Taxonomy & naming
Yunnanilus elakatis was described by Cao and Zhu in 1989. It belongs to the genus Yunnanilus, a large assemblage of small stone loaches in the family Nemacheilidae — itself the largest family of true loaches, encompassing the slender, clear-stream "brook loaches" of Asia and beyond. Older literature and some databases have placed the species under the historic family name Balitoridae, a broader grouping that has since been split; the Catalog of Fishes governs current usage, and this species is retained here under its original genus, Yunnanilus.
The specific epithet elakatis derives from Greek and refers to the fish's spindle-like body shape — a slender, tapering form typical of many small nemacheilid loaches adapted to holding position in flowing water. The species is known in Mandarin by the common names 紡綞雲南鰍 / 纺缍云南鳅, both referencing the same spindle-shaped body.
Morphology
Yunnanilus elakatis is a small, slender stone loach with the elongated, laterally compact body typical of the genus. Meristic counts recorded for the species include 12–13 dorsal soft rays and 8–9 anal soft rays. Like other nemacheilids it is a benthic fish built for clinging to and moving over stream substrate rather than for open-water swimming.
Detailed morphological description beyond these counts and the type material is limited in the available literature; as with many small-range Yunnanilus species, comprehensive anatomical and coloration data have not been widely published outside the original taxonomic description.
Habitat
The species is endemic to southeastern China, recorded from the Pearl River (Zhu Jiang) basin in Yunnan and Guangxi provinces, with its type locality in Yiliang County near Kunming. It is a demersal freshwater fish found in rivers, streams and lakes within this drainage.
As a stone and brook loach, Yunnanilus elakatis is expected to favor the clear, flowing, well-oxygenated water typical of the genus, though specific habitat parameters — substrate, vegetation, exact flow and temperature range at collection sites — have not been documented in detail in the sources available for this profile. Given its range in the Yunnan plateau region, it likely experiences cooler conditions than lowland tropical loaches; keepers should treat this as an indication rather than a confirmed figure.
Feeding
Yunnanilus loaches are generally bottom-foraging micro-predators, working the substrate of streams and rivers for small invertebrates and insect larvae rather than grazing algae or taking large prey. Y. elakatis is presumed to follow this pattern typical of its genus, though no species-specific dietary study is available.
In the aquarium, related Yunnanilus species accept small live and frozen foods such as bloodworm and daphnia, along with sinking pellets, and may largely ignore floating flake given their bottom-oriented foraging habit. A keeper should plan feeding around the bottom of the tank and offer a varied diet of small invertebrate-type foods.
Mating
No courtship or spawning behavior specific to Yunnanilus elakatis has been documented in the available literature. Data on sexual dimorphism for this species is likewise absent from the sources consulted; this profile does not assert a visible difference between males and females.
Breeding
As with the great majority of stone and brook loaches, Yunnanilus elakatis has not been reported bred in the home aquarium, and no breeding account for this specific species could be found. Nemacheilid loaches in general are egg-scatterers, releasing eggs over gravel and among stones in flowing water with no parental care, and this is the reasonable expectation for this species' reproductive mode by analogy with its relatives — but it should be read as an inference from the genus rather than a confirmed observation. Data for this species remains sparse, and a keeper should not expect to breed it.
In the aquarium
Yunnanilus elakatis is very rarely, if ever, seen in the aquarium trade, and dedicated care information for the species is essentially absent from the hobby literature. General care guidance for the genus applies with caution: Yunnanilus loaches are small, social bottom-dwellers best kept in a group rather than singly, in a tank with clean, well-oxygenated, flowing water and a fine, soft substrate that lets them forage naturally.
As with other nemacheilid and true loaches, this species is expected to be near-scaleless and correspondingly sensitive to copper-based medications and full-strength treatments; any medicating should be done cautiously and at reduced dose. Given the total absence of confirmed trade or husbandry records for this exact species, any tank offered to it should be conservatively sized and furnished for a small, cool-to-moderate flowing-water stream loach rather than assumed from generic tropical-community norms.
Conservation
Yunnanilus elakatis has not been formally assessed on the IUCN Red List, and no primary IUCN assessment page for the species could be located; it is treated here as Not Evaluated. One secondary source referenced an "endangered" classification tied to habitat reduction and environmental pressure in Yunnan, but the assessment year and primary source for that status were not clearly identified, so it should not be taken as a confirmed IUCN rating — a keeper or researcher wanting a definitive status should consult the primary IUCN Red List page directly.
As a narrow-range endemic of the Pearl River basin in Yunnan and Guangxi, the species is plausibly exposed to the same pressures affecting many small-range Chinese stream fishes — damming, pollution and habitat alteration — but no species-specific conservation study is available to confirm the scale of any decline.