Gymnocephalus acerina (Gmelin, 1789)
Donets ruffe
photo by Geraskin, A.

Family:  Percidae (Perches), subfamily: Percinae
Max. size:  21 cm SL (male/unsexed)
Environment:  demersal; freshwater
Distribution:  Europe: basins of northern Black Sea and Sea of Azov in Dniester, South Bug, Dniepr, Don rivers and Kuban drainages; in Dniepr up to Belarus. Rare in most of its range.
Diagnosis:  Dorsal spines (total): 17-19. Distinguished uniquely from its congeners by having roundish dark spots on body, mostly in 3 rows, first below dorsal base, and 50-55 + 4-5 scales along lateral line. Can be further separated from other species of the genus by having 17-19 dorsal spines (Ref. 59043).
Biology:  Found in flowing waters and lakes with clear water. Also inhabits rapids during summer. Occurs over sand and gravel bottom but prefers hard compact sand. Usually crepuscular but feeds also during daytime. Preys predominantly on benthic invertebrates (crustaceans, insect larvae, molluscs), rarely on fish. Forms small schools. In September, starts forming large schools and moves to deeper places and remains inactive until ice melts. Does not undertake long distance migrations. Spawns in small schools river stretches with heavy current and sand or gravel bottom (Ref.59043).
IUCN Red List Status: Least Concern (LC); Date assessed: 01 January 2008 Ref. (130435)
Threat to humans:  harmless


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