Loaches · Stone & brook loaches

Oxynoemacheilus kentritensis

Freyhof, Kaya & Turan, 2017

IUCNNOT EVALUATED
NEnot on the EX–LC scale
CARESNOT LISTED
Scientific size3 in7.9 cm standard length
Depthnot recorded
DietNot specifically documented; presumed micro-predator of small benthic invertebrates in flowing water, in line with other Oxynoemacheilus, but FishBase notes limited data on diet for this species
BreedingEgg-scatterer over gravel/among stones in fast water, presumed from the genus pattern; no parental care; rarely or never documented in captivity, and no evidence this species is kept or bred in the aquarium hobby at all
Sexual dimorphismMinimalNo sexual dimorphism data published for this species
PhotographsSee photosGoogle Images →

Oxynoemacheilus kentritensis is a small stone loach described in 2017 from a single river system in the upper Tigris drainage of Turkey. Like most of its genus it is a slim, bottom-hugging micro-predator of cool, fast, clear streams, distinguished from its close relatives by fine anatomical details — a complete lateral line, long barbels and a distinctive pattern of dark blotches along the flank. It has no formal IUCN assessment and almost nothing has been published on its life history, diet in detail, or reproduction beyond the original taxonomic description, making honesty about the gaps more valuable here than speculation.

What's in the name

Oxynoemacheilus kentritensisox-ee-noh-mah-KY-lus ken-tri-TEN-sis

Oxynoemacheilus
  • oxysGreeksharp, pointed
  • noeGreekcombining element from the older genus name Noemacheilus
  • cheilosGreeklip — together referencing the genus's slender form and lip structure, building on the older nemacheilid genus name
kentritensis
  • Kentritesplace namea Latinized locality reference tied to the type locality in the upper Tigris (Botan River) drainage of southeastern Turkey, in the manner customary for Oxynoemacheilus species named after their home river system

Taxonomy & naming

Oxynoemacheilus kentritensis was formally described by Jörg Freyhof, Cüneyt Kaya and Davut Turan in 2017, in Zootaxa 4258(6):551-560. The description places it firmly in the genus Oxynoemacheilus, part of the family Nemacheilidae — the stone or brook loaches, the largest and most species-rich family in the loach superfamily Cobitoidea. The species epithet references the Botan River (the type locality lies in the upper Tigris drainage in southeastern Turkey), and the description includes explicit comparative remarks against Oxynoemacheilus frenatus, a related species from the same general region.

Oxynoemacheilus is one of several genera carved in recent decades out of the old, catch-all Nemacheilus/Noemacheilus complex as regional revisions split that group along anatomical and genetic lines; Anatolian and Middle Eastern stone loaches in particular have seen heavy taxonomic churn. The Catalog of Fishes is the governing authority for the current combination, and as of the most recent review Oxynoemacheilus kentritensis stands as a valid, distinct species with no synonymy to correct.

Morphology

This is a small, elongated loach reaching only about 3 in in standard length, consistent with the modest size typical of Nemacheilidae. The original description separates it from Oxynoemacheilus frenatus and other Tigris-drainage congeners on a combination of characters: a complete lateral line running the length of the body, comparatively long barbels around the mouth, scales covering both flank and back, and a series of large, dark-brown, vertically elongated blotches or bars along the flank behind the base of the dorsal fin.

As in other nemacheilids, the skin carries small, deeply embedded scales rather than the larger, more visible scales of many other freshwater fish, leaving it functionally close to naked — a point that matters for medication sensitivity, discussed below. Detailed data on sexual size differences and other morphological variation are not documented in the sources available, and no suborbital spine is reported for this genus (that structure is a botiid feature, not a nemacheilid one).

Habitat

Oxynoemacheilus kentritensis is known only from the Botan River and surrounding waters of the upper Tigris drainage in southeastern Turkey — a single river system, which is typical for this genus and for Anatolian stone loaches generally, many of which are narrow-range endemics tied to one drainage or even one stream. FishBase lists it as a demersal, benthic freshwater species.

