Middle Eocene flora of the Bering Island (Komandor Islands, North-eastern Asia)

Abstract

In this work, a securely dated middle Eocene plant fossil assemblage is described and illustrated. Plant fossils come from the volcanogenic-terrigenous deposits of the Tolstyi Cape Formation and Buyan Formation exposed in the east and south-east parts of the Bering Island, Komandor Islands (Commander Islands) group. They belong to conifers (four species) and dicotyledonous angiosperms (five species). A new combination Cupressinocladus napanensis (Budantsev) comb. nov. is described, a neotype and emended diagnosis for the species Dicotylophyllum beringianum (Chelebaeva et Akhmetjev) Budantsev and a later synonym for the species Macclintockia sabinae (Chelebaeva et Akhmetjev) Chelebaeva are proposed. The flora is shown to be most similar to the diverse late Eocene flora of Western Kamchatka. This, in turn, allows us to suppose that the Kamchatkan flora might be middle to late Eocene in age. It reflects coniferous-broadleaved deciduous vegetation existed in a wet temperate climate of northeast Asia.