| Cenangium Fr., 1822 |
| Cenangium yuccae Clem. & E. G. Clem. ex Seaver, 1951 |
| Claussenomyces Kirschst., 1923 |
| Claussenomyces salviicolor (Ellis & Everh.) Korf & J. R. Dixon, 1974 |
| Coryne Nees, 1816 |
| Coryne atrovirens (Pers.) Sacc., 1889 |
| Crocicreas Fr., 1849 |
| Crocicreas pilifera Raitv. & R. Galán, 1994 |
| Crocicreas sessilis Samuels & Rogerson, 1990 |
| Crocicreas sulphurea Raitv. & R. Galán, 1994 |
| Cyathicula De Not., 1863 |
| Cyathicula coronata (Bull.) Rehm, 1893 |
| Helotiaceae Rehm, 1886 |
| Helotium Pers., 1801 |
| Helotium citrinum (Hedw.) Fr., 1849 |
| Helotium rufo-corneum Berk. & Broome, 1875 |
| Hymenoscyphus Gray, 1821 |
| Hymenoscyphus caudatus (P. Karst.) Dennis, 1964 |
| Hymenoscyphus epiphyllus (Pers.) Rehm ex Kauffman, 1929 |
| Hymenoscyphus fructigenus (Bull.) Gray, 1821 |