| Ref. principal | Trewavas, E., 1983 |
| Aparência refere-se a | macho; fêmea |
| Bones in OsteoBase |
| órgãos especializados | genital papilla with tassels (m) |
| aparência diferente | different morphology during breeding season only |
| cores diferentes | different colors during breeding season only |
| Notas | Male with bifid white genital tassel (Ref.4967); with blue or white head while female/juvenile silver grey (Ref. 6150). Ripe testes broad, white & sinuous. |
| Características determinantes | none |
| Forma lateral do corpo | fusiform / normal |
| Secção transversal | compressed |
| Perfil dorsal da cabeça | more or less straight |
| Tipo de olhos | more or less normal |
| Tipo de boca/focinho | more or less normal |
| Posição da boca | terminal |
| Type of scales | cycloid scales |
| Diagnose |
Diagnosis: A heavily-built large tilapia species with a wide rounded head; dwarf populations exist in some crater lakes, showing bony 'hunger-form' body shape (Ref. 118638). Females and juveniles with grey bodies and 6 or more vertical bars; males have a bright blue, occasionally white or green, 'mask' across the head; when fully ripe, the underside of most of the body can be black, with the upper surface a conspicuous white to pale blue; genital tassel can be long and branched, pinkish to bright yellow; females and non-territorial males are indistinguishable from Oreochromis karongae (Ref. 118638). Description: Length of head35.7-38.0% of standard length; lower pharyngeal toothed area with concave sides; median length of bone 1.26-1.36 times its width and 37.6-40.6% length of head; blade 1.6-2.4 times the median length of the toothed area; length of lower jaw 31.4-34.0% length of head; teeth of jaws in 3-5 rows (Ref. 2). Colouration: Breeding male silvery blue with white and pale blue top of head and dorsum and white dorsal margin (Ref. 2). |
| Facilidade de identificação |
| Linhas laterais | 2 interrompido: No |
| Escamas na linha lateral | 32 - 35 |
| Escamas da linha lateral com poros | |
| Escamas em séries laterais | |
| Fileiras de escamas acima da linha lateral | |
| Fileiras de escamas abaixo da linha lateral | |
| Escamas em torno do pedúnculo caudal | |
| Barbilhões | 0 |
| Fissuras branquiais (tubarões/raias apenas) | absent |
| Raios branquiais | |
| no membro inferior | 17 - 22 |
| no membro superior | 2 - 4 |
| total | |
| Vértebras | |
| Pré-anal | |
| total |
| Atributos | extending over most of the back length |
| Número de barbatanas | 1 |
| No. de pínulas | Dorsal |
| Ventral | |
| Total de espinhos | 16 - 17 |
| Total de raios moles | 10 - 11 |
| Barbatana adiposa | absent |
| Atributos | more or less truncate; more or less normal |
| Número de barbatanas | 1 |
| Total de espinhos | 3 - 3 |
| Total de raios moles | 8 - 10 |
| Peitoral | Atributos more or less normal |
| espinhos | |
| Raios moles | |
| Pélvica | Atributos more or less normal |
| posição thoracic beneath origin of D1 | |
| espinhos | |
| Raios moles |