Hypoxylon sassafras (Schwein.: Fr.) M. A. Curtis has long been considered
to be a Hypoxylon and described under this name by Miller (1961)
and Petrini and Müller (1986). Indeed it shared most of distinctive features
of this genus as defined by these authors, until it was segregated from Hypoxylon
by Ju et al. (1993) who resurrected the genus Creosphaeria Theiss.
to accommodate it.
Hypoxylon sassafras, as most of Hypoxylon taxa retained by
Ju and Rogers (1996), has lignicolous waxy stromata with orange granules
yielding orange pigments in 10% KOH, asci provided with an amyloid apical ring
and brown ellipsoid ascospores with a germ slit. But unlike Hypoxylon
which is defined as having Nodulisporium Preuss anamorphs, cultures undertaken
by Petrini and Müller (1986) and Ju et al. (1993) proved that H. sassafras
has a Libertella Desm. anamorph, that is characteric of Diatrypaceae
Nitschke and of some other xylariaceous genera of uncertain position [Lopadostoma
(Nitschke) Traverso, Ju et al. (1993), Barrmaelia
Moreover, it differs from most Hypoxylon taxa in being usually uniperitheciate,
although stromata are frequently found fused together, and in having large perithecia
frequently more than 1 mm diam in solitary stromata.
As far as known (Ju et al., 1993) Creosphaeria is a monospecific
genus, although C. sassafras has a worldwide distribution and has been
described under a lot of different names. For synonymy, the reader is referred
to Miller (1961) and to Ju et al. (1993).