Status of gymnosperms in the Indian Tertiary flora

Abstract

Gymnosperms, the most dominated group of plants during Mesozoic, were meagerly represented in Indian Tertiary flora. The Tertiary gymnosperms occur in the form of petrified woods, cones and leaf impressions, besides pollen referable to the families Podocarpaceae, Araucariaceae and Cycadaceae. Until Late Cretaceous-Early Palaeocene the gymnosperms were widely distributed in the Indian peninsula. However, during Tertiary they declined to such an extent that towards the close of Pliocene Araucariaceae totally disappeared from Indian sub-continent. The podocarpaceae too, is now on the verge of extinction as it occurs in the restricted areas in northeast India and Nilgiri Hills in southern India. The cause of decline of these tropical gymnosperms and advent of the northern temperature members in the Indian subcontinent during Tertiary are discussed.