Cystoderma carcharias var. fallax, commonly known as the sheathed powdercap, is a mushroom in the genus Cystoderma.
Cystoderma carcharias var. fallax has a tan or brown cap that is covered in scales or granules. It is about wide. The stipe is about tall and about wide.
Cystoderma carcharias var. fallax grows on rotten logs, in moss, and in conifer needles. It fruits in the fall.