Taxonomy & naming
Indoreonectes rajeevi was described in 2021 by Kumkar, Pise, Gorule, Verma & Kalous in the journal Vertebrate Zoology, from a holotype measuring 2 in standard length. The genus Indoreonectes itself is a relatively narrow slice of the old, sprawling Nemacheilus/Noemacheilus complex — the ETYFish Project traces the name to a blend of "Indo" and Oreonectes, another nemacheilid genus, essentially marking it as an Indian counterpart to Oreonectes. The species epithet honours the Indian ichthyologist Rajeev Raghavan, recognising his contributions to the study of South Asian freshwater fishes.
The family Nemacheilidae — the stone or brook loaches — is by far the largest loach family, with the bulk of its diversity concentrated across South, Southeast and East Asia. Genus-level boundaries within it have shifted repeatedly as older catch-all genera such as Nemacheilus and Noemacheilus have been split apart on genetic and morphological grounds; Indoreonectes is one of the more recently erected of these segregate genera, and the Catalog of Fishes is the authority for its current placement.
Morphology
The original description characterises Indoreonectes rajeevi by a set of fine anatomical details rather than any bold, showy pattern: distinct black markings on the lower lip, an absence of the dorsal hump seen in some relatives, 36 vertebrae, and a dorsal-fin insertion positioned between the 12th and 13th abdominal vertebra. The holotype was 2 in standard length, consistent with the generally small, slender body plan typical of stone loaches in this family.
As in other nemacheilids, the species almost certainly carries the family's signature erectile suborbital spine — a small, sharp spine tucked in a groove beneath the eye that can be flicked out defensively — along with the near-scaleless, delicate skin typical of the group. No dedicated study of the species' colouration or fin-ray counts beyond the type description is available, so further morphological detail should be treated as data-sparse rather than assumed.
Habitat
Indoreonectes rajeevi is known only from its type locality: the Hiranyakeshi, a tributary of the Krishna River, at Amboli in the Western Ghats of Maharashtra, India. The type series was collected from a slow-flowing, clear stream running over a mixed substrate of boulders, pebbles and mud — a classic hillstream setting in the biodiversity-rich Western Ghats, one of the world's recognised freshwater-fish hotspots.
No broader range has been documented; as a single-locality endemic described only in 2021, its full distribution, seasonal water conditions and tolerance limits remain unstudied. Stone loaches in this family generally favour cool-to-moderate, well-oxygenated, flowing water, and there is no indication this species departs from that pattern, but specific figures for the Hiranyakeshi stream itself have not been published.
Feeding
No feeding study exists for Indoreonectes rajeevi specifically, but the family pattern is well established and there is no reason to expect this species to differ: nemacheilid stone loaches are benthic micro-predators, working over stream-bed stones and gravel for small invertebrates such as insect larvae and tiny crustaceans, alongside the aufwuchs — the biofilm layer of algae and microorganisms — that coats submerged rock in flowing water.
In the near-total absence of aquarium experience with this exact species, any care guidance on diet has to be extrapolated from its genus and family rather than drawn from direct observation, and should be treated accordingly.
Mating
Nothing has been published on courtship, sexual dimorphism or spawning behaviour in Indoreonectes rajeevi. The species is known from a small type series collected at a single site, and the 2021 description focuses on the diagnostic anatomy needed to distinguish it from its closest relatives rather than on life history. As with feeding, any expectations about pairing or breeding condition have to be drawn cautiously from the wider stone-loach family rather than from direct evidence for this species.
Breeding
There is no record of Indoreonectes rajeevi being bred, or even kept, in the aquarium hobby. Stone and brook loaches of Nemacheilidae are, as a family, egg-scatterers: ripe fish release eggs over gravel and among stones in fast-flowing water with no parental care, and captive spawnings of most species in this family are rare to nonexistent. Given that this species was described only in 2021 from a single Western Ghats stream and has no documented aquarium history, the honest summary is that its reproductive biology is essentially unknown outside the generic pattern for its family.
In the aquarium
Indoreonectes rajeevi is not established in the aquarium trade, and there is no record of hobbyist experience with it. Any care approach would have to follow the general template for small nemacheilid stone loaches: cool-to-moderate, clear, well-oxygenated, flowing water over a stone-and-gravel substrate with a mature biofilm surface for grazing, gentle enough tankmates, and — as with all nearly-scaleless loaches — real caution with copper-based and full-strength medications, since the family's thin skin makes it unusually sensitive to treatments that other fish tolerate easily.
Given the species is known from a single small Western Ghats stream and has no aquarium track record, it should be treated as a scientific curiosity rather than a fish to seek out; there is currently no responsible sourcing pathway for it in the hobby.
Conservation
Indoreonectes rajeevi has not been formally assessed on the IUCN Red List and is recorded here as Not Evaluated. It is known only from its 2021 type description at a single locality — the Hiranyakeshi tributary of the Krishna River at Amboli, Maharashtra — which is exactly the profile of many recently described Western Ghats stream fishes: a narrow known range that, once surveyed further, often supports a Data Deficient or threatened-category listing. Until a formal assessment is carried out, no status beyond Not Evaluated should be asserted.
The Western Ghats are a globally recognised freshwater-biodiversity hotspot under mounting pressure from stream modification, water abstraction and land-use change, and single-locality endemics like this one are inherently vulnerable to any disturbance at their one known site.