Hi Ian, your observations are correct, it didn’t have the obvious cream and orange costa as shown in the book. That will just be another one i’ll be on the look out for now.
There seems to be uncertainty in our distinguishing P, bicosta from Paleaosia (genus) generally on CNM. I think we need to investigate more thoroughly from set specimens.
As Ian says, it's the Palaeosia undescribed species shown in Moths in the ACT. It should have its own "Palaeosia undescribed species" rather than be in the "Palaeosia (genus)" category.