Two New Species of Eretmophyllum(Ginkgoales)from the Jurassic of Eastern Siberia  

作　　者：Andrey FROLOV Irina MASHCHUK 

机构地区：[1]Institute of the Earth's Crust,Siberian Branch of the Russian Academy of Sciences,Irkutsk 664033,Russia

出　　处：《Acta Geologica Sinica(English Edition)》2023年第4期1014-1025,共12页地质学报（英文版）

基　　金：carried out in the framework of the topic of the state task of the Institute of the Earth's Crust,Siberian Branch of the Russian Academy of Sciences(Project No.121042700218-2);this work involved the Centre of Geodynamics and Geochronology equipment at the Institute of the Earth's Crust(Grant No.075-15-2021682)。

摘　　要：Two new species of Eretmophyllum Thomas are described from the lower(Toarcian)and upper(Aalenian)Prisayan Formation of the Irkutsk Basin,Eastern Siberia,Russia based on distinct morphological and cuticular features of the leaves that distinguish them from other species of the genus.Eretmophyllum polypapillosum sp.nov.is characterized by the presence of 2-3 papillae on the lower and upper epidermis of ordinary cells.Taphonomically,the leaf burials of E.polypapillosum sp.nov.indicate that it preferred mesophilic forests developed on river terraces and/or low watersheds.Eretmophyllum yershowskiensis sp.nov.is represented exclusively by leaf cuticles extracted by coal maceration,and it probably inhabited the low banks of peat bogs.The presence of the genus Eretmophyllum in the Early Jurassic of France and Eastern Siberia shows that it was already widespread in the territory of Eurasia,distributed from Western Europe to Eastern Siberia.This indicates the possible existence of Eretmophyllum species elsewhere in the Early Jurassic such as Central Asia and Northwest China.

关 键 词：PALEOBOTANY ginkgoalean TAXONOMY paleophytogeography PALEOECOLOGY leaf cuticles Irkutsk Coal Basin 

分 类 号：Q914[天文地球—古生物学与地层学]