Oxynoemacheilus fatsaensis

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 504-505

Oxynoemacheilus fatsaensis

Common name. Yeşilırmak sportive loach.

Diagnosis. Distinguished from other species of Oxynoemacheilus in Black Sea basin by: ○ caudal–peduncle depth 7–9 % SL, usually 2.0–2.6 times in its length, without high adipose crest or ridge / ○ caudal emarginate, middle caudal ray 80–90 % of length of longest ray in upper caudal lobe / ○ lateral line complete / ○ flank covered by scales / ○ suborbital groove present in male / ○ one central or no black, grey or brown blotch or short bar on caudal base, its colour identical to blotches on caudal peduncle / ○ no yellowish triangles at posteriormost portion of caudal peduncle / ○ pelvic very long, reaching or almost reaching to anus / ○ pectoral in male very long, reaching or almost reaching to pelvic origin / ○ flank mottled or with large irregularly shaped, squarish or vertically elongate blotches, usually as wide or narrower than interspaces / ○ lateral blotches on caudal peduncle usually interrupted in size and/or shape at or above lateral midline. Size up to 75 mm SL.

Distribution . Türkiye: Yeşilırmak drainage and adjacent coastal stream Elekçi.

Habitat. Fast-flowing water in streams and rivers with gravel substrate.

Biology. No data.

Conservation status. LC.

Remarks. No external characters are known to distinguish this species from O. bergianus , O. banarescui , and O. simavicus , and all species are diagnosed only by molecular characters. Published differences are based on small sample sizes or are spurious. As these four species are allopatric, the distribution areas should help in identification.

Further reading. Saygun et al. 2021 (description); Freyhof et al. 2022 (revision of O. bergianus group).

Figures

Oxynoemacheilus fatsaensis

Distribution