Taxonomy & naming
Oxynoemacheilus veyselorum was formally described in 2018 by Cüneyt Çiçek, Soheil Eagderi and Esra Sungur in the Iranian Journal of Ichthyology, from material taken in the upper Aras (Araxes) River drainage in Kars Province, north-eastern Turkey. It sits in the genus Oxynoemacheilus, one of the many segregate genera carved in recent decades out of the old, over-broad "Nemacheilus" / "Noemacheilus" grouping that once swallowed most Eurasian stone loaches; Oxynoemacheilus today holds a large number of species across Anatolia, the Levant, the Caucasus and Iran.
The species belongs to the family Nemacheilidae, the stone or brook loaches, within the loach superfamily Cobitoidea. The Catalog of Fishes governs the valid combination, and as a recently described, narrowly known species it has not been subject to any further taxonomic revision since its 2018 description; the genus placement used here follows that original paper and current authority.
Morphology
The original description characterises Oxynoemacheilus veyselorum by a row of mid-lateral dark brown blotches along the flanks, a comparatively small eye (roughly 9.6–13.7% of head length), a short dorsal-fin base (about 10.1–13.3% of standard length), a notably deep body (around 17.3–19.4% of standard length) and a slightly emarginate caudal fin. Mature males show a suborbital groove and rows of small keratinised tubercles (unculi) on the pectoral and dorsal-fin rays, a feature typical of breeding-condition male nemacheilids.
As in other stone and brook loaches, the skin is effectively naked to the eye — scales are tiny and deeply embedded rather than absent altogether — which matters for how the fish should be handled and, in the aquarium, how it should be medicated. Detailed comparative morphometrics beyond the type description are not available in the sources consulted here.
Habitat
The type locality lies in the upper Aras River drainage of Kars Province, Turkey, and the species has also been recorded more broadly through the Aras system and reported from river basins in Iran that drain toward the Caspian Sea. Like other members of its family it is a fish of clear, flowing, well-oxygenated streams over gravel and stone substrates — the classic stony riffle-and-run habitat that gives Nemacheilidae its common name.
The Aras basin sits at real elevation in the Anatolian and Caucasian highlands, so this is a cool-water stream fish rather than a warm lowland species; nothing in the available sources suggests it tolerates the warm, still, blackwater conditions favoured by many tropical loaches. Precise present-day water-quality data (temperature range, pH, flow regime) has not been published beyond the original taxonomic description, and should be treated as inferred from the family and region rather than measured for this species specifically.
Feeding
No dedicated dietary study of Oxynoemacheilus veyselorum has been published. Based on the well-documented ecology of Nemacheilidae as a whole, it is reasonable to expect it forages as a benthic micro-predator, picking small aquatic invertebrates, insect larvae and crustaceans from among the gravel and stones of its home streams, likely with some nocturnal activity as in related species.
In the absence of species-specific feeding data, any aquarium diet should follow that general nemacheilid pattern — small sinking live, frozen and prepared foods rather than flake — but this is an inference from the family, not a confirmed observation of this species.
Mating
The original description notes that mature males carry a suborbital groove and unculi (small tubercles) on the pectoral and dorsal-fin rays, features typically associated with breeding condition in male nemacheilids and likely used in courtship or spawning contact. Beyond this anatomical detail, no account of courtship behaviour, seasonal timing or spawning triggers has been published for the species.
As with the great majority of stone and brook loaches, Oxynoemacheilus veyselorum has never been reported spawning in captivity, so there is no aquarium observation to draw on; what little is known comes solely from preserved specimens examined for the type description.
Breeding
There is no published or hobby record of Oxynoemacheilus veyselorum being bred, or even kept, in the aquarium. Going by the general pattern for Nemacheilidae, stone and brook loaches are egg-scatterers that release eggs over gravel and among stones in fast-flowing water with no parental care afterward — but this is the family pattern, not a confirmed observation for this species.
Given how narrowly it is known — essentially from its type series and a handful of subsequent locality records — data on its reproductive biology is genuinely sparse, and it should be treated as an unknown-in-the-hobby species rather than one with an established captive-breeding history.
In the aquarium
Oxynoemacheilus veyselorum does not appear to be established, or even present, in the aquarium trade; the sources consulted here are entirely taxonomic and regional-checklist literature, with no hobbyist care reports. Any aquarium guidance therefore has to be extrapolated cautiously from its genus and family rather than drawn from direct experience with the species.
Were it to be kept, a small Oxynoemacheilus from a cool Anatolian/Caucasian stream system would be expected to need cool-to-moderate, clean, well-oxygenated, flowing water over a gravel or stone substrate — not a warm, still tropical setup — plus the general nemacheilid cautions that apply across the family: near-scaleless skin that is sensitive to copper and full-strength medications, and a preference for sinking foods over flake. This should be read as informed inference, not a documented care profile.
Conservation
Oxynoemacheilus veyselorum has not been evaluated by the IUCN Red List, so it carries no formal conservation category; it is recorded here as Not Evaluated rather than assigned a guessed status. As a narrow-range stream endemic known mainly from the upper Aras River drainage, with further records from Iranian Caspian-basin systems, it shares the vulnerability profile common to many recently described Nemacheilidae — small known range, limited survey effort, and exposure to the general pressures on Anatolian and Caucasian river systems such as water abstraction, damming and pollution.
There is no evidence in the available sources of any aquarium-trade collection pressure on this species; its conservation picture, such as it is, rests entirely on habitat considerations rather than trade data.