Taxonomy & naming
Cobitis amphilekta was formally described by Yulia Vasil'eva and Victor Vasil'ev in 2012 in the Journal of Ichthyology, as part of a wider revision of spined loaches from the Caspian Sea basin. It belongs to the family Cobitidae — the true spined and pond loaches — within the genus Cobitis, the temperate Eurasian loaches that give the family its old common name.
The species epithet amphilekta means "confused" or "disputed" in Greek, a direct reference to its taxonomic history: specimens now recognized as this species had previously been assigned to as many as three different nominal species across two genera before the 2012 revision untangled them. This kind of cryptic-species problem is common in Cobitis, where closely related populations look almost identical externally and are best separated by close anatomical and genetic study. The Catalog of Fishes, the standing authority for valid fish names, recognizes Cobitis amphilekta as a distinct, valid species.
Morphology
Like every member of the family Cobitidae, Cobitis amphilekta carries the erectile suborbital spine that names the group — a small, sharp, forked spine hidden in a pocket of skin below the eye that the fish can flick out, chiefly in defense or when handled. Its body is elongated and only lightly built, covered in tiny, deeply embedded scales that leave the skin functionally near-naked — a trait shared across the family and one with real consequences for how the fish should be treated in captivity.
As with other members of its genus, Cobitis amphilekta is a small, slender, bottom-hugging fish rather than a robust or showy one; detailed morphometric distinctions from its closest relatives (including other Caspian-basin Cobitis) are subtle and were the basis of its original description. This is a temperate, coldwater species, not a tropical one — a distinction that matters for anyone trying to picture how it lives.
Habitat
Cobitis amphilekta is endemic to the Caspian Sea basin in Azerbaijan, known from Kyzylagach Bay (also referenced in the literature as Maly Kyzylagach Bay) in the southwestern Caspian and from the Kumbashi River drainage. Its type locality is Kyzylagach Bay itself. This places it firmly in the temperate lowland waters of the western Caspian coast, not in any tropical river system.
Spined loaches of the genus Cobitis are typically fish of still or slow-flowing water over sandy or muddy bottoms, often with some vegetation, and the wider genus is known to inhabit cool temperate waters in roughly the 57–64 °F range. Cobitis amphilekta almost certainly followed this same pattern of habitat use before its apparent decline — a coastal, bay-and-river-drainage fish of soft sediment rather than fast open channels.
Feeding
As a member of the sand-sifting Cobitidae, Cobitis amphilekta is best understood as a benthic omnivore: species in this genus feed by sifting through sand and soft mud for small invertebrates such as worms, insect larvae and tiny crustaceans, along with organic detritus. A soft substrate is not incidental to this feeding style — it is how the fish forages at all, and it is a detail that would matter enormously to any attempt to keep the species, though no such attempt is documented.
No dedicated dietary study of Cobitis amphilekta itself is available; the diet described here follows the well-documented feeding ecology of the wider Cobitis genus, to which this species conforms in body plan and habitat.
Mating
No spawning behavior specific to Cobitis amphilekta has been documented — unsurprising for a species that has not been confidently observed since the 1930s. What is known comes from the genus as a whole: temperate spined loaches typically ripen and spawn in spring as water temperatures rise, scattering eggs rather than pairing off or guarding a nest site.
There is no suborbital-spine display, cave-guarding or mouthbrooding behavior in this family — those belong to entirely different fish groups. Cobitis is an egg-scattering genus, and there is no reason to expect Cobitis amphilekta departed from that pattern.
Breeding
Cobitis amphilekta has never been bred in the aquarium — there is no record of the species even being kept, let alone spawned, in captivity. Based on the genus, the expected mode is that of a typical spined loach: adults scatter adhesive eggs among aquatic plants, generally in spring, with no parental care afterward.
This pattern has been achieved with several other temperate Cobitidae — including other Cobitis species, Sabanejewia, and the pond- and tank-spawned dojo or weather loach, Misgurnus — under cool, unheated conditions that mimic a natural spring rise in temperature. Whether Cobitis amphilekta could be bred the same way is unknown and, given its likely extinction in the wild and complete absence from the hobby, probably moot. The honest summary is: essentially never bred, with no parental care expected if it were.
In the aquarium
Cobitis amphilekta is not part of the aquarium trade and there are no keeping records to draw on. It has not been reported in the wild since the 1930s and is treated by assessors as possibly extinct, so any care guidance here can only extrapolate from its temperate Cobitis relatives rather than from direct experience with this species.
Were a related Caspian-basin spined loach ever kept, the general template for cool-water Cobitidae would apply: an unheated or lightly heated tank rather than a tropical setup, a soft sand substrate that lets the fish sift and burrow naturally, and cautious use of medications, since the near-scaleless skin typical of this family makes spined loaches unusually sensitive to copper-based treatments and full-strength doses. None of this is confirmed for Cobitis amphilekta specifically — it is offered only as the closest honest analogy available.
Conservation
The IUCN Red List assesses Cobitis amphilekta as Data Deficient. The species is known only from Kyzylagach Bay and the Kumbashi River drainage in the Caspian Sea basin of Azerbaijan, and has not been confidently recorded since the 1930s. Assessors note it may have been displaced in parts of its range, including in the middle reaches of the Kura River, by the related species Cobitis saniae.
Given the lack of recent records despite its very restricted, well-defined range, there is real concern that Cobitis amphilekta is extinct or has been for decades — a fate that would make it one of the more obscure losses among the Caspian basin's freshwater fishes. It has no presence in the aquarium trade, so there is no trade-driven pressure on the species; whatever drove its apparent disappearance predates and is unrelated to the ornamental fish industry.