Dear Stu,

I discuss the animal in your upper photo in message #21144 and this group of reddish spotted species more generally on the Nembrotha spp Fact Sheet.

I am pretty sure these two are different species. I am afraid we can't say much more about them at present.

Best wishes,
Bill Rudman

Thanks Ken,
I can't see a quick answer for this group, but every new photo helps to clarify the range of variation.

Best wishes,
Bill Rudman

Dear David,

I knew I had seen a sphoto of an animal like Colin's recently. Yes this well illustrates my point that we still have a few things to sort out with these animals with reddish spots. For consistency I'll move his message to the Nembrotha spppage

Best wishes,
Bill Rudman

Dear Colin,

I think this is probably N. livingstonei although I woud normally expect to see a  white cross between the rhinophores, or some traces of one. Perhaps in the western Indian Ocean that part of the colour pattern is lost. I think we still have a bit to do in sorting out the red-spotted species so keep your eyes out for other variations.

Concerning species changing food as they develop. Once a species settles from the plankton they begin feeding on their adult food. In many cases it is chemicals from the adult food which trigger the settlement behaviour in the swimming planktonic larvae. Obviously in species where the adults eat whole polyps, the juveniles can't do the same, but they seem to eat other parts of the colony, rather than a different food. In species of Nembrotha we would expect them to eat one or more ascidians.

Best wishes,
Bill Rudman

Dear David,

My best answer to your question about whether I can identify this animal is 'yes and no'. If you look at the Nembrotha spp page you will see a group of reddish spotted animals I haven't been able to put a name on, and many of them [see #19534], but not all of them, seem to be the same species as yours. I have kept them separate from the ones I have identified as Nembrotha guttata. But I am not even sure about that species and have some separated as Nembrotha cf. guttata. Some animals have a distinct orange cap to the rhinophore club and an orange margin around the rhinophore sheath while others don't. Some, like yours, have white rhinophore sheaths and white edging to the gills etc etc.

I am afraid I don't think the recent Nembrotha paper (Pola et al, 2008) has resolved this problem and as they say in their discussion "the internal anatomy of the species complex nigerrima-cristata-yonowae is very similar" so we are apparently not likely to find a simple answer in the basic anatomy.

To complicate matters there is also a nomenclatural problem - that is a question about what names we should use as well as how many species there are and how we should identify them. Pola et al, propose we replace Nembrotha guttata Yonow, 1993 with N. yonowae Goethel & Debelius, 1992 considering them both to be the same. When Yonow described her species she deliberately stated that the description of N. yonowae was so poor, and lacked a type specimen, and so was unable to be distinguished from other red-spotted species. Even if at that time the International Code did not require there to be a type specimen deposited, if there is no available specimen how do you check to see just which red-spotted species they were describing? As you can see here, there are probably more than one species involved. So on those grounds she described her species as distinct. In Pola et al there are three colour photos identified as N. yonowae, one of which (Fig 14A) looks like what I am calling N. guttata, but the other two (Fig 14B,C) look more like your animal. They also have another photo (Fig 14 D) of a red-spotted animal which they identify as Nembrotha sp. and which looks like others on my miscellaneous red-spotted page. I mention this because it suggests the author's are not clear themselves on just what constitutes what they call Nembrotha yonowae. If that is the case it seems premature to synonymise that name and N. guttata as they might both turn out to be valid species.

At the moment I am trying to get a copy of the Goethel & Debelius description of N. yonowae. It was published in a non-scientific journal and I have until now been unable to find a copy. So basically I can't identify your animal at present. As Pola et. al say "further morphological and molecular studies need to be done to fully resolve these issues"

• Pola, M., Cervera, J.L. and Gosliner, T.M. 2008. Revision of the Indo-Pacific genus Nembrotha (Nudibranchia: Dorididae: Polyceridae), with description of two new species. Scientia Marina 72(1): 145-183.

Best wishes,
Bill Rudman

Dear Brian,

Yes it certainly looks the same. There still seems to be some work needed on these red-spotted nembrothids.

Best wishes,
Bill Rudman

Dear Joy,
I guess this is one we are not going to be able to answer.

Best wishes,
Bill Rudman

Dear Joy,
This is unnamed species of Nembrotha which I am clustering with a number of similarly coloured  red/orange-spotted species. Yours is almost certainly the one in  a recent message [#18238] which has 3 large branched gills. Your animal, apparently with only 2 gills, is either damaged, or one of its gills is obscured in your photo.

Best wishes,
Bill Rudman

Dear Ugo,
Thanks very much. This is clearly the same animal as Erwin Koehler's photographed earlier [message #441]. From the shape of the gills it is definitely not a colour form of Roboastra gracilis.

Best wishes,
Bill Rudman

Dear Gareth,
This is another interesting find. Almost certainly a tropical visitor. I am afraid these reddish spotted polycerids are a bit of a mess to idntify at present. Your animal look very like one in Stuart Hutchison's photos from Papua New Guinea. So if you want a label for it I am afraid 'polycerid sp' might be as far as I am willing to go at present.
Best wishes,
Bill Rudman

Dear Kirk,
I am not sure whether this is a species of Nembrotha or not. There appear to be a number of similarly coloured species which need sorting out. I have placed them together on a red-spotted Nembrotha page.
Best wishes,
Bill Rudman

Dear Stuart,
These are almost certainly juveniles. They are one of a group of orange-spotted nembrothid species I have grouped on one page more for convenience than belief they are a single species. I suspect your animals are most like the Top Right photo at the Top of the Page.

We will need some animals to look at before they can be sorted out.

Best wishes,
Bill Rudman.

Erwin,
It seems to be feeding on the blue-green ascidian it is sitting on. Concerning identification - have a look at my comment at the top of the page.
Bill Rudman

Erwin,
This is probably a third species.
Bill Rudman.