Inconclusive sighting

The gills don't look dark enough for an Agaricus. There seems to be a slight ring of tissue around the upper part of the stem, suggesting that a partial veil covered the gills at an earlier stage. I'm guessing the spores were a rusty brown or pale brownish and wonder if this is a Cortinarius or Hebeloma. Pam or Ken might have a better idea.

Yes the gills don't look right for Agaricus. The habitat seems to be herbivore dung - probably horse given the location. If it is a dung fungus that would most likely rule out Cortinarius and probably Hebeloma, but as a dung fungus its not one I recognise. Alternatively the presence of dung and the fruit body together is no more than coincidence. The gills don't seem to be free, instead they run right into the top of the white stipe - so possibly adnexed, but the resolution is too low to be certain.

The dung is kangaroo pellets. Although Attunga Point is a fenced reserve, kangaroos can get under the fence and the reserve is grazed to some extent!

Like Ken, I don't recognize this as a dung fungus and I assume the fungus/dung proximity is coincidental.

Not Agaricus, I agree. Then the Cortinarius, and there are just so many variations with the number of species that are around. Or Hebeloma, which is a good possibility as well. Beats me sorry!