Geiger & Schliewen, 2010
Gymnocephalus ambriaelacus, a new species of ruffe from Lake Ammersee, southern Germany (Teleostei, Perciformes, Percidae).A new ruffe of the genus Gymnocephalus (Teleostei, Perciformes, Percidae) is described from Lake Ammersee (Bavaria, Germany). G. ambriaelacus, new species, belongs to the subgenus Acerina and is distinguished from G. (Acerina) cernua (Linnaeus, 1758) by a smaller angle between the posterior dorsal fin margin and the caudal peduncle (90-110° vs. 113-154°), by a larger eye diameter (10.2-12.3 % SL vs. 7.9-10.5 % SL) and by an irregular pattern of large dorsolateral dark blotches vs. a pattern of small dots. It is distinguished from G. (Acerina) baloni Holcík & Hensel, 1974 by the combination of a larger eye diameter (10.2-12.3 % SL vs. 8.2-10.5 % SL), a smaller caudal peduncle depth (7.7-8.9 % SL vs. 7.4-10.1 % SL), and a higher mean and modal number of pectoral fin rays (15 vs. 13). Further, it is distinguished from all Gymnocephalus species by a unique nuclear LdhA6 intron haplotype. According to phylogenetic analysis of both nuclear and mitochondrial sequence data the new species is the sistertaxon to G. baloni. With Salvelinus evasus Freyhof & Kottelat, 2005 and Coregonus bavaricus Hofer, 1909, this is the third endemic species from Lake Ammersee.
Matthias F. Geiger & Ulrich K. Schliewen
Spixiana, 33 (1): 119–137, 2010.