Taxonomy & naming
Andinoacara blombergi was described in 2012 by Nicklas Wijkmark, Sven O. Kullander and Ramiro E. Barriga Salazar, in the same Ichthyological Exploration of Freshwaters paper (23(2):117–137) that redescribed Andinoacara rivulatus and sorted out the tangle of names attached to the 'green terror.' That description was part of a long effort to show the hobby name covers at least three distinct fish: Andinoacara rivulatus sensu stricto of the Guayas and neighbouring drainages, the Peruvian Andinoacara stalsbergi, and this northern Ecuadorian Esmeraldas-basin species. The genus Andinoacara was erected in 2009 by Zuzana Musilová, Oldřich Říčan and Jan Novák for a clade of trans- and cis-Andean cichlids; the name fuses andino- (the Andes, across whose slopes the genus is distributed) with acará, the Tupí-Guaraní word for cichlids. The species sits in the rivulatus group and in subfamily Cichlinae (the Cichlasomatini of older usage). Its holotype is held at the Escuela Politécnica Nacional in Quito (MEPN), and the type locality is the Río Toachi about 11 mi downstream of Alluriquín, in the Río Esmeraldas drainage of Pichincha province. FishBase and the Catalog of Fishes give the range as the Río Esmeraldas drainage, possibly extending into the adjacent Río Santiago of northern Ecuador. The epithet honours Rolf Blomberg (1912–1996), the Swedish explorer, writer, photographer and filmmaker who made several expeditions to Ecuador and eventually settled in Quito.
Morphology
Andinoacara blombergi is a robust, deep-bodied, laterally compressed cichlid with the steep forehead and large head typical of its group. FishBase gives a maximum of 4 in standard length, the largest examined specimen weighing about 49 g — though, as with its relatives, well-grown aquarium males would be expected to exceed the size of preserved wild material. It is very close to Andinoacara rivulatus and Andinoacara stalsbergi, sharing with them 8–12 (usually 9–10) relatively small predorsal scales, and is separated chiefly on counts and proportions. Wijkmark and colleagues diagnosed it by 25 scales in the E1 lateral scale row (versus 24 in Andinoacara rivulatus), together with a comparatively narrow head at about 15–18 percent of standard length, and distinctive male-versus-female coloration. The body shows the metallic green-to-blue-green iridescence of the group, scales catching turquoise highlights, and the head carries the fine, wavy bluish cheek streaks that run through the whole rivulatus complex; the dorsal and caudal fins are margined. Sexual dimorphism follows the group pattern: males grow larger and longer-finned and develop a fleshy nuchal hump on the forehead with age and condition, while females stay smaller, rounder and shorter-finned. On a glance it is hard to separate from its congeners, and it is most reliably identified by drainage — the Esmeraldas basin — plus that higher E1 scale count.
Habitat
Andinoacara blombergi belongs to the Pacific (trans-Andean) slope of northwestern Ecuador, essentially restricted to the Río Esmeraldas drainage and possibly the adjacent Río Santiago. The type locality on the Río Toachi below Alluriquín lies on the western Andean foothills, so the species spans coastal lowland rivers and their premontane reaches — the same flowing, structured coastal-river habitat that its relative Andinoacara rivulatus occupies in the Guayas basin to the south. No detailed in-situ water-chemistry profile for blombergi has been widely published. By analogy with the closely related Andinoacara rivulatus, which lives in near-neutral to alkaline coastal waters, the pH and temperature values given here are read across from the group as habitat-typical estimates rather than measured field figures, and should be treated as such; likewise no formal depth band is recorded, and the range of about 0–10 ft simply reflects a fish of river channels and pools. The Esmeraldas basin is a wet, forested-to-agricultural coastal drainage, and blombergi can be expected to behave as the tolerant generalist its group is, persisting in worked landscapes as well as more intact reaches.
Feeding
No dedicated diet study has been published for Andinoacara blombergi, so its feeding ecology is inferred from its anatomy and its close relatives. FishBase estimates a trophic level of about 3.2, consistent with an omnivore that leans toward small animal prey. Like other Andinoacara of the rivulatus group it has the conical jaw teeth and generalist pharyngeal apparatus of a substrate-oriented forager, and can be expected to take aquatic insect larvae, small crustaceans, worms, other benthic invertebrates and assorted organic matter from the river bed, supplemented with plant material and detritus. In the river community it works as a medium-sized, benthic-leaning omnivore. As with its relatives, captive fish of this group are unfussy and readily take prepared, frozen and live foods — behaviour that fits an opportunistic wild diet.
