TWO NEW CONIFERS FROM THE EARLY CRETACEOUS OF THE RAJMAHAL BASIN, INDIA: IMPLICATIONS ON PALAEOECOLOGY AND PHYTOGEOGRAPHY

Abstract

The occurrence of a diverse range of conifers and bennettitales is characteristic of the macroflora from the early Cretaceous of the Rajmahal Basin, India. In the present paper two new conifer taxa assigned to the families Cupressaceae and Podocarpaceae are described from the intertrappean sediments of the Rajmahal Formation in Jharkhand State. The remains are silicified, composed of sterile and fertile shoots, detached leaves and dispersed seeds. The specimens have been placed under the family Cupressaceae, are described as Hirandubia cupressoides gen. et sp. nov., a species that shows close affinity with the extant cupressaceous genera Platycladus Spach and Chamaecyparis Spach, and provides the first comprehensive record of Cupressaceae from the Early Cretaceous of India. Elatocladus-type shoots and detached leaves have also been recovered. In association with the shoot fragments and detached leaves, a new kind of podocarpaceous dispersed seed designated as Podocarpospermum podocarpoides sp. nov., occurs together with a microsporangiate cone Podostrobus rajmahalensis (Rao) Rao and Bose, having in situ bisaccate pollen grains. These remains are all attributed to the family Podocarpaceae and have some similarities to extant Podocarpus L’Herit ex Pers. Based on the occurrence of a diverse range of conifers and bennettitales in the Early Cretaceous flora of Rajmahal Formation interpretation palaeoecology and palaeogeography has been done