Taxonomy & naming
Bujurquina megalospilus was described by the Swedish ichthyologist Sven O. Kullander in 1986, in his monograph 'Cichlid Fishes of the Amazon River Drainage of Peru' — the same 394-page work in which he erected the genus Bujurquina itself to hold a group of small, delayed-mouthbrooding acaras that had previously been lumped into the catch-all genus Aequidens. It was an original combination, valid from the outset, and it has stayed valid: the Catalog of Fishes, FishBase, GBIF and the IUCN all list it as Bujurquina megalospilus Kullander, 1986 with no junior synonyms, and the nomenclatural act is registered in ZooBank (73B6CC90-62CD-4B5B-889C-2D290C11BB19). The type locality is a pool near the Río Pachitea, about one kilometre above (north of) Tournavista, in Peru's Amazonian lowlands; the type material is held in the fish collection of the Swedish Museum of Natural History (NRM) in Stockholm, where Kullander worked. Within the family Cichlidae it sits in the subfamily Cichlinae (Cichlasomatinae of older usage) and the tribe Cichlasomatini, the South American 'true acara' lineage. Bujurquina is a species-rich genus — roughly eighteen valid species at last count, most of them in the western Amazon — and the members are notoriously hard to tell apart, so much so that Paul Loiselle published an annotated identification key in the Buntbarsche Bulletin (No. 140, 1990) specifically to help aquarists sort the Peruvian imports. In that key, Bujurquina megalospilus runs out at the very end of the thin-lipped branch, separated from its closest congeners by its outsized flank spots.
Morphology
This is a small cichlid: the maximum recorded length is 3 in standard length (snout to tail base), reported by Kullander from the type series, so a fully grown adult is roughly the size of a person's thumb. The body plan is the generic Bujurquina template — a moderately deep, laterally compressed acara with a large eye, a steep forehead and thin lips. What names the fish, and what makes it identifiable in life, is its colour pattern: the row of dark midlateral blotches typical of the genus is here exaggerated, with the spots 'greatly enlarged' and the second blotch in the series swollen into the single dominant marking on the flank, as Loiselle's key puts it. This is exactly what the epithet describes (Greek megas, large, plus spilos, spot). A dark midlateral band and a spot on the caudal peduncle complete the pattern, and the dorsal-fin lappets are dark with a narrow light submarginal stripe — a combination that, together with the thin lips and the absence of a strong predorsal nape mark, runs the fish to Bujurquina megalospilus rather than to the superficially similar Bujurquina hophrys, Bujurquina ortegai or Bujurquina apoparuana that share its range. As in most acaras the sexes are not strongly marked apart; sexual dimorphism in the genus is subtle, males averaging slightly larger and a touch more pointed in the unpaired fins, but Bujurquina megalospilus shows no dramatic, easily diagnosed difference between male and female, and ripe females are recognized mainly by their fuller body in the run-up to spawning. No published in-life colour photographs were catalogued by Kullander, and reliably identified images remain scarce, which is part of why the species is so seldom recognized in the trade.
Habitat
Bujurquina megalospilus is a Peruvian endemic of the upper Amazon basin, known from the Pachitea and Aguaytía river drainages on the eastern flank of the Andes. Its overall range is small for an Amazonian fish — the IUCN puts the extent of occurrence at about 26,000 square kilometres — and it occurs at moderate altitudes, between roughly 185 and 700 metres above sea level, higher and cooler than the true lowland floodplain. These are piedmont waters: the IUCN assessment describes the species as living in clear water, and its congeners in the genus are characteristically fish of small, slow, clear-water forest streams running down off the slopes, shaded and floored with leaf litter. No in-situ water chemistry has been published specifically for Bujurquina megalospilus, so the figures in the fact box are flagged as habitat- and genus-typical rather than measured for this species: warm, soft, slightly acidic to near-neutral clear water (around 75–82 °F, pH roughly 6.0–7.5) in shallow streams a metre or two deep, the conditions documented for clear-water western-Amazon piedmont creeks and for the better-studied Bujurquina such as Bujurquina syspilus and Bujurquina zamorensis. Treat them as defensible context for the biotope, not as direct readings.