Mating
Andinoacara blombergi is, like the rest of its group, a biparental pair-forming substrate spawner. Courtship has not been documented for this species specifically, but the rivulatus group is well observed in aquaria and the pattern is consistent: a male and female form a bond, jointly select and clean a spawning surface, and defend a territory around it together. These are far more assertive fish than the small Bujurquina — the group's best-known member, Andinoacara rivulatus, earned the trade name 'green terror' for exactly this reason — and a bonded blombergi pair can be expected to hold and defend its territory forcefully, especially around the nest. Courtship runs the usual cichlid repertoire of lateral displays, fin-spreading and joint substrate-cleaning, with the metallic body colour and marked fins serving as display signals. Pair compatibility matters here: an unbonded male can persecute a female, a behaviour well documented in captive Andinoacara rivulatus and expected in this species too.
Breeding
Andinoacara blombergi is an open, biparental substrate spawner — the standard reproductive mode of its group, and a sharp contrast to the leaf-carrying mouthbrooding of the more distantly related acaras. No spawning has been documented for blombergi specifically, so the account here draws on its close and well-studied relative Andinoacara rivulatus and the group as a whole. A bonded pair cleans a flat surface — a stone, a slab or cleared substrate — and the female lays a sheet of adhesive eggs on it, which both parents then tend: the female concentrating on fanning and direct egg-care, the male on perimeter defence. After hatching, the wrigglers are moved to pits and guarded, and once free-swimming the fry are herded and defended as a school by both parents, in the extended biparental care typical of the genus. Clutch size has not been reported for blombergi; the closely related Andinoacara rivulatus is a productive spawner laying several hundred eggs, and a comparable brood is a reasonable genus-typical expectation, offered here as a labelled estimate rather than a documented figure. Spawnings can recur at short intervals when a pair is in condition.
In the aquarium
Andinoacara blombergi is essentially unknown in the hobby under its own name. It was only split from the rivulatus complex in 2012, and Esmeraldas-basin fish sold as 'green terror' are not distinguished in the trade from true Andinoacara rivulatus, so dedicated keeper accounts are absent. Husbandry guidance therefore leans on its very close relative Andinoacara rivulatus — one of the most thoroughly kept cichlids in the hobby — with this species' own size data as the anchor.
Tank: for a fish that reaches at least 4 in standard length in wild material, and likely more in well-fed aquarium males (plausibly into the high teens of centimetres total length), a single specimen or a confirmed pair needs a substantial tank on the order of 65–105 US gal with a long footprint, both to satisfy a territorial cichlid and to carry the bioload of a heavy-bodied feeder. Use sand or fine-to-medium gravel, since these fish dig, especially in breeding condition; large stable rockwork and heavy driftwood divide territory and provide spawning sites, and a flat-topped rock or slab makes an ideal egg-laying surface. Robust, fast-growing or potted plants can survive, but loosely rooted plants will be rearranged.
Water: track the near-neutral to mildly alkaline, moderately hard coastal rivers of western Ecuador — comfortably around neutral to slightly alkaline pH and moderate hardness, at a warm tropical temperature in the mid-20s Celsius. Like its relatives it is hardy across a fairly broad range but does less well kept long-term in soft, strongly acidic water. Generous filtration and regular water changes matter for a large, strongly feeding cichlid.
Tankmates: treat blombergi as a robust, territorial 'green terror'-type fish, capable of intimidating and injuring rivals, with intraspecific aggression especially intense. Choose sturdy tankmates of comparable size that occupy different zones, and avoid small or timid species; many keepers of this group run such fish as a single specimen, a single bonded pair, or in a large species tank.
Common mistakes: the real demands are space and aggression management rather than any delicacy — it should be straightforward in group-appropriate conditions. Because Esmeraldas-basin fish are not distinguished in the trade, a keeper specifically wanting blombergi would need reliable provenance information tying the fish to that drainage.
Conservation
The IUCN Red List assesses Andinoacara blombergi as Least Concern (LC), assessed in October 2014. The species occupies the Río Esmeraldas drainage and possibly the adjacent Río Santiago — a reasonably extensive coastal basin rather than a pinpoint range — and, like its relatives, it is a tolerant generalist of coastal and premontane rivers rather than a narrow specialist, which buffers it against localised disturbance. It carries no CITES listing, and FishBase classes it as harmless and of low fishing vulnerability with high resilience. The familiar pressures on western-Ecuadorian Pacific-slope rivers still form the backdrop: the Esmeraldas basin is heavily worked for agriculture (including oil-palm and banana) and faces deforestation, mining, and pollution from agricultural and urban sources. None of these is documented as a population-level threat to blombergi specifically, and its Least Concern listing reflects a fish that is currently secure across a moderately wide coastal range, even if the broader health of its drainage is worth watching.