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

Oxynoemacheilus frenatus ; Tigris at Diyarbakır, Türkiye; ~ 70 mm SL.