Taxonomy & naming
The Swedish ichthyologist Sven O. Kullander described Apistogramma alacrina in 2004, in Ichthyological Exploration of Freshwaters (15(1):41-48). It sits in the cichlid subfamily Cichlinae, tribe Geophagini — the South American "eartheaters" and their dwarf relatives — within the large, taxonomically thorny genus Apistogramma. The genus name blends the Greek apisto (uncertain) and gramma (a graphic mark or line), a fitting label for a group whose species boundaries have given taxonomists fits for decades.
The epithet alacrina is a piece of anatomical wordplay, not a reference to liveliness. Kullander coined it from the Latin ala (or axilla), 'armpit', joined with crinis, 'hair', for the dark lining at the base of the pectoral fin, which to his eye resembled dark hair sprouting from an armpit. The Catalog of Fishes, FishBase and the ETYFish Project all give this same reading, so the meaning — though it sounds like the Latin alacer, 'lively' — is securely descriptive and anatomical.
The holotype (UF 33670) and its paratypes came from a roadside pond in the Río Ariari, part of the Río Guaviare drainage in the Department of Meta, Colombia — squarely in the Orinoco basin, on the road between Vista Hermosa and San Martín. Within the hobby's working framework, the species-groups system assembled by Mike Wise (apistogramma.com), Tom Christoffersen and Frank Hättich, the species anchors the "alacrina-group" inside the broader "regani-lineage," a lineage diagnosed by a complete set of four infraorbital and five dental head pores. That placement matters biogeographically: the regani-lineage is thought to have seeded both the alacrina- and macmasteri-groups as Apistogramma spread into the Orinoco system. As the aquarium strain Apistogramma sp. "Rotpunkt," the fish was a hobby animal for decades before it had a formal name, though its precise origin and date of introduction are unclear. Whether "Rotpunkt" is strictly conspecific with the described Apistogramma alacrina has never been fully settled, and experienced keepers — Christoffersen among them — have gone further, suggesting the original description may have lumped two or three distinct forms together.
Morphology
This is a true dwarf cichlid: FishBase lists a maximum of about 2.2 in (2 in) standard length, and most aquarium specimens are smaller still. The body is short and fairly deep, with the elongate dorsal fin (16-17 spines and 7-8 soft rays) typical of the genus; the anal fin carries three spines, and vertebrae number 24-26. The most reliable field mark — the one Kullander used to separate it from every other Apistogramma — is the pectoral region: a prominent dark blotch wraps the ventral (lower) base of the pectoral fin, kept distinctly separate from a smaller dark spot at the dorsal (upper) base.
Like most dwarf cichlids, the species is strongly sexually dimorphic. Males are the larger, gaudier sex, developing the reddish spotting on the flanks and finnage that earned the trade name "redspotted dwarf cichlid." Females run smaller and plainer outside of breeding, then turn an intense yellow when guarding eggs. One feature is worth flagging because keepers disagree on it: females from the Río Orteguaza population (Caquetá, on the Amazon side) — the source of some of Kullander's paratypes — often show a broad black blotch on the anal fin, yet other wild females from the same catches lack it entirely. That inconsistency is part of why the species' identity stays unsettled, since coloration that should diagnose a population does not behave consistently.
Habitat
Apistogramma alacrina is a Colombian endemic with an unusual cross-basin distribution. The Catalog of Fishes and FishBase place it in both the Amazon drainage — the Río Orteguaza and neighboring waters of Caquetá and Putumayo — and the Orinoco drainage, in the upper Guaviare and Meta systems where the type material was collected. That puts the species on both sides of one of South America's great drainage divides, a pattern that reflects the shared geological history of the lowland llanos and the Amazonian piedmont rather than any modern connection. Authoritative sources confine the documented range to Colombia; reports from neighboring Peru are not supported by FishBase or the Catalog of Fishes and are best treated as unconfirmed.
Its waters are the soft, acidic, mineral-poor streams and ponds characteristic of the region. Keepers collecting and importing the Putumayo and Orteguaza forms report in-situ readings of roughly pH 4.5-6 with very low dissolved-mineral content — classic tea-stained, leaf-littered habitat where dwarf cichlids shelter among submerged roots and drifted litter on the bottom. The type series itself came from a roadside pond, a reminder that this is a fish of small, often still or sluggish backwaters as much as flowing streams. As a benthopelagic fish it lives close to that substrate rather than in open water. This is not a rift-lake species and shouldn't be read as one: it belongs to the flowing and still freshwaters of the western Amazon-Orinoco lowlands, not a single defined lake.
