A new species of permineralized palm stem from the Maastrichtian–Danian sediments of Central India and its palaeoclimatic signal

Abstract

ABSTRACTA new species of permineralized palm stem, Palmoxylon deoriensis Khan, Mandal et Bera, sp. nov. is described from the Late Maastrichtian (late Cretaceous) – Danian (early Paleocene) sediments of the Deccan Intertrappean Beds of Deori village in Dindori District, Madhya Pradesh, Central India. The fossil specimen is a stem, characterized by the presence of cortical, sub-cortical and central zones with dermal, sub-dermal and inner central zones. The common anatomical features observed in the dermal, sub-dermal and inner central zones are the presence of regularly dispersed fibrovascular bundles, reniforma type of dorsal fibrous sclerenchymatous part (dcap), usually one metaxylem vessel element in each fibrovascular bundle (fvb), both tabular and radiating parenchyma around fvb, leaf-trace bundles distinguished by their protruded tongue-like vascular part with protoxylem vessel elements and highly compact ground tissue with thick-walled parenchyma cells, and the absence of fibrous and diminutive vascular bundles as well as centrifugal differentiation of fibrous part of fvb. These anatomical characters reveal its affinities with the extant Cocos-type palm taxa belonging to the family Arecaceae. Presence of mostly one, large (diameter > 183 μm) metaxylem vessel in each fvb and absence of lacunar ground tissue in the present fossil specimen indicate that palms thrived under a tropical, terrestrial environment during the deposition time (Late Maastrichtian–Danian).