Taxonomy & naming
Otopharynx spelaeotes belongs to the genus Otopharynx, a group of Lake Malawi haplochromines significantly revised in Eccles and Trewavas's 1989 study of the lake's cichlid genera, which redefined the genus's boundaries and reassigned a number of species among Otopharynx and its relatives. The genus name combines the Greek "otos" (ear) with "pharynx" (throat), a reference to anatomical features of the pharyngeal region used in the genus's diagnosis. The species epithet "spelaeotes" derives from the Greek "spelaion" (cave), meaning "cave dweller" — a name that describes the species' association with rock crevices and cave-like shelter rather than open water or open sand. Eschmeyer's Catalog of Fishes is the authority for the species' currently accepted valid name.
Morphology
Otopharynx spelaeotes has the moderately elongate body typical of the genus, estimated at roughly 4.5–5 in as an adult, in the mid-size range for Malawi haplochromines. Many Otopharynx species show striking male breeding colour, often built around yellow, orange, or blue tones, though the specific pattern for this species is not confidently documented here. Its cave- and crevice-associated habits, implied directly by its species name, suggest a somewhat shier, less conspicuous fish by day than the open-water Otopharynx species, though this behavioural inference should be treated as reasoned rather than directly confirmed.
Habitat
The species is documented from sites including Jalo Reef, Makonde, and Ndumbi Point, spanning a range along the lake's shoreline. Consistent with its name, it is associated with rock crevices and cave-like recesses rather than open sand or unbroken rock reef, sheltering within these structures and likely emerging to feed. Water conditions follow the lake's usual profile: warm, hard, and strongly alkaline, with the species occupying the moderate depths typical of rock- and crevice-associated Malawi haplochromines.
Feeding
Otopharynx as a genus includes species with a range of feeding strategies, from open-water zooplanktivores to benthic invertebrate feeders associated with rock and sand. Given Otopharynx spelaeotes' apparent crevice- and cave-dwelling habits, it likely forages for small invertebrates in and around rocky shelter rather than feeding primarily in open water, though the precise diet of this specific species is not confidently documented here and this description should be treated as a reasonable inference from its habitat rather than a directly confirmed fact.
Mating
As in other Lake Malawi haplochromines, Otopharynx spelaeotes is understood to be polygynous with no lasting pair bond. A number of Otopharynx species use caves or crevices as spawning sites, with males establishing and defending such a shelter as a display and mating territory rather than an open patch of sand or rock — a pattern that would fit naturally with this species' cave-associated habits, though species-specific courtship behaviour has not been separately documented here.
Breeding
Otopharynx spelaeotes is a maternal mouthbrooder, as are essentially all Lake Malawi haplochromines. Following spawning, the female takes the fertilised eggs into her mouth and broods them, together with the resulting fry, for an extended period on the order of three to four weeks, feeding little or not at all during this time. She then releases free-swimming fry, typically into sheltered cover consistent with the species' cave-associated habits, with no further parental investment from either parent. Clutch size specific to this species is not documented here.
In the aquarium
Otopharynx spelaeotes is an uncommon aquarium fish outside specialist Malawi haplochromine circles. Given its apparent preference for cave and crevice shelter, an aquascape with generous rockwork offering multiple caves and overhangs, set over a sand substrate, would suit the species well, alongside a tank of at least 47–59 in to provide adequate territory. Water should follow the lake's chemistry — warm, hard, and alkaline, roughly pH 7.7 to 8.6. It can likely be combined with other moderately sized, non-overly-aggressive Malawi cichlids, though as with any Malawi species, adequate shelter and a mixed-sex grouping help reduce stress and aggression.
Conservation
No confirmed IUCN Red List status for Otopharynx spelaeotes is available here, so none is stated. As a species associated with specific rock and crevice habitats at particular sites, it would generally be exposed to the pressures common to that habitat type, including sedimentation that can fill and degrade rock crevices, shoreline development, and the broader fishing pressure documented across Lake Malawi, though a species-specific assessment is not confirmed in the sources consulted here.