The origin of angiosperms has been tantalizing botanists for centuries. Despite the efforts of palaeobotanists, most of the pre-Cretaceous angiosperms are regarded either non-convincing or misdated. The applications of SEM and LM (light microscope) enable us to recognize a coalified fossil plant, Xingxueanthus sinensis gen. et sp. nov., from the Haifanggou Formation (Middle Jurassic, >160 Ma) in western Liaoning, China. Xingxueanthus is an "inflorescence" with more than 20 female units spirally arranged. Each female unit is situated in the axil of a bract. The female unit is composed of an ovule-container and a style-like projection at the top. There is a vertical column bearing several ovules in the ovule-container. The general morphology and the internal structure of Xingxueanthus distinguish itself from any known fossil and extant gymnosperms, and its structures are more comparable to those of angiosperms. Xingxueanthus, if taken as a gymnosperm, would represent a new class, demonstrate an evolutionarily advanced status of ovule-protection in gymnosperms never seen before, and provide new insights into the origin of angiospermy. Alternatively, if taken as an angiosperm, together with Schmeissneria, it would increase the diversity of Jurassic angiosperms, which has been underestimated for a long time, and suggest a much earlier origin of angiospermy than currently accepted.
A new kind of marattialean raches are reported from the coal balls in Coal Seam No.7 in the upper part of the Taiyuan Formation(early Early Permian) from Taiyuan,Shanxi,China and are assigned to the genus Stipitopteris Grand'Eury(Psaroniaceae) . The present specimens are different from all six reported species of the genus,and are therefore proposed as a new species:Stipitopteris shanxiensis. The raches of the new species are generally dorsi-ventrally attened. The main raches usually exhibit scales of different forms on their surface. Beneath the epidermis is a zone of parenchymatous cells,some of which contain tannin-like contents. Inside this is a zone of small sclerenchymatous cells. Inward are the ground tissue and vascular bundles. The vascular bundles are continuous and are in two circles:the outer circle assumes a transversely elliptical shape with the gap and pinna trace,and the inner circle assumes a shallow C-shape with inrolled ends. The ground tissue located at the inner side of the vascular bundle is composed of thicker-walled parenchymatous cells. The cells of the ground tissue are vertically elongated in longitudinal sections. Subordered raches are smaller and have simpler structures than the main raches. The parenchyma zone beneath the epidermis is thinner,usually one to two cells wide and the sclerenchyma zone is usually absent. The scales are poorly developed and there is only one C-shaped vascular bundle. The new species is comparable to the crosiers of Psaroniaceae of the Euramerican Flora in some aspects,for example,it has a dorsi-ventrally attened rachis and scales on the surface of the rachis. However,the other features and the preservative conditions of the present specimens indicate that they are not crosiers,but fully developed or mature raches. The new species is the first well-studied anatomically-preserved rachis of Psaroniaceae from the Cathaysian Flora and bears significance not only in understanding the anatomy and taxonomy of Psaroniaceae in the Cathaysian Flora,but also in the re
Ning XiangShi-Min MaBao-Lin TianShi-Jun WangMing-Shan Zhang
