Hrabe, 1939
Description
Medium-sized pink worms. Prostomium bluntly conical. External secondary annulation present. preserved specimens often bent at dorsal side. Chaetae two per bundle, sigmoid with distal nodulus, sharply single-pointed, 82-100 µm long and 5 µm thick. Unpaired spermathecal pore in VIII or lacking; unpaired male pore in X. Clitellum in (VIII) IX-XIV (XV). Pharyngeal glands extend from IV-VIII. Chloragogen tissue on digestive tube begins from IX. Testes in IX and X, ovaries in XI. Single atrium in X consisting of oblong ampulla and indistinctly separated efferent duct; irregular masses of high prostatic tissue attached to the junction of atrial ampulla and efferent duct only, or lacking. Small conical penis present. Single median spermatheca in VIII with sacculate ampulla and long discrete duct; many individuals lack any spermatheca. Length 8-28 mm, segment number 50-85. Differing from the other European lumbriculid with unpaired ventral genital pores, Eclipidrilus lacustris, in smaller size, position of the spermathecal pore, if present, in VIII (instead of IX), sacculate atrial ampulla with scarcer prostatic cover, and a less complicated blood vessel system.
Burrowing in sediment. Not swimming.
Distribution
Northern Europe, Kamchatka.
Ecology
In freshwater, rare.
Reproduction
Sexual only, apparently mostly parthenogenetic. Eggs laid in cocoons.
Literature
Hrabe, 1939: 229-235, Figs 9-14; Hrabe, 1981: 105, Pl. 18, Fig. 14; Cook, 1971a: 262, Fig. 5.10A-D; Kasprzak, 1981: 189, Figs 749-752.