Biscogniauxia capnodes (Berk.) Y.-M. Ju & J. D. Rogers
TELEOMORPH | CULTURES AND ANAMORPH | SPECIMENS EXAMINED | NOTES
NOTES
Biscogniauxia capnodes is the most commonly encountered taxon of the genus. Our concept of B. capnodes embraces var. exutans (Cooke) J. H. Miller, var. merrillii (Bres.) J. H. Miller, and var. pseudopachyloma (Speg.) J. H. Miller of Hypoxylon nummularium Bull.: Fr. [º Biscogniauxia nummularia (Bull.: Fr.) Kuntze] in Miller (1961). We do not consider these varieties as recognized by Miller (1961) to be separate taxa. It is worth mentioning that Miller (1961) misinterpreted the type of var. exutans which is possibly a synonym of B. fuscella (see NOTES on B. fuscella). Miller (1961) separated these varieties largely on small differences in ascospore size ranges and, to a lesser extent, on ascospore shape. Cultures from collections with ascospores falling into different size ranges do not appear to differ. Moreover, delimiting ascospores of various collections into size ranges given by Miller (1961) is difficult and can be done only for a few collections. It appears to us that B. capnodes is a species distinct from B. nummularia. They can be easily separated by stromatal anatomy and ascospore shape. Biscogniauxia capnodes has carbonaceous tissue between perithecia and ellipsoid ascospores, whereas B. nummularia has gray to brown, woody tissue between perithecia and more rounded ascospores. Geographically, Biscogniauxia nummularia is largely confined in Europe, whereas B. capnodes has apparently been infrequently collected in Europe.