西藏拉萨早白垩世种子蕨一新种  

A NEW SPECIES OF PTERIDOSPERM FROM THE UPPER MESOZOIC OF XIZANG(TIBET)

作　　者：杨小菊[1] 李建国[1] 

机构地区：[1]中国科学院南京地质古生物研究所,南京210008

出　　处：《古生物学报》2016年第4期467-472,共6页Acta Palaeontologica Sinica

基　　金：中国科学院战略性先导科技专项(B类)(XDB03010103);国家自然科学基金(41472011)联合资助

摘　　要：描述发现于西藏拉萨晚中生代林布宗组的种子蕨化石,确定为新种——西藏叉羽叶Ptilozamites tibeticus Yang sp.nov.。该种有别于其它叉羽叶各种:叶二次羽状;末二次羽轴较粗,具斜向纵纹或瘤状突起;末次羽片披针形,在羽轴上互生;末次羽轴的表面具斜的纵条纹;小羽片在末二次羽轴和末次羽轴上互生至对生,排列规则而紧密。中生代种子蕨类植物主要发现于晚三叠世至早侏罗世地层,新种的发现表明种子蕨类植物在青藏高原可一直延续到早白垩世。The Mesozoic seed fern groups are especially significant, as it was believed that the progenitors of the angiosperms can be found in one of these groups （Taylor et al. , 2009）. Most records of the Mesozoic pteridosperms in China are from the Upper Triassic to the Lower Jurassic. While carrying on the field work on the Mesozoic in Xizang （Tibet） some new fossil materials were collected from the Linbuzong Formation in Lhasa, Xizang and a new species of pteridosperm was recognized. The plant revealed unusual forked, its pinnate morphology indicating a closer relationship with the genus Ptilozarnites Nathorst, 1878.

关 键 词：叉羽叶 种子蕨 早白垩世 西藏 

分 类 号：Q914[天文地球—古生物学与地层学]