Allison found this guy in a sand patch. We saw what were obvious Blue Goby by their elongated, pointed caudal fins and then this guy nearby and her buddies. We are pretty certain it is a Hovering Goby but we'd like a confirmation from the panel :)
Nice! A Dartfish! Blue Dartfish, Ptereleotris calliurus
Take a look at the rounded caudal fin, it doesn't come to a point like the Blue.
The blue is in FL and the Gulf of Mexico; in the Caribbean they are hovering gobies- Ptereleotris helenae, and can have very rounded tails, or sometimes pointed. Not the best character.
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