The late Paleocene to early Eocene Arctic megaflora of Ellesmere and Axel Heiberg islands, Nunavut, Canada

The late Paleocene to early Eocene sediments of Ellesmere and Axel Heiberg islands, Nunavut, of the Canadian High Arctic contain a rich fossil flora and fauna. Although the megafloral fossils have been known for more than a century, limited descriptions of the fossil flora have been presented. Here, we provide a comprehensive morphotype catalogue of fossil plants from multiple localities from Ellesmere and Axel Heiberg islands that form a systematic framework for establishing an early Paleogene polar flora from High Arctic latitudes in Canada. Described are 62 'dicot' angiosperm morphotypes, three monocotyledonous angiosperms, 13 gymnosperms, and five pteridophyte morphotypes. This work presents a significant contribution to the understanding of north-polar diversity and environments during the warm greenhouse climate of the early Paleogene.