Lepraria torii is a species of corticolous and lignicolous (bark- and wood-dwelling), leprose lichen in the family Stereocaulaceae.

[1] Lepraria torii is a crustose and leprose lichen, meaning it forms a crust-like thallus layer on the surface it grows on (episubstratal) with a powdery texture and a well-defined border.

However, the soredia (powdery reproductive structures) beneath the cortical area can form a whitish layer in the thickest parts of the thallus.

The hypothallus, the layer beneath the thallus, is composed of a network of whitish tangled hyphae, which are about 2.5 μm wide.

[1] Lepraria torii is predominantly found in old-growth forests ranging from sea level to nearly 1,100 m (3,600 ft) in elevation.