October 10, 2003
From: Adam Petrusek
Thanks for the identification of Cyerce graeca.
Here are some more photos of this Croatian specimen of Cyerce graeca. Although there is nowhere in the photos where the dorsal part of the animal is really well visible (the cerata are somehow in the way...) I think we can be sure that it is dark pigmented. I will almost certainly manage to obtain more photographs in time, if there are more details to be seen, I will post them.
This specimen was caught by a diver during the Mediterranean Marine Fauna excursion of the Charles University in Prague (Czech Republic). The photos are taken in the aquarium. Date: September 7, 2003. Photographer: Martin Cerny. I will try to get more exact data about the locality, which was off Brac Island, Adriatic sea, Croatia.
I have one question regarding the taxonomy of Cyerce. I have found three different assignments to the family: HERMAEIDAE Adams H. & A., 1854; CALIPHYLLIDAE Thiele, 1912; POLYBRANCHIIDAE O'Donoghue, 1929.
How well are these families supported?
Bill, thank you very much, for your excellent and at least for us, very important work!
Petrusek, A,, 2003 (Oct 10) Re: Cyerce graeca from Croatia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11183
Thanks for these extra photos. I have included some close-ups to show the colour and shape of the cerata. The white specks are small glands, probably defensive. In this species they seem to form a band at the tip of each ceras. You can also see in the photo of the animal crawling upside down a pair of rhinophoral head tentacles. In this family the rhinophores are divided so there are in fact two on each side. In this case you can see the two right rhinophores.
Concerning a Family placement. There is been quite a few exhaustive studies on the sacoglossans over recent years and the relationships of genera and famileis are beginning to be somewhat more stabilisd than in the past. Without going in to great detail, of the 3 family names you mention here, 2 [Caliphyllidae, Polybranchiidae] are essentially a nomenclatural problem since both refer to the same evolutionary branch or clade, and the Hermaeidae represent a similar-looking but quite distinct clade. Present usage accepts the Caliphyllidae as the correct family name.