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

ABSTRACT

A 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).

KEYWORDS:

• Palmoxylon
• anatomy
• fibrovascular bundle
• Deccan Intertrappean Beds
• Maastrichtian–Danian
• Madhya Pradesh

Acknowledgments

M.K. and K.M. gratefully acknowledge the Department of Botany, Sidho-Kanho-Birsha University and Centre of Advanced Study (Phase-VII), Department of Botany, University of Calcutta for providing infrastructural facilities to accomplish this work. S.B. acknowledges the Centre of Advanced Study (Phase-VII), Department of Botany, University of Calcutta for providing necessary facilities. We are thankful to Dr Tapas Kumar Gangopadhyay, Sr Geologist, Indian Institute of Engineering Science and Technology (IIEST), Howrah and Kaustav Roy for help and cooperation during collection of fossil specimen.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Mahasin Ali Khan

Mahasin Ali Khan is a researcher and assistant professor at the department of Botany of Sidho-Kanho-Birsha University, India. He collected fossil specimens from the field, studied literatures and conceived the plan of work. He also interpreted the data and prepared the manuscript.

Kakali Mandal

Kakali Mandal is a researcher at the department of Botany of Sidho-Kanho-Birsha University, India. She carried out the anatomical and comparative study of fossil wood specimen and prepared selected parts of the manuscript.

Subir Bera

Subir Bera is a researcher and professor at the department of Botany of Calcutta university, India. He guided the entire course of this research and scrutinized and refined the manuscript as a senior author.