Knudsen, K. & Kocourková, J. 2016. Acarospora sphaerosperma (Acarosporaceae), new to Europe and the Czech Republic, and Acarospora irregularis, new for Austria. — Herzogia 29: 465–472.
Acarospora sphaerosperma, a species described from the Ozarks in North America, is reported new for Europe from Bohemia in the Czech Republic. The species is expected to be more widespread in Europe. An earlier European name has not been found. Acarospora irregularis is reported new for Austria.