A taxonomic revision of crustose caliciod lichens and fungi occurring in the cool and temperate areas of South America comprising 47 species in 7 genera is presented. Most of the species are lichenized, have passive spore dispersal, and belong to Acroscyphus, Calicium and Cyphelium in Caliciaceae and Chaenotheca in Coniocybaceae. Species in Mycocaliciaceae, included in Chaenothecopsis, Mycocalicium and Phaeocalicium are also frequent. They are parasites or saprobes on vasculaI plants and algae, or comrnensalistic on lichens. A few species of Microcalicium in Microcaliciaceae also occur. These lichens and fungi have previously been very neglected in the area. Calicium isabellinum, Chaenotheca australis, C. confusa, Chaenothecopsis arthoniae, C. australis, C. cinerea, C. lecanactidis, Mycocalicium anomalum and Phaeocalicium fuegensis are described as new. Eleven further species are new to South America, and several species are new to Argentina and Chile. Most of the species occur in oldgrowth Nothofagus forests, and are like in other areas sensitive to forest exploitation. A high proportion of the species (74%) also occur in the Northern hemjsphere, only three (6%) species are austral, and eight (17%) are endemic.