Dimarcusidae

See text Dimarcusidae is a family of triclads found mostly in freshwater habitats of caves, although at least one species, Rhodax evelinae, occurs in surface waters.

[2] The family Dimarcusidae was erected in 1972 by Mitchell and Kawakatsu to include a new species, Dimarcus villalobosi.

However, the same species had been briefly described by Benazzi in the same year as Opisthobursa mexicana and this name had priority, with Dimarcus villalobosi becoming a junior synonym.

As a result, the family is called Dimarcusidae despite the absence of a valid genus Dimarcus.

[2] Recent molecular studies, however, suggest that Cavernicola is the sister group of Maricola, thus being more closely related to marine than to freshwater triclads.

Copulatory apparatus of Hausera hauseri showing the common ovovitelline duct (cod) perpendicular to the female genital duct (dgf)