Carinata are much smaller than paulsoni. Maximum lengths for carinata are around 24 inches (and they are thin) with paulsoni getting up over 3 feet in some cases. Most carinata around have a lightened coloration right above the cloaca on their back too...most, but not all.

Its actually easy to tell them apart once you have seen both, but do you have pics?
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John R. Stebbins
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1.1 Candoia bibroni australis
0.2 Candoia carinata carinata
1.0 Candoia paulsoni
2.0 elaphe guttata guttata