Taxonomy & naming
Paretroplus damii was described by the Dutch ichthyologist Pieter Bleeker in 1868, in a short paper on three new Madagascan 'Chromidoïdes' published in the proceedings of the Royal Academy of Sciences in Amsterdam. It is the type species of the genus Paretroplus, which Bleeker erected in the same work, so the species sits at the nomenclatural foundation of the entire damba assemblage. The two syntypes (held at the Naturalis collection in Leiden, RMNH, with material also catalogued under Tervuren registers) came from Lake Pambilao on the island of Nosy Be, off the northwest coast — a type locality that has proved frustrating, as no further specimens have been recovered there despite repeated expeditions, and the original types are in poor condition. George Boulenger's 1899 revision of the African and Syrian cichlids briefly carried the name as a misspelled 'Paretroplus dammi,' but the original spelling stands. The species was monographed in John Sparks's 2008 phylogeny and revision of the subfamily Etroplinae (Bulletin of the American Museum of Natural History 314), which remains the definitive treatment of the genus. Sparks placed Paretroplus damii in a clade with the rheophilic species Paretroplus nourissati, Paretroplus tsimoly, and P. lamenabe; within that group damii is the deepest-bodied and, in evolutionary terms, the oldest branch, and de Rham and Nourissat (2005) had originally given it a group of its own. Two regional forms — Paretroplus sp. 'dridrimena' from the rivers draining the Massif d'Ambre and Paretroplus sp. 'ventitry' from the Mahanara drainage — have been suggested as possibly distinct, but Sparks found no diagnostic features to separate them and retained them within damii. Within the broader subfamily, the genus Paretroplus is not most closely allied to mainland African cichlids at all: its sister group is the Asian Etroplus and Pseudetroplus of India and Sri Lanka, a Gondwanan distribution that makes the dambas living relics of the cichlid family's deep history.
Morphology
This is a large cichlid: FishBase lists a maximum of 15.5 in total length, and de Rham and Nourissat (2005) reported a specimen close to that figure, making damii one of the bigger dambas. The body is deep, oval and strongly laterally compressed, with the curved frontal profile, small mouth and deeply emarginate (crescent-shaped) caudal fin typical of the genus; the high anal-spine count (nine to eleven spines, against three in all other native Madagascan cichlids) is a hallmark of Paretroplus. Fin counts run to 18–20 dorsal spines with 11–16 soft rays. The diagnostic feature, present at all ages, is a triangular black patch in the pectoral axilla combined with the absence of the series of vertical flank bars that mark most congeners; in preservation damii is the only Paretroplus that is a solid grayish-brown to brown with no barring. In life, an unstressed fish shows the trait that earns it the trade name 'yellow-wedged': a broad vertical pale-yellow band across the anterior half of the flank, which can deepen to brick red. Juveniles carry their own unique mark — a dark blotch ringed by a clear (hyaline) halo near the base of the rear soft dorsal fin. The mouth bears molariform pharyngeal dentition and the snail-picking teeth at the tip of the upper jaw seen across the genus, though damii is reported to be less single-mindedly mollusk-crushing than the disk-shaped dambas. Documented sexual dimorphism is slight: as in most substrate-spawning Paretroplus the sexes are similar, with mature males tending to grow somewhat larger and heavier-headed and ripe females rounder in the body, but there is no reliable external colour or finnage difference, and sexing is generally done by vent inspection at spawning.
