A revision of the North American lichen genus Ahtiana.
The formerly monotypic genus Ahtiana (type species: A. sphaerosporella (Müll. Arg.) Goward is shown to include two additional species, A. aurescens (Tuck.) Thell & Randl. and A. pallidula (Riddle) Goward & Thell. All three species are endemic to North America, and are characterized by their greenish yellow upper surface, globose ascospores, and caperatic acid in the medulla. The habitat ec
