Taxonomy & naming
Lethrinops chilingali was described in 2023 by George F. Turner, David A. Crampton and Martin J. Genner, in Zootaxa (volume 5318, issue 4, page 518), in a paper titled 'A new species of Lethrinops (Cichliformes: Cichlidae) from a Lake Malawi satellite lake, believed to be extinct in the wild.' Eschmeyer's Catalog of Fishes records the name as valid: Lethrinops chilingali Turner, Crampton & Genner 2023, in family Cichlidae, subfamily Pseudocrenilabrinae. The holotype (BMNH 2023.1.11.1), a 3 in SL female, was collected from seine catches in Lake Chilingali (12.94°S, 34.21°E) over 22–24 June 2009; twenty paratypes (2.5–3 in SL) came from the same catches. The genus Lethrinops, erected by Regan in 1922, is a group of sand-dwelling Malawi haplochromines defined chiefly by their lower-jaw dental arcade. The authors assigned chilingali to Lethrinops on the form of that arcade and by the absence of traits diagnostic of the similar genera Ctenopharynx, Taeniolethrinops and Tramitichromis, and the absence of the enlarged cephalic lateral-line pores seen in Alticorpus and Aulonocara. Its closest relative is Lethrinops lethrinus; chilingali is distinguished by a broken (rather than continuous) horizontal flank stripe in females and non-territorial males, a relatively shorter snout, a shorter lachrymal bone and a less ventrally placed mouth. The epithet is a noun in apposition taken directly from Lake Chilingali, the type locality.
Morphology
Lethrinops chilingali is a small cichlid. Wild type specimens ran 2.5–3 in standard length, with the holotype female at 3 in SL; captive-reared fish grew somewhat larger, up to about 4 in SL, and these larger individuals were used for allometric comparisons but excluded from the type series. The body is moderately elongate, with relatively long pectoral fins that reach past the first anal spine, short pelvic fins (except in the largest mature males), a crescentic caudal fin, and a large, round eye that nearly touches the upper profile in side view. The flank scales are weakly ctenoid, becoming cycloid dorsally and anteriorly. Females and immature or non-territorial males are countershaded — pale sandy-brown above, silvery on the flanks and belly — and marked by a midlateral row of dark spots and stripes running from behind the operculum to the caudal peduncle, typically broken into three to six separate melanic elements; this broken stripe is a key diagnostic feature separating it from the continuous-striped Lethrinops lethrinus. Dominant males develop stronger markings during display: a dark lachrymal/eye stripe, dark pelvic and anal fins, dark caudal margins, a dark lower head and chest during courtship, and a row of pale yellow egg-spots (4–18) on the anal fin.
Habitat
This is where the species' identity must be stated plainly: Lethrinops chilingali is NOT a fish of Lake Malawi proper. It is endemic to Lake Chilingali, a small satellite lake roughly 3 mi long and at most 1 mi wide, lying in the Kaombe River catchment near Nkhotakota in central Malawi, and connected to Lake Malawi only intermittently via the Kaombe River, which meanders about 7 mi to reach the main lake. Satellite lakes like this sit in the catchment of a much larger lake and can drive speciation by isolating populations — chilingali is thought to have diverged from its Lake Malawi sister lineage after receding lake waters stranded its ancestors in the Chilingali basin during the Pleistocene. The lake itself has a turbulent recent history: a dam built across its single outflow around 1992 raised the water level and merged two historically separate basins (Lake Chikukutu to the south and Lake Chilingali to the north); the dam later collapsed and the lake largely drained, leaving basins only about a metre deep by 2016, before a new dam refilled it in 2019. The water was highly turbid whenever the lake was visited between 2004 and 2009, so the species' behaviour in nature was never directly observed in the wild.
