(Hartmann, 1821)
Description
Very long, thread-like pink or red worms. Prostomium extended, with external transversal groove (0/1). Secondary annulation present in forebody. Chaetae usually one (rarely two) per bundle, slightly sigmoid, thick, simple-pointed. Dorsal chaetae smaller than ventral ones, or can even be lacking in some segments. Hence either four or two chaetae per segment. Pharynx massive, muscular. Clitellum, if present, in X-XIII (or in XI-XXVIII?); paired male pores in XI and XII, spermathecal pores lateral in VII-IX. Length up to 300 mm, diameter 0.2-2 mm, segment number 200-480. Described under many different names mostly serving as synonyms. Some of the described (exotic, hence not listed here) variations can be independent species.
Burrowing in sediment.
Distribution
Holarctic, south of the former continental glaciation area.
Ecology
In freshwater. In various cooler surface waters and in subterranean waters; also in wet soil. Possibly predatory.
Reproduction
Sexual only. Eggs laid in cocoons.
Literature
Hartmann, 1821: 45; Hoffmeister, 1843: 193, Pl.IX Fig. 7; Claparède, 1862: 275, Pl. III Fig. 16; Vejdovsky, 1884b: 49-50, Pl. XII Figs 3-9; Brinkhurst and Jamieson, 1971: 289-291, Fig. 6.2A-C; Chekanovskaya, 1981: 403-404, Fig. 203; Hrabe, 1981: 116-117; Kasprzak, 1981: 210-211, Figs 841-844.