Gymnocephalus ambriaelacus
Gymnocephalus ambriaelacus is a species of freshwater ray-finned fish, a ruffe, from the family Percidae which is endemic to Lake Ammersee, in the upper Danube basin in southern Germany. This species can reach a length is (SL). The species is classified as Critically Endangered as its population is declining following the introduction of the ruffe ("Gymnocephalus cernua"). Some authorities suggest that this taxon may be synonymous with the Balon's ruffe ("G. baloni").