A New Species of the Extinct Genus Schizolepis from the Jurassic Daohugou Flora,Inner Mongolia,China

来源 :Acta Geologica Sinica(English Edition) | 被引量 : 0次 | 上传用户:yiyong6698
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Schizolepis daohugouensis sp.nov.is described from the Jurassic sediments of Daohugou flora,from Ningcheng County,Inner Mongolia Autonomous Region,China.The female cone is slender,cylindrical in shape,seed scale complexes are loosely and helically arranged on the cone axis at intervals of 3-5 mm.The seed scales are bilobed and divided almost from the base;the scales have no evident petiole but an articulation at the region of attachment to the cone axis.Each lobe of the seed scales is oval in shape,widest at the lower middle part;lobes are obtusely pointed with entire margins.Bract scale is fan shaped.Based on the records of Schizolepis,this is the first report of the occurrence of female cone of Schizolepis with the seed scales,the winged seeds and vegetative branches preserved together in the Jurassic deposits.The new discovery provides evidence that confirms the phylogenetic position of Schizolepis to the extant Pinaceae. Schizolepis dahugouensis sp. Nov. Is described from the Jurassic sediments of Daohugou flora, from Ningcheng County, Inner Mongolia Autonomous Region, China. The female cone is slender, cylindrical in shape, seed scale complexes are loosely and helically arranged on the cone axis at intervals of 3-5 mm. The seed scales are bilobed and divided almost from the base; the scales have no evident petiole but an articulation at the region of attachment to the cone axis. Each lobe of the seed scales is oval in shape, widest at the lower middle part; lobes are obtusely pointed pointed with the entire margins.Bract scale is fan shaped.Based on the records of Schizolepis, this is the first report of the occurrence of female cone of Schizolepis with the seed scales, the winged seeds and vegetative branches preserved together in the Jurassic deposits. The new discovery provides evidence that confirms the phylogenetic position of Schizolepis to the extant Pinaceae.
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