Photo by Andrew Taylor
Nudibranchs are often hard to identify - many are superficially similar and require much work under a microscope to identify correctly. It is thus not uncommon for nudibranchs to be shifted from species to species and even from genus to genus. Gosliner listed this nudibranch as P. serratum, described by Baba in 1949, but this was later revised as it was found that it was P. horridus, described by Macnae in 1954, instead.
Nudibranchs of Southern Africa - a guide to the opisthobranch molluscs of southern Africa, T Gosliner, 1987.
Australian nudibranch news, No.3, November 1998.