Brinkhurst, 1985
Type species Naidium bilobatum Bretscher, 1903
Number of species at least 17. Seven species known from NWE:
Pristinella amphibiotica (Lastockin, 1927)
Pristinella bilobata (Bretscher, 1903)
Pristinella jenkinae (Stephenson, 1931)
Pristinella menoni (Aiyer, 1930)
Pristinella notopora (Cernosvitov, 1937a)
Pristinella osborni (Walton, 1906)
Pristinella rosea (Piguet, 1906a)
Description
Small transparent worms. Prostomium without proboscis. No eyes. Dorsal bundles beginning from II, consisting of hair chaetae and needle chaetae. In mature individuals, male pores in VIII. Genital chaetae can occur. Absence of a proboscis is the only external difference from the closely related genus Pristina Ehrenberg, 1831. The genus was only recently separated from Pristina Brinkhurst, 1985. May have the rank of the subgenus, as intermediate characters occur in some species. Recently, Collado and Schmelz, 2000 have fused it with the senior genus Pristina again.
Distribution
Cosmopolitan.
Ecology
In freshwater, particularly among macrovegetation.
Reproduction
Mostly asexual, by paratomy (budding). Mature individuals and sexual reproduction rare or seasonal.
Literature
Brinkhurst, 1985: 472; Collado and Schmelz, 2000: 509-516.