I would have sworn this mushroom was Agaricus augustus and it seemed to have many of its macroscopic characteristics. So I was very surprised to get a DNA sequence for this mushroom confirming with 99% certainty that this mushroom is actually Agaricus flocculosipes.
This species was first described from Thailand from the arvensis clade of Agaricus although this species was reported as larger and potentially a great cultivation option.
Thanks to Wayne Boatwright in South Eastern Queensland. Wayne was kind enough to authorise the use of these photos so that the record can be kept here for interest purposes.
While Agaricus can be hard to start from spore im hoping we can get a culture of this guy going!
Thanks Wayne – these photos are copyright Wayne Boatwright.
More recently we found a similar mushroom in Victoria, Australia which we also believe is augustus: