Paleocene flora from Seymour Island, Antarctica: revision of Dusén's (1908) pteridophyte and conifer taxa

The Paleocene flora from Seymour Island, Antarctica, first collected by Nordenskjöld on the Swedish South Polar Expedition (1901–1903), was described by Dusén (Citation1908) as having 87 leaf taxa making it one of the most diverse floras of this age in the Southern Hemisphere. The original descriptions of these leaf impressions included 37 pteridophytes and one conifer. Many species identified by Dusén were based on single fragmentary specimens. Major new collections housed at the British Antarctic Survey (Cambridge, UK), together with the original collections held at The Swedish Museum of Natural History, form the basis for a taxonomic revision of the flora. This paper concentrates on the pteridophytes and conifers. The diversity is considerably reduced from Dusén's estimates with just three ferns (Cladophlebis aemulans, Cladophlebis seymourensis, Sphenopteris angustiloba) and two conifers (Araucaria imponens, Elatocladus seymourensis) recognized.