The defining features of the Amanita muscaria species group are:
The presence of warts on the cap;
The presence of a ring on the upper stem;
Concentric zones of shagginess at the top of the swollen stem base.
And how about these beauties growing under my Peggy Martin Rose. They've come up before but this morning I had 12. The most common mushroom I find in my yard is tricholoma pardinum the generic squat, whitish mushroom with brown spots, and this tiny skinny brown thing that literally seems to melt by afternoon. Next time I buy compost I'm going to check out that mushroom compost and see what kind of stuff I get growing!