Taxonomy & naming
Maylandia sp. "Aggressive Zebra Maleri" has no describing author and no entry in Eschmeyer's Catalog of Fishes; it is an informal hobby trade name, not a scientific one, and the "Aggressive" spelling — missing the second "g" — is reproduced here exactly as it circulates in the trade and in the malawi.si database rather than silently corrected. Maylandia was split from the larger Pseudotropheus complex and named for the German aquarist Hans J. Mayland; it contains the bulk of the classic Malawi "zebra" mbuna, a group whose barred, blue-and-black pattern recurs, with local variation, at dozens of rocky localities around the lake. The "Maleri" element of this name references the Maleri Islands, a well-documented southern-lake locality famous for a particular zebra colour type; when applied to a fish recorded at Nakantenga Island, well north of Maleri, the name is most plausibly describing a resemblance in colour pattern to the Maleri-type zebra rather than asserting the fish actually originates there — a naming pattern not unusual in the trade, where a well-known phenotype name gets attached to a similar-looking population found elsewhere. The "Aggressive" qualifier follows the convention of flagging a form as more territorial than a co-occurring, similar-looking population at the same site.
Morphology
The form is expected to follow the classic Maylandia zebra-complex build: a moderately deep, laterally compressed body, blunt head, and a mouth suited to scraping algae, carrying the vertically barred blue-and-black "zebra" pattern that gives the whole species complex its common name. The precise bar count, background blue shade, and any fin-edge colouring specific to this Nakantenga population have not been formally described. Genus-typical size for Maylandia zebra-type mbuna runs to roughly 3.5–5 in total length, with some locality populations, including forms bearing the "Maleri" name, noted in the hobby literature for running toward the larger end of that range; no validated maximum has been published specifically for this form.
Habitat
Nakantenga Island is a small, rocky island locality on Lake Malawi's central-west shore near Senga Bay, with the steep rock faces and boulder fields typical of zebra-complex mbuna habitat. This form was recorded there rather than at the Maleri Islands themselves. Specific depth data are not available, but genus-typical Maylandia occupy rocky shallows from roughly 7–49 ft. Like other mbuna, this form is expected to show high site fidelity to a home rock pile, rarely straying far over its lifetime — the kind of limited dispersal that Malawi researchers have long linked to the group's extreme rate of local diversification between rocky outcrops separated by even short stretches of open sand or deep water.
Feeding
As in other Maylandia, this form is presumed to be an aufwuchs grazer, scraping algal film and associated diatoms and small invertebrates from rock surfaces with the genus's characteristic close-set, fine teeth. No feeding study specific to this form has been published. The genus's fine, close-set grazing teeth are replaced on a continuous cycle through the fish's life, wearing down against rock and being renewed from beneath — a dental adaptation shared across the mbuna grazing guild and one of the classic trophic specialisations catalogued in Fryer and Iles' 1972 survey of the Malawi cichlid radiation. Zebra-complex Maylandia are generally regarded as somewhat more food-opportunistic than the strictest algae specialists among the mbuna, occasionally taking small invertebrates encountered while grazing rather than feeding on algae alone.
Mating
Maylandia breeding follows the standard mbuna pattern: territorial males hold a cave or rock crevice and display to visiting females before spawning. The "aggressive" qualifier in the trade name suggests unusually vigorous territorial defence relative to a similar sympatric population, consistent with general zebra-complex mbuna behaviour, though this form's courtship has not been directly documented. The egg-spot display typical of Malawi mbuna almost certainly applies here too: orange or yellow ocelli on the male's anal fin mimic eggs, and the female's attempts to pick them up during spawning are what bring sperm into contact with the eggs already in her mouth.
Breeding
Reproduction is maternal mouthbrooding, as in all Maylandia: after spawning at the male's territory, the female carries the fertilised eggs alone in her mouth for roughly three weeks before releasing free-swimming fry. Clutch size has not been documented for this form; genus-typical broods for zebra-complex Maylandia run to several dozen eggs, generally larger than the average for smaller-bodied mbuna. The roughly three-week incubation typical of Malawi mbuna is presumed to apply here; brooding females generally reduce feeding and become more reclusive for the duration, releasing fry that are immediately capable of finding shelter among the rocks.
In the aquarium
This is a scarce, locality-specific form available mainly through specialist Malawi cichlid importers. Standard mbuna husbandry applies: a heavily rock-aquascaped tank with plenty of sightline breaks, hard alkaline water matching Lake Malawi chemistry, and a vegetable-forward diet suited to its grazing habit. Given the behavioural cue in its name, keepers should plan for a more territorial fish than an average zebra-type mbuna and provide correspondingly more space and females per male. Rockwork should be built directly on the tank floor or a false bottom rather than stacked on loose substrate, both for stability and to give the fish the cave structure it needs; a primarily vegetable diet, kept light on protein, mirrors its natural grazing intake and reduces the risk of bloat, a common ailment in mbuna fed too rich a diet.
Conservation
As an undescribed form, "Aggressive Zebra Maleri" has not been assessed by the IUCN and carries no conservation status. Zebra-complex mbuna are among the most heavily collected Lake Malawi cichlids for the aquarium trade, and easily accessible rocky localities like Nakantenga Island can see local depletion from sustained collecting pressure, but no population data specific to this form are available. This reflects a wider pattern in Malawi mbuna conservation: single-locality, undescribed forms fall outside any formal assessment process by definition, regardless of how narrow their actual range may be — a gap that matters given how many mbuna populations are restricted to one rock reef or a short stretch of shoreline.