Occurrence of acrostichum linn., a coastal fern in the Tertiary sediments of Kasauli, Himachal Pradesh, north-west Himalaya

Abstract

A fossil fern frond resembling that of Acrostichum Linn, is described from the Kasauli sediments (Lower Miocene), exposed along Kalka-Shimla road between Kumar Hatti and Barong, Himachal Pradesh. This fern, being primarily coastal in its distribution, is highly significant from the view point of palaeoecology, phytogeography and depositional environment. It indicates near shore tropical conditions and tidal influence in the area during Early Miocene. This is the first megafossil record of Acrostichum from the Tertiary sediments of India.