Taxonomy & naming
Bujurquina omagua was described by Oldřich Říčan and Štěpánka Říčanová in 2023 in the European Journal of Taxonomy (vol. 870, pp. 167–201), in a paper framed around the biogeography of a hypothesized 'reverse-flowing' paleoriver on the Iquitos arch. The genus Bujurquina was erected by Sven O. Kullander in 1986 (type species Bujurquina moriorum) to hold an assemblage of biparentally custodial, primitively (delayed) mouthbrooding acaras that had previously been lumped into Aequidens; omagua brings the genus to roughly two dozen described species, almost all of them western-Amazonian. In the phylogeny accompanying the description, Bujurquina splits into a 'Northern' and a 'Southern' clade, and omagua falls in the Northern group together with neighbours such as Bujurquina syspilus, Bujurquina peregrinabunda and Bujurquina moriorum. The holotype is an adult male of 4 in standard length, MUSM 70225, held at the Museo de Historia Natural de la Universidad Nacional Mayor de San Marcos in Lima; it was collected on 28 June 2018 by Říčan in the headwaters of the Quebrada Sabalillo near Oran. Before it was named, the fish circulated in the molecular literature as 'Bujurquina sp. Oran' and 'Bujurquina sp. Peru 1' (Říčan et al. 2022). The Catalog of Fishes and FishBase both treat the name as valid. The specific epithet honours the Omagua, the indigenous people who at the time of first European contact in the sixteenth century dominated the banks of the Amazon from above the mouth of the Río Negro well into present-day Peru — it is a noun in apposition, not a Latin adjective. There is no established English common name; the species is too new and too localized to have entered the aquarium trade under a settled label.
Morphology
This is a small cichlid: the type series tops out at 4 in standard length (a 4 in paratype), and FishBase carries the same 4 in SL maximum. The body is deep and laterally compressed — body depth averages about 45% of standard length, among the deepest in the genus — carried on a robust, large-eyed head with notably the longest snout of any Bujurquina (mean 15.5% of SL, with no overlap against the next-longest species). In life the lower head, cheek and gill cover are washed yellow-orange and overlaid with opalescent golden-to-azure lines and spots, with up to four well-defined lines running between the eye and the corner of the mouth. The diagnostic markings are a curved suborbital stripe that bends from behind the eye forward and then down to a diffuse blotch at its lower end (juveniles and subadults instead show a straight, diagonal stripe starting below the eye — an ontogenetic change the authors emphasize), a continuous, strongly black midlateral band that is broad at the head and tapers toward the tail, and five body bars plus a caudal-peduncle bar and blotch. The spiny part of the dorsal fin carries a single thin diagonal black line per membrane (two lines in the holotype and the largest adults), which separates it from congeners that show blotches, multiple thick lines, or a pair of horizontal bands. Internally it is the most delicate-jawed species in the genus: the lower pharyngeal tooth plate is the shortest, with the widest 'horns' and one of the smallest tooth-bearing areas, hinting at a fine-particle or soft-prey diet rather than crushing. The original description does not document sexual dimorphism for this species specifically; across Bujurquina the sexes are only weakly dimorphic, males tending to grow somewhat larger and, in several species, to develop produced filaments (streamers) on the tail — a reasonable but unconfirmed expectation here.
Habitat
Bujurquina omagua is known only from the Sabalillo and Oran creeks, two small drainages that empty into the Amazon on either side of Oran village, situated on the first high ground just downstream of the Napo mouth (District Las Amazonas, Maynas Province, Loreto, Peru). The collection sites sit at roughly 246–384 ft above sea level. These are narrow terra-firme rainforest streams — about 7 ft wide, shallow at well under 3 ft except in scattered deeper pools — with deep mud and accumulated leaf litter and debris on the bottom, blackish (clear-water with a blackish tinge) acidic-looking water, and only weak to moderate current. Tellingly, the species was not found in the main, muddy-water channels of the Oran and Sabalillo creeks or in their lower reaches, where the widespread floodplain species Bujurquina syspilus turns up instead; omagua appears confined to the clearer, blackwater terra-firme headwaters above the inundation zone. The describers interpret this as the rule rather than the exception for the genus: lowland western Amazonia tends to hold a widespread floodplain Bujurquina along the main rivers plus localized endemics isolated in the streams of terra-firme 'islands' that the seasonally flooded main channels effectively cut off. The original paper reports no instrument water-chemistry values (temperature, pH, conductivity); the figures used here for the fact panel are the genus-typical warm, soft, mildly acidic blackwater of the western-Amazonian lowlands and should be read as habitat-inferred, not measured at the type locality.
Feeding
No gut-content study has been published for Bujurquina omagua, so its diet is inferred from its anatomy and from what is known of the genus. FishBase places it at an estimated trophic level of about 3.5, in the range expected of a small benthic omnivore. Bujurquina are generalist acaras that work the stream bed and leaf litter for small invertebrates, plant and detrital matter, and the soft material trapped in mud and debris — exactly the substrate that floors omagua's streams. The species' unusually delicate, fine-toothed lower pharyngeal jaw — the most lightly built in the genus — argues against a diet of hard-shelled prey and is more consistent with soft invertebrates and fine particulate material. In its leaf-littered headwater community it most plausibly functions as a small benthic micro-invertivore and detritivore rather than a predator of any size.
Mating
Direct courtship observations for Bujurquina omagua have not been published, but the genus has a consistent and well-documented reproductive pattern that almost certainly applies. Bujurquina form monogamous pairs in which both sexes share territory defence and brood care — Kullander's 1986 definition of the genus was built explicitly around this 'biparentally custodial' habit. Pairs select and clean a spawning site (characteristically a leaf or other movable surface) and defend a modest territory around it through a prolonged courtship. In the wild this plays out in small, structurally complex streams full of submerged litter, which provide both spawning surfaces and cover for a pair guarding young. Aggression in these acaras is moderate by cichlid standards and largely confined to the breeding territory, rather than the sustained, lethal intolerance seen in some larger Neotropical cichlids.
