Loaches · Stone & brook loaches

Paraschistura naumanni

Freyhof, Sayyadzadeh, Esmaeili & Geiger, 2015

IUCNNOT EVALUATED
NEnot on the EX–LC scale
CARESNOT LISTED
Scientific size2 in5.1 cm standard length
Depthnot recorded
DietPresumed benthic micro-predator/omnivore on small invertebrates (estimated trophic level ~2.8 per FishBase); no species-specific feeding study found
BreedingEgg-scatterer over gravel/among stones in fast water; no parental care; no documented captive or aquarium breeding record
Sexual dimorphismMinimalNo dimorphism data found in the sources consulted
PhotographsSee photosGoogle Images →

Paraschistura naumanni is a small stone loach described only in 2015, known from a handful of drainages in southern Iran. It belongs to Nemacheilidae, the largest loach family and the one that supplies the aquarium hobby's true "stone" or "brook" loaches — slender, bottom-hugging micro-predators built for cool, fast, oxygen-rich streams. Reaching barely 2 in, it is one of the smallest loaches in this atlas and, as a recently described regional endemic, one of the most data-sparse: there is no aquarium trade record, no confirmed water chemistry, and no IUCN assessment for the species. What follows is built honestly on that thin foundation rather than padded with guesswork.

What's in the name

Paraschistura naumannipair-ah-SHIS-tuh-rah now-MAN-eye

Paraschistura
  • paraGreekbeside, near
  • Schisturagenus namethe related nemacheilid genus it sits alongside — together 'near Schistura'
naumanni
  • Naumannpersonal namehonouring Clas M. Naumann zu Königsbrück (1939–2004), former director of the Zoologisches Forschungsmuseum Alexander Koenig

Taxonomy & naming

Paraschistura naumanni was formally described in 2015 by Jörg Freyhof, Hamid Reza Sayyadzadeh, Hamid Reza Esmaeili and Matthias Geiger, part of a wave of taxonomic work that has split apart the once-unwieldy Nemacheilus/Noemacheilus catch-all into a mosaic of narrower genera — Schistura, Triplophysa, Barbatula, Paracobitis and Paraschistura among them. The Catalog of Fishes, the standing authority for valid fish names, recognises Paraschistura naumanni as a distinct species in the genus Paraschistura, family Nemacheilidae.

The species epithet honours Clas M. Naumann zu Königsbrück (1939–2004), a former director of the Zoologisches Forschungsmuseum Alexander Koenig (ZFMK) in Bonn, a common form of eponymous tribute in recent ichthyological description papers. Because the species was named this recently, older literature and any pre-2015 hobby records for Iranian stone loaches from these drainages would necessarily use a different, now-superseded name or none at all.

Morphology

Paraschistura naumanni is a small, slender nemacheilid loach, reaching a maximum recorded length of only about 2 in standard length. Like other stone and brook loaches it has an elongate, sub-cylindrical body suited to holding position on stream substrate, a ventrally flattened head and underslung mouth for browsing the streambed, and barbels around the mouth for sensing food in the current.

As is typical for the family, the skin carries very small, deeply embedded scales — effectively naked to casual inspection — a trait that matters for how the fish should be handled and medicated. Many nemacheilids, including species in this genus, also bear a small erectile spine below the eye, though this is far less developed than in the spined botiid loaches. Detailed morphometric and colour-pattern data beyond the original description are not available from the sources consulted here, so further description should not be assumed.

Habitat

The species is endemic to a cluster of drainages in southern Iran: it has been recorded from the Kol drainage, the Maharlo basin, the Helleh drainage and the upper Mond drainage. These are freshwater systems on the Iranian plateau and its southern flanks, part of a region known for a distinct and often narrowly endemic freshwater fish fauna shaped by isolated basins and seasonal, sometimes intermittent, flow.

As a demersal (bottom-dwelling) freshwater fish in this genus, Paraschistura naumanni is presumed to live in flowing, well-oxygenated stream habitat typical of Nemacheilidae, holding station over gravel, sand or rock substrate. Specific data on the exact stream character — flow rate, substrate composition, elevation, or seasonal variability — at each locality was not found in the sources reviewed, so this should be treated as an inference from the family and region rather than a confirmed description.

