Taxonomy & naming
Protomelas sp. "Oxyrhynchus Mix" is not a formally described species. It has no scientific name of its own, no describing author, no year of publication, and no entry in Eschmeyer's Catalog of Fishes, because no taxonomist has published a description establishing it. It is an informal taxon recognised in the field and aquarium literature, principally through Ad Konings's documentation of the Cape Maclear cichlid fauna within Lake Malawi National Park. The placeholder name follows the standard convention for undescribed cichlids: the genus Protomelas, the abbreviation "sp." (species), and a descriptive tag, here "Oxyrhynchus" for its sharply pointed snout and "Mix" for the variable male colouration reported at these islands. Protomelas (erected by Eccles & Trewavas, 1989) is a large genus containing many of Lake Malawi's best-known aquarium species — among them P. taeniolatus, the red empress — several separable mainly by subtle head and fin proportions, which is exactly the kind of character space in which a distinctively snouted, undescribed local form like this one persists in the literature. Until a revision addresses this population directly it should be treated strictly as a Konings-recognised undescribed form, and no authority or date should be attached to it.
Morphology
Protomelas species share a moderately elongate, laterally compressed body with a terminal mouth, the general shape of a sand/intermediate-habitat forager. This population's diagnostic feature is a distinctly pointed, sharp-profiled snout — the character that gives it the name "Oxyrhynchus" — more elongated than the blunter head typical of many related Protomelas, a shape difference rather than a colour trait. Genus-typical adult size for mid-sized Protomelas runs roughly 5.5–8 in; no formal measurement exists for this population specifically. Consistent with the "Mix" tag in its trade name, breeding males are reported to show variable colouration rather than one fixed pattern — a documented complication at Cape Maclear, where several closely related Protomelas forms with overlapping colour ranges occur together, making individual identification difficult by colour alone. Females are expected to be plainer and silvery, the standard haplochromine pattern for concealment while brooding.
Habitat
This form is recorded from Mumbo Island and Thumbi West Island, both within Lake Malawi National Park at Cape Maclear in the southern part of the lake — a region of exceptionally clear water, granite islands, and one of the best-studied cichlid faunas anywhere in the lake, popular with both divers and researchers. Protomelas species typically use sand and intermediate rock-sand habitat around such islands, foraging over open sand near rocky structure. The water column here follows the lake-wide profile: warm, hard, and strongly alkaline, broadly mid-20s Celsius with pH on the alkaline side of neutral. As an undescribed, locality-based form its precise depth range and full distribution beyond the Mumbo–Thumbi West island group are not established.
Feeding
No dedicated feeding study exists for this population specifically. Protomelas as a genus is ecologically varied, including omnivorous sand and intermediate-habitat foragers that pick invertebrates and organic material from the substrate, alongside a few more specialised feeders elsewhere in the genus. The unusually pointed snout of this form may aid probing into narrow crevices or sediment for food, though this is inferred from the shape rather than confirmed by observation. Absent dedicated data, the most defensible characterisation is a benthic omnivore/invertivore, in the general manner documented for the wider genus.
Mating
Like other Lake Malawi haplochromines, this form is presumed polygynous, with males establishing and defending small territories over sand or near rock structure at Cape Maclear's islands, displaying their (individually variable) breeding colour to attract passing females. There is no pair bond. Females move between territories, choose largely on colour and site quality, and spawn briefly before departing with the fertilised clutch in the mouth. No behavioural study specific to this undescribed population exists; the account follows the general pattern documented for Protomelas and Lake Malawi haplochromines more broadly.
Breeding
Protomelas sp. "Oxyrhynchus Mix" is a maternal mouthbrooder, as are all Lake Malawi haplochromine cichlids. After spawning, the female carries the fertilised eggs in her mouth for roughly three to four weeks, feeding little during this period, before releasing free-swimming fry with no further parental involvement from either parent. Clutch size has not been documented for this form specifically; by analogy with similarly sized Protomelas species, a clutch on the order of several dozen eggs is a reasonable expectation rather than a measured fact.
In the aquarium
Protomelas sp. "Oxyrhynchus Mix" is an uncommon aquarium fish, seen in the trade mainly through specialist importers working the Cape Maclear island fauna. Where it is kept, husbandry follows the general template for a sand/intermediate-habitat Protomelas.
A tank of at least 47–59 in suits an adult group, with fine sand substrate and moderate rockwork that leaves generous open sand for foraging, reflecting the natural island habitat. Water chemistry should mirror Lake Malawi's profile: temperature in the mid-20s Celsius, pH roughly 7.7–8.6, and moderately hard to hard water, with prolonged soft or acidic conditions avoided. A single male with several females is the standard social arrangement for a polygynous haplochromine of this kind. Diet should be varied — quality pellet or flake as a staple, supplemented with frozen or live invertebrates — reflecting the genus's general omnivore/invertivore biology, with fatty foods limited given Malawi cichlids' susceptibility to bloat. Because individual males can vary in colour, keepers hoping to maintain a consistent breeding line should source stock from a single, documented collection point.
Conservation
Protomelas sp. "Oxyrhynchus Mix" has not been evaluated by the IUCN, and as an undescribed form without a formal scientific name it has no Red List assessment of any kind. That silence is a statement about taxonomy, not about safety. Mumbo Island and Thumbi West Island lie within the well-protected Lake Malawi National Park, which affords some shelter from the most intensive shoreline pressures elsewhere in the lake, though ornamental collection and the broader basin-wide stresses on Lake Malawi's cichlid fauna remain relevant. No conservation status should be fabricated for it. The honest statement is that it is unassessed and that its true range and status remain to be established by formal study.