Petalifera cf. ramosa  Baba, 1959

Click the thumbnail photos to enhance!

cf. is an abbreviation from a Latin word (confer) and means 'refer to' or 'compare with', here it means it could possibly be Petalifera ramosa or perhaps something closely related, or at least similar in appearance.
Petalifera cf. ramosa is characterized by a green body colour with minute brownish spots, and white branched papillae. There are also papillae on the rhinophores and on the oral tentacles.
It is Petalifera cf. edmundsi (Bebbington, 1974) in IPN at page 61:
Gosliner, Terrence M., David W. Behrens & Ángel Valdés. 2008. Indo-Pacific Nudibranchs and Sea Slugs. Sea Challengers Natural History Books.
Gig Harbor, Washington. 426 pp.
All I can find on Petalifera edmundsi at the web is: it was originally placed by Bebbington in the genus Phyllaplysia, published in:
BEBBINGTON, A. (1974), Aplysiid species from East Africa with notes on the Indian Ocean Anaspidea (Gastropoda: Opisthobranchia). Zoological Journal of the Linnean Society, 54: 63–99. doi: 10.1111/j.1096-3642.1974.tb00793.x
There is no picture nor decription of it for free, so I can't tell how it differs, and I don't know who moved it to Petalifera.
I will keep it as Petalifera cf. ramosa. It differs from Petalifera ramosa by the lack of the rounded tubercles with white basal ocelli.
Pretty similar is Stylocheilus longicauda which differs by the bright yellowish-green body colour, the long tail, and blue spots with orange-red ocelli.
More information on Petalifera ramosa are on Bill Rudman's Sea-Slug Forum!
How to cite:
Köhler, E. (2011), published 20 September 2011, Petalifera cf. ramosa  Baba, 1959
available from https://www.Philippine-Sea-Slugs.com/Anaspidea/Petalifera_ramosa_cf.htm