Actinopteri (ray-finned fishes) > Cichliformes
(Cichlids, convict blennies) > Cichlidae
(Cichlids) > Pseudocrenilabrinae
Etymology: Oreochromis: Latin, aurum = gold + Greek, chromis = a fish, perhaps a perch (Ref. 45335).
More on author: Hilgendorf.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic. Tropical; 2°S - 3°S
Africa: known only from the catchment of Lake Natron, Tanzania and Kenya (Ref. 2, 5166, 118638).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 11.6 cm TL male/unsexed; (Ref. 32272)
(total): 9 - 13;
soft rays: 9 - 11;
Vertebrae: 27 - 30. Diagnosis: A small elongated species with a terminal mouth (Ref. 118638). Mature males have dark-edged dorsal and anal fins, iridescent blue-white spots on flanks, white lower lips, and a spotted caudal fin with a pink edge; they appear to be colour polymorphic, with some males having yellow bellies and throats, while others are blue white: both morphs can be found in the same location and the colours are stable in aquarium-held specimens, suggesting it is a true polymorphism and not related to reproductive state (Ref. 118638). Females and non-territorial males are sandy-coloured, pale ventrally, sometimes with faint vertical bars (Ref. 118638).
Occurs at a temperature range of 30-32°C (Ref. 2). It feeds actively in the early morning; mainly on algae as well as copepods and dipterous larvae (Ref. 2). A maternal mouthbrooder: males excavate pits in the substrate in shallow water (Ref. 2, 118638). The species is occasionally caught as a food fish in its natural range; although it attains a small size, its tolerance of hostile environments may make it suitable for culture in high salinity environments; potential as an aquarium fish (Ref. 118638). Classed as endangered, due to its restricted distribution (Ref. 118638).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Early in the morning before taking possession of their pits, the males feed on slimy algal growths-noisily; sexual activity is greater after noon than before; young male may build a small pit around that of a larger male and mate there with a small female (Ref. 2). Males prepare and guard nests, while females migrate from one nest to another; males guard the nest against juveniles of their own species and other species which feed on the fertilized eggs which fall from the mouth of the female mouth brooder (Ref. 11288). Also Ref. 118638.
Seegers, L. and H. Tichy, 1999. The Oreochromis alcalicus flock (Teleostei: Cichlidae) from lakes Natron and Magadi, Tanzania and Kenya, with descriptions of two new species. Ichthyol. Explor. Freshwat. 10(2):97-146. (Ref. 32272)
IUCN Red List Status (Ref. 125652)
Endangered (EN) (B1ab(i,ii,iii)+2ab(i,ii,iii)); Date assessed: 31 January 2006
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82804
= 0.5625 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01905 (0.00846 - 0.04293), b=3.01 (2.82 - 3.20), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 2.7 ±0.21 se; based on food items.
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Fishing Vulnerability (Ref. 59153
): Low vulnerability (10 of 100).