Biscogniauxia fuscella (Rehm) San Martín & J. D. Rogers

TELEOMORPH | CULTURES AND ANAMORPH | SPECIMENS EXAMINED | NOTES

NOTES

This fungus has a white to buff-colored outer dehiscing layer. The stromatal surface is pale mouse gray when young, becoming darker afterwards. It is noteworthy that B. fuscella shows a cellular appendage on some mature ascospores. The cellular appendage is readily observed on immature ascospores. While ascospores are maturing, the appendage usually disintegrates and thus only persists on some mature ascospores. Vertical sections of stromata reveal that B. fuscella has the hypothetical stromatal anatomy diagrammed in Fig. 5C of Ju and Rogers (1996). Miller (1961) placed this fungus in Hypoxylon section Papillata, subsection Papillata.

We suspect that B. exutans [º Diatrype exutans] belongs here. The holotype material at the Cooke herbarium of K has a white outer dehiscing layer and frequently short fusoid to pyriform ascospores. Unfortunately, the material is somewhat depauperate; we did not find asci or ascospores with cellular appendages. Moreover, we were unable to determine the configuration of different types of stromatal tissue. Miller (1961) misinterpreted the type specimen of Diatrype exutans and treated it as a variety of "Hypoxylon" nummularium. Thereafter, it has widely been applied to collections of B. capnodes with ascospore size ranges close to the upper limit.