Two cycads Nilssonia mirovanae sp. nov. and Pseudoctenis babinensis J.Kvaček from the Cenomanian of the Bohemian Cretaceous Basin (the Czech Republic) as indicators of water stress in the palaeoenvironment
Abstract
Nilssonia mirovanae sp. nov. is described from the Late Cretaceous Cenomanian of the Bohemian Cretaceous Basin. It comes from the best-exposed portion of the Peruc-Korycany Formation, in the Pecínov quarry, west of Prague, the Czech Republic. Although preserved only as a fragment of a pinna, it clearly shows haplocheilic stomata. In this paper, we compare N. mirovanae with Pseudoctenis babinensis J.Kvaček from the same horizon. These two cycads have similar adaptations for surviving water stress: thick cuticles and sunken stomata, characteristic features among gymnosperms indicating adaptation to xeromorphic plants, cuticle analysis, Late Cretaceousdrought.