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New coniferophyte ovulate structures from the Early Permian of China
Authors:BAOYIN GENG  JASON HILTON
Institution:Department of Paleobotany, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing 100093. P. R. China.
Abstract:Recent research on the Cathaysian flora of the Early Permian Shanxi Formation in Henan Province, southern China has led to the identification of a new kind of fertile shoot system of spermatophyte affinity, Loroderma henania gen. et sp. nov. From its morphological arrangement it is evident that this structure shares many similarities with known fossil coniferophyte taxa, although this particular combination of characters is unique, leading to the creation of a new genus and species. The fertile shoot system possesses a primary axis with helically arranged bract/shoot complexes, each consisting of a single lanceolate bract with parallel venation (indistinguishable from Cordaites sp. and Rufloria sp.) with an ovulate cone in its axil. Ovulate cones consist of an elongate and recurved axis which in approximately its distal half bears scales and ovulate sporophylls. Each ovulate cone bears 1–3 ovules of the Cardiocarpus organ genus within the confines of the cone, although the precise nature of their attachment is unclear. The presence of shared character states with various extinct taxa has made it difficult to assign it unambiguously to any existing coniferophyte order or family as they are currendy envisaged, with most likely affinities with or intermediate to the Vojnovskyales and Coniferales.
Keywords:Conifery  Cordaitales  Vojnovskyales
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