New findings of gymnosperms in the Middle Jurassic of the East European platform

Abstract

The plant-bearing layers in the Stoilensky open mine (Belgorod Region, Russia) are dated to the middle Bathonian–early Callovian based on the dinoflagellate cysts and spore-pollen assemblages, and in the Mikhailovsky open mine (Kursk Region, Russia) – to the middle–late Bathonian based on palynological data. Representatives of Pseudotorellia are recorded in the Middle Jurassic of the Belgorod and Kursk regions for the first time. A new species, Pseudotorellia oskolica, is described from the Stoilensky open mine based on the unique morphological and epidermal features. Leaves of this species are very narrow, they are characterized by the presence of stomata on the adaxial leaf surface. The type material of Czekanowskia europea from the Middle Jurassic of the Pripyat depression in Belarus was restudied. The diagnosis for C. europea is provided, since only a description of this species was given in the original publication. Czekanowskia leaves are recorded from the Belgorod and Kursk regions for the first time. They are determined as C. europea based on the similar epidermal features as in the type leaves. A shoot of Pagiophyllum sp. and numerous leaf fragments of Podozamites sp. were found in association with C. europea in the Pripyat depression. These genera are recorded in Belarus for the first time. Findings of Pseudotorellia, Czekanowskia and Podozamites leaves in the Middle Jurassic floras of the East European platform are discussed.