The fauna of Oligochaeta (Annelidae) of the Upper Vychegda River (Komi Republic, Russia)

Study Extent

The dataset provides information on the number of individuals of aquatic oligochaete in zoobenthos sample.

Sampling

The upper course of the Vychegda River (a tributary of the Northern Dvina) was studied. In the mountainous part, the river is 10-35 m wide, and the substrate is predominantly gravel and boulders. Numerous rapids are noted along the river. The riverbed consists of boulders and pebbles. Sandy substrates are often found in the pools, and the pool bottoms are silted. In the plain part, the channel widens to 50-100 m, with the riverbed predominantly composed of gravel or sand.

Quality Control

The data were collected and identified by specialists from the Institute of Biology of the Komi Scientific Center of the Ural Branch of the Russian Academy of Sciences. Morphological analysis specimens were performed using compound microscopes BIMAM R13-1, Leica DM 4000B. For identification of species we used both standard keys and data reported in modern studies specifically addressing the taxonomy (Chekanovskaya 1962; Timm 2009; Key to identification of zooplankton and zoobenthos, 2010, Schmelz, Collado, 2010). 1. Key to Identification of Zooplankton and Zoobenthos of Fresh Water of European Russia, KMK Scientific Press, Moscow, 2010, pp. 151–183. [In Russian]. 2. Schmelz R., Collado R. A guide to European terrestrial and freshwater species of Enchytraeidae (Oligochaeta). Soil organisms. Vol. 82. pp. 1-176. 3. Chekanovskaja O.V. Aquatic oligochaetes of the fauna of the USSR. Moscow-Leningrad: Nauka. 1962. 412 pp. [in Russian]. 4. Timm T. A guide to the freshwater Oligochaeta and Polychaeta of northern and central Europe. Lauterbornia, 1999. Issues 66. 235 pp.

Method steps

1. Oligochetae samples were taken with a Petersen grab (sampling area 0.025 m2) on soft bottoms and with a hydrobiological scraper (blade length 20 cm and mesh size of the attached with mesh size ≤158 μm, sampling area 0.04 m2) on gravel bottoms. Samples were preserved in 4% formaldehyde (in the field) and examined under light microscopes in the laboratory. Morphological analysis was performed using a stereomicroscope Leica DM 4000. The worm species affiliation was ascertained under existing taxonomic keys in accordance with the present-day classification of each group. Voucher specimens were deposited at the Institute of Biology, Syktyvkar (Oligochaeta).

This dataset provides current data on oligochaete fauna of the upper reaches of the Pechora and Vychegda rivers.

1. Oligochaeta
   rank: subclass
2. Tubificida
   rank: order
3. Naididae
   rank: family
4. Naidinae
   rank: subfamily
5. Tubificinae
   rank: subfamily
6. Enchytraeidae
   rank: family
7. Lumbriculidae
   rank: family
8. Lumbricidae
   rank: family
9. Propappidae
   rank: family

The research area includes only the upper reaches of the Vychegda rivers. The upper course of the Vychegda River is the section from the source to the confluence with the Nem River. It belongs to the Timan Middle Taiga Province and originates on the Pechora-Vychegodsky Plateau. The length of the upper section of the Vychegda River is 32.2%. The river's catchment area is located in the Southern Timan region and the adjacent plains. The entire upper course is divided into mountainous and plain parts