This Philippine nudibranch is characterized by a prominent gill plume, camouflaged drab appearance, knotty pustules and green broccoli-like clustered tubercules along its mantle.

I have listed this as an unknown nudibranch for some time. Recently Erwin Kohler, proprietor of the fine Mediterranean Slug Site, listed this as Dendrodoris tuberculosa (family Dendrodorididae) after consulting with a colleague (I am retaining the page name in order to preserve external links).

Here are some other links to photos or illustrations of Dendrodoris tuberculosa, with some from some extraordinary web seaslug resources: Bob Bolland's slug site, the Australian Museum's Sea Slug Forum, and Mike Miller's slug site:

Identification: Dendrodoris tuberculosa