Oxynoemacheilus banarescui (Delmastro, 1982)

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 489-490

Oxynoemacheilus banarescui

Common name. Paphlagonian sportive loach.

Diagnosis. Distinguished from other species of Oxynoemacheilus in the Black Sea basin by: ○ caudal–peduncle depth 7–10 % SL, usually 2.0–3.0 times in its length, very rarely 1.6–3.0, 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 78 mm SL.

Distribution. Türkiye: Filyos and Devrekani drainages in Black Sea basin.

Habitat. Fast-flowing streams and rivers with gravel or rock substrate.

Biology. No data.

Conservation status. LC.

Remarks. No external characters are known to distinguish this species from O. bergianus , O. fatsaensis , and O. simavicus , all of which are diagnosed by molecular characters. As these four species are allopatric, the distribution area should help in identification.

Further reading. Delmastro 1982 (description); Yoğurtçuoğlu et al. 2020a (distribution); Freyhof 2022 (revision of O. bergianus group).

Oxynoemacheilus bergi and other names of Caspian loaches. It is challenging to ascertain the number of valid species and their correct names. This often necessitates travel to type localities in remote areas. One such case is explained here. Nemacheilus bergi was described from the Kura drainage in Azerbaijan and was treated as a valid species without examining fish from the type locality or any other justification. In the same study, N. alasanicus from the upper Alazani in the Georgian Kura drainage was treated as a synonym of N. bergi , again without examining any materials or arguments. Early authors clearly distinguished N. bergi from Oxynoemacheilus brandtii . The account of O. bergi does not correspond to O. cyri , another species known from the Kura. Oxynoemacheilus bergi could be a third species of Oxynoemacheilus in the Kura, which has yet to be found (again). The account on O. bergi does not correspond to O. veyselorum , which has only been found in the adjacent Aras. However, it cannot be ruled out that O. bergi might be conspecific with the species identified as O. bergianus , also found in the Aras drainage. Nevertheless, there are no records of O. bergianus from the Kura, and fieldwork in late 2024 aimed to resolve the issue but failed to find it. If O. bergianus were conspecific with O. bergi , it would become a junior synonym of O. bergi . It was also suggested that two other loaches occur in the Alazani, a tributary of the Kura: N. angorae alasanicus and N. brandtii gibbusnazus . Indeed, only O. brandtii , very common in the Kura, has been recently found in the Alazani. Nemacheilus angorae alasanicus might be conspecific with O. bergianus , and both could be conspecific with O. bergi . These species should be re-examined based on materials from their type localities, and considerable efforts should be made to find the mysterious Oxynoemacheilus bergi and O. alasanicus . This is a complex issue, demonstrating that even with the publishing of this book, many questions need to be resolved. Further reading. Berg 1898, Gratzianov 1907 ( O. bergi ); Elanidze 1983 (Alazani loaches).

Oxynoemacheilus bergi ; Kura drainage, Azerbaijan; 50 mm SL. © S. Eagderi.