Taxonomy & naming
The species was described by Albert Günther in 1867 (with a fuller treatment in 1868) on the basis of material from the Río Motagua in Guatemala. Günther placed it in Heros, a catch-all genus of the period, and for most of the twentieth century it was carried under the vast assemblage Cichlasoma as Cichlasoma motaguense — the name under which generations of aquarists knew it.
The modern arrangement places it in Parachromis, the genus used for the Central American guapotes, alongside the better-known Parachromis managuensis (the jaguar cichlid), Parachromis dovii (the wolf cichlid), Parachromis friedrichsthalii and Parachromis loisellei. The transfer out of its original genus means the authority is written with parentheses: Parachromis motaguensis (Günther, 1867). Eschmeyer's Catalog of Fishes recognises the species as valid in Parachromis within the Cichlidae (Cichlinae, tribe Heroini). The species has at times been confused with its relatives in the trade, and the 'false yellowjacket' common name distinguishes it from the true yellowjacket cichlid, Parachromis friedrichsthalii.
Within Parachromis, motaguensis sits among the medium-large guapotes — smaller than the formidable dovii and managuensis but sharing their predatory build and temperament.
Morphology
Parachromis motaguensis is a substantial cichlid, reaching about 12 in in total length, with males larger than females. The body is robust and moderately elongate, with a large head, a wide gape, and the conical, slightly recurved teeth of a fish-eater. Mature males develop the heavy forehead and incipient nuchal hump common to the larger heroine cichlids, along with longer, trailing tips to the dorsal and anal fins.
The coloration is the source of the trade names. The ground colour ranges from silvery and pale to a warm brassy yellow or pinkish-red, and over it lies a bold, irregular pattern of dark blotches — a broken mid-lateral row coalescing into a ragged band, with further spotting on the flanks and a dark blotch on the caudal peduncle. In breeding and dominant fish the warm ground colour and the contrast of the dark markings intensify dramatically, producing the 'red tiger' appearance prized by keepers. The pattern is variable between individuals and populations, and breeding aquarists have selected for especially red and high-contrast strains.
Sexual dimorphism is moderate: males grow larger and heavier-headed, while ripe females are often shorter-bodied and may show a more golden cast with bolder black blotching when in spawning condition.
Habitat
Parachromis motaguensis is native to the Atlantic (Caribbean) slope of northern Central America. Its core range runs from the Río Motagua basin of Guatemala — the type locality — into the rivers of the Caribbean slope of Honduras, with records from adjacent drainages. It has also been moved around by people and is established outside its native range in places, reflecting its hardiness and adaptability.
The species occupies a range of warm lowland freshwater habitats: rivers and their backwaters, lakes, lagoons and pools. FishBase characterises it as benthopelagic, occurring in fresh and sometimes brackish water, over a pH range of roughly 7 to 8 and moderate hardness (around 9–20 dH). It is tolerant of the warm, variable conditions of Central American lowland rivers, and like several guapotes it copes with a degree of salinity in coastal reaches.
As a large predator it tends to hold position around structure — submerged wood, rock, undercut banks and vegetation edges — from which it hunts, rather than ranging in open water. Temperatures across its range are warm, broadly in the mid-20s to around 86 °F.
Feeding
Parachromis motaguensis is a predator. In the wild its diet is dominated by other fishes, taken by ambush and short pursuit, supplemented by large aquatic invertebrates such as crustaceans and insect larvae, and opportunistically whatever smaller animals it can overpower. The large mouth, gape and dentition are all those of a piscivore, and the species sits high in the food web of its rivers.
In captivity it is unfussy and greedy, readily learning to take large pellets and prepared foods designed for predatory cichlids, alongside frozen and fresh items such as prawn, mussel, earthworms and pieces of fish flesh. Live fish ('feeder' fish) are neither necessary nor advisable — they carry disease risk and offer poor nutrition — and a varied diet of quality prepared and frozen foods keeps the fish in better health. As with all big, robust-feeding cichlids, portion control and good filtration matter: it is easy to overfeed a fish this eager.
Mating
Parachromis motaguensis forms monogamous pairs for breeding, in the manner typical of the substrate-spawning Central American cichlids. Pair formation can be a fraught process in the confines of an aquarium: the species is highly aggressive, and an unreceptive or mismatched female may be harassed or killed, so keepers commonly raise a group together and allow a pair to form, or use a divided tank to introduce a pair safely.
Once a bond is established the pair becomes a formidable territorial unit. Both fish take part in selecting and defending a spawning site and in driving off all other fish from a sizeable territory. Courtship involves lateral displays, jaw-locking and substrate cleaning, and the heightened breeding coloration — the deepening of the red and the black blotching — is most intense at this time.
Breeding
The species is a biparental, open/substrate spawner. The pair cleans a flat surface — a rock, a slab, a broad leaf or a cleared patch of the tank bottom — and the female deposits a large clutch of adhesive eggs, which the male fertilises. Clutches are sizeable, in keeping with the fish's bulk, running to several hundred eggs.
From spawning onward both parents share guard duty in a clear division of labour: the female tends and fans the eggs while the male patrols and repels intruders at the territory's edge. The eggs hatch in a few days, after which the parents move the wrigglers to pre-dug pits and continue to guard them; once the fry are free-swimming the pair leads and defends the school, herding strays back and mounting a determined defence against anything that approaches. Parental care continues for some weeks. This intense, cooperative brood defence is part of what makes the guapotes such compelling aquarium subjects — and also why a breeding pair will dominate and clear even a very large tank.
In the aquarium
Parachromis motaguensis is a 'monster fish' for specialist keepers of large American cichlids, not a community species. Its size, predatory nature and aggression all scale up the requirements for keeping it well, and it should only be taken on by aquarists prepared to provide the space and equipment a 12 in predator demands.
A single adult needs a large tank — on the order of 105 US gal or more, and considerably larger for a pair or any attempt at a mixed big-cichlid setup — with a footprint that gives the fish room to turn and to establish territory. The décor should be robust: large rocks and wood arranged to create defensible sight-breaks and caves, bedded securely so a digging, rearranging cichlid cannot topple them, over a sand or smooth-gravel substrate. Powerful, oversized filtration and a committed water-change schedule are essential to cope with the waste of a large, meaty-feeding fish; warm, near-neutral to slightly alkaline water (pH ~7–8, mid-20s to ~86 °F) suits it. Tankmates, if any, must be other large, robust cichlids or catfish chosen with care, and even then conflict is likely — many keepers house it singly or as a confirmed pair. Small fish are simply food. Given the right scale and a varied predator's diet, it is a hardy, bold, long-lived and characterful fish that interacts strongly with its keeper.
Conservation
Parachromis motaguensis is assessed by the IUCN Red List as Least Concern. It is a widespread, adaptable and locally common predator across the Caribbean slope of northern Central America, with no evidence of broad population decline, and it is not listed on CITES.
The species' tolerance of varied conditions — including disturbed and modified waters, and some salinity — buffers it against many of the pressures that threaten more specialised cichlids, and it has even established populations outside its native range. Localised threats common to Central American rivers, such as pollution, damming and habitat alteration, affect parts of its range, but none is currently judged to put the species as a whole at risk. Its commonness, hardiness and presence in the aquarium hobby (largely through captive breeding) all contribute to its secure status.