Discovery of a petrified noeggerathialean strobilus,Discinites sinensis sp.nov.from the Permian of Shizuishan,Ningxia,China

A petrified strobilus Discinites sinensis sp.nov.is discovered from the Lower Permian of Shizuishan in Ningxia,North China.The epidermal cells of sporophyll are long and narrow,with both ends pointed.Each sporangium is ellipsoid,with the basal part contracted and short,thick sporangiophore-like.The cells of tapetum and sporangial walls are arranged longitudinally.The annulus is not developed.Mega- and microsporangia are similar in shape.They can hardly be distinguished unless they are broken,and the spores are exposed.In situ mega- and microspores are also similar in shape and both of the Deltoidospora type.The new species supports the systematic placement of Discinites within Noeggerathiales,and the progymnosperm affinity of the Noeggerathiales.