Istchenkophyton filiciforme gen. et sp. nov., a new small vascular plant with thick cuticle from the Devonian of Voronezh Region (European Russia)

Remains of a new small vascular plant, Istchenkophyton filiciforme gen. et sp. nov., are described from the Upper Givetian strata of Pavlovsk vicinity (Voronezh Region). The plant is characterized by a very thick cuticle (up to 300 μm), complex branching pattern, similar to that of a frond rachis, anomocytic stomata, and a well-developed vascular bundle with a central elongated in transversal section protoxylem strand and massive metaxylem composed chiefly of scalariform bordered-pitted tracheids. A reconstruction of the new plant is proposed; its ecology and systematic position are considered. In the light of new data relationships of problematic Devonian plants with thick cuticle are discussed.