A tropical rainforest biome once existed in India at the K-Pg: Evidence from ‘one-vessel’ arecoid palms

Here, we report ‘one-vessel’ palms (only one metaxylem vessel in each fibrovascular bundle (fvb) throughout the whole stem section) in considerable numbers from the latest Maastrichtian (Late Cretaceous)-earliest Danian (early Paleocene) (c. 67–64 Ma) sediments of the Deccan Intertrappean beds of Madhya Pradesh, central India. Detailed study of the anatomy of these fossil stems reveals the presence of ground parenchyma and sustained growth, lacunose ground parenchyma cells, and the presence of appendicular parenchyma connecting two fvbs, demonstrating their affinity with extant Cocos-type palms belonging to the sub-family Arecoideae. Based on the modern distribution of ‘one-vessel’ modern palms, we suggest that the discovery of ‘one-vessel’ palms from Deccan Intertrappean beds of Central India points to a tropical rainforest existing there during the Late Cretaceous to the early Paleocene.