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Gymnocephalus cernuus Linnaeus als Acerina cernua Linnaeus Fig Matschie et al. .svg en Drawing of the Eurasian Ruffe Gymnocephalus cernuus Linnaeus described as Acerina cernua Linnaeus Fig de Zeichnung des Kaulbarschs Gymnocephalus cernuus Linnaeus als Acerina cernua Linnaeus beschrieben Fig Matschie Reichenow Tornier Pappenheim