Notes on the maritime, lignicolous lichen Lecanora orae-frigidae

AbstractLecanora symmicta var. sorediosa Westman, a soraliate, yellow, crutose lichen frequently found on wood substrata along the sea shores in the arctic and boreal regions of the northern hemisphere, is now generally accepted as a distinct species, and has recently been provided with a new name: Lecanora arae-frigidae R. Sant. Besides usnic acid it contains zeorin, thiophanic acid and two accessory xanthones. The Finnish material of L. symmicta (Ach.) Ach. examined for comparison differs having thiophanic acid inconstant as well as three unknown substances, while lacking one of the xanthones. One specimen of L. orae-frigidae from the White Sea coast in Karelian A. S. S. R. was growing with a small thallus of Lecanora grantii Magnusson, a new record of the latter species for Europe.