Feeding
Specific gut-content studies of Apistogramma alacrina are lacking, so its ecology has to be inferred from the genus and from the habitat it occupies. FishBase places it at a trophic level of about 3.4 — the omnivore-with-a-carnivorous-bent band typical of Apistogramma. In practice these dwarf cichlids work the leaf litter and soft substrate of their streams, taking small invertebrates: insect larvae, microcrustaceans, worms and other meiofauna sifted or picked from detritus. Like its eartheater relatives in the Geophagini, it forages along the bottom rather than hunting in midwater, and it will take a bite of substrate to work the edible fraction out of it.
In the community it fills the small-predator niche at the base of the food web, eating tiny animals and in turn serving as prey for larger fish, wading birds and other stream predators. Its medium resilience and low fishing-vulnerability scores in FishBase describe a small, fast-maturing fish with a short generation time — the profile of an abundant but localized species rather than a slow-growing apex one. In the aquarium the same diet translates straightforwardly into small live and frozen foods — baby brine shrimp, microworm, daphnia, cyclops and finely chopped bloodworm — which it hunts along the bottom.
Mating
By the temperament standard of dwarf cichlids, Apistogramma alacrina is mild-mannered. Keepers who have maintained the wild Putumayo and Orteguaza forms describe them as calm, peaceful fish that hold together even in groups. Tom Christoffersen kept a colony in roughly 40-gallon (160-liter) tanks and reported them spawning without the group dissolving into war — not something you can say of every Apistogramma — and one pair in his group bred more or less continuously.
Many Apistogramma run a harem system in which one dominant male holds and patrols the overlapping territories of several females, and the alacrina-group is generally described that way. The picture for this species is muddier: at least one experienced keeper watched his males behave with no polygamy at all, defending single pairs rather than harems. However the bond is structured, courtship is bound up with the spawning cavity and with the female's color change. As she ripens she turns brilliant yellow, claims a small cave and grows sharply more aggressive, while the male's role shifts toward holding and defending the wider territory around her. Spawning is triggered the way it is across the genus — by soft, warm, acidic water and the availability of suitable caves — and is reported to be straightforward, on par with the rest of the alacrina-group. The practical requirement for a keeper is plenty of small, dark cavities — caves, coconut huts, half-buried shells — so females can space themselves out and the social system, whatever its exact shape in a given group, has room to settle.
Breeding
Reproductively the species follows the genus playbook: it is a substrate-spawning cave brooder with female-dominated brood care. A female stakes out a small cavity — a hollow under wood, a cave, a half-buried shell — cleans it, and lays a clutch on its ceiling or wall, which the male then fertilizes. From that point she does the close work largely on her own, tending and fanning the eggs inside the cave while the male patrols the wider territory and drives off intruders. As the eggs hatch and the wrigglers absorb their yolk, she leads the free-swimming fry out of the cave in a tight, guarded shoal, herding them across the substrate and snapping them back toward cover at any disturbance — the brilliant yellow guarding dress doubling as a signal to her own fry and a warning to rivals.
Clutch sizes have not been formally documented for wild Apistogramma alacrina, but they fall in the modest range usual for small Apistogramma — on the order of a few dozen to perhaps a hundred-plus eggs depending on female size. Spawning is reported as undemanding once the water is right; in aquaria the limiting factor is chemistry rather than any reluctance to breed. As with most dwarf cichlids, fry are tiny and need infusoria-grade first foods before graduating to newly hatched brine shrimp. Where conditions hold steady a pair will spawn repeatedly, which is exactly how the continuously breeding colony noted by keepers maintained itself.
In the aquarium
Apistogramma alacrina is undemanding in behaviour, but its soft, acidic water is non-negotiable, and that chemistry is where nearly every failure happens.
Tank: A pair does well on a base footprint of 45 × 12 in or larger; a colony or a male-with-several-females group needs considerably more room. Tom Christoffersen kept stable breeding groups in 160-litre tanks (100 × 40 × 15.5 in) that stayed peaceful even during spawning — a useful marker both for minimum group sizing and for how well this species tolerates its own kind when space allows.
