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The pictures #8 - #10 show the same specimen, #9 with the gills extended, #10 with retracted gills.
It was desbribed by Kelaart in 1858 from Ceylon, since 1972 known as Sri Lanka.
Bill Rudman writes in a comment at the Sea-Slug Forum:
"Unfortunately, Vallès & Gosliner do not include P. ceylonicus in their review of the genus so I can't comment on their reasons for proposing the new species P. maculapodium. Two other new species in their paper, P. lemur and P. pecoso would also appear to be colour forms of this orange spotted 'species'..."
That is Plocamopherus maculapodium, Plocamopherus cf. maculapodium, Plocamopherus lemur, and Plocamopherus pecoso are possibly synonyms of Plocamopherus ceylonicus.
References Kelaart, E.F., 1858. Description of a new Ceylonese nudibranch. Annals and Magazine of Natural History, series 3, 1(4): 257-258. Valles, Y. & T.M. Gosliner. 2006. Shedding light onto the genera Kaloplocamus and Plocamopherus (Mollusca: Nudibranchia) with description of new species belonging to these unique bioluminescent dorids. The Veliger, 48: 178-205.
More information on Plocamopherus ceylonicus are on Bill Rudman's Sea-Slug Forum!