Gymnocephalus

Gymnocephalus
Eurasian ruffe, (G. cernua)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Percidae
Subfamily:	Percinae
Genus:	Gymnocephalus Bloch, 1793
Type species
Perca schraetser Linnaeus, 1758
Synonyms
Cernua J. C. Schaeffer, 1761 (not available) Schraitser J. C. Schaeffer, 1761 (not available) Acerina Güldenstädt, 1775 (either unavailable or needs to be suppressed) Cephimnus Rafinesque, 1815 Acerina G. Cuvier, 1816 Cernua J. Fleming, 1828 Gremilla Gistel, 1848 Leptoperca T. N. Gill, 1861 Cephimnus Rafinesque, 1815

Gymnocephalus is a genus of perches native to Western Eurasia. They are collectively called ruffes and resemble the common perches (Perca), but are usually smaller and have a different pattern.

There are currently five recognized species in this genus:

In Europe they are found in the Caspian, Black, Baltic and North Sea basins; in Asia in the Aral Sea basin and the Arctic Ocean basin eastward to Kolyma drainage.

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