A fish

I'm acutely aware we haven't had as much marine life as we usually do of late. I'm working on it but for now here's a horse-eye jack to tide us over.

This is your fairly standard trevally-shaped fish - big eyes for vision, huge tail for bursts of speed very narrow and streamlined, big, sharp scutes down the end of the lateral line. The perfect smash and grab predator on the reef.