Type studies of sequestrate Russulales. I. Generic type species

Holotypes of the type species of the genera of sequestrate Russulales (Arca ngeliella, Cystangium, Elasmomyces, Gymnomyces, Macowanites, Martellia, and Zelleromyces) were studied. Characters used to define genera were re-exami ned and several were found to be of little or no use at the generic level. The structure of the peridiopellis proved to be more stable than other char acters used previously to define genera in the sequestrate Russulales. Prop osed realignments include (i) merging Martellia into Gymnomyces, (ii) mergi ng Elasmomyces into Macowanites, and (iii) redefining the boundaries of Gym nomyces and Cystangium.