Xinjiangoxylon Gen.Nov., a New Gymnosperm from the Latest Permian of China

Following the greatest known end-Permian mass extinction plants have low diversity. Lycopsids and conifers dominated on land. A new gymnosperm Xinjiangoxylon gen. nov. is proposed based on a woody stem specimen collected from the Upper Permian （latest, Changhsingian） Upper Guodikeng Formation of the Taoshuyuan section, Turpan, Xinjiang Uygur Autonomous Region, Northwest China. The decorticated stem is characterized by a complex pith, endarch primary xylem and a thick secondary xylem cylinder. Numerous petrified woods were found in the Changhsingian at this section. However, there are rare wood fossils in the Early Triassic. The abrupt decrease of fossil woods worldwide relates to the crisis at the end of the Permian. Xinjiangoxylon turpanense gen et. sp. nov. appears to represents one gymnosperm that existed in the latest Permian.     

潮水盆地孢粉组合特征、时代及对比

对潮水盆地侏罗系陆相含煤地层由下而上建立了五个孢粉组合带,在组合三建立了两个亚组合。① Cyathidites-Chasmatosporites-Disaccites组合 (J11)。② Cyathidites-Chasmatosporites-Cycadopites组合 (J31)。③ Cyathidites minor-Cycadopites typicus组合 (J12);上部： Cycadopites typicus-Cyathidites minor-Osmundacidites亚组合,下部： Cyathidites minor-Cycadopites typicus-Lycopodiumsporites亚组合。④ Cyathidites-Quadraeculina-Classopollis组合 (J32)。⑤高含量 Classopollis组合 (J13)。