Habitat
Paretroplus damii is endemic to northwestern and far northern Madagascar, within the Northwestern Madagascar freshwater ecoregion (FEOW 580) — a region of floodplain rivers, oligotrophic shallow lakes and steep clearwater streams that, fed by the Tsaratanana Massif's high rainfall, holds the richest and most endemic cichlid fauna on the island. Among the dambas, damii is unusual in being widespread rather than confined to a single basin: its range runs from the Anjingo–Ankofia drainage and Lake Andrapongy in the south northward to the Sahinana and Sampiana rivers draining the western slopes of the Montagne d'Ambre, and it is reported from the Betsiboka, Mahajamba, Mahavavy du Nord, Mananjeba and Sambirano systems along the way. It occupies rivers, river pools and lakes over substrates of sand, rock or mud, in habitats where rooted aquatic vegetation is generally absent. Its water chemistry is strikingly variable. Populations in the granitic Sambirano basin — for instance in the Ramena River, whose name evokes 'red water' — live in soft, slightly tea-stained, acidic water at around pH 6.5 and very low hardness (no more than about 1 °dGH); yet in some floodplain lakes the same species occurs in distinctly alkaline water at pH 8 or above, still with very low hardness (2–3 °dGH). This is consistent with the regional pattern: northwestern Madagascan waters tend toward neutral-to-alkaline pH and high carbonate alkalinity but low overall mineralization. Across these settings the water is warm, and temperatures frequently exceed 86 °F. The fish is demersal and, like most dambas, occupies shallow floodplain and riverine habitat rather than deep water; the floodplain lakes of the ecoregion are themselves described as extremely shallow and turbid.
Feeding
No formal gut-content study of Paretroplus damii has been published, and FishBase carries no diet data beyond a model-estimated trophic level of about 2.8. What can be said is inferred from its anatomy and from the genus. Like all Paretroplus it carries robust molariform pharyngeal teeth and the small snail-picking teeth at the front of the upper jaw, the toolkit of a mollusk-eater; radiographs of related dambas have shown guts packed with crushed gastropod shells, and it is generally assumed that snails form a meaningful part of the diet across the genus, supplemented by algae and other benthic material. Within that frame, observers consider damii less committed to hard-shelled prey than the deep, disk-bodied dambas — it 'does not appear to be as enthusiastically malacophagous,' in one keeper's phrase — and in practice it behaves as a broad benthic omnivore, taking invertebrates, plant matter and whatever the substrate yields. In its turbid, vegetation-poor floodplain habitat it functions as a generalist forager of the bottom and lower water column rather than a narrow dietary specialist.
Mating
Paretroplus are social, schooling cichlids outside the breeding season, and damii is no exception; the genus is best kept and observed in groups, within which pairs form. Reproduction follows the strong seasonality of the Madagascan dry season: across the genus, spawning runs from roughly August through October, the back half of the dry season. A ripe pair separates from the group and courts around a chosen site, defending it against conspecifics. As a monogamous substrate spawner damii forms a genuine pair bond, and both fish take part in territory defence. One of the most intriguing aspects of damba reproduction concerns who guards the brood. In most biparental substrate-spawning cichlids the female does the close tending; but when Patrick de Rham first bred the related Paretroplus nourissati in 1995 it was the male that stayed with the eggs and wrigglers, a reversal he found surprising, and at least one breeder has reported the same male-led guarding in damii. Whether this is the rule or an occasional occurrence remains unsettled — it has not been consistently replicated — but it is a behaviour worth watching in this species. damii has a reputation as one of the more aggressive paretropliines, though keepers temper that by noting it is no worse than many comparably sized Central American cichlids.
Breeding
Paretroplus damii is a monogamous, biparental substrate spawner. Dambas that live in lakes and river pools, as damii largely does, spawn on open substrate — a rock, a waterlogged branch, or even the bare aquarium bottom where the pair first excavates a shallow depression — rather than retreating into caves, although the genus includes rheophilic cave-spawners and some species will use a cave if one is offered. The eggs are adhesive, large, and a distinctive salmon-orange; both parents share the care of eggs, wrigglers and free-swimming fry, with the caveat noted above that in this lineage the male may take the leading guarding role. No precise wild clutch count is published for damii specifically; genus-typical spawns from comparable large Paretroplus run to a few hundred adhesive eggs. The species matures relatively young for so large a cichlid — around 12 to 18 months — though it grows slowly thereafter. Wild reproduction is keyed to the dry-season window of August–October; in captivity, warmth and good conditioning are the main triggers, with breeders raising temperature above about 81 °F for spawning. The single most important lesson from captive breeding concerns the fry: experienced keepers stress that newly free-swimming damba fry should be fed exclusively on live food — Artemia nauplii work well — and that this live feeding must continue uninterrupted for at least the first three months, or the brood is easily lost.
