P sexpustulata (Marsham, 1808) has bright spots. P. rufobrunnea (Blackburn 1898) is brown without any spots whatsoever. These have identical shape and genitalia and are possibly the same species. However populations are quite distinct. Sexpustulata never occus into Victoria and rufobrunnea is scarce in NSW, although a few near ACT. There are several records of this lightly spotted species, with varying degrees of brightness, impossible to place in one or the other. A dissection will fail to make a determination, since genitalia are identical anyway. If they are synonymized, which I doubt, since they look so different, P. sexpustulata will be the senior synonym, and the true name. The lightly spotted form occurs in Victoria here. https://www.inaturalist.org/observations/110088578 . NSW here https://www.inaturalist.org/observations/148493686