Introduction to Xylariaceous fungi



European genera belonging to Xylariaceae Tul. & C. Tul. exhibit a wide range of morphological variations that are to be illustrated in the present work. Xylariaceae is a family in which, besides outstanding variations in morphological features, the combination of the following characters is shared by all genera : perithecia enclosed in (or covered by) a stroma, unitunicate asci with an apical apparatus which is frequently bluing in Melzer's reagent (amyloid), paraphysate hamathecium and brown ellipsoid ascospores which are usually one-celled and provided with a germ slit or a germ pore.

Stromatal morphology and structure, situation of the perithecia within the stroma and identification of anamorphs are the main characters used in separating xylariaceous genera. At the specific level, ascospores characters are frequently the most discriminant ones, along with morphological and chemical characters of the stromata.

Before the taxonomic treatment of each genus, a key to the genera formerly classified as Hypoxylon and other xylariaceous genera is proposed, after the more complete keys proposed by Ju & Rogers (1996) and Rogers & Ju (1998).