Taxonomy & naming
Mugilogobius adeia was described by Larson & Kottelat (1992) and is listed as valid by the Catalog of Fishes, with the type locality east of Talu on the northern margin of Lake Matano. The species is a lake endemic, in a genus that elsewhere includes many estuarine and brackish-water gobies.
Morphology
A small, plain-looking goby with fused pelvic fins forming the usual sucker disc. FishBase gives a maximum of 1.5 in TL. Detailed colour has not been compiled in the sources used here.
Habitat
Lake Matano is a very deep, clear, oligotrophic lake in the Malili system with hard, alkaline water. FishBase lists the species as freshwater and demersal, known only from the lake, with a temperature range of 22 to 28 C. It stays close to the lake margins and was observed sheltering in empty shells of the snail Brotia gemmifera, which suggests a shell-dwelling habit.
Feeding
FishBase reports that it feeds on tiny short-spired gastropods. The genus is also noted as facultatively air-breathing.
Mating
Courtship and nest behaviour have not been described for this species.
Breeding
Breeding has not been described in the wild or in captivity.
In the aquarium
Husbandry has not been documented for this species. As a lake endemic from hard, alkaline, stable water, it should not be placed in soft acidic water, and the stability of its home lake argues for steady conditions. Empty snail shells are a sensible addition given its shelter habit in the wild.
Conservation
The IUCN lists Mugilogobius adeia as Endangered, meaning it faces a very high risk of extinction in the wild. The species is restricted to a single lake, which is a concern in itself, and the Malili lakes face pressure from introduced fishes, nickel mining and development in the catchment.