Flabellina sp.1, with egg case.
Another Flabellina sp.1.
A different colour variation - is this maybe Flabellina sp.2?
A different colour variation - is this maybe Flabellina sp.2 as well?
Flabellina sp.1.
Detail of the rhinophores, showing their knobbly appearance.
All photos Guido Zsilavecz
This species, listed in Gosliner's nudibranch guide, is probably still undescribed. They were found on hydroids on the sea-ward side of Justin's caves. As the photos show, two colour variations were found: one pale yellow, another olive. In Gosliner's book two species are shown corresponding to this colour (the yellow one being species 1, the olive one species 2.), however, only species one is listed as having been found at Ouderkaal. It is thus not known whether the ones found are one or possibly both species. Both are listed as feeding on Eudendrium, a species of hydroid.
The top photo shows an individual with egg-ribbon, which is most likely that of this species. Interesting in this species are the rhinophores which seem knobbly - quite distinct.
There are two species of nudibranchs which superficially resemble this species: the olive nudibranch Facellina olivacea has a similar olive colouration, but a pink body, and cerata which are broader and much less pointed, apart from curving "inwards", whereas on Flabellina sp.1 they are straight. The Table Bay nudibranch Aplysiopsis sinusmensalis again has a similar colour, but lacks the clearly defined oral tentacles and rhinophores of this species.
The individuals shown were found on two different dives, although all in the same area. Maximum length was about 10mm.
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.