Taxonomy & naming
The species was described by Alexander Prokofiev in 2007 as Orthrias potaninorum, based on a single specimen 4 in SL collected by the Russian explorer Grigory Nikolaevich Potanin in 1887 from Gansu Province and/or the upper Xilingol River in Inner Mongolia. The genus Orthrias has since been synonymised with Barbatula, and the Catalog of Fishes — the authority for valid names — currently lists the species as Barbatula potaninorum.
A 2012 revision by Cao and colleagues re-examined the North China Barbatula fauna and confirmed three valid species in the region: B. altayensis, B. nuda, and B. potaninorum, distinguishing B. potaninorum by its fully scaled body, pelvic fins that insert anterior to the dorsal-fin origin, and widely separated nostrils. The species belongs to Nemacheilidae, the stone and brook loaches, by far the largest family in the loach superfamily Cobitoidea and one still being actively resolved genus by genus.
Morphology
Like other members of its genus, Barbatula potaninorum is a small, elongate, laterally compressed loach with a rounded snout and a low, sucker-like mouth surrounded by three pairs of barbels used to feel out food on the streambed. The type specimen measured 4 in SL, and FishBase records a maximum length around 4 in — a modest size typical of the family. Diagnostic features noted in the 2012 revision include a body covered in small scales (unlike some scaleless nemacheilids), pelvic fins set forward of the dorsal-fin origin, and nostrils spaced well apart on the snout.
As with its relatives, the skin carries only fine, deeply embedded scales rather than heavy armour, and — as in many stream loaches — an erectile spine below the eye may be present, though this has not been specifically documented for the species. Data on colour pattern and finer anatomical detail beyond the original description and the 2012 revision are not available in the cache; the species is not well illustrated in the literature.
Habitat
Barbatula potaninorum is known from North China, with records pointing to Gansu Province and the upper Xilingol River drainage in Inner Mongolia — a limited, poorly surveyed range at the edge of the Tibetan Plateau's eastern foothills. FishBase classifies it as a freshwater, demersal, subtropical species, consistent with the broader stone-loach pattern of clear, flowing streams over gravel and stone rather than still or heavily vegetated water.
No detailed habitat account — substrate, current speed, elevation, or associated species — has been published for this specific population. Its closest well-studied relative, the European stone loach Barbatula barbatula, lives in cool, clean, well-oxygenated streams and rivers, a broad ecological template that likely applies here too, but the two species occupy entirely separate drainages on opposite ends of Eurasia and should not be assumed identical in their requirements.
Feeding
FishBase records a trophic level around 2.7, placing Barbatula potaninorum toward the herbivorous-detritivorous end of the spectrum rather than as a dedicated invertebrate hunter — it likely grazes algae, biofilm and organic detritus off stones alongside small invertebrates picked from the substrate, in keeping with the barbel-guided, bottom-sifting feeding style typical of stone loaches.
No specific dietary study of this species has been published. In the aquarium, stone loaches of this type generally do well on sinking foods — small pellets, wafers, and occasional live or frozen fare — but no husbandry record exists for this species to confirm feeding behaviour in captivity.
Mating
Nothing specific has been documented about courtship, sexual dimorphism, or spawning behaviour in Barbatula potaninorum. FishBase notes that its maturity range is unknown. The genus as a whole follows the typical nemacheilid pattern of egg-scattering with no pair bond or nest, but no direct observation of this species' reproductive behaviour has been recorded in the available sources.
Breeding
As with the great majority of stone and brook loaches, Barbatula potaninorum is not known to have been bred in the aquarium. FishBase explicitly notes it as rarely or not bred in captivity. Where breeding is documented in the genus and family generally, it follows an egg-scattering pattern over gravel in fast-flowing water with no parental care afterward — but there is no confirmed record of this happening for B. potaninorum specifically, in the wild or in a tank.
Given how narrow and lightly surveyed its known range is, and that the species is essentially absent from the aquarium trade, the honest statement is that its breeding biology remains undescribed.
In the aquarium
Barbatula potaninorum is not established in the aquarium hobby and no husbandry record for the species could be found. It is a small fish — around 4 in at most — so if it were ever kept, a modest cool-to-cold-water setup with a sand or fine-gravel substrate, water movement, and strong oxygenation would suit its stream-loach biology, following the general pattern of its better-known congener Barbatula barbatula (tolerant of temperatures from near-freezing up to the low twenties Celsius). As with all thin-scaled loaches, care with medication dosing would be prudent given the family's general sensitivity, though this has not been specifically tested in this species.
Because no trade history or aquarium account exists, prospective keepers should treat any offered specimen as effectively an unknown quantity and research the specific origin and conditions of any wild-caught stock before attempting to keep it.
Conservation
Barbatula potaninorum is assessed as Data Deficient, with a FishBase-cited IUCN assessment dated 14 November 2024. This reflects how little is known about the species: it is recorded from a narrow, sparsely surveyed range in North China and possibly Inner Mongolia, and no population trend, abundance estimate, or specific threat assessment has been published.
There is no evidence of the species entering the aquarium trade, so collection pressure is not a documented concern; any risks to this fish would most plausibly come from broader stream habitat change across its limited known range, but this has not been formally studied.