(Levinsen, 1884)
Description
Medium-sized white, grey, yellowish or brownish worms. Chaetae sigmoid, simple-pointed, sharp, with nodulus. Ordinary chaetae by 2-12 in fan-like bundles, 65-86 µm long and 2-8 µm thick; missing at male pores. In ventral bundles, considerably more chaetae than in dorsal ones. In dorsal bundles of V-VII or V-VIII single giant chaetae, up to 12 µm thick. Male pores in XII, clitellum in XII-XIII. Internal characters: Dorsal lobes of pharyngeal glands at 4/5 and 5/6, ventral ones in V and VI. No pharyngeal, oesophageal or intestinal appendages. Coelomocytes spindle-shaped, colourless, finely granulated with a few large granules. Blood colourless, dorsal vessel reaching backward up to XVI-XX. Spermathecae in V, connected with oesophagus, consisting of short ampulla, twice as long ectal duct, and 1-2 pear-shaped diverticula; no glands on dorsolateral spermathecal pore in 4/5. Length 10-20 mm, segment number 42-55. Easily distinguished from congeners in having dorsal giant chaetae. A variety with a forward shift of reproductive organs (with male pore in X) has been recorded.
Burrowing in sediment.
Distribution
Holarctic.
Ecology
In wet soil and in freshwater near the shore.
Reproduction
Sexual, with eggs laid in cocoons.
Literature
Levinsen, 1884: 235; Michaelsen, 1888a: 494; Bretscher, 1901: 189-223; Friend, 1913b: 462; Nielsen and Christensen, 1959: 35-36, Figs 6-8; Kasprzak, 1986: 91-92, Figs 161-172.