Specialized Adhesive Pad of a Climbing Pteridosperm from Permian Peat-Forming Forest (Wuda, Inner Mongolia)

Certain pteridosperm tendril adhesive pads are depicted from the Cathaysian flora of the Early Permian Taiyuan Formation of Wuda Coal-field in Inner Mongolia China. Specimens contain elliptical or rounded pads situating at the swollen tip of pinnule lobe tendrils which are highly comparable to those of the extant Parthenocissus tricuspidata in the way that both of them are similar in form and function. Specifically, information we have gained suggested that pteridosperms from the Permian might have performed a similar type of physiological process by producing some chemical substances which assisted them in climbing. The Wuda pteridosperm likely to climbed on Cordaites or Sigillaria trees. Moreover, physical principles such as the pressure difference between inside and outside of the pads also seems to play an important role in assisting climbing. The new finding indicates that some pteridosperms in the Permian Cathaysian flora possessed climbing growth habit as well as those in the Late Carboniferous Euramerica Flora, where climbing/scrambling growth habit is well known in the coal swamp forests. This finding shows one of the several earliest climbing habits in Cathaysia Flora and thus remarkably promotes our understanding of the growth habit of pteridosperm and the change in plant community structure in that area.

Late Paleozoic Floras of the Southern Hemisphere: Distribution, Composition, Paleoecology

The paleobotanical literature contains frequent references to paleofloristic regions (often called “floral provinces”) for the Late Paleozoic. Halle (1937) published an early map showing the distribution of four different floral associations in Asia, viz. the Glossopteris Flora, the Angara Flora, the European Permo-Carboniferous Flora and the Cathaysia Flora. Gothan and Weylan (1954) completed this map by adding information from different parts of the world. In 1962 Wagner published a general map showing a Permo-Carboniferous Equatorial Belt separating the northern hemisphere Angara Flora from the southern hemisphere Gondwana Flora. The diagrammatic representation by Meyen (1969) shows the increasing diversifications of these floras with geological time. A later version (Meyen in Chaloner and Meyen, 1973, and in Vakhrameiev, et al., 1978) shows an early differentation into two major units, i.e., the Arcto-Carboniferous Kingdom and the Gondwana Kingdom. The former would be subdivided into the Euramerican and Angara areas, to be distinguished from the Early Carboniferous onwards.