Delineations of forest fungi: Morphology and relationships of vararia

Summary

Vararia belongs in a group of hymenomycetes characterized by non-xanthochroic basidiocarps in which gloeocystidia are formed rather regularly. Basidia and gloeocystidia originate at a relatively deep level in a catahymenium or hyphidial hymenium; thus they are overgrown by continuing development of the hyphal elements. As a result, they may become deeply submerged in the structure of the basidiocarp, together with embedded basidiospores. Dichohyphidia are formed as dichotomously-branched structures of limited growth. Although commonly subulate, dichohyphidia may show a considerable range of form even within a single basidiocarp. In Melzer's iodine reagent they commonly exhibit a dextrinoid reaction by becoming reddish brown. Hyphae of basidiocarps and cultures of some species have clamp-connections; those of other species lack clamps. Spores of the various species may be fusoid-ellipsoid, ellipsoid, globose, or cylindric, and may have either prominent or obscure amyloid ornamentation or may be apparently non-amyloid. Together with cultural characteristics such as the presence or absence of oedocephaloid conidiophores and various hyphal modifications, the hyphal and spore characteristics of the basidiocarp seem to present a potential basis for division ofVararia into several subgenera or generic segregates. The preceding considerations form the basis for a discussion of the position and relationships ofVararia within the Aphyllophorales.