Occurrence of the Genus Pachypteris in the Triassic of India

Abstract

The leaf genus Pachypteris Brongniart occurs commonly in Mesozoic rocks throughout the world. In India, the genus has hitherto been known only from the Lower Cretaceous strata of Rajmahal, Jabalpur, Bhuj and Pariwar formations. However, a few specimens collected from the Janar River beds of Tiki Formation, in their gross features and cuticular details, evidently represent a new species of the genus. The species, named as Pachypteris hirsuta sp. nov., in addition to its obvious hypostomatic lamina, is characterized by the presence of polygonal trichome bases. Each trichome base is surrounded by a ring of radially elongated cells. From Janar River beds, species of Lepidopteris, Dicroidium, Xylopteris, Sphenobaiera and Baiera have been described earlier. Pachypteris is a further addition to this assemblage. On the basis of faunal and floral remains, Tiki Formation has been dated as Upper Triassic. Occurrence of Pachypteris is hereby recorded for the first time from Indian Triassic strata.