Siphopteron alboaurantium
Spiky dorid
Spiky dorid close-up, showing the bumps on the dorsal surface
Chocolate-chip dorid
Chocolate-chip dorid closeup, showing the smooth dorsal surface
Wide-ridged nubibranch in unusual bright colours, found at Tafelberg reef
Photo Peter Southwood
Two wide-ridged nubibranch in the more normal, muted colours
An unusual pink wide-ridged nubibranch
Another Melibe liltvedi
Except for purple wide-ridged nudibranch, all other photos Guido Zsilavecz
Tafelberg reef is situated in line with Vulcan rock, off the Hout Bay sentinel, but about 1/3 the way to Chapman's peak. The main reef is a solid square block - hence the name "table mountain" - which drops off into deeper water all around it quite quickly. A very torn apart wreck of a yacht marks the site.
During a few dives at the reef SURG members found a number of unusual and interesting nudibranchs.
Siphopteron alboaurantium
This unusual species, described in 1984 by Dr. Terry Gosliner, and placed in the genus Gastropteron, is only found in depths of more than 20m, on rocky reefs. It can swim by flapping its parapodia. This species has not been consciously seen since its description! Length was about 5mm.
Spiky dorid Aphelodoris sp.3
These dorids have been found before at similar reefs, especially on those off shore from Maori Bay, but have not been seen in over a year. At Tafelberg they were found to be common in some areas. This dorid takes its name from the spiky or bumpy appearance of its dorsal surface, as shown in the closeup. It is not sure if this a different species, or whether they are just simply Chocolate-chip dorids (Aphelodoris sp.1) with a temporarily bumped-up notum. As can be seen from the photos, both species are similar at a glance.
Wide-ridged nudibranch Dermatobranchus sp.
The wide-ridged nudibranch is a small, inconspicuous nudibranch found on most deeper Atlantic dive sites. The colour is usually white with brighter white ridges, with the white ranging from a light blue to a creamy colour. A pink speciment has been seen, as shown, but the intense colour of the specimen found at Tafelberg is quite unusual. It is probably only a colour variant, however, and not a new species.
Dinosaur nudibranch Melibe liltvedi sp.
After many years of not having been seen, we are now seeing more of these nudibranchs!
For more details on some of these species, see "Nudibranchs of the Cape Peninsula and False Bay", now available from SURG and better Cape Town dive shops.
Thanks to Dr. Terry Gosliner of the California Academy of Sciences for information.
Nudibranchs of the Cape Peninsula and False Bay, G. Zsilavecz, 2007.
Nudibranchs of Southern Africa - a guide to the opisthobranch molluscs of southern Africa, T Gosliner, 1987.