I could be wrong i dont know all the technical stuff, i just go off the 'vibe' of its appearance. Im sure someone who knows their stuff will correct me if im wrong.
You can tell easily that it a barbata as the spines form rows down the tail, though this is less visible in some barbata, but most have it and no vittie does.
Thanks for identifying it - Im not that up to date on the differences - there is a few of them along our street so hopefully there will be more appearing. Its the first time i have seen them there in the 5 years i have been living there.
Yeh, they arn't as common as they used to be around Sydney, but still turn up in odd places. They often get called "a escaped pet" as they rarely try to run away and usually calm down within a few days in captivity. We had heaps of them around Engadine / Menai 20 years ago, but now they are almost gone with only the odd one turning up out the back of menai every now and then.