Alistair Clacherty looked out for the bluespotted ribbontail ray, Taeniura lymma, when he was on sabbatical in Zanzibar in the latter half of last year. In our Coastal Fishes of southern Africa book we mention that this ray may be a complex of 2 or 3 similar species. The holotype of the species was described from the Red Sea and the Red Sea specimens all have a blue line on either side of the tail. Specimens from southern Africa lack blue stripes on the tail. This colour difference might be due to sexual dimorphism or else they may be  different species . Alistair sent a photo of a blue-spotted ribbontail ray taken earlier last year off Jambiani, SE coast of Zanzibar, with no blue stripes on the tail.

The bluespotted ribbontail ray without blue tail stripes sent in by Alistair Clacherty from Zanzibar .

Reggie Lawrence took a photograph of a gurnard from False Bay. This is the species called  the bluefin

gurnard, Chelidonichthys kumu, in Smiths Sea Fishes. It was thought to be an Indo-West Pacific species but we now think that it might be one of a species complex (several similar species that have all been given the same name). The differences that were put down to variation due to locality might be differences between the species. This species was described from a New Zealand holotype. We were fortunate that Reggie also collected the specimen and kept it in his freezer. This means that we will also be able to compare the DNA of our’ kumu with those from Australia and New Zealand. These sedentary fish are good eating and are

commercially important. The free rays at the bottom of their large pectoral fins are used to find prey and also help the fish as it 'walks on the bottom'.

The bluefin gurnard, Chelidonichthys kumu. The photograph on the left was taken at Strandfontein, False Bay, by Reggie Lawrence. The photograph on the right is by Rudie Kuiter of a fish from southeastern Australia and can be seen in the World Atlas of Marine Fishes by Kuiter and Debelius, published by IKAN in 2006.

We also targeted species of fusiliers in 2006 - they have to be shot which is not the easiest thing to do as shoals are skittish and easily startled. Among the species collected were the three stripe fusilier, Pterocaesio trilineata and the twinstripe fusilier, Pterocaesio marri, at Sodwana Bay. These 2 species were first photographed at Sodwana by Dennis Polack and sent to us in 2005.

Copyright © 2007.

South African Institute for Aquatic Biodiversity (SAIAB)

Private Bag 1015

Grahamstown 6140.

 

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