Gymnocephalus cernua ( Linnaeus, 1758 )

Artaev, Oleg & Ruchin, Alexander B., 2017, The ichthyofauna of the Moksha River, a tributary of the Volga river basin, Russia, Check List 13 (4), pp. 185-202 : 198-200

Gymnocephalus cernua ( Linnaeus, 1758) , Ruffe.

Perca cernua Linnaeus 1758: 294 .

Gymnocephalus cernua — Kottelat and Freyhof 2007: 528. Gymnocephalus cernuus — Reshetnikov et al. 2003b: 62.

Material examined. Table 1.

Presence of two confluent dorsal fins, and body depth

24–27% SL. This species inhabits different size rivers, oxbows, and storage reservoirs, most frequently in rivers 101–300 km from the source (47.7%) and storage reservoirs (66.7%). In the latter, this species was most abundant in catches (19.1%).

Perca fluviatilis Linnaeus, 1758 , European Perch. Perca fluviatilis Linnaeus 1758: 289 — Kottelat and Freyhof 2007: 530

Material examined. Table 1

Presence of dark blotch on posterior portion of dorsal fin, and five to eight bold dark bars on flank. It is a wide-

spread species, which was recorded in all types of water bodies. In rivers, this species is most frequent 100 km from the source and in other water bodies, in streaming oxbow lakes. Its share in river catches is low and varies from 2.8 to 9.7%, being approximately the same for the flow-through lakes. Such as for the remaining water bodies, its share in catches is higher, amounting to 12.8– 31.4%, with a maximum in ponds.