AN UNUSUAL PSYCHROPHILIC AQUATIC AGARIC FROM ARGENTINA

Gloiocephala aquatica sp. nov. is described from material collected ne ar Esquel, Chubut, Argentina. It forms tiny acystidiate basidiomata th at arise from circular pseudosclerotial plates and develop a lateral s tipe, smooth hymenophore, and gelatinized tissues. The species grows o n submerged culms of California bulrush in the littoral zone of eutrop hic lakes and ponds, and develops its basidiomata and sporulates under water, often beneath a thin layer of ice. The psychrophilic aquatic ha bit of G. aquatica is unique in the Agaricales.