Nielsen and Christensen, 1961
Description
Small transparent worms. Chaetae mostly by 2, but dorsal bundles lacking in IX-XI and containing only one chaeta in VII-VIII. No ventral chaetae at male pores in XII. Clitellum extends over XII-1/2 XIII, almost square gland cells arranged in transverse rows with clear interspaces. Internal characters: All three pairs of pharyngeal glands in 4/5-6/7 with dorsal connections; ventral lobes present in V and VI. Coelomocytes oval, finely granulated. A pair of hollow, club-shaped dorsolateral appendages attached to oesophagus in IV. Blood colourless, dorsal vessel reaching backward to XIII. Spermathecae with small pear-shaped ampulla, and long ectal duct covered irregularly with very small glandular cells; no glands at distal end. Ental ends of ampullae join above oesophagus before communicating with the latter. Male funnels small and thin, six times as long as width, collar of similar width but high; both funnel and collar seem to be unilaterally reduced. Penial bulb small and compact. Differing from similar small congeners with paired chaetae, with respect to the location of segments with reduced dorsal bundles. Can be confused also with small species of the terrestrial genus Enchytronia (not treated in this guide), but they lack dorsal bundles in VIII-XI and reveal intestinal diverticula in VI. Length about 6 mm, segment number 27-29.
Burrowing in sediment.
Distribution
Europe, California.
Ecology
In soil, also in freshwater wetlands.
Reproduction
Sexual, with eggs laid in cocoons.
Literature
Nielsen and Christensen, 1961: 21-22, Figs 19-20; Kasprzak, 1986: 161-162, Figs 540-541.