Phylum Ascomycota Caval.-Sm. (1998) - sac fungi Subphylum Pezizomycotina O.E. Erikss. & Winka (1997) Class Eurotiomycetes O.E. Erikss. & Winka (1997) Subclass Eurotiomycetidae Tehler ex Geiser & Lutzoni (2007), nom. inval. Order Onygenales Cif. ex Benny & Kimbr. (1980) Family Onygenaceae Berk. (1857) Genus Xanthothecium Arx & Samson (1973)