The Biology and Culture of Tilapias

B- Subgen. Oreochromis

N! Subgen. Nyasalapia

o S. xhwebischi

SADanakilia) franchettii

Figure 2. Natural distribution of the subgenera Oreochromis (////) and Nyasalapia (\\).
Q S. schwebischi (Sauvage), of uncertain subgeneric affinity and S. (Dcmakilia) Fan-
chettii (Vinciguerra). (Trewavas, in press).

Sarotherodon Species and Fish Culture

S. galilaeus is the only species of subgenus Sarotherodon that has been

used for fish culture. It has not been favored for ponds, mainly, I think,

because of its slower growth, but it is (or was) so used in Cameroon, the

stock being mainly &om the Chad basin, but also &om R. Sanaga, the latter

perhaps a distinct subspecies. Moreover S. galilaeus has done well in man-

made lakes and reservoirs in open water.

The other well-known cultured species are members of subgen. Oreo-

chromis and the tasselled species, Nyasalapia. The familiar names are S. nib-

ticus with seven subspecies, of which three have been cultured experimentally

by huginin et al. (1975); S. aureus, which accompanies S.n. niloticus through