FOSSIL IMPRINT • vol. 74 • 2018 • no. 3–4 • pp. 327–333 (formerly ACTA MUSEI NATIONALIS PRAGAE, Series B – Historia Naturalis) PLANT DIVERSITY OF THE MID SILURIAN (LOWER WENLOCK, SHEINWOODIAN) TERRESTRIAL VEGETATION PRESERVED IN MARINE SEDIMENTS FROM THE BARRANDIAN AREA, THE CZECH REPUBLIC MILAN LIBERTÍN 1, JIŘÍ KVAČEK1,*, JIŘÍ BEK2, PETR ŠTORCH2 1 Department of Palaeontology, National Museum, Prague, Václavské náměstí 68, 110 00 Prague 1, the Czech Republic; e-mail:
[email protected],
[email protected]. 2 Institute of Geology of the Czech Academy of Sciences, v.v.i., Rozvojová 269, 165 00 Prague 6, the Czech Republic; e-mail:
[email protected],
[email protected]. * corresponding author Libertín, M., Kvaček, J., Bek, J., Štorch, P. (2018): Plant diversity of the mid Silurian (lower Wenlock, Sheinwoodian) terrestrial vegetation preserved in marine sediments from the Barrandian area, the Czech Republic. – Fossil Imprint, 74(3-4): 327–333, Praha. ISSN 2533-4050 (print), ISSN 2533-4069 (on-line). Abstract: Plant mega- and microfossils are described from the middle Sheinwoodian of the Barrandian area. The material comes from the Loděnice locality and the same horizon as the earliest unequivocal land plant, Cooksonia barrandei LIBERTÍN, J.KVAČEK, BEK, ŽÁRSKÝ et ŠTORCH. Its age (432 Myr) is inferred from the associated graptolite fauna, including the zonal index graptolite Monograptus belophorus. Megafossils have clear similarity with Cooksonia, due to their dichotomised axes with slightly widened subtending axes bearing putative sporangia. They document some of the plant diversity that was in place when the fi rst proven representative of the genus Cooksonia appeared, and together with dispersed spores they provide strong and important evidence that a diversifi ed terrestrial ecosystem had developed on the Barrandian volcanic archipelago in the peri-Gondwanan realm by the end of the Sheinwoodian Stage of the Silurian Period.