The discovery of two species of frogs from the high rainfall zone of the northwest Kimberley has been announced following their formal description this week in the Records of the Western Australian Museum and Zootaxa.

The first species is called the Tiny Toadlet (scientific name – Uperoleia micra) and is just over 2 cm long. It was discovered near the Prince Regent River when it was first heard calling behind helicopter pilot Butch Maher’s tent. The new species is extremely shy and would not have been discovered if its call did not differ from those of three related species in the area. 'Toadlets' are not true toads, but a group of native frogs that have a stocky appearance with moderately developed poison glands (but nothing like those of the Cane Toad). The Kimberley is host to the highest diversity of Toadlets in Australia.

The second species, the Kimberley Froglet (Crinia fimbriata), was discovered on the Mitchell Plateau – an area previously believed to be well surveyed for frogs. It is also about 2 cm in length. It was noticed owing to its blue and red background colour and covered with tiny white dots, similar to some Aboriginal painting styles. Males of this species have flanges on the fingers, but it is not known what the flanges might be used for. Its call has not been recorded.

The discovery of two frog species in the northwest Kimberley (from the Mitchell Plateau to the Prince Regent River) emphasises the high diversity of the area, which may be considered for World Heritage listing in the coming years. The very rugged northwest Kimberley region is being increasingly impacted by tourism, mining and gas development projects and the impact of feral weeds, cattle and soon the Cane Toad.

Dr. Paul Doughty of the WA Museum said, "The northwest Kimberley has a high diversity of frogs and reptiles that are unique to the region, as it receives high rainfall in summer and the area is cut-off by drier regions to the south. Many of the species that occur there have been evolving there in isolation for millions of years, and there are certainly more species to discover from the area."

"Other than being able to describe these two new species, we know very little about their behaviour and habits. To me they are like new friends that we are just getting to know" he said.

The discoveries were made possible by a research grant through Alcoa of Australia to support the WA Museum’s Alcoa Frog Watch programme. Also participating were Dale Roberts of UWA, Marion Anstis – Australia’s tadpole expert, student Luke Price from the SA Museum and many others.