Aquascape: Recreate the shallow, leaf-littered backwaters it comes from — soft sand, tangles of wood and roots arranged into shady overhangs, and a good supply of small caves (ceramic flowerpots on their sides, coconut-husk huts, half-buried hollow logs). Dried beech, oak or Catappa (Indian almond) leaves over the sand finish the look and earn their keep: as they break down they release tannins that mildly acidify the water, feed the microbial films fry graze on, and add cover. Replace the leaves every few weeks or let them decay fully. Floating or low-light plants (Anubias, Microsorum, Cryptocoryne) shade the tank; bright light stresses a fish from tea-stained forest streams.
Filtration and water changes: Keep flow gentle — around four to five times the tank volume per hour, often a sponge filter running alongside an external one. This is not a fish for strong current or a sterile display. Water changes should be small and frequent, 10–15% weekly. Large changes are a common and serious mistake: they swing the chemistry hard enough to stress adults and can crash a brood of fry, which are highly sensitive to sudden shifts in pH and mineral content.
Water: Mirror the wild source — pH 5.0–6.5 is a practical keeper target (wild fish are collected at pH 4.5–6), soft to very soft (the in-situ reports describe mineral content as simply 'low'), and 75–84 °F. The fish will often tolerate somewhat harder, higher-pH water for routine maintenance, but conditioning, spawning and fry-rearing all go best at the soft, acidic end. Where tap water is hard or alkaline, lightly remineralized reverse-osmosis water — or RO blended down with hard tap water to hit the target hardness — is the standard fix.
Food: Offer a varied rotation of small live and frozen invertebrates — newly hatched brine shrimp (Artemia nauplii), daphnia, cyclops, microworm and finely chopped bloodworm (chironomid larvae). Most specimens learn to take good small pellets or granules as a staple, but live and frozen foods are essential for conditioning breeders. Feed small meals several times a day rather than one large feeding, which matters especially when fry are present.
Tankmates: Choose small, peaceful upper-water fish that act as dither — pencilfish (Nannostomus spp.) are the classic recommendation, along with small characins from similarly soft water. Avoid other Apistogramma species in the same tank; even placid species can hybridise, and territorial interference during spawning is a common source of failed broods. Bottom-dwellers such as loricariids and Corydoras should be chosen with care and are often left out of a breeding setup, since they intrude on ground the female treats as her own.
Difficulty is moderate. The behavioral side — feeding, social dynamics, willingness to breed — is straightforward and forgiving; the chemistry is not, and it is where most keepers who struggle with this fish go wrong, keeping water too hard, too high in pH, or performing large water changes at the wrong time. Get the water right and Apistogramma alacrina breeds readily and, given adequate space, can be kept and observed as a colony.
Conservation
The IUCN Red List assesses Apistogramma alacrina as Near Threatened (Lina Mesa-Salazar; assessed 5 August 2020, published 2020), under criteria B1b(iii)+2b(iii) — criteria that flag a restricted and declining range rather than outright collapse. Note a common source conflict: the Cichlid Room Companion's older species page still records the fish as 'not evaluated,' a snapshot that predates the 2020 assessment, while FishBase carries the current Near Threatened listing. The B-criteria basis points to the real pressure: this is a Colombian range-restricted lowland fish whose habitat quality is in decline, not a fish being taken to commercial exhaustion — FishBase rates its fishing vulnerability as low (10 of 100). There is an ornamental-trade dimension, since wild Apistogramma cf. alacrina are collected and exported for the aquarium hobby, but for a small, fast-breeding dwarf cichlid the heavier hand is habitat change.
Placed in its wider setting, this is a western Amazon and Orinoco lowland species rather than a lake endemic, so the relevant context is the condition of those clearwater and blackwater stream systems — the soft, acidic, leaf-littered waters of the Colombian llanos and Amazonian piedmont. Across Neotropical freshwaters the documented pressures are deforestation, agricultural conversion, sedimentation and shifting hydrology, all of which degrade exactly the low-mineral, structurally complex habitats this fish depends on; the regional diversity itself is catalogued in the standard checklists of the South American ichthyofauna (Kullander's Cichlidae treatment in the Check List of the Freshwater Fishes of South and Central America). The honest read is the cautious one the assessment supports: Apistogramma alacrina is not in crisis, but its Near Threatened status is a flag that a narrow-range, soft-water specialist has little margin if the streams it occupies keep degrading.