Macrolepiota is a smaller genus in the very large family Agaricaceae.  The species in North America are poorly described and likely  genetically different from Eurasian species (this is at least likely for  M. procera).

As seen in the images, the mature fruitbody takes on a distinctive parasol shape on a very tall (over a foot!) stipe. 

Young Cap Shape: Lepitoid 

Lepitoid immature cap shape, chevrons not yet present

The young cap will usually be found in the bullet-shape (sometimes described as egg-shaped) seen in this image, and NOT a more rounded ball (typical of Chlorophyllum species). This bullet shape is commonly seen in Lepiota and similar genera. When the cap opens into it's typical parasol shape, there will be a brown umbo (raised nipple) in the center of the cap and distinct brown scales.

Stipe: Snakeskin Pattern

The stipe holds some critical characteristics that separate M. procera from its most common and toxic look-a-like, Chlorophyllum molybdites. M. procera has an ornamented stipe that usually takes on small chevron (triangles) shaped scales. The annulus (ring) has flares on the top and bottom and if grasped, can be easily moved up and down the stipe.

Deep Gills

The gills are free (do not attach to the stipe), white (sometimes with a rosy tinge), crowded, and will drop a white spore print (not even a little green!)

The margin (edge of cap) will have remnants of the sterile partial veil that contained the gills prior to the parasol opening. 

Cap Texture

The texture of the cap is slightly different than its look-a-likes. The base color is a light beige and contains both fibrous threads and the darker overlaying scales. The fruitbody will have a pleasant nutty smell.

The most common source of non-lethal mushroom toxicity is the 'false-parasol' Chlorophyllum molybdites. While some species of the Chlorophyllum genus are edible, we recommend you take extra precautions that we are unable to provide here.

Chlorophyllum look A LOT like M. procera, but there are some giveaways that we can detect. Don't forget, when in doubt, throw it out!

Chlorophyllum commonly pop up in treated fields and lawns and frequently fruit in large, attention-grabbing "fairy rings"

Unornamented Stipe

Chlorophyllum will have a smooth unornamented stipe (no chevrons or anything like them)  just smooth tan/brown. Note that the ring which IS normally present in Chlorophyllum species is missing (it was removed).

Similar Scaled Cap

Note how similar this cap color and texture is to M. procera. Don't use the cap as the defining feature for either.

Immature Cap Shape: Round

Here you can see the shape of young C. molybdites' caps. They quickly take on a 'ball on a stick' shape and lack the bullet shape that is more common for M. procera. This is another characteristic that is helpful, but not enough for a confident differentiation.

Photo by John Richard Ramsey

Green Spores

Chlorophyllum molybdites will drop a green-colored spore print and older specimens will show the green spores on the gills, as shown here.

Photo by Jessy Coxson

Photo by Deacon Mcdaniel

Coming soon!