Fish Identification

Submit any queries with regard to fish identification. Prof. Skelton, Denis Tweddle and Dr. Clinton Hay will assist us with the id of fish.  

1. Dusky bream...?

26 August 2013
Mauro Rosa from the Crockango Angling Club requested (sms) information on the "Dusky bream" as there is no description of it in prof. Skelton's book, "Fishes of Southern Africa"....?

Response from Denis Tweddle:

Sargochromis species in Upper Zambezi, Namibia
There are four species of smallmouth breams, Sargochromis species, in the Upper Zambezi River. Two of these are believed to be definitively identified. These two are the pink bream, Sargochromis giardi, and the rainbow bream, Sargochromis carlottae.
The third species, a smaller, less deep bodied species was thought to be the green bream, Sargochromis codringtonii, while a fourth species was confused with the pink bream until very recently.
Because of its darker overall colouration, the name ‘dusky bream’ was suggested for this latter species. In referring back to the original descriptions instead of relying on the revision by Bell-Cross in 1975, it has now been realised that the dusky bream is in fact almost certainly S. codringtonii. Note the very close similarity between the photograph of the juvenile and the illustration of the type of S. codringtonii  below.
This now means that the green bream needs to be correctly identified. It is unlikely to be either of the species that most closely resemble it in the 1975 paper by Bell-Cross, i.e. S. mortimeri, which was described from the Upper Kafue River, or S. greenwoodi. Both are illustrated below  
Sargochromis giardi, pink bream, Upper Zambezi River, male breeding colouration.
Sargochromis giardi, pink bream, Kafue specimen, Bell-Cross (1975)

Dusky bream, juvenile
Dusky bream, adult male

Green bream,  Upper Zambezi, Liuwa National Park
Photo in Bell-Cross (1975), incorrectly identified as S. codringtonii
Green bream,  Upper Zambezi, breeding male, Lake Liambezi

S. greenwoodi holotype (Boulenger = S. frederici)
Sargochromis carlottae, Upper Zambezi

S. greenwoodi photo in Bell-Cross (1975), locality not stated

Sargochromis carlottae Bell-Cross (1975), Upper Zambezi
Sargochromis mortimeri  holotype,  Bell-Cross (1975), Mwekera-Kafue
S. carlottae according to Bell-Cross (1975), Kafue (definitely not carlottae!)

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