As a Nemacheilidae species from a fast-flowing Anatolian river system, it should be expected to live over clean gravel, cobble and sand substrate in cool-to-moderate, well-oxygenated, flowing water, in the manner of related Oxynoemacheilus and Barbatula species from the region — though no published habitat description with specific depth, current-speed or substrate data was found in the sources checked, and this should be treated as informed inference from the genus rather than a documented fact for this species.

Feeding

No detailed dietary study of Oxynoemacheilus kentritensis has been published; FishBase explicitly notes limited data on its diet. Stone loaches in this genus are generally bottom-foraging micro-predators, picking small invertebrates — aquatic insect larvae, worms and tiny crustaceans — from among gravel and stones in flowing water, and this species is presumed to feed similarly.

In the absence of species-specific data, the honest position is that its feeding ecology is unstudied. Any aquarium diet recommendation would need to extrapolate from close Oxynoemacheilus relatives rather than from direct evidence for this species.

Mating

No information on courtship, spawning behaviour, or sexual dimorphism has been published for this species. FishBase and the other sources consulted are explicit that reproductive data are limited or absent. Given how recently the species was described (2017) and its restriction to a single, remote river system, this is unsurprising — many narrow-range Anatolian stone loaches have simply never been studied in the field for reproductive behaviour.

Breeding

As with the rest of Nemacheilidae, Oxynoemacheilus kentritensis is presumed to be an egg-scatterer, releasing eggs over gravel and among stones in fast-flowing water with no parental care — the standard reproductive mode for stone and brook loaches. However, no breeding has been documented for this species specifically, in the wild or in captivity, and it is not known to be kept or bred in the aquarium hobby at all. Data here are genuinely sparse rather than merely under-summarized, and this article does not extend beyond what the genus-level pattern and the cited sources support.

In the aquarium

Oxynoemacheilus kentritensis is not an established aquarium species — no hobby literature, retailer listing or care-profile documentation was found for it, and a dedicated wiki page for the species notes explicitly that aquarium care requirements are not documented in public sources. It should be treated as a scientifically described but essentially unavailable and unstudied-in-captivity fish.

If it were ever kept, the safe inference from its genus and habitat would be to provide cool-to-moderate, fast-flowing, well-oxygenated, well-filtered water over a hard substrate of gravel and stones, in the manner of other riverine Oxynoemacheilus. Its near-scaleless skin, typical of Nemacheilidae, would also argue for caution with copper-based and full-strength medications, and for treating it — like most small stream loaches — as a fish that punishes stagnant, warm, poorly oxygenated setups. All of this is precautionary extrapolation, not documented species-specific guidance.

Conservation

Oxynoemacheilus kentritensis has not been formally assessed on the IUCN Red List and carries no conservation category; it is recorded here as Not Evaluated rather than assigned a guessed status. FishBase's own vulnerability metric rates it as low vulnerability to fishing pressure, with a medium resilience (an estimated population doubling time of 1.4 to 4.4 years).

As a species known only from the Botan River in the upper Tigris drainage, it shares the general exposure profile of narrow-range Anatolian stream endemics — a single river system means that local pressures such as damming, water abstraction, pollution or habitat alteration could disproportionately affect the whole population, even though no specific threat has been documented for this species in the sources reviewed. There is no evidence of aquarium-trade collection pressure; it does not appear to be part of the ornamental trade.

Sources

  1. FishBase — Oxynoemacheilus kentritensis
  2. Freyhof, Kaya & Turan (2017) — Oxynoemacheilus kentritensis, a new species from the upper Tigris drainage in Turkey, with remarks on O. frenatus (Teleostei: Nemacheilidae). Zootaxa 4258(6):551-560
  3. ResearchGate — Oxynoemacheilus kentritensis, a new species from the upper Tigris drainage in Turkey, with remarks on O. frenatus
  4. WorldFish Wiki — Oxynoemacheilus kentritensis

Last reviewed 2026-07-01.

How to cite

Aquarist Atlas (2026). Oxynoemacheilus kentritensis. Aquarist Atlas.https://www.aquaristatlas.com/loaches/oxynoemacheilus-kentritensis/

Where it has been recorded

15 georeferenced records (GBIF). Each point is a field observation or museum specimen — pan and zoom to explore where this species turns up. The coordinates come straight from GBIF and are often rounded or tied to the nearest town or river landing, so a dot can sit just beside the actual water rather than in it.

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