A new study says that this small eel photographed by accident on a Caribbean coral reef is the first green fluorescent fish ever recorded.
From National Geographic:
The first bright green fluorescent fish ever recorded in the wild, their discovery dates back to 2011, when a tiny eel photobombed David Gruber off Little Cayman Island in the Caribbean. For Gruber, who was photographing biofluorescent corals at the time, the finger-length eel couldn’t have been more illuminating.
“This big lightbulb went off in my head,” says Gruber, a National Geographic Explorer and marine biologist at City University of New York. “I hadn’t expected a fish to be glowing as brightly as the coral.”
That discovery sparked a new investigation into biofluorescence in marine animals. So far Gruber's work has helped identify more than 180 species of biofluorescent fish, uncovering the stunning extent to which marine vertebrates manipulate light to create color in their uniformly blue environment.
More on the study and the little eel at National Geographic.