Feeding

No dietary study specific to Paraschistura naumanni was found in the sources consulted, though FishBase lists an estimated trophic level of roughly 2.8, consistent with a low-level micro-predator or omnivore. This matches the broader Nemacheilidae pattern: small stone and brook loaches typically forage over the streambed for small invertebrates — insect larvae, tiny crustaceans and other benthic prey — picking through gravel and sediment in fast-flowing water.

In the absence of species-specific feeding data, keepers and researchers should default to what is known for the family rather than assume anything more specific. Where this species or close relatives are kept, small sinking live or frozen foods (bloodworm, daphnia, brine shrimp) would be the expected match for a benthic micro-predator, but this is an inference, not a documented feeding record.

Mating

No information on courtship, sexual dimorphism, or spawning behaviour for Paraschistura naumanni was found in the sources consulted. This is unsurprising for a species described only in 2015 from wild survey material rather than aquarium or long-term field study; reproductive biology for many narrow-range Nemacheilidae endemics remains unstudied.

What can be said comes from the family pattern: nemacheilid stone and brook loaches are generally egg-scatterers, releasing eggs over gravel or among stones in flowing water rather than forming pairs, guarding a cave, or mouthbrooding. There is no basis in the available sources to describe a species-specific mating system for Paraschistura naumanni beyond this general family expectation.

Breeding

Paraschistura naumanni has no documented aquarium or captive breeding history in the sources reviewed, and this is consistent with the broader picture for stone and brook loaches: most Nemacheilidae are rarely or never bred in home aquaria, and this species — a narrow-range Iranian endemic described only in 2015 with apparently no established aquarium presence — has no known husbandry or breeding record at all.

Following the pattern documented for the family, the expected breeding mode is egg-scattering over gravel or among stones in fast-flowing water, with no parental care after spawning. This should be read as an inference from Nemacheilidae generally, not as a confirmed observation for this species. Given the total absence of trade or captive records, breeding this species is not something a hobbyist keeper should currently expect to attempt.

In the aquarium

There is no evidence in the sources consulted that Paraschistura naumanni is established, or has ever been established, in the aquarium hobby. No care guide, water-chemistry record, or trade listing was found. As a very recently described (2015), narrow-range Iranian stream endemic reaching only about 2 in, it is the kind of species that may occasionally reach specialist collectors through targeted field collecting but has no track record of ordinary retail availability.

Any keeper who did obtain this species should apply the general precautions that hold across Nemacheilidae: the near-scaleless skin common to the family makes these fish sensitive to copper and to full-strength medications, so gentler, reduced-dose treatment is prudent if disease treatment is ever needed. As a small stream-dwelling micro-predator, it should be assumed to want clean, well-oxygenated, flowing water with a fine gravel or sand substrate rather than a still, warm community tank — but without confirmed temperature or pH data for this species specifically, any aquarium setup would be an extrapolation from its wild habitat and its relatives, not a documented protocol.

Conservation

Paraschistura naumanni has not been assessed on the IUCN Red List; its status here is recorded as Not Evaluated (NE) rather than guessed at. This is common for recently described, narrow-range freshwater endemics, which often lag well behind their description in receiving a formal conservation assessment.

As a species restricted to a small number of drainages in southern Iran (Kol, Maharlo, Helleh and upper Mond), it fits the broader profile of many Iranian plateau freshwater fishes: narrow-range endemics in basins that can be vulnerable to water abstraction, damming and drought. No specific threat assessment or population trend data was found in the sources consulted, so no claim beyond its Not Evaluated status and its narrow known range should be made.

Also from the Kol drainage

Sources

  1. FishBase — Paraschistura naumanni
  2. Wikispecies — Paraschistura naumanni

Last reviewed 2026-07-01.

How to cite

Aquarist Atlas (2026). Paraschistura naumanni. Aquarist Atlas.https://www.aquaristatlas.com/loaches/paraschistura-naumanni/

Where it has been recorded

6 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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