| Title | DENGLONGIA HUBEIENSIS GEN. ET SP NOV., A NEW PLANT ATTRIBUTED TO CLADOXYLOPSIDA FROM THE UPPER DEVONIAN (FRASNIAN) OF SOUTH CHINA |
| Authors | Xue, Jinzhuang Hao, Shougang |
| Affiliation | Peking Univ, Sch Earth & Space Sci, Key Lab Orogen Belts & Crustal Evolut, Beijing 100871, Peoples R China. |
| Keywords | Late Devonian Frasnian South China Cladoxylopsida Iridopteridales Rhacophyton NEW-YORK-STATE VENEZUELA ANATOMY ANEUROPHYTALES MORPHOLOGY YUNNAN |
| Issue Date | 2008 |
| Publisher | international journal of plant sciences |
| Citation | INTERNATIONAL JOURNAL OF PLANT SCIENCES.2008,169,(9),1314-1331. |
| Abstract | Denglongia hubeiensis gen. et sp. nov. is described from the Late Devonian Huangjiadeng Formation (Frasnian) of Hubei Province, South China. Main axes and two orders of lateral branches are recognized. The main axis is nodose and has a ridged surface, with a preserved length of up to 34 cm. Four to six first-order branches, sterile or fertile, are inserted at nodes of the main axis in a whorled pattern. Dense aerial roots occur at basal nodes of main axes, and sparse ones occur at some nodes of first-order branches. Some first-order branches bear only ultimate appendages; others bear ultimate appendages proximally and then in turn bear whorls of second-order branches distally, with an internode length of 40-60 mm. Sterile ultimate appendages are alternately or suboppositely borne on proximal portions of sterile first-order branches. One or two pairs of umbrella-shaped fertile structures are borne at the same position as sterile appendages but on fertile first-order branches. Second-order branches occur in whorls, with three or four at each node, and bear only sterile ultimate appendages. The fertile structure has an initial dichotomy that forms two sister components, each with lateral branches alternately arranged in a pinnate pattern. Each lateral branch dichotomizes several times, bearing small, fusiform sporangia in clusters of two to four on short branchlets along the inner side of the lateral branch. The plant is anisosporous. It is referred to a new genus and species, D. hubeiensis gen. et sp. nov. Its similarity to and divergence from iridopterid-cladoxylopsids, Rhacophyton, progymnosperms, and related plants are discussed. At present, Denglongia is assigned to Cladoxylopsida sensu lato in view of an iterative architecture and whorled organotaxis. |
| URI | http://hdl.handle.net/20.500.11897/311316 |
| ISSN | 1058-5893 |
| DOI | 10.1086/591987 |
| Indexed | SCI(E) |
| Appears in Collections: | 地球与空间科学学院 造山带与地壳演化教育部重点实验室 |
