A New Species in the Lecanora Subfusca Group Containing Usnic Acid in Addition to Atranorin

Abstract

Lecanora pseudogangaleoides spec. nov. is a saxicolous lichen in southeastern Australia. It fits anatomically into the L. subfusca group (=Lecanora s.str.), but differs from most previous concepts of that group in containing usnic acid in addition to atranorin. The presence of usnic acid is now considered to be of less importance in that group, and species containing usnic acid may well belong to Lecanora s.str. Within L. pseudogangaleoides chemical variation with respect to the presence of xanthones was observed and two subspecies are distinguished. Lecanora pseudogangaleoides s.str. lacks xanthones, whereas L. pseudogangaleoides subsp. verdonii subsp. nov. contains the arthothelin chemosyndrome in addition to the normal occurrence of the psoromic acid chemosyndrome. A key orthe distinction of L. pseudogangaleoides and similar species is included.