Taxonomy & naming
Chindongo cyaneus belongs to Chindongo, a genus of small mbuna erected in 2016 by Shan Li, Ad Konings, and Jay R. Stauffer Jr. in a revision of the former Pseudotropheus elongatus species group (published in Zootaxa), which transferred ten species — including the well-known Chindongo demasoni and Chindongo saulosi — out of Pseudotropheus and into the new genus. Chindongo is diagnosed by bicuspid teeth in the front tooth rows of both jaws, a small mouth, and a flank pattern of vertical bars rather than the longitudinal spotted bands of Pseudotropheus proper. Eschmeyer's Catalog of Fishes is the reference for this species' currently accepted describing authority and date, not restated here to avoid an inaccurate citation. The epithet cyaneus derives from the Greek kyanos via Latin, meaning "dark blue" — the same root that gives English "cyan" — almost certainly describing the fish's blue body colouration.
Morphology
Chindongo cyaneus follows the small, elongate, laterally compressed mbuna body plan shared across the genus. Its defining feature, encoded in the name, is a blue body colour, plausibly set off with the vertical dark bars typical of Chindongo. Precise published measurements are not confidently known here; other Chindongo species typically run 2.5–3.5 in total length as small mbuna. Sexual dichromatism in the genus is variable — some species, like C. demasoni, are essentially monomorphic, while others show clear male/female colour contrast — and it is not confirmed here which pattern applies to C. cyaneus.
Habitat
The species is documented from Chinyamwezi Island, a small island in the southern part of Lake Malawi near the Nankumba Peninsula. Like all Chindongo and mbuna generally, it is confined to the shallow rocky littoral zone, where extensive boulder fields and reef structure sustain the algal growth mbuna depend on. Water conditions there follow the standard Lake Malawi profile — warm, hard, and strongly alkaline, broadly in the mid-20s Celsius with a pH on the alkaline side of neutral, typically in shallow-to-moderate depths.
Feeding
As a Chindongo, this species is expected to be an aufwuchs grazer, biting algae, diatoms, and cyanobacteria from rock surfaces — the defining feeding strategy of the mbuna as a whole, and one the genus diagnosis specifically links to a biting rather than combing feeding action. No species-specific dietary study for C. cyaneus is documented here, so this account reflects the general feeding ecology of the genus rather than a confirmed study of this particular species.
Mating
Reproduction is expected to follow the polygynous, non-pair-bonding pattern typical of mbuna: territorial males hold and defend a patch of rock and display to attract females, which move between males rather than forming lasting bonds. Whether C. cyaneus shows the strongly territorial courtship typical of most mbuna, or the more relaxed pattern documented for its congener C. demasoni, is not known here; this account reflects the general breeding biology of the genus rather than direct observation of this species.
Breeding
Chindongo cyaneus is presumed to be a maternal mouthbrooder, as are all Chindongo and mbuna generally. After spawning at a male's rocky territory, the female takes the fertilised eggs into her mouth and broods them alone, typically for a few weeks, before releasing free-swimming fry with no further parental care from the male. Clutch size and brooding duration are not documented for this species specifically; comparably sized dwarf mbuna typically produce clutches of a few dozen eggs.
In the aquarium
Chindongo cyaneus does not have a well-documented presence in the aquarium hobby; specific keeping notes are not available here. Husbandry would be expected to follow the standard template shared by its better-known relatives such as C. demasoni: dense rockwork to break sightlines and diffuse aggression, hard alkaline water buffered into the high 7s to high 8s pH range, and a diet centred on spirulina- or algae-based foods rather than protein-rich fare, which is linked to bloat in mbuna. Group size management (either a single specimen or a crowd, avoiding small groups) is the standard mbuna approach to intraspecific aggression.
Conservation
No confident IUCN Red List status is available for Chindongo cyaneus and none is asserted here. As a rock-dwelling mbuna documented from a single southern-lake island, it would potentially have a restricted range and would be exposed to the general pressures affecting Lake Malawi's littoral reef habitat — ornamental collection, inshore sedimentation, and cumulative fishing pressure — but no formal population assessment is documented in the sources consulted for this article.