A lionfish swims among coral in Rockstar's Leonida Keys 07 screenshot, with a diver and a boat behind it. Rockstar names the fish in its Launch Gallery.
Rockstar Games
In the Leonida Keys 07 screenshot, from Rockstar's Launch Gallery, a striped lionfish swims among coral while a diver with a flashlight passes behind it and a boat idles on the surface. Rockstar's description of the image calls it a lionfish. It hasn't said where else lionfish turn up or how they behave. Scuba diving is one of GTA 6's side activities.