Colour variant of Trapania aurata?

October 4, 2002
From: Heike Waegele

Dear Bill,
Here is a Trapania, which does not seem to be a Trapania aurata, according to your former notes in the Seaslug Forum. Michael Miller seems to have found similar specimens on Bali some years ago, but his specimens had orange markings on the foot. My specimen from Lizard Island did not have this line on the foot. And it has not the markings on the ceratal processes (gills and rhinophores) as your T. aurata. On the other side, there seems to be a certain variability in the colour stripes on the gills. Some T. aurata specimens seem to have the colour stripes, some not. My specimen had a similar colour to Michael ones: the markings were
more orange brown and not golden yellow. Maybe that all the animals belong to one species with a certain degree of varying colour markings?

Waegele, H., 2002 (Oct 4) Colour variant of Trapania aurata?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear Heike,
Thanks for the message. As you say, your animals have similarities and differences to 'typical' T. aurata. The species was based on Hong Kong specimens so the photos of that specimenm can be considered 'typical'. The animals from New Caledonia show that the presence of orange/yellow on the gills is variable. It also differs from Hong Kong animals in the colour of the oral tentacles and of the head, In Hong Kong animals the oral tentacles are orange and they are connected by a band of orange bordering the front of the head. In New Caledonian animals there is a basal white band on the oral tentacles and no orange band across the fromt of the head. However the radular morphology, which usually is quite distinctively different in different species, shows little difference between Hong Kong and New Caledonian animals.

I am not sure whether your animals and Mike's from Bali are part of the species' colour variation or not. To save them from getting lost on the 'true' T. aurata page I have put them on a Trapania cf. aurata Page until we know more about them.
Best wishes,
Bill Rudman

Rudman, W.B., 2002 (Oct 4). Comment on Colour variant of Trapania aurata? by Heike Waegele. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from