Anatomy of the peridium in the genus Nidula (Nidulariales, Basidiomycetes)

The anatomic structure of the peridia of the basidiocarps in species of Nid ula is described and illustrated. Fruit bodies were collected in the NW Pat agonian region of Argentina. In addition, the type specimens of Nidula cand ida (Peck) White and Nidula emodensis (Berk.) Lloyd and other collections f rom a herbarium were also examined. Different kinds of peridia were found, ranging from one-layered peridia to five-layered peridia. This suggests tha t the anatomic structure of the peridium in Nidula cannot be used as a gene ric taxonomic character as is the case with the other Gasteromycetes.