Clitellate communities in anomalous region of Lake Baikal, Eastern Siberia (Russia)

In this paper, we described the clitellate fauna from an underwater hydrothermal vent zone in Frolikha Bay (Northern Baikal), where a unique community of oligochaetes dominate the zoobenthic communities. In total, twenty one oligochaete species were collected and of these, 19 species belong to the Naididae (former Tubificidae). In addition, one species belonging to the Propappidae, Propappus glandulosus, and another, widespread in the lake, to the Lumbriculidae, Lumbriculus achaetus, were identified. High indices of oligochaete development were revealed in the study which are uncharacteristic for the abyssal zone of Lake Baikal. The hypothesis of possible dependence of species composition and quantitative characteristics of oligochaetes on the development of bacteria Thioploca in the area was not confirmed.