Taxonomy & naming
Maylandia koningsi was described in 2018 by Jay R. Stauffer Jr., in a paper titled 'Description of Metriaclima koningsi, a new species (Teleostei: Cichlidae) from Lake Malaŵi, Malaŵi, Africa,' published in Zootaxa (volume 4370). Stauffer placed the species in Metriaclima, the genus he and colleagues had erected in 1997 for these moderately slope-faced mbuna; Eschmeyer's Catalog of Fishes treats Metriaclima as a junior synonym of Maylandia Meyer & Foerster, 1984, and lists the species as valid under the combination Maylandia koningsi, which is used here. The Metriaclima-versus-Maylandia question is a continuing nomenclatural dispute, recently revisited in the literature, but it concerns the correct genus name rather than the validity of the species itself. The fish had circulated among hobbyists and field workers as Metriaclima sp. 'membe deep,' a name that captures both its locality and its deep-water habit. The specific epithet honours Adrianus (Ad) Konings, the prolific author and field researcher of Lake Malawi cichlids, credited by Stauffer for his knowledge of the lake's fishes. The holotype (SAIAB 207704) was collected at Membe Point on the northeastern shore of Likoma Island.
Morphology
Maylandia koningsi is a small mbuna, reaching about 2 in standard length (with the largest measured specimens around 2 in SL). It shows the Maylandia generic characters: a moderately sloped vomer (about 43°) with a swollen rostral tip, bicuspid teeth in the front of the outer tooth row of both jaws, a lower jaw set at roughly 45° to the body axis and slightly longer than the upper, and a habit of feeding at about a right angle to the substrate. Fin counts are 17–18 dorsal spines with 7–9 soft rays and 2–3 anal spines with 7–8 soft rays. Its most distinctive feature is the male coloration: the species lacks the conspicuous vertical flank bars typical of most Maylandia and instead presents a blue body with a dark submarginal band in the dorsal fin — a combination shared only with Maylandia usisyae, from which koningsi males differ in being blue rather than gold on the flank. Females are entirely brownish-yellow, resembling those of Maylandia flavifemina and Maylandia phaeos; koningsi is separated from the former chiefly by its smaller maximum size (about 2 in SL versus up to 3 in) and from the latter by a shorter snout.
Habitat
Maylandia koningsi is endemic to Lake Malawi and, within it, known from the rocky shores around Likoma Island — the type series coming from Membe Point on the island's northeastern coast (about 12°03′S 34°45′E). What sets its habitat apart from that of most mbuna is depth: it is described as a deep-water form, usually found below 49 ft, well beneath the shallow, sunlit rock zone where the great majority of mbuna live. This makes it part of a less-studied deep-rock community whose members are harder to collect and observe. The general lake conditions apply — hard, alkaline water with a pH near 8 and warm, tropical temperatures — but the deeper habitat means dimmer light and cooler, more stable conditions than the surf-washed shallows. As with all rock-restricted mbuna, the population is tied to a particular stretch of rocky coast and is effectively isolated by the open water and sandy gaps that these fish do not readily cross.
Feeding
No dedicated dietary study has been published for Maylandia koningsi, but its anatomy and the ecology of its genus identify it as an algae-comber in the standard mbuna mould. The description explicitly notes that the fish feeds at roughly a 90° angle to the substrate, and the bicuspid outer teeth are the tools of an animal that combs the algal film — the Aufwuchs — from rock surfaces. FishBase places it at an estimated trophic level of about 2.4, the value typical of a largely herbivorous biofilm-grazer that also ingests the small invertebrates and detritus living within the algal mat. In its deeper, dimmer habitat the algal turf is thinner than in the brightly lit shallows, but the same combing strategy applies. As with related mbuna, the species is best regarded as a grazing omnivore weighted heavily toward algae, taking animal food opportunistically rather than as a specialist predator.
Mating
Courtship has not been described in detail for Maylandia koningsi, but the species can be expected to follow the uniform mbuna pattern of polygynous maternal mouthbrooding with no pair bond. A sexually active male assumes his full blue nuptial coloration, with the diagnostic dark submarginal band in the dorsal fin prominent, and defends a territory among the rocks. He courts passing females with lateral displays and quivering, attempting to lead a receptive female to a spawning site on cleared rock or sand. The familiar mbuna spawning sequence then applies: the female deposits a small number of eggs and immediately takes them into her mouth, and the egg-spot markings on the male's anal fin are thought to play their usual role in ensuring fertilisation occurs within the female's buccal cavity. The male provides no parental care and continues to court other females. The deep-water setting may influence timing and density of breeding, but the basic mechanics are those of the genus.
Breeding
Maylandia koningsi is a maternal mouthbrooder, in line with the entire genus and the wider mbuna assemblage. After spawning, the female carries the fertilised eggs and then the larvae in her mouth, brooding them for roughly three weeks while feeding little or not at all, until they are released as free-swimming fry; for a short time afterward she may shelter the fry in her mouth when threatened. Given the species' small adult size — females maturing at only around 2 in SL — clutches are likely to be small, on the order of a dozen to a couple of dozen eggs, though no clutch count has been published. There is no documented aquarium breeding record specific to koningsi, reflecting how recently it was described and how little it has entered the trade. The account here is therefore inferred from the highly consistent and well-documented breeding biology of Maylandia and the mbuna generally rather than from direct observation of this species.
In the aquarium
Maylandia koningsi is, as of its 2018 description, essentially unknown in the general aquarium hobby and has no established trade presence or body of keeping experience; it circulated only narrowly as 'Metriaclima sp. membe deep' among specialists. Any husbandry guidance is extrapolated from its close relatives and its known habitat and should be treated as provisional.
If kept, it would call for a standard Malawi mbuna setup scaled to a small, peaceful-for-an-mbuna rock-dweller: a tank with abundant stacked rockwork forming caves and territories, a sand substrate, and the hard, alkaline water (pH around 8, mid-20s Celsius) the lake demands, maintained by strong filtration and careful husbandry. As an algae-comber it should be fed a Spirulina- and vegetable-based diet rather than rich, fatty or high-protein foods, which predispose mbuna to digestive 'bloat.' Its deep-water origin suggests it may appreciate slightly subdued lighting and would not need the brightest, most sun-blasted aquascape. Like other mbuna it is territorial and best kept as one male with several females among robust tankmates of similar temperament. For now, though, this is a fish of interest mainly to dedicated Malawi specialists rather than one with a real aquarium track record.
Conservation
Maylandia koningsi has not yet been evaluated by the IUCN Red List and currently carries no formal conservation status, which is unsurprising for a species described only in 2018. Its conservation profile is nonetheless easy to sketch and gives some cause for caution: it is a narrow-range endemic known only from the rocky coast around Likoma Island, and, like other rock-restricted mbuna, it is effectively confined to that habitat with little ability to disperse across the intervening open water. Its deep-water habit may afford some buffering from the most intense shallow-water fishing and shoreline disturbance, but it equally means the species is poorly surveyed and its true range and abundance are uncertain. The broad pressures on Lake Malawi — heavy fisheries, sedimentation and nutrient input from a growing lakeshore population, and climate-driven changes to the lake — apply to the deep-rock community as they do to the shallows. A future assessment would most likely weigh the small known range against the limited evidence of immediate threat; until then the honest position is that the species is unassessed and its status genuinely unknown.