Daldinia concentrica (Bolton: Fr.) Ces. & De Not.



Daldinia concentrica is constantly associated with Fraxinus and occasionally with other hosts. Both D. concentrica and Dpetriniae yield purplish pigments in KOH and have similar ascospore size ranges. The latter differs in having a simple conidiogenous branching pattern—ranging from Sporothrix-like to simple Nodulisporium-like, in having conidia produced from percurrently proliferating conidiogenous cells, and in having broader conidia. Most specimens of D. concentrica that we have examined have the stromatal surface cracked into a fine network. This feature has not been seen in D. petriniae.

Most of the listed synonyms are based upon ancient material that either could not be located or was not sought. The Robson specimen, although highly important, is not considered an epitype because it apparently does not bear ascospores. We here select specimen Whalley 838 as the epitype of Sphaeria concentrica.

The anamorph of D. concentrica has been described a number of times (see Table 1). Molliard (1904) proposed the name Nodulisporium tulasnei Molliard for it. Its conidiogenous structure has a Nodulisporium-like branching pattern as defined in Ju and Rogers (1996). However, the conidial dimensions given by different mycologists vary somewhat (see Table 1). The different substrates or media from which conidia were described may influence conidial dimensions. Many collections identified as D. concentrica, in fact, are not this fungus; thus, it is also probable that the variation in reported conidial dimensions is owing to the involvement of several taxa.

There is a curious report of D. concentrica from Poaceae (Farr et al., 1989). The specimen forming the basis for this report is D. bambusicola on alien quarantined bamboo (see SPECIMENS EXAMINED of D. bambusicola).

Table 1. Reported conidial dimensions from Daldinia concentrica.

Author(s) Conidial size range
Tulasne and Tulasne (1863) 6.5-8 x 5-6.5 mm
Jaczewski (1895) 6.5-8 x 5-6.5 mm
Molliard (1904) 7-8 x 4.5-5.4 mm
Brooks (1913) 6-8 x 3-4 mm
Bayliss-Elliott (1920) 6.5-8 x 5-6 mm
Miller (1928, 1930) 6-8 x 4-5 mm
Greenhalgh and Chesters (1968) 5-8.5 x 3-4.5 mm
Martin (1969b) 4.3-8.7 x 3.7-5 mm (ave. 6.3 x 4.1 mm)
Jong (1970) 5-10 x 3-4 mm
Whalley and Watling (1980) 4.5-8.5 x 3.5-5 mm
Petrini and Müller (1986) 6-8 x 4-5 mm
Van der Gucht (1994) (6-) 6.5-8.5 (-9) x 3-4 mm
Rogers et al.  (1999) (5.5-)6.5-8(-9) x 3.5-4.5mm