Feeding
Lethrinops, as a genus, are sand-sifting or 'winnowing' feeders: they take a mouthful of loose sand or mud, tumble it briefly, and eject it through the mouth and gill covers, retaining and swallowing small prey. Their subterminal mouths, flat lower jaws and small teeth are associated with this mode. Lethrinops chilingali appears to depart somewhat from the typical pattern. Gut contents of specimens sampled in 2009 consisted largely of Chaoborus (phantom-midge) larvae and pupae, together with cladocerans and larger invertebrates including dragonfly (odonatan) nymphs and caridinid shrimps, but with very little detritus — which the authors suggest points to more midwater feeding than is usual in the genus. In captivity, females, non-territorial males and juveniles aggregate in loose groups and feed not only in the sediment but on rocks, plants and even at the water surface, reinforcing the picture of a flexible feeder rather than a strict sand-sifter.
Mating
Dominant male Lethrinops chilingali are territorial and court in typical haplochromine style: fins spread wide, body held horizontal or head-up, with rapid darts between the female and the spawning site amid bouts of circling and quivering, the pair alternating head-to-anal-fin 'T-positions' over the substrate. Notably, male coloration and aggression vary a great deal and seem to peak only when females are close to spawning, often appearing quite subdued otherwise. The species is not a communal lek breeder in the wild: in captivity, dominant males hold smaller territories and engage in frequent boundary disputes rather than gathering at a shared arena. There is little sign of bower construction — on sand or gravel, a dominant male simply tries to lead the female to a slight depression beside an object such as a rock or piece of wood, which differs from reports of more elaborate spawning structures in the related Lethrinops lethrinus.
Breeding
Like its relatives, Lethrinops chilingali is a maternal mouthbrooder. By analogy with the closely related Lethrinops lethrinus, females brood the young in the buccal cavity until they are capable of independent feeding; as the fry absorb their yolk, they show through the female's buccal membrane as a dark area. Unlike fry-guarding cichlids such as Astatotilapia or Oreochromis, brooding females do not develop the dark 'warpaint' eye and head stripes typical of guarders. Because the species has been maintained and bred in captivity — indeed, captive populations in Europe were for a time thought to be the only ones left — its courtship and spawning are better documented than for most obscure Malawi-region haplochromines, even though it was never observed breeding in its turbid home lake. The captive strains held at institutions including Bangor University were the basis for the larger comparative specimens in the original description.
In the aquarium
Lethrinops chilingali occupies an unusual niche: it is not a commercial aquarium fish, yet it is one of the better-known small Malawi-region Lethrinops in captivity precisely because of its conservation story. Captive breeding populations have been maintained in European aquaria — at universities and within zoo and aquarium conservation networks — as an insurance against extinction and a potential source for reintroduction. These captive stocks are the reason much of what we know about the species' behaviour exists at all.
For a hobbyist, the relevant husbandry is extrapolated from captive observations and the genus: a spacious tank with a sand substrate suited to its sifting and group-feeding habits, stable hard alkaline water broadly in the Lake Malawi range, and a varied diet of small invertebrate foods. The fish is gregarious outside breeding, with males becoming territorial when females approach spawning. It is not, however, a fish to expect in the general trade; where it exists in aquaria it is essentially a managed conservation population rather than a trade commodity, and anyone keeping it should treat it as part of an insurance lineage to be bred carefully rather than mixed and hybridised.
Conservation
Honesty about the status here matters. The 2023 description recommended that Lethrinops chilingali be listed as Extinct in the Wild (EW) on the IUCN Red List, because the species had not been positively recorded in nature since 2009 — its lake had drained after a dam collapse, an introduced tilapia had become abundant during restocking, and only captive populations were known to survive. Crucially, that EW status was a recommendation, not a formal listing: as of this writing the species remains Not Evaluated by the IUCN. And the story has since improved. A field survey in 2024, led by Professor George Turner with Chester Zoo and Malawian partners, rediscovered Lethrinops chilingali — now reported as abundant in the northern part of the refilled Lake Chilingali, and present more widely in the Kaombe catchment (including the main river channel) and in a further river system to the south, an actual range extension. So the fish is no longer best described as extinct in the wild; it is a narrow-range satellite-lake endemic that came alarmingly close and appears to have recovered. (Its co-endemic, the undescribed Rhamphochromis sp. 'chilingali,' was not found in 2024 and is now presumed extinct in the wild — a reminder of how fragile these tiny isolated faunas are.) The principal threats to chilingali remain habitat instability from dam management and water-level swings, pollution, and introduced species in a very small lake.