The lichens of Marion and Prince Edward Islands

A total of 100 lichen species are listed for the islands. Six species are described as new to science: Arctomia subantarctica Ovstedal, Arthothelium evanescens Ovstedal, Coccotrema stellata Ovstedal, Ramonia subantarctica Ovstedal, Thelocarpon subantarcticum Ovstedal and Verrucaria umbilicata Ovstedal. Four new combinations are made: Amandinea subplicata (Nyl.) Ovstedal, Poeltinula cerebrinella (Nyl.) Ovstedal, Verrucaria nigra (Mull. Arg.) Ovstedal (from Cape Horn) and Verrucaria tesselata (Dodge) Ovstedal (from Heard Island). One third of the islands' lichen species also occur in the Northern Hemisphere. Of the Southern Hemisphere species, 24 are exclusively known from areas to the east of the islands (Kerguelen Province Islands, Australia, New Zealand, contrasting to only six species recorded exclusively to the west (South Georgia, Antarctic Peninsula). This suggests a distribution against the present predominantly westerly winds. The large number of seemingly endemic species Is suggested to indicate the incomplete knowledge of the lichen floras of the sub-Antarctic Islands.