Though this may really look like a nudibranch (and in particular one I’ve shared before), this is actually a juvenile sea cucumber – probably a Black Spotted Sea Cucumber (Bohadschia graeffei). One particular point you can use to spot the difference is the tube feet…

Yes, you read that title correctly… this is a very deadly snail in the cone snail family. While I was on my Timor Leste expedition with Blue Ventures, our hazardous marine creatures lecture included a section about cone snails… of course most people scoff at…