Early Cretaceous flora of India–A review

Abstract

Earth’s terrestrial ecosystem during the early Cretaceous was marked by the dominance of naked seeded plants and appearance of flowering plants. Tectonic changes and evolutionary processes affected southern floras of the globe during this time. Review of Indian early Cretaceous flora distributed in peri and intra–cratonic basins signify homogenity of composition with regional variations. The flora composed of pteridophytes, pteridospermaleans, pentoxylaleans, bennettitaleans, ginkgoaleans, coniferaleans, taxaleans and taxa of uncertain affinity along with sporadic occurrence of flowering plants represent a unique Indian early Cretaceous flora. Similitude of basinal floras with marginal differences can be attributed to taphonomic limitations and taxonomic angularity. A perusal of available data brings out an opportunity for novelty in floral composition and variable associations dictated by prevailed environmental conditions. The eastern, western and central regions of India hold distinct litho units encompassing plant mega fossils represented by leaf, wood / axis, seed, fructification and associated marker forms. Remarkable tenacity of certain plant groups, which even found in modern flora and vulnerability of many taxa constitute a blend of extinct and extant. The appearance and extinction of certain taxa can be explained as a cumulative affect of evolutionary and climatic factors. Perpetuation of gondwanic floral elements during the early Cretaceous along with newly evolved floral components testifies evolutionary innovations and changing ecological constraints.