(D'Udekem, 1855)
Description
Small worms, body surface covered with fine detritus adhering to glandular epidermal papillae, brown. Rows of colourless, prominent sensory papillae also present on each segment but usually hidden in detritus coat. Eyes present. Dorsal bundles beginning from VI, consisting of 1-2 hair chaetae and 1-2 needle chaetae. Hair chaetae of VI up to 800 µm long, usually considerably longer than those of the subsequent segments (270-450 µm). Needle chaetae 60-70 µm long, their tip forming a small knob. Ventral chaetae by 2-5, with slightly longer and thinner upper tooth, in II 111-147 µm long, in the subsequent segments 98-138 µm. In mature individuals penial chaetae by 3, with sharp curved tip. Length 2-20 mm, segment number in zooids 19-29, in single individuals 23-46. The only European naidid with detritus coat. Can be confused, at first sight, with some armoured tubificid species but differing from them in beginning of dorsal bundles from VI, and in presence of extremely long hair chaetae in the same segment.
Crawling on substratum, sluggish.
Distribution
Cosmopolitan.
Ecology
In freshwater, particularly in marshy vegetation-rich habitats.
Reproduction
Mostly asexual, by paratomy (budding). Mature individuals and sexual reproduction rare or seasonal.
Literature
D'Udekem, 1855: 552, Fig. 3; Timm, 1883: 153, Pl. XI Fig. 25; Sperber, 1948: 133-136, Figs 15A-B, 26B; Sperber, 1950: 65, 17A-B; Brinkhurst and Jamieson, 1971: 344-345, Figs 7.8R, 7.9A-C; Chekanovskaya, 1981: 208-210, Fig. 88; Hrabe, 1981: 49-50, Pl. 7 Figs 15-18; Kasprzak, 1981: 115, Figs 301-303.