Collema coccophorum and Leptogium britannicum are classified as extinct (Ex), 16 species as endangered (E), 11 as vulnerable (V), 9 as in need of monitoring (V+), 18 as rare (R), 5 as indeterminate (I), and 7 as insufficiently known (K). Parmeliopsis esorediata is assigned to category A (special responsibility). Special maps summarize the distribution of all species within each of the categories E, V, V+, and R. Norway has European responsibility for 18 species and Fennoscandian responsibility for 55 species of macrolichens. Among the species included in the red list, Norway has the only or the main population for several species on a Fennoscandian (55 species), European (18), or world-wide basis (1).
Each species is described and discussed with respect to substrate and habitat preferences, threats, and status in Norway. For species known from more than five localities, maps indicate the status in each locality. A complete locality list is given for each species. Distributions in Fennoscandia, Europe and on a world-wide basis are briefly reviewed. Recommendations are given for conservation purposes.
Threatened macrolichens are concentrated in deciduous forests and woodlands along the southwestern coast, old-growth spruce forests in central Norway, and old-growth boreal forests and agricultural landscapes in eastern Norway.