These were taken in Cozumel. Not my best photos, I know. The closest ID I can find is in Mickey Charteris' book Caribbean Reef Life, and that is the Warty Aeolid. The photo in the book is similar to my pictures but when I look on the internet, I get something totally different. I've reached out to Mickey for his thoughts but wondered if anyone here had any ideas?

Taken with Olympus EM-1 Mk III, Olympus 30mm lens and Backscatter HF-1 strobe.

Edited 10 hours ago10 hr by JS1221

Nuidbranch names do change quite often and also it is best to use the scientific name when searching as the common name can be shared by a number of species. Google search the scientific name to see if what comes up matches your pic.