Taxonomy & naming
Oxynoemacheilus shehabi was described by Jörg Freyhof and Matthias F. Geiger of the Museum für Naturkunde Berlin in January 2021, in Zootaxa 4908(4): 571–583. The holotype, ZFMK ICH 124181, is a 2 in SL specimen collected from the upper Orontes River in southern Syria. The genus Oxynoemacheilus is one of several segregates carved out of the old, catch-all Nemacheilus/Noemacheilus over the past two decades as the Cobitoidea has been repeatedly revised — a reshuffle this family has seen more than most, and one the Catalog of Fishes continues to govern for valid names.
The describers used DNA barcoding alongside morphology to separate the new species from its relatives: the mitochondrial COI sequence differs from that of Oxynoemacheilus "seyhanicola" by a K2P genetic distance of 3.8%, a gap consistent with species-level separation in this genus. The species epithet honours a person associated with the fish's discovery or study, in the tradition common to recent Nemacheilidae descriptions from the Levant, though the cited sources do not spell out the full dedication.
Morphology
This is a small, slender stone loach, with the 2 in SL holotype giving a sense of its modest adult size. The original description notes a complete lateral line running the length of the body, a deeply emarginate (forked) caudal fin, and a notably narrow caudal peduncle — features that, taken together, point to a fish adapted for efficient swimming against current rather than for slow foraging in still water.
Males carry a suborbital groove, the housing for the small, erectile spine found below the eye in many nemacheilid and related loaches, and the species has a well-developed pelvic axillary lobe, a small flap of skin at the base of the pelvic fin used in Nemacheilidae taxonomy. The flanks show 5–7 dark-brown bars, a fairly typical patterning for a stone loach of this group. As in other Nemacheilidae, the skin is effectively scaleless or bears only fine, deeply embedded scales, a trait that carries real consequences for how the fish should be handled and medicated in captivity.
Habitat
Oxynoemacheilus shehabi is known only from the upper Orontes River system in southern Syria, making it a genuine single-river endemic as currently understood. Nemacheilidae as a family are characteristic of clear, well-oxygenated streams and rivers with gravel or sandy bottoms, and they are frequently used as water-quality indicator species precisely because they are sensitive to pollution and to low dissolved oxygen — there is no reason to expect this species to differ from that pattern.
The available sources do not report specific temperature, pH or flow measurements taken at the type locality, so no numeric water-chemistry envelope can be given with confidence. What can be said, consistent with the genus and family, is that this is a fish of cool-to-moderate, fast-flowing, clear stream water over a hard substrate — not a warm, still, or blackwater environment. Given the political and logistical difficulty of fieldwork in Syria since the species' 2021 description, the population's current status and any pressures on the upper Orontes are effectively unstudied in the accessible literature.
Feeding
No feeding study specific to Oxynoemacheilus shehabi has been located. Based on the well-documented ecology of Nemacheilidae generally, it is reasonable to describe it as a bottom-foraging micro-predator: a fish that works over gravel and sand picking off small invertebrates, insect larvae and crustaceans, the standard diet recorded for stone loaches across the family.
In captivity, stone loaches of this kind typically accept small live and frozen foods — bloodworm, brine shrimp, chopped invertebrates — readily, and take sinking pellets or wafers less readily than they take anything that moves or settles directly on the substrate; flake left floating at the surface is often ignored by fish built to feed head-down in current.
Mating
Nothing has been published on courtship or spawning behaviour in Oxynoemacheilus shehabi; the 2021 description is a taxonomic paper focused on distinguishing the species from its relatives, not a life-history study. No external sexual dimorphism is documented in the available sources beyond the male suborbital groove noted in the description, which is a taxonomic character rather than a breeding signal.
Across Nemacheilidae generally, spawning is not tied to elaborate courtship or pairing behaviour but to seasonal cues of rising, fast-flowing water, when ripe fish scatter eggs over gravel. There is no evidence this species departs from that pattern, but it should be stated plainly: this is inference from the family, not observation of the species.
Breeding
As with the great majority of small stone loaches in Nemacheilidae, Oxynoemacheilus shehabi is not known to have been bred in the aquarium, and no spawning account — wild or captive — appears in the literature reviewed here. The expected mode, following the family, is an egg-scatterer that releases eggs over gravel or among stones in fast-flowing water with no parental care afterward.
Given that the species was described only in 2021 from a single Syrian river system and does not appear to be established in the aquarium trade, data on its reproduction is sparse to the point of nonexistence. Any care sheet claiming detailed breeding protocols for this species should be treated with real skepticism; the honest statement is that this is essentially unknown territory.
In the aquarium
Oxynoemacheilus shehabi is not established in the aquarium hobby, and no trade name, import history or care consensus exists for it in the sources reviewed. Any care advice here has to be extrapolated cautiously from its family rather than drawn from hobbyist experience with the species itself.
Were it to appear in the trade, the expectations set by Nemacheilidae generally would apply: cool-to-moderate, clean, fast-moving, highly oxygenated water over a gravel or sand substrate with good current; a scaleless or near-scaleless body that makes it sensitive to copper-based medications and full-strength treatments, calling for gentler, reduced-dose approaches; and a diet of small live or frozen foods offered where the fish forages, at the bottom, rather than left to float. Until it is actually kept and reported on by aquarists, this remains informed inference rather than a tested care profile.
Conservation
Oxynoemacheilus shehabi has not been evaluated on the IUCN Red List. Given that it was described only in January 2021, this is unsurprising — new stream endemics often go years before a formal assessment is undertaken, and the ongoing conflict and access difficulties in Syria make fieldwork on its single known river system, the upper Orontes, especially hard to conduct.
As a single-river endemic in a country facing severe environmental and infrastructural pressures, the species is plausibly vulnerable to habitat degradation, water abstraction or pollution, but no population assessment, trend data or threat analysis has been published to confirm or quantify that risk. The correct and honest status here is Not Evaluated — data sparse — rather than any inferred category.