Scientists have discovered two new rock-climbing frog species in a remote area of north-east Queensland.

The kutini boulder frog and golden-capped boulder frog were found living in two different piles of granite boulders in an area of rainforest in the Cape York Peninsula.

Dr Conrad Hoskin from James Cook University says the frogs use their unusually long fingers to climb rather than hop - a trait they developed to survive in their rocky environment.

"The frogs have long arms, long slender fingers and big triangular finger pads, which enable them to climb among the labyrinth of rocks," he said.

"They only occur in the rocks and never in the surrounding forest and although they're highly localised, they're abundant where they occur."

Dr Hoskin says the frogs live deep amongst the rocks and only come to the surface when it rains in the summer wet season.

"You can sit there as darkness falls and watch these amazing frogs emerge from the boulders all around you," he said.

He says the terrain is so remote he had to be flown in.

"[The frogs were among] just thousands of granite boulders all piled in there," he said.

"And its really deep; you could climb way down in amongst them."

Dr Hoskin says there were not a lot of creatures living on the boulders as it was such an "unusual habitat".

"One of the creatures living on it are these frogs and there's also a few geckos and lizards and various spiders and insects as well," he said.

The newly-discovered frogs eat ants for their main source of food and lay eggs on land, Dr Hoskin says.

"They lay their eggs on land and the tadpoles develop within the egg and miniature frogs hatch out before they head off into the forest or boulders," he said.

"Most Australian relatives of these frog species are only about 2 centimetres in length, but these new ones are comparatively huge at 5 centimetres."