From the location, likely A. aethiopicum, but the indented pinnae look a little like A. capillus veneris. Not recorded from near Canberra, but an interesting possibility. Definitely worth further investigation.
According to my trusty old Jones and Clemesha, A. aethiopicum has its sori in the dents in the pinnae, but A.capillus veneris has them on the tips of the lobes of the pinnae