Leaf fragments of Herbifolia antiqua A.Frolov et Enushchenko gen.et sp.nov.from the Middle Jurassic(Aalenian)of the Irkutsk Coal Basin(Eastern Siberia,Russia)are reported.The following features are characteristic of H...Leaf fragments of Herbifolia antiqua A.Frolov et Enushchenko gen.et sp.nov.from the Middle Jurassic(Aalenian)of the Irkutsk Coal Basin(Eastern Siberia,Russia)are reported.The following features are characteristic of H.antiqua gen.et sp.nov.:the presence of leaf sheaths,linear smooth-edged leaves with parallel venation,anastomoses between the veins,anomocytic stomata,rhomb-shaped ordinary epidermal cells.Such a combination of characters is widespread in modern monocotyledonous plants and is absent in fossil and modern cryptogam and gymnosperms.Due to the lack of evidence of an enclosed ovule in H.antiqua gen.et sp.nov.,we attribute it to a typological angiosperm,based on its unique leaf structure characteristic of monocotyledons.The leaf epidermal structure of Herbifolia gen.nov.is most similar to those of modern Asparagales and Liliales.展开更多
基金carried out in the framework of the state task topic of the Institute of the Earth’s Crust,Siberian Branch of the Russian Academy of Sciences (Project No. 0346-2018-0004)involved the Centre of Geodynamics and Geochronology equipment at the Institute of the Earth’s Crust,Siberian Branch of the Russian Academy of Sciences (Grant No. 075-15-2021-682)
文摘Leaf fragments of Herbifolia antiqua A.Frolov et Enushchenko gen.et sp.nov.from the Middle Jurassic(Aalenian)of the Irkutsk Coal Basin(Eastern Siberia,Russia)are reported.The following features are characteristic of H.antiqua gen.et sp.nov.:the presence of leaf sheaths,linear smooth-edged leaves with parallel venation,anastomoses between the veins,anomocytic stomata,rhomb-shaped ordinary epidermal cells.Such a combination of characters is widespread in modern monocotyledonous plants and is absent in fossil and modern cryptogam and gymnosperms.Due to the lack of evidence of an enclosed ovule in H.antiqua gen.et sp.nov.,we attribute it to a typological angiosperm,based on its unique leaf structure characteristic of monocotyledons.The leaf epidermal structure of Herbifolia gen.nov.is most similar to those of modern Asparagales and Liliales.
