Uperoleia orientalis (Parker, 1940)
This frog is easily distinguished from Uperoileia laevigata as the photo shows. Slightly larger this species grows to about 3 cm, and is only found in the tropical part of the Northern Territory.
A ground dwelling species, it is found in large numbers breeding around swamps and flooded grasslands during the wet season.
Uperoleia orientalis is generally nocturnal.

The above was from the book Australian Reptiles and Frogs by Raymond Hoser and now available on a fantastic CD-Rom along with a vast amount of other information, papers and the like on reptiles, frogs and other wildlife.