A SYNOPSIS OF THE GENUS CLADONIA IN THE NORTHWESTERN UNITED-STATES

Fifty-seven taxa in the lichen genus Cladonia ave known from the United States west of the Rockies. Approximately 20% of the taxa are endemic to the area. All of the major worldwide infrageneric groups, viz. sections Cladonia, Cocciferae, Helopodium, Perviae, and Unciales, ave represented. Some of the taxa previously considered to be widespread in the region are narrowly distributed. The Cascade Mountains are the major biogeographical boundary in the region, with several taxa found exclusively on one side or the other of the mountains. Two new species, C. andereggii Hammer sp. nov. and C. extracorticata Hammer sp. nov., are recognized.