Hmm, i think perhaps a limnodynastes species. It's got spots like a tasmaniesis (spotted marsh), but this guy is a bit warty and has red patches.... i'll go on a hunt and let ya know what it is..
I have discussed with my froggy experts and they came to the conclusion that you have there a Opisthodon ornatus formally Limnodynastes ornatus the Ornate Burrowing Frog.