This is where people get confused looking at written info on line.
Actually, you can find every type of head scalation that occurs within BHPs in "west" aussie. The only place you see scalation differences is in the Southern Coastal Pilbara region. All of the animals in this area have single loreals, no sub oculars and one pair of Parietals.
Anywhere else in west aussie...they can appear just like any other BHP from any other part of Australia.
D