Thanks Mike,
It's always worth asking.
Best wishes,
Bill Rudman

Thanks Mike,
This photo certainly shows the white patches very well. From the close-up showing the white patches inside the gill circlet, it seems that they are glands - perhaps storing anti-feedant chemicals? 

Sorry to be choosey, but what I would really like is another photo of the green-spotted one in the mating pair in your first message to see if it has white patches as well. If it doesn't, it will suggest that the ones without white patches - which we identify as N. guttata, and the ones with white patches - which I have considered different, are probably all one species.

Best wishes,
Bill Rudman

Dear Mike,

Thanks for these photos. It is interesting that 'typical' N. guttata has this changing colour of the tubercles from red to green as well. I have always thought that this species was different from N. guttata - the tubercles seem smaller and there are always patches of white on the inside edge of each rhinophore and along the mantle edge of many individuals. However in your photo alongside, of the two mating, the green spotted animal seems to lack the white markings, and so looks as though it is N. guttata. If this is so, then what I have been separating off as Nembrotha cf. guttata may just be a juvenile form of N. guttata. You may have recorded an interesting observation here - certainly something anyone revising this group should keep in mind in the future.

In the photo alongside, the two mating animals are sitting on a large ascidian. Species of Nembrotha feed on ascidians so it is possible this is there food.

Best wishes,
Bill Rudman

Note added 29 Jan. 2002: On the arrival of more photos I don't think this colour form is Nembrotha guttata. - Bill Rudman

Dear Erwin,
This one seems to show light greenish lines on the inside edges of the gills.
Best wishes,
Bill Rudman

Note added 29 Jan. 2002: On the arrival of more photos I don't think this colour form is Nembrotha guttata. - Bill Rudman

Dear Erwin,
Thanks for these photos. They greatly help to clarify at least one of these red-spotted species. I am pretty sure this is the species described by Nathalie Yonow from the Maldives as Nembrotha guttata. This species was described from a single animal so it is fortunate that you have provided a number of photos showing enough colour variation to allow us to match this varaible animals with her description.

Basically the animal is black with scattered orange pustules. Yonow says that about 30% od the orange pustules are edged in green. This does not seem to be the case in your photos but in one animal (ek128001) a few green pustules are visible. The biggest difference concerns the rhinophores and their pockets. Yonow describes the rhinophores as black with orange dusting on the anterior sides of the lamellae. While ek127204 shows signs of orange dusting on the lamellae there is a variation from complete black to a pale almost white dusting. She describes the rhinophore pockest as black with an orange edge. Traces of this orange edge can be seen in ek128001, but in ek127204 it appears translucent green, and in others the whole sheath is heavily dusted in white. No mention is made of the white patch at the base of each rhinophore pocket which occurs in all your photos except ek125401.

This is a good example of how dangerous it is to name new species on a single animal.

I think that the animals in three previous messages message 1 message 2 message 3, can be transferred from the "Red-spotted page" to N. guttata. The other 'species' we have to consider is the one I have identified as an orange-tinged Nembrotha cristata. I wondered whether this was a link between N. cristata and N. guttata but apart from the general shape, I think the gill colouration in N. cristata, with light green on the outer edge, is probably a unique character of N. cristata.
Best wishes,
Bill Rudman

Dear Kim,
Your photo is certainly the same as one of the animals I have 'lumped' as Nembrotha spp. I am not sure if there are one, two or three species here. Yours looks like the one in the bottom left photo. There is another photo in Erwin Koehler's message from the Philippines, and in another message from Japan by Rie Nakano.

We would need to check the anatomy of the three 'species'/'colour forms' to say anything sensible.

Species of Nembrotha eat ascidians (sea squirts), usually colonial species, and most seem to have a fairly specialised diet eating only one or a very few species of ascidian. One possibly useful observation that divers could make if they find a Nembrotha on an ascidian, to take a photo. Although being 'on' something doesn't necessarily mean you are eating it. Enough photos could suggest a pattern which would be worth following up. If you look at the Erwin Koehler's photo of one of the three 'species' it seems to be feeding on a green ascidian. If the other we could get more photos of that colour form on the same ascidian, and photos of the others on different ascidians then that would certainly indicate they were probably different.
Bill Rudman.

Dear Rie,
Thanks for the photo. I think there are two or three different species on the Nembrotha spp page. I have put them together so it was easier to compare them. Hopefully one day we will be able to give them separate pages, when someone shows us they are distinctly different from each other.

Your photo looks like the one on the bottom left of the page. (See Erwin Koehler's message for other photos). Any information on what your animal eats or the shape and colour of the egg mass, or photos, would be useful. If we can get similar information for the other 'species' or 'colour forms' it might help show whether they are different species.

Best wishes,
Bill Rudman.

Erwin,
It's probably different from the other two [red spotted ones] but I've kept them together for comparison.
Bill Rudman.