Alburnoides kosswigi
Common name. Sakarya spirlin.
Diagnosis. Distinguished from other species of Alburnoides in Mediterranean, Marmara, and Black Sea basins by: ○ body depth at dorsal origin usually greater than head length / ○ horizontal eye diameter smaller than interorbital distance / ○ ventral keel completely scaleless or covered by 1−3 scales / ○ snout slightly pointed / ○ mouth terminal, upper lip slightly projecting lower lip / ○ tip of mouth cleft situated at horizontal line with middle of eye or slightly below / ○ 40−55+2−3 lateral-line scales / ○ 4 pharyngeal teeth in long row on right 5 th ceratobranchial / ○ 11−14½, usually 12−13½, branched anal rays / ○ 5−7 gill rakers. Size up to 97 mm SL.
Distribution . Türkiye: Sakarya drainage and Lake Ilgın basin.
Habitat. Fast-flowing streams and rivers with gravel and cobbled bottoms.
Biology. No data.
Conservation status. LC.
Further reading. Turan et al. 2017b (description); Bektaş et al. 2019 (phylogeny); Canoğlu et al. 2023 (barcoding).