Two new species of the genus <i>Lecidella</i> (<i>Lecanoraceae</i>, <i>Ascomycota</i>) from maritime Antarctica, southern South America and North America

Two new species of the genus Lecidella, one with a North American-maritime Antarctic distribution and one with a so far exclusively southern South American-maritime Antarctic distribution, are described using molecular and morphological tools. Lecidella ayazii is a species growing on soil and also on mosses and has so far been found on the Antarctic Peninsula, as well as in the alpine areas of the La Sal Mountains, Utah, USA and in the Kivalliq Region (Nunavut) in the north of Canada, whereas L. drakensis occurs mainly on siliceous rocks, rarely on mosses, and has been recorded on both sides of the Drake Passage in southern Patagonia and the Antarctic Peninsula. Phylogenetic analysis of the nrITS sequence data shows that both species belong in the L. elaeochroma clade, each forming a highly supported and distinct group. Furthermore, they also differ in morphological and chemical characters from the species described so far in this clade. In addition, five further accessions were recorded from the maritime Antarctic, which were placed in the cosmopolitan and heterogeneous L. stigmatea clade, of which one could be assigned to the bipolar species L. siplei.