Yangquanoxylon miscellum gen. nov. et sp. nov., a gymnospermous wood from the Upper Pennsylvanian-lower Permian Taiyuan Formation of Yangquan City, Shanxi Province, with reference to the palaeoclimate in North China

A silicified gymnospermous wood, Yangquanoxylon miscellum gen. nov. et sp. nov., is described from the Upper Pennsylvanian-lower Permian Taiyuan Formation, Yangquan City, Shanxi Province, North China. The pycnoxylic wood is composed of thick-walled tracheids and thin-walled rays. It is characterized by mixed radial tracheid pits, uniseriate and homogeneous rays, occurrence of scalariform radial pitting, and various types of cross-field pitting. There are four types of cross-field pitting in Y. miscellum gen. nov. et sp. nov., including simple, taxodioid, phyllocladoid, and araucarioid. The absence of growth rings within fossil woods described here and reported previously from North China suggests a humid climate with minimal precipitation variations during the Late Pennsylvanian-early Permian.