Placynthium glaciale

Placynthium glaciale is a species of saxicolous lichen in the family Placynthiaceae. Found in Alaska, it was described as a new species in 2020 by lichenologists Alan Fryday and Toby Spribille. The type specimen was collected in the Hoonah-Angoon Census Area of Glacier Bay National Park, on the upper end of Muir Inlet. Here the lichen was found growing on an argillite-like boulder as well as exposed cobbles in post-glacial soil. The specific epithet glaciale  alludes to its association with glacial forelands.