REEVALUATION OF HOHENBUEHELIA-NIGRA AND SPECIES WITH CLOSE AFFINITIES

Specimens tentatively determined as Hohenbuehelia nigra var. microspor a were found in the environs of Buenos Aires. Study of collections in BAFC identified by Singer as H. nigra showed that var. microspora diff ered considerably from var. nigra. This led to a study of the holotype s of H. nigra var. microspora and H. nigra var. nigra. In the present paper specimens of Hohenbuehelia nigra var. nigra (Schwein.) Singer ar e redescribed and compared with H. nigra sensu Singer and Digilio, and with H. subbarbata. The taxonomic position of H. nigra var. microspor a Singer is defined, for which the new name H. singeri is proposed, wh ereas for H. nigra sensu Singer and Digilio the variety H. nigra var. pileocystidiata is proposed.