Feeding
Wild feeding has not been studied in detail for Bujurquina megalospilus, but the IUCN assessment characterizes it as omnivorous with a tendency toward insectivory — a fish that takes mostly small invertebrates while not refusing plant and detrital material. That fits its body plan and its habitat: a small, large-eyed, diurnal acara working the litter and margins of a shaded forest creek is well placed to pick aquatic insect larvae, small crustaceans and terrestrial invertebrates that fall onto the water, supplemented by fallen fruit and detritus when the insect supply thins. FishBase's modelled trophic level of about 3.4, derived from body size and the diets of close relatives rather than from gut contents, is consistent with that mostly-carnivorous-but-flexible reading. In its community it is a small mid-level forager rather than a top predator, and its low fishing-vulnerability score reflects a fish of little interest to anyone but the occasional subsistence netter.
Mating
Detailed courtship has not been documented for Bujurquina megalospilus itself, but the reproductive biology of Bujurquina is well established and highly conserved across the genus, so the picture is reliable in outline. These are monogamous, biparental acaras that form a pair and jointly defend a territory and brood — the male and female sharing guard duty rather than the female-only or harem systems seen in some other Neotropical cichlids. The IUCN notes that reproduction in this species is aseasonal (it can spawn year-round rather than being tied to a flood pulse) and that the fish provide parental care. Pair formation in the genus follows the usual acara pattern of mutual display, lateral spreading of the fins and substrate cleaning before a movable spawning surface is chosen. Bujurquina are not heavily armoured brawlers; territorial defence is real but scaled to a small fish, and keepers of related species describe pairs holding a nest fearlessly even against much larger tankmates.
Breeding
The defining trait of Bujurquina — and the reason the genus is worth singling out — is that its members are biparental delayed, or 'larvophile,' mouthbrooders. Unlike the maternal mouthbrooders of the African rift lakes, which take the eggs into the mouth at spawning, a Bujurquina pair first lays its eggs in the open, the way a substrate-spawning cichlid would, and only takes the brood into the mouth later. The eggs are deposited not on a fixed rock but on a movable object — a leaf, a flat stone, a thin piece of slate, even a loose plastic plant in aquaria — which the parents can pick up and shift to keep the clutch out of harm's way; when danger threatens, or when the larvae hatch, the eggs or wrigglers are gathered into the mouth and carried. Both parents share the brooding, passing the larvae back and forth, a behaviour the same as that of the closely allied 'Inca stone cichlid' Tahuantinsuyoa. Spawn-specific figures for Bujurquina megalospilus have not been published; clutches in the genus are modest, on the order of a few dozen to a couple of hundred small eggs, and the eggs are notably tiny, so the fry are small at first feeding. A hobbyist account of the related Bujurquina zamorensis (MonsterFishKeepers community thread, 2015, labelled here as anecdote) captures the behaviour well: a four-inch pair laid on the dislodged base of a plastic plant and were repeatedly photographed dragging the egg-bearing object around the tank, guarding it in the open even among far larger severums. For Bujurquina megalospilus the same delayed-mouthbrooding strategy can be taken as the working assumption.
In the aquarium
Bujurquina megalospilus is rarely offered in the trade and even more rarely identified by name — imports of western-Amazon 'acara' that include it usually arrive unlabelled, mixed with Bujurquina syspilus or other look-alikes. That said, its husbandry falls squarely within the Bujurquina template, and keepers familiar with the genus report the group to be manageable and rewarding, particularly for anyone willing to set up a biotope-style western-Amazon stream tank. The figures and strategies below are based on the genus and on habitat data; where the species is thin in the literature that is acknowledged.
A tank of around 20–25 US gal (roughly 90 × 15.5 in footprint) is adequate for a pair, though 30 US gal gives more flexibility when a guarded territory is established. Because the fish is small (under eight centimetres) it does not need the space a pair of severums or eartheaters requires, but it is assertive during breeding and needs enough room that a subordinate fish — or a tankmate caught in the wrong place — can retreat out of sight. Water should replicate the soft, warm, near-neutral chemistry of its piedmont home: aim for 75–82 °F, pH 6.0–7.2 and low to moderate hardness (general hardness no higher than about 8 °dH, softer is better). Good filtration with a gentle current is more important than perfectly soft water; the fish tolerates slightly harder conditions in practice, but egg fertility and fry survival improve markedly when hardness is kept low.
