cnidom: spirocysts, basitrichs, microbasic p-mastigophors.
Sagartia nitidus Wassilieff 1908
N. annamensis Carlgren 1943
N. californicus Carlgren 1940
Definitions and contained taxa are those of Oscar Carlgren
as published in 1949 : Kungl Svenska Vetenskapsakadamiens Handlingar, Series
4, Volume 1, Number 1