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A number of specimens recently collected from the Early Permian Shanxi Formation of Wuda, Inner Mongolia demonstrate that the leafy shoot and strobilus of Tingia unita sp. nov. are both sprouting from a common stem, and consequently improve our understanding of the whole plant mor- phology of this enigmatic taxon of the Cathaysian flora. The strobili are cylinder-like, 1.7-2.5 cm in diameter and over 20 cm in length, with a basal stalk 7―8 mm in width and about 7 cm long. Sporophylls are verticillate, with approximately 8-10 in a whorl. On the adaxial side of each sporophyll a sporangium is attached. The strobilus is heterosporous and the microspores are of the Punctatisporites type. Large leaves vary from linear to oblong with entire lateral margins but are slightly lobed at the apex. Small leaves are generally the same as the large leaves but much narrower. The whole plant is probably a small arborescent tree with leafy shoots and strobili forming a crown, rather than a water plant with larger leaves floating on the surface of the water as previously understood. Features of the new species are in favor of the close affinity between Tingia Halle and Noeg- gerathiales, and accordingly the affinity of Noeg- gerathiales to Progymnospermophyta.  相似文献   
2.
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.  相似文献   
3.
Noeggerathiales are an extinct group of sporebearing plants of uncertain systematic position that are known from Carboniferous and Permian age Euramerican and Cathaysian floras that occurred in presentday Europe, North America, and East Asia. The order Noeggerathiales includes over 50 species of more than 20 fossil genera, but their paleoecology is not well understood yet. Previously this group had been found only in extrabasinal floras or those inhabiting clastic wetlands. Noeggerathiales have never been recorded in coal ball floras. Thus, it is up to now uncertain whether this group has contributed to the formation of coal. Recent investigations of an Early Permian peatforming flora of the Taiyuan Formation near Wuda, Inner Mongolia, which was preserved in a volcanic ash fall has provided evidence that noeggerathialean plants not only existed in the peatforming vegetation but could even be the dominant group in some areas of the coal swamp. The Noeggerathiales in this particular peatforming forest include Tingia unita, Paratingia wudensis, and a new species of Paratingia. Exceptionally well-preserved specimens indicate that these noeggerathialean plants are small trees with a canopy of compound leaves and strobili near the top of an unbranched (monocaulous) stem.  相似文献   
4.
A petrified strobilusDiscinites 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 theDeltoidospora type. The new species supports the systematic placement ofDiscinites within Noeggerathiales, and the progymnosperm affinity of the Noeggerathiales.  相似文献   
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