(Michaelsen, 1903a)
Description
Big smooth pink, red or bluish worms. Chaetae bifid with shorter upper tooth; anterior chaetae 3-8 per bundle, 90-170 µm long, sometimes with worn rounded teeth, or with blunt tip without any teeth. No ventral chaetae in XI near male pores in mature worms. Anterior dissepiments thickened, funnel-shaped in preserved specimens. Length 45-90 mm, diameter 1-3 mm, segment number up to 156. Tubifex newaensis is the largest tubificid species in NWE, easily distinguishable by its size even when young. The short upper tooth in all chaetae, anterior and posterior, is a rare character but shared with Aulodrilus limnobius and some other, also very small tubificids with penial chaetae. Tubifex newaensis is rather different from the other species of Tubifex in the external appearance but similar to them in the anatomy of reproductive system.
Burrowing in sediment, including hard sandy bottom.
Distribution
Western Palaearctic (originally the Ponto-Caspian basin), Great Lakes of North America; only invading NWE.
Ecology
In freshwater, particularly on sandy bottom of large rivers.
Reproduction
Sexual only. Eggs laid in large oval cocoons with transparent brownish shell and two long appendages.
Literature
Michaelsen, 1903a: 3-6, Figs 1-2; Brinkhurst, 1962: 307-312, Figs 1-3; Brinkhurst and Jamieson, 1971: 457, Fig. 8.1H-J; Chekanovskaya, 1981: 314-315, Fig. 151; Kasprzak, 1981: 178, Figs 702-708.