Based on a combined three locus analysis two new genera, Charcotiana and Amundsenia, are proposed in the lichen family Teloschistaceae, subfamily Xanthorioideae. Charcotiana includes the new species C. antarctica, which is known only from continental Antarctica. The bipolar genus Amundsenia includes the new species A. austrocontinentalis, which is also known only from continental Antarctica, and the Arctic species Caloplaca approximata which is here combined into the new genus. The two new genera are phylogenetically distinct, but poor in morphological characters; the new species consist mainly of minute apothecia in cracks of rocks located in the climatically harshest regions of the Antarctic. They are somewhat similar to another continental Antarctic species, Austroplaca frigida, which is described as a new name based on the illegitimate name Caloplaca frigida Søchting. The distribution of the four species is mapped

A new species of Shackletonia (Teloschistaceae) is described from the McMurdo Dry Valleys in Antarctica, one of the regions with the harshest conditions on Earth. Distinctive traits of the new taxon are the grey thallus, its black lecideine apothecia with a dark greenish blue exterior side of the exciple, Lecidea green pigment present at the cortex and exciple, emodin-dominated anthraquinones only in epithecium, and spores on average 11.2 × 6.0 μm with 3.6 μm wide septum. New chemical data from HPLC analyses further supports the uniqueness of the genus Shackletonia regarding secondary metabolite production within subfamily Xanthorioideae. Using three molecular markers (nrITS, nuLSU, and mtSSU) we found the new species sister to S. sauronii, a species so far known only from Livingston Island (Antarctica). Using secondary calibrations we inferred a long-time evolution of Shackletonia in the Southern Hemisphere, which separated from the remaining lineages of Xanthorioideae between the late Cretaceous and the early Paleogene, and diversified during the late Paleocene and early Oligocene.