Cuticles of the Polish type material of Cordaites palmaeformis (Göppert) Weiss and a Cordaites principalis-like form from Germany, Pennsylvanian

The epidermal characteristics of Cordaites palmaeformis are described based on its type material. A lectotype has been selected based on Göppert's material (syntypes) from Wałbrzych, Intrasudetic Basin, Poland [late Bashkirian (early Westphalian) age]. The holotype of Cordaites principalis from the Saale Basin of Germany [Gzhelian (Stephanian C) age] does not allow the study of cuticles and this species name is retained for specimens from which cuticles could not be obtained. Specimens with Cordaites principalis-like venation from the same strata and basin are described as Cordaites principaloides Å imůnek, sp. nov. based on their cuticles. Cuticles of both species (Cordaites palmaeformis and C. principaloides) are amphistomatic and are of the same type. Stomatal complexes are formed by two guard cells, two lateral and two polar subsidiary cells and, in both species, are arranged in stomatal rows on the adaxial and abaxial sides of the leaves. However, there are differences in the shape of these cells. Cordaites palmaeformis has very thin and indiscernible anticlinal walls, whereas Cordaites principaloides has wide and prominent anticlinal walls. The otherwise identical cuticular structure seen in these two species has not been previously observed.