Rarest tree frog

The rarest species of tree frog is Rabbs' fringe-limbed tree frog Ecnomiohyla rabborum. Discovered by science as recently as 2005, it was formerly present in the forest canopies of central Panama, but today only one living specimen is currently known to exist – a lone male living at the Atlanta Botanical Garden in Georgia, USA. Until 2012, it had a companion, a male at Atlanta Zoo, but sadly this latter specimen had to be euthanised when it became untreatably ill. The last known female specimen died in 2009.