The substrate should be fine sand — not gravel — with a layer of dried leaf litter (Indian almond or oak leaves work well) that will break down slowly and acidify the water gently. Smooth driftwood pieces and twisted roots provide refuge and break up sightlines. The key decor element for this species is a ready supply of broad, light, movable leaves: the pair need something they can physically shift when they spawn. A dead Indian almond leaf with its stem intact, a thin piece of cork bark, or even a flat, smooth tile placed loosely on the sand will be auditioned. Java fern and Echinodorus species are appropriate plants for the western-Amazon context; floating plants (Amazon frogbit, for instance) dim the light, which relaxes the fish. Bright open tanks with no refugia make Bujurquina nervous and prone to hiding.
For tankmates, Bujurquina megalospilus is peaceful outside of the immediate spawning territory. In a species-only or near-species-only setup it is best kept as a pair; in a community it does well with small, similarly soft-water fish — pencilfish (Nannostomus), hatchetfish, small tetras such as Hyphessobrycon species, and small Corydoras or Otocinclus on the bottom. Avoid any cichlid large enough to bully it, and avoid genuinely aggressive dwarfs such as Mikrogeophagus ramirezi during a spawning bout, when the Bujurquina will be bold and persistent in defending their leaf. Curimatids or small loaches that root through the leaf litter are usually ignored. Do not combine with any fish large enough to trigger a fear response, as stressed Bujurquina tend to abandon eggs.
Breeding follows the biparental delayed-mouthbrooding pattern documented across the genus. The pair clean and defend a chosen leaf — or whatever substitute the keeper has provided — and lay a clutch of small eggs on its surface, typically numbering in the dozens to low hundreds. Both parents fan and guard the eggs; within a day or two of hatching, the wrigglers are gathered into the mouth and brooded, with male and female sharing the brood, passing the larvae between them. Keepers of related species (notably Bujurquina zamorensis) note that the parents continue to carry and spit out the mobile fry for several days, and that the eggs on the leaf are often transported to a new site before hatching — the fish literally picks up the leaf and carries or nudges it. First foods for the fry are micro-organisms on leaf detritus, then newly hatched brine shrimp and microworms once they are free-swimming. The most common keeper mistake is removing the parents too soon or destabilising the tank (sudden water changes, bright lights, opening the lid frequently) during the critical guarding period, which causes egg abandonment. A second common mistake is housing the pair with boisterous tankmates that regularly approach the nest; this produces the same result. Given calm conditions and soft water, pairs in the genus spawn readily and repeatedly.
Conservation
The IUCN Red List assesses Bujurquina megalospilus as Least Concern (assessed 21 April 2014 by M. Hidalgo del Aguila, published 2016). The reasoning is that the species has a relatively wide range within its basins, is common and abundant where it occurs, and shows a stable population overall, even though some subpopulations are under local pressure. It carries no CITES listing and is of no commercial fishery value, used at most as a local subsistence protein source. The threats the assessment does flag are pointedly local and modern: on the Río Neshuya, untreated effluent from palm-oil plantations is degrading water quality (driving anoxia and organic loading), alongside industrial and urban wastewater in a small river with little capacity to dilute it; on the Río Pachitea, land conversion for cattle ranching is causing erosion and reducing the insect and fruit supply the fish depends on, and water is further contaminated by the runoff of illegal coca-to-cocaine processing. The species' saving grace is partly geographic: its westernmost populations lie in the buffer zones of Parque Nacional Cordillera Azul and the Reserva Comunal El Sira, which afford some protection even though the fish is not confirmed to occur inside a strictly protected area. As a narrow-range, clear-water piedmont endemic rather than a wide-ranging floodplain generalist, Bujurquina megalospilus is exactly the kind of small Amazonian cichlid whose long-term status depends on the catchment-level health of a handful of Andean-foothill rivers — so while the global listing is genuinely Least Concern, the local water-quality pressures the assessors named are the ones worth watching.