Phylum Ascomycota Caval.-Sm. (1998) - sac fungi Subphylum Pezizomycotina O.E. Erikss. & Winka (1997) Class Sordariomycetes O.E. Erikss. & Winka (1997) Subclass Sordariomycetidae O.E. Erikss. & Winka (1997) Order Sordariales Chadef. ex D.Hawksw. & O.E. Erikss. (1986) Family Chaetomiaceae G.Winter (1885) Genus Achaetomium J.N. Rai, J.P. Tewari & Mukerji (1964)