| Noun | 1. | family Xylariaceae - family of fungi characterized by dark brown to black spores fungus family - includes lichen families order Sphaeriales, Sphaeriales - large order of ascomycetous fungi usually having a dark hard perithecia with definite ostioles; in more recent classifications often divided among several orders genus Xylaria, Xylaria - type genus of Xylariaceae; fungi with perithecia in the upper part of erect black woody stromata genus Rosellinia, Rosellinia - fungi having smooth perithecia with dark one-celled ascospores |