Oreochromis shiranus Boulenger, 1897
Description
Dorsal spines (total): 15 - 18; Dorsal soft rays (total): 10 - 13; Anal spines: 3 - 5; Anal soft rays: 9 - 11; Vertebrae: 29 - 30. Diagnosis: A large, deep-bodied species with 4, rarely 3 or 5, anal fin spines (Ref. 118638). Females and immatures from the Lake Malawi catchment have a dark olive-coloured body, yellow-gold below; other populations, such as those from Lakes Chilwa and Chiuta and the Ruvuma system show a more silvery colour; unusually for Oreochromis, the horizontal stripes are often more prominent than the vertical bars; adult males develop very large jaws and a concave head profile, they are black, with red margins to the dorsal and caudal fins (Ref. 118638). Underwater or in aquaria, males show numerous white spots on the upper half of the flanks, but these fade quickly under stress, so that they appear uniformly black when removed from the water (Ref. 118638).
Common Names
No common names available.
Taxonomic Hierarchy
Kingdom: Animalia
Phylum: Chordata
Class: Teleostei
Order: Cichliformes
Family: Cichlidae
Genus: Oreochromis
Species: Oreochromis shiranus Boulenger, 1897
Climate Zone
Location
Biology
Found in very shallow waters around Lake Malawi that are densely vegetated, but also in lagoons (Ref. 5595). It can occur at temperatures ranging from 23.0-42.0 °C (Ref. 670). It feeds on detritus and phytoplankton (Ref. 5595). A maternal mouthbrooder (Ref. 118638). A large species heavily exploited in Lake Nyasa [= Lake Malawi] and its catchment; males in particular are fast-growing and the species is cultured commercially in Malawi in cages and ponds (Ref. 118638).
Habitat
brackish