Scientists around the world have previously discovered that some other species of mammals, fish and insects glow under ultraviolet light.
However, this had never been spotted in bats in North America before.
Experts from the University of Georgia in the United States decided to take a closer look at sixty different bat specimens under UV light.
They found that six different species – big brown bats, eastern red bats, Seminole bats, southeastern myotis, gray bats and Brazilian free-tailed bats – all glowed green.
According to the study, the glow appeared mostly on the wings and hind limbs of bats.
The team say the colour and location of the glow suggest that it is a genetic characteristic – passed down through bat groups – and not something related to the environment where the bats live.
However, experts say that the reason why the glow might help the bats is still unknown, but they think it could be to do with communication.
Steven Castleberry, author of the study, explained: “The data suggests that all these species of bats got it from a common ancestor. They didn’t come about this independently.
“Maybe glowing served a function somewhere in the evolutionary past, and it doesn’t anymore,” he added.