modern times
Jim Cambray
WHEN an Eastern Cape farmer saw some small fish in his streams, he thought they were trout spawning, and called in local scientists to make sure. They discovered the little creature was, in fact, the Cape galaxias, which had never before been recorded in Eastern Cape river systems.
Also known as Galaxias zebratus, this striped fish, not much longer than an adult’s finger, was originally described from the Cape Flats by the French Count Castelnau in 1861. Since then it has been recorded in a number of coastal rivers, from the Keurbooms to the Olifants River system in the Cape.
Although it has many relatives in the southern hemisphere, it is the only species in Africa. The Galaxiidae are secretive fishes, which quickly dart under rocks if threatened,and can exist in large numbers undetected. Galaxias zebratus went undetected in both the Krom and Gamtoos river systems until recently.
The long, slender bodies of young fish make them easy to distinguish from other small fish such as minnows. The larger mature fish are more difficult to observe and stay on the bottom, under rocks or in vegetation. Their bodies are transparent, with red gills.
When the males are ready to breed, you can see their milt through the body walls. Likewise, the relatively large eggs can be seen in the females.
This unusual little fish has been in Africa for possibly 100-million years and is part of the unique biodiversity of South Africa. Alien fish species could eliminate remaining populations within a year. It is time to seriously consider how to conserve them.
Dr Jim Cambray is a specialist scientist in the department of freshwater ichthyology at the Albany Museum in Grahamstown