(Piguet, 1906a)
Description
Transparent worms. Prostomium with eyes. Dorsal bundles beginning from VI, consisting of 2-6 bifid chaetae similar to ventral crotchets, 78-88 µm long, with upper tooth slightly longer, and 0-3 very fine, only 84-120 µm long hair chaetae. Ventral chaetae of the same shape, by 3-9, slightly longer (84-96 µm) than dorsal ones. Mature individuals without any penial chaetae but sabre-shaped spermathecal chaetae present in V, two per bundle, simple-pointed or with reduced lower tooth. Length 3-7 mm, segment number in zooids 17-24, in single individuals 24-42. Can be confused with Uncinais uncinata if small hair chaetae remain unnoticed.
Crawling on substratum.
Distribution
Western Palaearctic, recorded also from the northeastern USA.
Ecology
In freshwater, mostly on sand.
Reproduction
Mostly asexual, by paratomy (budding). Mature individuals and sexual reproduction rare or seasonal.
Literature
Piguet, 1906a: 231-234, Pl. X Fig. 1, Pl. XI Figs 1-3, Pl. XII Fig. 7; Sperber, 1939: 1-3, 5, Fig. 1; Sperber, 1948: 151-153, Figs 17, 27E, Pl. XII-XIII, Pl. XIV Fig. 1; Sperber, 1950: 69, Fig. 20; Brinkhurst and Jamieson, 1971: 355, Fig. 7.11D-H; Chekanovskaya, 1981: 240, Fig. 108; Hrabe, 1981: 54-55, Pl. 8 Figs 22-23; Kasprzak, 1981: 130-131, Figs 385-390.