12/18/08 (Information from FFI and BBC) A frog with green blood and turquoise bones has been discovered in Cambodia's remote Cardamom Mountains, international conservation organization Fauna & Flora International (FFI) announced today.

The Samkos bush frog (Chiromantis samkosensis) is thought to be extremely rare, the UK-based charity said in a news statement. "Its strange colored bones and blood are caused by the pigment biliverdin, a waste product usually processed in the liver.

"In this species, the biliverdin is passed back into the blood giving it a green color; a phenomenon also seen in some lizards. The green biliverdin is visible through the frog's thin, translucent skin, making it even better camouflaged and possibly even causing it to taste unpalatable to predators."

The frog was first seen in 2000 but officially identified as a new species only last year. An FFI expedition in 2008 to look for more Samkos bush frogs could find only one individual, which was perched on a reed above the road where its breeding pond used to be.

"It appears the species is highly localized, breeding in temporary rain pools in evergreen forest at around 500 metres above sea level. Nothing else is known about its ecology," the FFI statement says.

Fauna & Flora International consultant naturalist and photographer Jeremy Holden, who discovered the Samkos bush frog, said: 'When I found the frog, I had a thrilling suspicion that we were looking at an entirely new species of amphibian. Photographing these frogs has been a challenge. They were extremely difficult to find, but thanks to their distinctive calls we managed to get some excellent shots and record them for posterity."

The new frog is one of four "new-to-science" frog species discovered by FFI in Cambodia. Cambodia's national list of amphibians now stands at 63 species.

"A Field Guide to the Amphibians of Cambodia", authored by Jeremy Holden, was published by FFI in October.