In the aquarium
Paretroplus damii was first bred in captivity in the early 2000s in the outdoor pools of the French aquarist Jean-Claude Nourissat, from fish collected in 1999 at Lake Babano in the Mananjeba basin north of Ambilobe; juveniles from that line were distributed among European aquarists. It is a rare and demanding fish in the hobby, suitable for committed keepers rather than casual ones — and one whose continued presence in captivity has genuine conservation value, since wild dambas are in steep decline.
This is a large, robust, moderately aggressive cichlid that needs space. A pair can be managed in a tank around 51 in long and 19.5 in wide, but the genus does better in larger quarters; a footprint giving on the order of 105 US gal should be regarded as a sensible minimum, with considerably more being better, and the larger-growing dambas are often given 185 US gal or more. Because Paretroplus are social and prone to intraspecific friction when paired in isolation, keeping a group so that fish can pair off naturally — and subordinate individuals can keep their distance — reduces aggression and is the usual route to a compatible pair. A single-species tank is recommended if breeding is the goal.
Water should be warm, well filtered and frequently changed, with a pH at or above neutral as a default for general maintenance; the species itself is chemically flexible, tolerating anything from soft acidic blackwater (around pH 6.5) to hard-carbonate alkaline water (pH 8+), always at low to very low general hardness. A maintenance temperature in the mid-to-upper 20s °C suits it, raised toward 81–82 °F for breeding; these are genuinely warm-water fish that in the wild often experience temperatures above 86 °F. Décor is best kept simple and naturalistic: a fine sand substrate, smooth rocks and waterlogged wood. Rooted plants are largely pointless — they do not occur in the fish's habitat, and Paretroplus will nibble them — so a hardscape-only layout is both more authentic and more practical.
Feeding is straightforward. damii accepts a wide range of quality prepared and frozen foods; frozen insect larvae and crustaceans are excellent for conditioning, cultured snails (including hard-shelled Malaysian trumpet snails) play to the genus's mollusk-eating nature, and some vegetable matter — blanched spinach, spirulina-based foods — rounds out an omnivore's diet. The common husbandry mistakes are predictable: undersizing the tank, attempting an isolated pair in cramped quarters and losing one fish to aggression, neglecting the heavy water-change regime these big, messy cichlids require, and — when breeding — failing to provide the months of continuous live food the fry depend on. Tankmates, if any, should be robust, similarly sized fishes that can hold their own; small or timid companions are a poor match for a large, territorial damba.
Conservation
Paretroplus damii is assessed by the IUCN Red List as Vulnerable (VU, criterion B1ab(iii)), in an assessment by Ravelomanana and Sparks dated 24 June 2016 (published 2020). The listing reflects a restricted and fragmenting range — an extent of occurrence estimated at roughly 4,435 mi² across about six locations in northwestern Madagascar — under continuing decline in habitat quality. The principal threats are heavy fishing pressure (Paretroplus are valued food fishes in Madagascar and have long supported local fisheries), deforestation in the catchments, and general habitat degradation; the population trend is recorded as unknown. damii is among the less acutely threatened members of its genus precisely because it is comparatively widespread: several of its relatives — P. maculatus, Paretroplus menarambo, Paretroplus dambabe, Paretroplus gymnopreopercularis — are Critically Endangered, each clinging to a single basin or lake, and the genus as a whole is regarded as one of the most imperilled in the entire cichlid family, pressured by habitat loss, overfishing and introduced species such as tilapia and snakeheads. Several dambas survive in better numbers in aquarists' tanks than in the wild, and captive maintenance by dedicated hobbyists and public aquaria is an explicit part of the conservation response. For a fish whose evolutionary lineage reaches back to the breakup of Gondwana, the stakes of that effort are considerable.