Oreochromis rukwaensis (Hilgendorf & Pappenheim, 1903)
Description
Dorsal spines (total): 15 - 17; Dorsal soft rays (total): 11 - 13; Anal spines: 3; Anal soft rays: 10 - 11; Vertebrae: 30. Diagnosis: Typical tilapiine cichlid, relatively deep bodied, with rather a small head (Ref. 118638). Other distinguishing characters are: caudal fin free of scales except basally; vertebrae 30; scales in lateral line series 30-32; dorsal spines XV-XVII; soft rays usually 11-13; outer teeth bicuspid, in mature fishes occasionally with a few tricuspids; lower gill-rakers 20-22; interorbital region in adults 34.5-40.0% length of head (Ref. 2). Ripe males have a dark body and fins, almost black, with bright red/orange margins on the dorsal and caudal fins; vertical barring can be noticeable in freshly caught specimens; head region in ripe males has a bluish sheen; ripe males have yellow-orange tassels; females and subadult males plain silver/grey with 6-7 post-opercular vertical stripes and bluish snout present in freshly caught specimens (Ref. 118638).
Common Names
No common names available.
Taxonomic Hierarchy
Kingdom: Animalia
Phylum: Chordata
Class: Teleostei
Order: Cichliformes
Family: Cichlidae
Genus: Oreochromis
Species: Oreochromis rukwaensis (Hilgendorf & Pappenheim, 1903)
Climate Zone
Location
Biology
This species is found both in large lakes and small rivers (Ref. 4967, 118638). A maternal mouthbrooder (Ref. 118638). Males construct territories in shallow water; where there was ample space they were similar in structure and grouping to those of Oreochromis variabilis, each territory consisting of a central raised mating platform in the middle of a large circular depression (Ref. 2). It is a major component of the fisheries catch in Lake Rukwa and the Mtera Dam (Ref. 118638). Strong aquaculture potential given broad habitat requirements (Ref. 118638). IUCN conservation status is stated as vulnerable D2, declining population trend (Ref. 118638).
Habitat
benthopelagic