Sinolejeunea yimaensis gen.et sp.nov.(Hepaticae) from the Middle Jurassic Yima Formation in Henan Province of China  

作　　者：YANG XiaoJu WU XiangWu 

机构地区：[1]Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China

出　　处：《Science China Earth Sciences》2011年第2期228-232,共5页中国科学（地球科学英文版）

基　　金：supported by Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KZCX2-YW-154);National Basic Research Programme of China (Grant No. 2006CB701400)

摘　　要：A new liverwort with perichaetium and perigonium collected from the Middle Jurassic Yima Formation is described. Gametopbyte is dorsivental, irregularly branched, bearing two-ranks of lateral leaves obliquely attached to main axis, and one rank of ventral leaves transversely attached to ventral surface of the axis. Lateral branch bearing perigonium arises from axil of ventral leaves. Perigonium consists of small paired perigonial bracts arranged in a spike. Two perichaetia are borne on the top of lat- eral branches with an ovate perianth bearing longitudinal ridges and grooves. Setae are thin and straight and stretch out from the aristulate perianth mouth. General morphology of this fossil bears resemblance to some living liverworts of Jungermanniales. It is so far the oldest fossil record of Jungermanniales in the world.A new liverwort with perichaetium and perigonium collected from the Middle Jurassic Yima Formation is described.Gametophyte is dorsivental,irregularly branched,bearing two-ranks of lateral leaves obliquely attached to main axis,and one rank of ventral leaves transversely attached to ventral surface of the axis.Lateral branch bearing perigonium arises from axil of ventral leaves.Perigonium consists of small paired perigonial bracts arranged in a spike.Two perichaetia are borne on the top of lateral branches with an ovate perianth bearing longitudinal ridges and grooves.Setae are thin and straight and stretch out from the aristulate perianth mouth.General morphology of this fossil bears resemblance to some living liverworts of Jungermanniales.It is so far the oldest fossil record of Jungermanniales in the world.

关 键 词：HENAN LIVERWORT Middle Jurassic Yima Formation 

分 类 号：P534.52[天文地球—古生物学与地层学] P618.110.2[天文地球—地质学]