| Xylaria laevis Lloyd, 1918 |
| Xylaria lancea Lloyd, 1918 |
| Xylaria liquidambaris J. D. Rogers, Y. M. Ju & F. San Martín, 2002 |
| Xylaria longiana Rehm, 1904 |
| Xylaria longipes Nitschke, 1867 |
| Xylaria longipes var. longipes Nitschke, 1867 |
| Xylaria longipes var. tropica F. San Martín & J. D. Rogers, 1989 |
| Xylaria luxurians (Rehm) Lloyd, 1918 |
| Xylaria magniannulata F. San Martín & J. D. Rogers, 1989 |
| Xylaria magnoliae J. D. Rogers, 1979 |
| Xylaria magnoliae var. magnoliae J. D. Rogers, 1979 |
| Xylaria maitlandii (Dennis) D. Hawksw., 1973 |
| Xylaria melanura (Lév.) Sacc., 1886 |
| Xylaria mellissii (Berk.) Cooke, 1883 |
| Xylaria mellissii var. mellissii (Berk.) Cooke, 1883 |
| Xylaria mellissii var. nuda (Dennis) D. Hawksw., 1973 |
| Xylaria mexicana F. San Martín, J. D. Rogers & P. Lavín, 1998 |
| Xylaria michoacana F. San Martín, J. D. Rogers & P. Lavín, 2001 |
| Xylaria microceras (Mont.) Berk., 1851 |
| Xylaria multiplex (Kunze) Fr., 1851 |