A taxonomic revision of the North American species of Lepraria s.l. that produce divaricatic acid, with notes on the type species of the genus L. incana.

The divaricatic acid-producing populations of Lepraria in North America north of Mexico are revised using traditional morphological characters, chemistry, ecology, biogeography, and ITS1, 5.8S, and ITS2 sequence data. Three taxa are accepted: L. cryophila, L. hodkinsoniana sp. nov., and L. pacifica sp. nov. Both Lepraria crassissima and L. incana are excluded from the study area. Non-cryptic, semi-cryptic, and fully-cryptic species concepts in Lepraria are discussed with a special emphasis on the practical integration of molecular characters into taxonomic frameworks based on non-molecular characters.