(Hrabe, 1941)
Description
Medium-sized smooth pink worms. Prostomium short conical, separated by a distinct furrow from I, in alcohol-preserved specimens. Body wall delicate, with deep intersegmental furrows on tail when preserved. Anterior dorsal bundles with 2-5 comparatively short (120-190 µm), bent hair chaetae and 4-6 crotchets, 74-122 µm long, with slightly shorter and thinner upper tooth, without any intermediate teeth. Anterior ventral chaetae 3-10 per bundle, 70-110. µm long, with slightly longer and thinner upper tooth. Spermathecal chaetae 105-200 µm long. Male pores in XI, accompanied with a few ordinary crotchets. Similar to Potamothrix hammoniensis in every respect but for the shape of dorsal chaetae both of hairs and crotchets.
Burrowing in sediment.
Distribution
Europe, Caspian Sea, eastern North America. In NWE probably as a recent immigrant from the Ponto-Caspian basin.
Ecology
In fresh and slightly brackish water.
Reproduction
Sexual only. Eggs laid in oval or roundish cocoons with transparent shell and unequal appendages..
Literature
Hrabe, 1941: 22-25, Figs 20-25; Hrabe, 1981: 79; Brinkhurst and Jamieson, 1971: 494, Fig. 8.12C-E; Chekanovskaya, 1981: 324-325, Fig. 158; Kasprzak, 1981: 157, Figs 527-532.