The tan nudibranch (Doriopsilla capensis)
Photo Wilhelm van Zyl
Another one, looking more tan this time.
Photo Guido Zsilavecz
Mandela's nudibranch (Mandelia mirocornata)
Photo Wilhelm van Zyl
Another one.
Photo Guido Zsilavecz
Detail, showing the rhinophores.
Photo Guido Zsilavecz
The tan nudibranch, Doriopsilla capensis, is a very plain, white to tan nudibranch with a pale margin and a slightly rough dorsal surface. It is often seen as a circular small blow, gills withdrawn, on overgrown reef walls further offshore. Only occasionally does one see it stretched out crawling over the reefs. Because of this it is easy to overlook it. It is quite small, reaching at most 3 cm in length. I have yet to see it in False Bay, and have seen it most often at deeper Oudekraal, Coral Gardens and the deeper dive sites off the Hout Bay Sentinel.
Mandela's nudibranch, Mandelia mirocornata, named in Mandela's honour by its describer, Terry Gosliner, is a common sight at Coral Gardens, but can be found at most deeper Atlantic sites, on rocky reef walls. The body is rough-skinned, with a pale cream to yellow colour and overlaid with darker irregular spots, of different sizes. Gosliner placed it in its own genus because of the unusual rhinophores, which are indeed different as the close-up shows. It attains at least 5 cm.
Nudibranchs of Southern Africa - a guide to the opisthobranch molluscs of southern Africa, T Gosliner, 1987.