Gladiator tree frog (Hyla rosenbergi), Osa Peninsula, Costa Rica
The Gladiator tree frog (Hyla rosenbergi) is named for the fighting behavior of males among some populations. The male Gladiator tree frog has a bony spine (an “unsheathed prepollex spine”) on each hand which is used in fights over females. Fighting frogs aim to gouge out their opponents’ eyes and puncture their eardrums. Frogs are often maimed or killed in the duels. Those that survive and are successful in finding a mate and reproducing will defend their young against competitors and predators.
The Gladiator tree frog ranges from Costa Rica to Ecuador.
This picture is part of mongabay’s 2009 collection of nature photos.