Taxonomy & naming
Schistura crocotula was formally described in 2013 by Kredsuda Plongsesthee, Maurice Kottelat and Ronald Beamish in Ichthyological Exploration of Freshwaters (volume 24, issue 2, pages 171–178), as part of ongoing work resolving the diversity of small loaches in Thailand. It belongs to the genus Schistura, within the family Nemacheilidae — the stone and brook loaches, the largest family of true loaches and one that has absorbed many species once placed in the old catch-all genera Nemacheilus and Noemacheilus.
The Catalog of Fishes (Eschmeyer, CAS) is the authority for the valid name, and it stands as originally described: Schistura crocotula, with no synonyms or subsequent recombination on record. As with many recently described nemacheilids, little has been published on the species since its description, and it has not attracted attention from the aquarium trade or from later taxonomic revision.
Morphology
In life, Schistura crocotula shows a striking saffron-orange ground colour, giving way to grey in preserved specimens, crossed by six to eleven regular dark brown bars — the first of which, behind the head, is noticeably wider than the rest. Two of the bars sit beneath the dorsal fin, and a thick black bar marks the base of the caudal fin, a pattern typical of the genus's banded species group. Like other Schistura it is a small, elongate, laterally compressed fish built for holding station in current, with the erectile suborbital spine characteristic of true loaches tucked in a groove below the eye, and skin that is effectively naked — nemacheilids carry only minute, deeply embedded scales rather than the coarse scaling seen in many other fish families.
No maximum length has been published for the species, which is consistent with how little post-description work exists; small nemacheilid Schistura in the region typically run from around 1–2.5 in, but that range should be read as a general genus expectation rather than a measured figure for this species.
Habitat
The species is known only from peninsular Thailand, with its type locality in the Khanan River at Bangsapan, Prachuap Khiri Khan Province, and a second confirmed record from the nearby Pranburi River system in the same province. Both are part of the clear, fast-flowing stream habitat typical of nemacheilid loaches — cool-to-moderate, well-oxygenated water running over gravel, sand and rock in foothill and lowland stream reaches.
No published water-chemistry or temperature measurements accompany the description, so specific figures for this population are not available. What can be said with confidence, based on the genus and habitat type, is that this is a fast-water stream fish, not a still-water or blackwater species — the kind of clear, oxygen-rich flow that stone loaches depend on for both foraging and respiration.
Feeding
As with the great majority of Schistura, S. crocotula is presumed to be a bottom-foraging micro-predator, picking small invertebrates — aquatic insect larvae, worms and tiny crustaceans — from among gravel and stones in fast-flowing water. This is standard nemacheilid feeding ecology rather than anything documented specifically for this species, since no dietary study has been published.
No aquarium feeding record exists for S. crocotula itself, but genus-level experience with Schistura indicates they take small live and frozen foods such as bloodworm and daphnia readily, and often ignore dry flake, being adapted to hunting live prey off the streambed rather than picking food from the water column.
Mating
Nothing has been published on courtship, sexing or spawning behaviour in Schistura crocotula. No external sexual dimorphism has been described for the species, which is not unusual for a nemacheilid known from a small number of preserved specimens rather than from live observation or captive study.
Breeding
There is no breeding record for this species in the aquarium or in the wild beyond its formal description. In line with what is known for stone and brook loaches generally, any reproduction would be expected to follow the Nemacheilidae pattern: an egg-scatterer releasing eggs over gravel or among stones in fast-flowing water, with no parental care. Stone loaches of this kind are rarely bred in captivity even where they are established in the hobby, and Schistura crocotula has no aquarium history at all, so this should be read as a genus-level expectation rather than an observed fact for the species.
In the aquarium
Schistura crocotula is not established in the aquarium trade, and there is no husbandry record to draw on. It has never been widely collected or exported, and its distribution is limited to two river systems in a single Thai province — a narrow range that argues strongly against any wild collection for the trade in the absence of clear population data.
Were a keeper to encounter this or a similar undescribed-locality Schistura, genus-level care would point toward a well-oxygenated, flowing, cool-to-moderate-temperature tank with a hard substrate of sand and rounded gravel, since these are stream fish that do poorly in warm, still water. As with all nemacheilids, the near-scaleless skin makes them sensitive to copper-based medications and full-strength treatments, so any medicating should be done cautiously and at reduced dose.
Conservation
Schistura crocotula has not been evaluated on the IUCN Red List. Given its description in 2013 and its narrow known range — two river systems in Prachuap Khiri Khan Province, peninsular Thailand — it fits the profile of many small nemacheilid stream endemics that remain data-deficient or unassessed simply because no dedicated conservation review has been undertaken. No population trend, threat assessment or trade pressure has been documented for the species, and until one is, the honest status is Not Evaluated rather than an inferred category.