Bretscher, 1899
Description
Small smooth pink worms. All chaetae as bifid crotchets only, 5-10 per bundle, 40-60 µm long, with much shorter and thinner upper tooth. Lateral, wing-like dilatations of distal portion of crotchets can occur in some individuals. Mature individuals rare, with male pores and beginning of clitellum in VII. Unsegmented tail portion acting as respiratory organ. Length 10-15 mm, segment number up to 80. Differing from congeners in lack of hair chaetae. Aulodrilus limnobius is one of the few tubificid species in freshwater of NWE, revealing exclusively bifid crotchets with shorter upper tooth, in all bundles. Similar chaetae occur also in Rhyacodrilus balmensis, and in the rare freshwater representatives of the marine subfamily Phallodrilinae: Gianius aquaedulcis, Gianius riparius and Spiridion phreaticola. However, these species have penial chaetae in XI while Aulodrilus limnobius has none. Unsegmented tail, characteristic of the whole genus Aulodrilus, is also typical of Aulodrilus limnobius. Tubifex newaensis, with similar chaetae, is much bigger, reproduces only in sexual way and has male pores and clitellum in XI.
Burrowing in sediment.
Distribution
Almost cosmopolitan.
Ecology
In freshwater.
Reproduction
Asexual reproduction by architomy (fragmentation) prevailing. Maturing and sexual reproduction rare. Eggs laid in cocoons.
Literature
Bretscher, 1899: 379-388; Brinkhurst and Jamieson, 1971: 524-525, Fig. 8.23G-H; Chekanovskaya, 1981: 281-282, Fig. 134; Hrabe, 1981: 72; Kasprzak, 1981: 179-180, Fig. 709.