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It looks at least like Doris sp. 4 in IPN at page 156
Let me quote the description:" This species can be easily recognized by its yellow body with rounded tubercles where some are tipped with black pigment. The gill also contain black pigment while the rhinophores are yellow."
This species or a pretty similar one was the 'Opisthobranch of the Week' at Michael D.Miller's Slug Site on 09 June 2008Reference:
Gosliner, Terrence M., David W. Behrens & Ángel Valdés. 2008. Indo-Pacific Nudibranchs and Sea Slugs.
Sea Challengers Natural History Books. Gig Harbor, Washington. 426pp.
How to cite:
Köhler, E. (2017), published 20 April 2017, Doris sp. 02 Genus: Linnaeus, 1758
available from https://www.Philippine-Sea-Slugs.com/Nudibranchia/Euctenidiacea/Doris_sp_02.htm