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The Ventilago Gaertn. (Rhamnaceae) is widely distributed in pantropical areas of Africa, Asia, and Australia. However, fossil records of this taxon are sparse, which limits understanding of the evolution and biogeographic history of the genus. In the present study, we report and describe two new fossil species of Ventilago, V. siwalika sp. nov. from the Miocene sediments of Himachal Pradesh, western Himalaya, and V. pliocenica sp. nov. from the Pliocene sediments of Jharkhand, eastern India based on single‐winged samaras. Ventilago pliocenica is characterized by a prominent midvein, obtuse to sub‐round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher‐order veins, the presence of equatorial rim, the hypanthium, and short pedicel. On the other hand, V. siwalika is characterized by a prominent midvein, obtuse to sub‐round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher‐order veins. Our discovery represents the first unambiguous fossil record of single‐winged samara of Ventilago from India and provides valuable insights into the evolution of this genus. In this paper, we also review its biogeographic history and add new information to understand its hypothetical migration route. Present and earlier records of Ventilago also suggest that this genus was a common forest element during Neogene (Miocene time) in Asia. [ABSTRACT FROM AUTHOR]

The Himalayan foreland basin originated through the India–Asia continent–continent collision driven by downward flexing of the Indian plate. It forms an ideal assemblage to delineate the role of process-controlled sedimentary fill in basin evolution. This paper provides the first comprehensive account of the lithofacies associations and architecture of the Middle Siwalik succession of the Himalayan foreland basin in the south-central Himachal Pradesh sector, India through detailed sedimentological analysis. Eight lithofacies form three distinct sand, gravel, and silt-mudstone lithofacies associations pertaining to specific depositional environments. Architectural elements have been defined together with bounding surfaces separating them. Sedimentological investigations reveal that the Middle Siwalik sequence represents a flash flood dominated piedmont fan and proximal to middle megafan. The fan expansion cycles indicate tectono-climatically controlled sedimentation in the Middle Siwalik foreland basin. Frequent flooding and a high sedimentation rate were influenced by the tectonic uplift along the reactivated thrusts in the hinterland coupled with phases of monsoonal intensification. • The studied Middle Siwalik belongs to a yet unattended Himachal sector of the Indian Himalaya. • Architectural documentation reveals different orders of fluvial hierarchy. • Sedimentation took place in the foreland basin setting solely by continental processes. • Contemporaneous piedmont fan and megafan sedimentary sequences are identified and interpreted. • The Middle Siwalik Foreland Basin of the present study is compared with foreland basins of similar tectonic settings globally. [ABSTRACT FROM AUTHOR]