摘要
湖南界岭微体植物群由５６属１４５种（含１３新种）小孢子及很少量的疑源类与虫牙组成，并以Ｓｐｅｌａｅｏｔｒｉｌｅｔｅｓｈｕｎａｎｅｎｓｉｓ的百分含量最高（２６．８％）和同时含泥盆纪与石炭纪双重时代色彩的分子Ｒｅｔｉｓｐｏｒａｌｅｐｉｄｏｐｈｙｔａ，Ｒ．ｃｒａｓｉｃｕｌａ与Ｃｏｒｄｙｌｏｓｐｏｒｉｔｅｓｐａｐｉｌａｔｕｓ，Ｓｐｅｌａｅｏｔｒｉｌｅｔｅｓｐｒｏｔｉｏｓｕｓ为特征，但其地质时代属晚泥盆世晚期或晚法门期。
The origin and early evolution of vascular plants has long been one of the most interesting topics among botanists. To be sure, to solve this kind of problem depends obviously first of all on the discovery of relevant megafossil plants. Nevertheless, dispersed spores have unnegligible meaning and potential value in this regard. The record of Silurian spores has been successively accumulated and attracted much attention from the palaeobotanical circle since the end of the fifties. However, little has been known about the Silurian spores in China. Gao (1981) reported, without illustration, several forms including Leiotriletes, Retusotriletes, Ambitisporites and Apiculiretusispora from the “Wenlock” Wenxiang Formation in Dushan, S. Guizhou. Recently, Fang Zong jie et al. (1994) mentioned that they discovered some spores from the Late Silurian Yulongsi Formation in Qujing, E. Yunnan and named them the Apiculiretusispora spicula Emphanisporites neglectus assemblage. Rather diverse spores have also been reported from the Late Silurian Wutublak Formation in the Junggar Basin, N. Xinjiang, including Ambitisporites avitus, A. dilutus, Archaeozonotriletes chulus var. nanus, Synorisporites libycus and Retusotriletes warringtonii (Gao, 1981; Cai et al., 1993). The well known Hanjiadian Formation which outcrops at Dongkala, Fenggang County, N. Guizhou (Text fig. 1) is famous because it contains the possible vascular plant Pinnatiramosus qianensis Geng (1986). The “Wenlock” age of this formation was doubted by some palaeobotanists (e. g. Edwards, 1990) for the complexity of internal structure in this peculiar plant. In December 1991, one of the authors (Wang, Y.) and several colleagues from the Nanjing Institute visited the locality to make more detailed biostratigraphic investigation and systematical collection of fossils and rock samples for palynological study. The samples immediately beneath the chitinozoan bearing bed have proven to be palyniferous. Based on the characteristics of the spore assemblage (with 12 species or forms of 5 genera) and especially the chitinozoans, brachiopods and bivalves, the Hanjiadian Formation is most possibly of the Early Silurian (late Llandoverian-Telychian) age. The chitinozoans, brachiopods and bivalves mentioned below were identified by Geng Liang yu, Rong Jia yu and Fang Zong jie of NIGP respectively, while the field work was done with the help of Cai Chong yang, Fang Zong jie of Nanjing Institute, and Zhang Ji hui of Guizhou Institute of Geological Survey. To all these colleagues the authors wish to express their sincere thanks. The authors are also grateful to Gordon, D. Wood (Houston, USA) for his suggestions and technical comments.
出处
《古生物学报》
CAS
CSCD
北大核心
1997年第2期187-216,共30页
Acta Palaeontologica Sinica
关键词
邵东段
微体植物群
晚泥盆世
湖南
spores,origin of vascular plants,late Llandoverian,Fenggang County of Guizhou
