Taxonomy & naming
Otopharynx sp. "Decorus Featherfin" has no describing author, no publication date, and no entry under a validated name in Eschmeyer's Catalog of Fishes. The trade name follows the standard convention for an undescribed form allied to a known species: the genus, a reference to the described relative Otopharynx decorus (Trewavas, 1935) — Latin for "comely" or "elegant" — and "Featherfin," a descriptor for elongated, feather-like fin rays. Otopharynx decorus is itself distinguished within its genus partly by an unusually high dorsal-fin ray count (13 or 14 soft rays, versus fewer than 12 in most relatives), and its generic placement is debated, with some authors considering it better assigned to the closely related genus Mylochromis. Whether the Kande Island population represents a genuinely distinct, more extravagantly finned form, or simply well-developed individuals of ordinary O. decorus, has not been settled by any published study. It should be treated as an unresolved, undescribed entity.
Morphology
As its trade name suggests, breeding males of this form are reported to carry noticeably elongated dorsal and anal fin rays — a "featherfin" trait layered onto a species, Otopharynx decorus, already known for an unusually high dorsal ray count among Otopharynx. Otopharynx decorus itself reaches about 7 in total length, has a notably small mouth for a sand-dwelling haplochromine of its size, and carries the genus's three-spot melanic pattern, though the blotches are often faint and hard to see in the subdued light of its deeper habitat. That size figure is used here only as a genus/species-typical reference rather than a direct measurement of the Kande Island population. No formal morphometric study specific to this form has been published, and the extent of its finnage beyond the general "featherfin" description is undocumented.
Habitat
Otopharynx sp. "Decorus Featherfin" is recorded from Kande Island, a small island in the northern part of Lake Malawi long popular with Malawi cichlid collectors and exporters. Otopharynx decorus, the described relative this form is named after, forages over open sand at depths reported to reach around 66 ft in subdued light, typically in small groups of up to about six fish, and the Kande Island population is presumed to occupy broadly similar sandy, moderate-depth habitat. The surrounding water follows the general Lake Malawi profile — warm, alkaline and well-buffered.
Feeding
Otopharynx decorus feeds as a visual sand-sifting insectivore: it uses its large eyes to scan the substrate closely, then bites into the sand once it locates hidden prey, taking mainly invertebrates buried within the substrate rather than picking food from the surface. Otopharynx sp. "Decorus Featherfin" is presumed to feed similarly, though no dedicated feeding study has been published for this Kande Island population specifically.
Mating
No courtship behaviour has been documented specifically for this form. Field surveys of Otopharynx decorus itself have not found clearly territorial, breeding-dressed males defending a spawning site; occasional individuals within foraging groups show partial nuptial colour, but behave as foragers rather than territory holders, and it remains speculative whether the species moves onto rocky substrate to breed. If the Kande Island form follows the reproductive pattern universal to Lake Malawi's haplochromines, mating would still be maternal mouthbrooding with polygynous, lek-style spawning, but the courtship sequence and spawning site have not been directly observed for either the described species or this population.
Breeding
As with all Lake Malawi haplochromines, reproduction is presumed to be by maternal mouthbrooding: the female would incubate the fertilised eggs in her buccal cavity for roughly three weeks, fasting throughout, before releasing free-swimming fry, which she may continue to shelter in her mouth when threatened. Clutch sizes in haps of this size are typically modest, on the order of a few dozen eggs, but no figures have been recorded specifically for this population. Even for the described relative, Otopharynx decorus, breeding has never been directly observed in the field, so the reproductive details given here are inferred from the wider Malawi haplochromine flock rather than measured.
In the aquarium
Otopharynx sp. "Decorus Featherfin" reaches the hobby occasionally through specialist Malawi cichlid importers working the northern lake's export points, including Kande Island. A tank for it should provide a sand substrate with moderate rockwork, reflecting the sand-and-intermediate habitat of its described relative, and open swimming space appropriate to a fish that may reach a respectable size. Water chemistry should follow the Lake Malawi standard — alkaline and well-buffered, pH roughly 7.5 to 8.5, temperature in the mid-20s Celsius. A varied invertivore diet of quality pellets and meaty frozen foods such as bloodworm and mysis suits it, avoiding rich mammalian-based feeds. Given the population's reported elongated finnage, keepers should expect fin damage from boisterous tankmates to be a particular risk, and calm, similarly sized companions are advisable.
Conservation
Otopharynx sp. "Decorus Featherfin" has not been evaluated by the IUCN and, as an undescribed form, has no Red List status of any kind. Its described relative, Otopharynx decorus, is assessed as Least Concern based on its comparatively wide, lake-spanning distribution, but that status does not extend to the Kande Island population specifically. No population-specific data exist to assess whether this form is affected by ornamental collection or other localised pressure at Kande Island. The honest statement is that it is unassessed.