Late Cretaceous plant mesofossils from Table Nunatak, Antarctica

Abstract

Charred and structurally preserved plant remains have been recovered from Late Cretaceous strata from Table Nunatak, Antarctica. The mesofossils, up to a few mm in length, represent structures from lycopods (megaspores), ferns (circinate rachides), conifers (wood, leaves, leafy shoots, pollen cones, microsporophylls, ovulate cone scales, seeds), and angiosperms (leaves, flowers, fruits, seeds). This work focuses on the megaspores, microsporophylls, ovulate cone scales and vegetative structures. The mesofossils were extracted from unconsolidated sediments deposited in a shallow-marine environment during the late Santonian (ca. 83 Ma). The Table Nunatak assemblage is the only known Cretaceous mesofossil assemblage with charred plant parts from Antarctica, and one of only a few from the Southern Hemisphere as a whole. It represents the remains of forests that grew at palaeolatitudes of 65°S, during a time in the Cretaceous in which high latitude environments experienced warm temperate climates in a global greenhouse world.