Early Silurian (mid-Sheinwoodian) palynomorphs from the Loděnice-Špičatý vrch, Prague Basin, Czech Republic

Abstract

Dispersed spores, cryptospores, scolecodonts, acritarchs, prasinophytes and chitinozoans, dated by graptolites as being middle Sheinwoodian (early Wenlock, ca 432 Ma), are described from the Loděnice-Špičatý vrch locality, Prague Basin, Czech Republic. Palynomorphs were macerated from a specimen (stored in the National Museum, Prague), with fragments of Cooksonia sp. and the zonal index graptolite Monograptus belophorus giving precise stratigraphic position within Monograptus belophorus Biozone. Important is the oldest occurrence of monolete spores. The number of spore taxa indicate that minimally six types of early vascular plants and probably two to three types of cryptosporophytes grew on the Svatý Jan Volcanic Island in the Prague Basin. The ecology of the first cryptospore and trilete spore producers within Sheinwoodian–Přídolí interval is discussed with special focus on first two globally important key events (after Homerian glaciation and during Přídolí) for earliest vascular land plants. The combination of palynological and palaeobotanical records confirms important role of volcanic islands of the Prague Basin for the evolution of early land plants.