Leucoagaricus americanus

Leucoagaricus americanus, commonly known as the American parasol,^[2] is a species of fungus in the genus Leucoagaricus. It is widely distributed in North America, mostly east of the Rocky Mountains. It is saprobic and grows on sawdust, wood chips, stumps, and the ground.

The species was first described by American mycologist Charles Horton Peck in 1869.

The cap is oval in shape when immature, becoming convex to flat when fully grown, reaching up to 3–15 centimetres (1+1⁄4–6 in) wide.^[3] The cap feels dry and smooth at the beginning, but gradually gets reddish to reddish brown scales. It is white in color but reddens with maturity or after being handled.^[4] The gills are free from the stipe and lie close together. They appear white when young and are stained pinkish to maroon. The stipe is 7–14 cm long, often enlarged at or below the middle and tapering toward the base. It appears white at first, staining or aging pink or reddish brown. It feels smooth with its silky hairs. The membranous veil leaves a white double edged ring on the upper stipe that may disappear in age.^[5]

The spores are white to cream in color and measure 8–10 x 6–7.5 μm.^[1] The flesh is white throughout. It bruises yellow to orange when young but dries reddish when mature. The flesh is thick and discolors when cut, bruised or damaged.^[5]

It is reported to be edible, but not recommended for consumption because of possible confusion with toxic species like Chlorophyllum molybdites.^[5]

It is widely distributed in its native North America,^[5] though more common east of the Rocky Mountains; it is saprobic, and grows on sawdust, on wood chips, on stumps, and on the ground.^[4]

• List of Leucoagaricus species