Breeding
Although the breeding of Bujurquina omagua has not itself been documented, the reproductive mode of Bujurquina is one of the genus's defining traits and is well established for its close relatives. These are biparental delayed (larvophilic) mouthbrooders — sometimes called 'leaf' mouthbrooders. The pair spawns onto a leaf or similarly movable surface and both parents guard the eggs in place; once the eggs hatch, the larvae are taken up into the mouth and carried, FishBase recording exactly this sequence for the congener Bujurquina syspilus ('eggs are deposited on leaves and guarded by both parents; larvae are taken into the mouth'). Carrying the spawning surface, and later the larvae, lets a threatened pair physically relocate the entire brood — a flexible defence well suited to shallow, predator-rich forest streams. Clutch sizes have not been reported for omagua; congeneric Bujurquina are modest-fecundity fish, with keepers of species such as Bujurquina oenolaemus reporting broods on the order of a couple of hundred fry raised by an attentive pair, a figure offered here only as a genus-typical guide. Parental care is biparental and extended: both adults shepherd the free-swimming young, taking them back into the mouth when alarmed, until the fry are large enough to forage independently.
In the aquarium
Bujurquina omagua is not established in the hobby. As of 2026 it has not been exported commercially, and no published keeper accounts exist. What follows is honest inference from the genus and from the species' documented biology; it is labelled as such throughout and should not be read as proven husbandry.
A pair of adult omagua, which top out at roughly 3.5–4 in standard length, can technically be kept in an aquarium of around 25 US gal, but a tank of 30–40 US gal gives a breeding pair enough room to establish a territory without constant conflict. Base the aquascape on fine or medium sand — the species lives over deep mud and leaf litter in the wild — with a layer of dried botanical leaves (Indian almond, oak, or similar) covering much of the bottom. Leaves serve two purposes: they recreate the species' natural floor and, critically, a clean broad leaf becomes the spawning surface the pair will select. Driftwood roots and branches provide visual breaks and additional shelter, and subdued lighting suits the dark, tannin-stained water the fish comes from. Dense planting is not required and may crowd the territory, but marginal stems and floating plants help diffuse light and buffer chemistry.
Water chemistry should match the soft, warm, slightly acid conditions of the Napo–Amazon terra-firme headwaters. Aim for 75–82 °F, pH 5.5–7.0, and low conductivity (below roughly 100 µS/cm); the target is clean, well-oxygenated water that sits comfortably in the soft-neutral range rather than hard or alkaline conditions. Dissolved oxygen matters: these are stream-adapted fish. Weekly water changes of 25–30% with RO or rain water mixed to the appropriate hardness are more important than chasing an exact pH figure. Hard, alkaline tap water is the most common keeper mistake with western-Amazonian cichlids; it suppresses condition, inhibits spawning, and may affect embryo development.
Bujurquina are peaceable outside a breeding territory by cichlid standards, and omagua is expected to follow that pattern. Suitable tankmates are other small, non-aggressive species from broadly similar western-Amazonian soft-water habitats — small tetras (such as Hyphessobrycon or Moenkhausia species), pencilfish, Apistogramma or other dwarf cichlids kept away from the Bujurquina's immediate territory, and small Corydoras on the sand. Avoid robust, fast-moving dithers that will outcompete the cichlids at feeding time, and do not house them with similarly sized or larger cichlids that will not respect the spawning territory. During breeding the pair becomes noticeably bolder in defence and will harass tankmates that wander close; a sufficiently large and broken-up tank minimises this.
Spawning, when it occurs, follows the genus pattern: the pair cleans a leaf (or occasionally another flat, movable surface), deposits a modest clutch in neat rows, and guards the eggs together. Once the eggs hatch, the larvae are taken into the mouth — primarily by the female at first, with both parents involved as the fry develop — and the pair can physically carry or nudge the leaf to a safer location if disturbed, the defining adaptation of the 'leaf mouthbrooder' mode. Expect a brood in the general range of a hundred to a couple of hundred fry based on congeners; omagua has not itself been bred in captivity and no clutch count has been published. Common mistakes at this stage are over-bright lighting, which makes the pair feel exposed and leads to egg-eating, and filtration that creates enough flow to scatter larvae. Sponge filtration is the practical choice: it provides biological filtration without a current or an intake that will trap fry. Overall difficulty is moderate — not a fish for a community tank with hard water, but not technically demanding for a keeper who understands soft-water Amazonian cichlids.
Conservation
Bujurquina omagua has not been evaluated by the IUCN Red List (Not Evaluated as of Red List version 2025-2, per FishBase), and it carries no CITES or CMS listing — unsurprising for a fish described only in 2023. That absence of a formal assessment is not the same as security. On present knowledge the species is a microendemic, recorded only from two small creek systems on a single terra-firme 'island' beside the Napo–Amazon confluence; its describers note that the distribution limits of essentially no lowland Bujurquina are known, so its true range could be somewhat larger or genuinely tiny. Either way, a fish restricted to shallow blackwater headwater streams in the Peruvian Amazon is exposed to the broad pressures reshaping the region — deforestation and road-building around Iquitos, sedimentation and pollution of small drainages, and the gold-mining and land-use change documented across western Amazonia — even though none of these has been shown to threaten this particular cichlid. It is not known to be in the aquarium trade. The responsible reading is that omagua is a newly described, narrowly distributed endemic of unassessed status whose conservation needs simply have not yet been studied.