Gymnospermous woods from the Late Cenozoic sediments of Rajasthan, western India

Abstract

The paper describes two gymnospermous woods, namely Araucarioxylon Kraus, 1870 and Podocarpoxylon Gothan, 1905 from the Late Cenozoic sediments (Shumar Formation) of district Jaisalmer, Rajasthan, western India. The woods indicate favourable climatic conditions for the growth of mesic vegetation in Rajasthan till Plio-Pleistocene time compared to the xeric vegetation and drier conditions in the area today.

Two dicotyledonous woods from the late Neogene sediments of Jaisalmer, Rajasthan

“…Among these, two are being described herein. The described fossils belong to the Shumar Formation of Plio-Pleistocene age (Bhandari, 1999;Guleria & Shukla, 2011). The fossil assemblage of this formation was found similar to the wood assemblage recovered from the Kanakawati Series/Sandhan Formation (Plio-Pleistocene) of Kachchh (Biswas, 1965(Biswas, , 1971Biswas & Raju, 1973;Lakhanpal et al, 1984).…”

“…1). However, in view of its close lithological and plant fossil similarities with the Sandhan Formation of Kachchh, its age is considered as Plio-Pleistocene till more evidences are obtained (Guleria & Shukla, 2011). Although the two genera being described herein are already known from various Palaeogene and Neogene sediments of India (Prakash, 1966;Prasad, 1989;Guleria, 1990Guleria, , 1991Srivastava & Bande, 1992;Prakash et al, 1994;Tiwari & Mehrotra, 2000), this is their first record from this formation.…”

“…70º33' E) which is situated about 40-45 km northwest of Jaisalmer. The woods were found scattered on the top of Khuiala ridge, 3-5 km east of the Habur Village near Hema Ki Dhani (Guleria & Shukla, 2011). For the study of xylotomical characters, the woods were cut into thin sections, viz.…”

“…This tree also occurs in the Malayan Peninsula and Java. In addition, Mangifera indica L. (Guleria, 1984) and two gymnospermous fossil woods of Auracaria and Podocarpus of the families Auracariaceae and Podocarpaceae, respectively (Guleria & Shukla, 2011) are also known from this formation. The present distribution of all these modern counterparts of the described fossils indicates the existence of warm and humid conditions which might have supported the growth of semi-evergreen to deciduous forests in the area during the depositional time contrary to the present day harsh climate with xeric vegetation.…”

“…S o far, very few plant fossils have been described from the Shumar Formation (late Neogene) of Jaisalmer Basin in western India. Mangifera L. of the Anacardiaceae (Guleria, 1984) and two gymnospermous woods (Guleria & Shukla, 2011) are known from this formation. In order to reconstruct the palaeoclimate of the area, a number of fossil woods were collected from the late Neogene sediments of Jaisalmer.…”