The South American polka dot tree frog turns from green, yellowish-red to blue and green when exposed to UV light.
Researchers in South America have discovered that the South American polka dot tree frog (Hypsiboas punctatus) a fairly common amphibian, has the capability to fluoresce from a normal coloration of greens, yellows, and reds, to a bright blue and green glow when exposed to ultraviolet illumination.
The scientific term is called fluorescence, and it is apparently very rare in terrestrial animals. And until now was never seen before in an amphibian. According to a report in Nature, fluorescence was only known to occur in certain parrot species and some scorpions on land and with creatures such as corals, certain fish and sharks, and the hawksbill turtle (Eretmochelys imbricata), in the ocean.
The researchers told Nature.com that they had pointed a UVA flashlight at a polka dot tree frog that was collected near Santa Fe, Argentina and found that the little frog gave off a greenish-blue glow instead of the faint red that they had thought it would emit.
"We couldn’t believe it,” said study co-author Julián Faivovich, a herpetologist with the University of Buenos Aires.
The researchers hope to study more tree frogs to see if other species fluoresce like that of the South American polka dot tree frog.