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It looks similar to Goniodoridella sp. 7 in IPN:
Gosliner, Terrence M., David W. Behrens & Ángel Valdés. 2008. Indo-Pacific Nudibranchs and Sea Slugs. Sea Challengers Natural History Books.
Gig Harbor, Washington. 426pp. at page 128,
which differs by black spots on the body and by a median black patch in front of the rhinophores.
Pretty similiar is:
Goniodoridella sp. 05 which lacks the black line running down from the 'crescent' at the sides in a posterior slant, and differs by small irregular brown spots.
This species was posted on 17 May 2011 on these websites as Goniodoridella sp. A Genus: Pruvot-Fol, 1933,
and changed on 10 August 2011 into Goniodoridella sp. 01 Genus: Pruvot-Fol, 1933.
For some genera, such as Trinchesia was the alphabet almost through. I had to change the distinguishing alphabetic character into a number. I had chosen 2-digit numbers, even though '01' looks a little bit stupid, and now is only the genus italic written.
How to cite:
Köhler, E. (2016), published 31 March 2016, Goniodoridella sp. 01 Genus: Pruvot-Fol, 1933
available from http://www.Philippine-Sea-Slugs.com/Nudibranchia/Euctenidiacea/Goniodoridella_sp_01.htm