Taxonomy & naming
Copeina guttata was originally described as Pyrrhulina guttata by the Austrian ichthyologist Franz Steindachner in 1876, with type localities in the Brazilian Amazon — including Óbidos, Cudajas (Cudaias), and Tabatinga, as well as the Rio Negro. Edward Drinker Cope described a synonym, Pyrrhulina argyrops, in 1878. The species was later transferred to the genus Copeina, where it remains as the valid name Copeina guttata (Steindachner, 1876) per Eschmeyer's Catalog of Fishes. The parenthetical authority reflects the change of genus from the original description.
Copeina belongs to the family Lebiasinidae, a group of small neotropical characoids that share a distinctive body plan suited to life near the water surface. Within Lebiasinidae, Copeina is the sister group to Pyrrhulina — the genus in which this species was originally placed — and the two genera share the habit of surface feeding and, in Copeina, the notable departure into male parental care. The genus name honours the American zoologist Edward Drinker Cope, a prolific describer of South American fishes.
Morphology
Copeina guttata is an elongate, moderately compressed characin with a slightly upturned mouth that betrays its preference for feeding at or near the water surface. FishBase records a maximum standard length of 3 in; Seriously Fish gives 3 in SL, consistent with that figure. The body is streamlined and the dorsal profile fairly straight, in keeping with a fish that spends much of its time in the upper water column.
The flanks are pale to golden-buff, overlaid with rows of reddish to orange-red spots — the 'guttata' (spotted) of the specific name — that run along the sides and give the fish its common names. Males develop more intense coloration than females and, in breeding condition, display heightened red on the fins. The species is sexually dimorphic: males tend to be slightly more robust once in full colour, and breeding males deepen noticeably in hue. The fins are relatively large and rounded, useful for the fanning behaviour the male performs over eggs.
Habitat
Copeina guttata inhabits the middle Amazon basin, including the Solimões (upper Amazon) and its tributaries, with confirmed records from Brazil, Peru, Ecuador, and Colombia. Type localities span Brazilian Amazon stations from Óbidos on the lower-middle Amazon to Tabatinga on the Colombian border, and the Rio Negro.
The species is a freshwater pelagic fish of the upper water column in slow-moving to still waters, typical of floodplain systems, marginal vegetation zones, and quieter tributaries. FishBase records a temperature range of 73–82 °F; Seriously Fish extends this to 68–82 °F, reflecting the range of habitats and seasons across the broad Amazon basin. pH tolerance is wide — Seriously Fish notes 4.0–7.5, consistent with Amazonian blackwater and whitewater systems — with hardness up to around 18 dH. The species is notably intolerant of deteriorating water quality and high dissolved organic loads.
Feeding
Copeina guttata is a predatory surface feeder in the wild, oriented toward insects and other invertebrates at or near the water surface. The natural diet includes terrestrial insects, aquatic insect larvae, worms, and small crustaceans — foods that drift onto or emerge from the water's surface in the seasonally flooded Amazonian habitats the species frequents.
In the aquarium the species thrives on a diet of small live and frozen foods: bloodworm, Daphnia, brine shrimp, and other zooplankton. It will accept high-quality flake and small pellets but shows clear preference for foods that can be taken at the surface or in the upper water column. A diet weighted toward live or frozen invertebrates improves colour, condition, and willingness to breed. Feeding near the surface suits the species' upward-angled mouth and natural foraging posture.
Mating
Copeina guttata departs sharply from the scatter-spawning norm of most characins. Breeding is initiated by the male, who excavates a shallow depression in the substrate — a sand pit nest — and then courts a female with displays intended to draw her to the nest. The courtship involves lateral displays and fin-spreading to show off coloration, with males in full breeding condition flushing a deeper red-orange.
When a receptive female enters the pit, spawning takes place in the depression, with eggs deposited directly onto the substrate or into the shallow excavation rather than scattered freely among plants. The process produces an adhesive clutch in a defined site — a fundamentally different reproductive strategy from the open-water egg-scattering seen in most of the family, and one that sets the stage for the male's subsequent parental role.
Breeding
After spawning, the female takes no further part in reproduction. The male remains with the nest, guarding the eggs against disturbance and fanning them with his fins to maintain water circulation and oxygenation — a behaviour rarely seen in characins. FishBase notes that the eggs hatch in approximately 24 hours, after which the male continues to tend the fry, fanning and guarding them until they become free-swimming.
In the aquarium, breeding Copeina guttata requires a tank with a fine, sandy substrate to allow pit excavation, good water quality, and a diet of live or frozen foods to bring fish into breeding condition. The male can become aggressive toward the female after spawning, so provision of adequate space or separation of the female post-spawn is advisable. AquaticRepublic notes that captive breeding records for this species are sparse, suggesting it is less frequently bred in captivity than other lebiasinids, despite the relatively accessible care requirements. Successful breeding depends on clean, well-oxygenated water — the species' well-documented intolerance of organic buildup is particularly relevant at the fry stage.
In the aquarium
Copeina guttata is best kept in a quiet, well-filtered aquarium with a fine sand substrate that accommodates the male's nesting excavation. A tank of 31.5 in or more in length gives males adequate territory and allows females a refuge from courtship pressure. The species does best in soft, slightly acidic to neutral water (pH 4.0–7.5) at 73–82 °F, consistent with its broad Amazonian range. Seriously Fish emphasises that the species is intolerant of elevated organic waste, making efficient filtration and regular water changes non-negotiable.
Because Copeina guttata is a surface-oriented fish with a strong jump reflex — a trait common to lebiasinids — a tight-fitting lid is essential. It is peaceful toward dissimilar tank mates but may nip the fins of slow-moving or long-finned species, and males can be territorial with one another, particularly when a male is guarding a nest. Small to medium Amazonian companions of similar water requirements — pencilfish, smaller tetras, small corydoras — make suitable tank mates. A well-planted tank with floating cover and shaded areas is appreciated and will encourage the natural surface-patrol behaviour. Colour shows best in indirect lighting with dark substrate.
Conservation
Copeina guttata has no independently published IUCN Red List assessment. FishBase records the species as Least Concern based on its 2025 database update, and AquaticRepublic references a 2020 assessment year with an LC inference; however, no dedicated IUCN species page was located for this species at the time this article was compiled, so the status should be treated as an informal LC inference rather than a formally published assessment.
The species occupies a wide swath of the middle Amazon basin across Brazil, Peru, Ecuador, and Colombia — a large and still broadly intact hydrological system — and is unlikely to face acute range-wide threat in the near term. Localised pressures such as habitat degradation in floodplain zones, deforestation affecting riparian buffers, and mercury contamination from artisanal gold mining affect many Amazonian fish communities, including this species' range. Collection for the ornamental trade occurs but is not thought to threaten the population at basin scale. A formal IUCN assessment would give clearer guidance on any localised declines.