Do I know anyone here with a saltwater reef tank? Ever had to deal with a flatworm infestation?
I recently got some biopsies from Caribbean Acropora that were losing tissue and dying. These guys are full of flatworms, and while there are several species of flatworm described on corals in the Pacific and in aquaria on Pacific species, I can't find any references that mention a Caribbean variety, or even an Atlantic one, at all. It's pretty difficult to get an ID beyond "flatworm" from routine histology but I might get tissue to sequence using laser capture microdissection that I can compare to other known species.
I think these might be escapees from someone's hobby aquarium, just possibly. It's also possible that they are a native species no one noticed before but the fact that they are such a big aquarium pest has me worried.
This is why we should never dump an aquarium into wild waters or release any kind of pet that isn't native, or even that is but has had contact with non-native species, into the wild. You never know what else you're unleashing. You might be killing coral reefs.