First fossil evidence of samaras of Ventilago Gaertn.(Rhamnaceae)from India and its implications  

作　　者：Taposhi Hazra Sampa Kundu Subir Bera Tapan Chakraborty Mahasin Ali Khan 

机构地区：[1]Palaeobotany and Palynology Laboratory,Department of Botany,Sidho-Kanho-Birsha University,Ranchi Road,Purulia,723104,India [2]Centre of Advanced Study,Department of Botany,University of Calcutta,35,BC Road,Kolkata,700019,India [3]Geological Studies Unit,Indian Statistical Institute,203,B.T.Road,Kolkata,700108 West Bengal,India

出　　处：《Journal of Systematics and Evolution》2023年第6期1079-1090,共12页植物分类学报（英文版）

基　　金：The authors are thankful to DST-SERB,GOl(File no.CRG/2020/001303)for their financial assistance.

摘　　要：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.

关 键 词：Himachal Pradesh INDIA Jharkhand palaeophytogeography Ventilago winged fruits 

分 类 号：Q94[生物学—植物学]