Oxynoemacheilus hazarensis, Freyhof & Ozulug, 2017

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 511-512

Oxynoemacheilus hazarensis

Common name. Hazar loach.

Diagnosis. Distinguished from other species of Oxynoemachei - lus in Tigris drainage by: ● flank naked, only caudal peduncle behind anus with scales / ○ suborbital groove present in male / ○ lateral line incomplete / ○ caudal slightly emarginate / ○ a deep incision in middle of upper lip / ○ mottled or marmorated colour pattern on flank, not interrupted by an unpigmented zone along lateral line. Size up to 67 mm SL.

Distribution. Türkiye: Lake Hazar basin.

Habitat. Lakeshores and moderately fast-flowing, stagnant waters of streams, backwaters, and springs with muddy bottoms.

Biology. No data.

Conservation status. EN; appears to be declining within its very small range.

Remarks. This species is not closely related to other species in the Tigris but belongs to a group of loaches that are mostly found in the Euphrates.

Conservation status. VU; appears to be declining within its small range.

Remarks. The Iranian population is superficially very similar, but their COI sequence data place them close to O. marunensis . They may represent O. hanae , introgressed by O. marunensis . In the upper Sirvan, O. hanae and O. marunensis occur in syntopy.

Further reading. Freyhof & Abdullah 2017 (description); Jouladeh-Roudbar et al. 2020 (record from Iran).

Further reading. Freyhof & Özuluğ 2017 (description); Freyhof et al. 2019b (diagnosis).

The Dead Sea basin and the Jordan. The present-day Jordan-Dead Sea basin results from tectonic activities that commenced during the Miocene/Pliocene transition. The Yizre’el Valley was formed during this period, and the Jordan Valley was lowered. During the Pliocene, the Jordan flowed from south to north and drained along with the Litani via Nahal Qishon toward the Mediterranean. During the Lower Pleistocene, the lowering of the Jordan-Wadi Araba graben continued, forming two endorheic basins: one in the Hula and the other in the Dead Sea region. At that time, the Jordan was no longer connected to the Litani but rather flowed southeastward into the Jordan Valley.

Oxynoemacheilus insignis ; Barada drainage, Syria; ~ 60 mm SL.