Janolus capensis? from S Africa

Dear Rudolph,
The animals in your photos are both species of Janolus, part of a family of nudibranchs which feed on bryozoans. There are two very similarly looking species from South Africa, Janolus capensis and Janolus longidentatus. I am not sure which species these are, or if both photos are of the same species. There are good anatomical differences between the species, and their egg masses are quite different, but unfortunately there general appearance is very similar. Gosliner does say that in J. capensis the anterior end of the head is conical, while in J. longidentatus it is rounded, but unfortunately this can't be see in your photos.

In your upper photo the brown ducts of the digestive gland seem to branch near the base, which is what happens in J. longidentatus, and in the lower photo the crest between the rhinophores is white, which is what has been described for J. capensis, so it is possible that you have both species here, because they are both recorded to feed on the bryozoan Menipea. At this stage I am not sure of the identity of the other photos on this page either, but have decided to leave them all as J. capensis.
Best wishes,
Bill Rudman