Leucoagaricus aff. marginatus (Burl.) Boisselet (2002)

 
There seems to be lack of clarity as to what exactly Burlingham described as Leucoagaricus marginatus. I believe that this collection represents it. it has distinctly shorter spores of smaller Q-ratio than Leucoagaricus cupresseus and doesn't bruise red on any surface.
Leucoagaricus marginatus spores

Spores: 6.2-7.5x4.3-5.5
, dextrinoid  ~7x5
Leucoagaricus cupresseus spores

Spores: (7.0) 7.3-9.1 (9.6) x 4.0 -4.5 , dextrinoid

Cuticle

Typical cheilocystidia 25-37
(length)