Middle Miocene floras of Iceland - the early colonization of an island?

Author(s)
Fridgeir Grímsson, Thomas Denk, Leifur A. Símonarson
Abstract

Two macrofloras, 15 and 13.5 Ma old, are described from the oldest exposed plant bearing sediments on Iceland. Many of the taxa are mentioned for the first time and a lime tree, Tilia selardalense, is described as a new species. In case of the older flora, differences in the environment are reflected in plants derived from volcanic sediments from high elevations (Selárdalur, 15 Ma) and from lowland alluvial plains (Botn, 15 Ma). The former are characterized by zonal elements and dominated by Fagus. The latter is dominated by conifers inhabiting swamps and hummocks. The younger Ketilseyri flora (13.5 Ma) is poorer and more similar to the Selárdalur flora. Both floras suggest a humid warm temperate climate (mostly Cfa climate sensu Köppen) with a number of exotic elements (Glyptostrobus, Sequoia, Magnolia, Cercidiphyllum). Evaluating the dispersal mechanisms of all the taxa shows that at least some (Aesculus, Fagus) could not have possibly colonized Iceland crossing large ocean barriers. Furthermore, most anemochorous taxa recorded have a very limited dispersal radius. This suggests that when "proto-Iceland" was colonized, it was connected to the mainland or accessible via a chain of islands. This land could have been part of the Greenland-Scotland Transverse Ridge that is believed to have persisted from the early Cenozoic to Late Oligocene and partly into the Middle Miocene.

Organisation(s)
Department of Palaeontology
External organisation(s)
Nordic Volcanological Center - NordVulk, University of Iceland, Swedish Museum of Natural History
Journal
Review of Palaeobotany and Palynology
Volume
144
Pages
181-219
No. of pages
39
ISSN
0034-6667
DOI
https://doi.org/10.1016/j.revpalbo.2006.07.003
Publication date
05-2007
Peer reviewed
Yes
Austrian Fields of Science 2012
105117 Palaeobotany
Keywords
ASJC Scopus subject areas
Ecology, Evolution, Behavior and Systematics, Palaeontology
Sustainable Development Goals
SDG 13 - Climate Action
Portal url
https://ucrisportal.univie.ac.at/en/publications/2808f6ae-d5a4-47cf-842c-4b4864e64b19