
Porpoloma umbrosum

Porpoloma umbrosum, commonly known as the amyloid tricholoma, is a species of fungus in the family Tricholomataceae, and the type species of the genus "Porpoloma". It was first described scientifically by mycologists Alexander H. Smith and Maurice B. Walters in 1943 as a species of "Tricholoma". Rolf Singer transferred it to "Porpoloma" (subgenus "Pseudotricholoma") in 1962. The mushroom is found in North America, where it fruits singly or in small groups under conifer trees. Although it resembles "Tricholoma" species, it is distinguished from that genus by its amyloid spores.