摘要
在云南腾冲上新统芒棒组中发现保存较好的植物分散角质层,共识别出7种:Reticutissolida,Reticutis tylotis,Fundicutis verriculis,Lusaticutis arizelis,Piliparicutis anfracta,Discrepoparicutis elongata,Enormicutis torquata,可归于6属,4亚类,4类,1个大类,表现出上叶角质层类型和下叶角质层类型的组合特征及上叶角质层类型的优先保存情况。从表皮细胞形态及气孔器等微观特征上看,具气孔的4种之间有着明显的差别,表明它们可能分别来自不同的母体植物;其中3种角质层的母体植物极有可能为被子植物,并处于优势地位。滇西当时温暖湿润的热带-亚热带、暖温带气候,为分散角质层的母体植物提供了良好的生存条件。而该区植物分散角质层的发现为分析其母体植物和重建古环境提供微体植物化石证据。
Seven species were recognized from the well preserved dispersed cuticles in the Pliocene of Tengchong, including Reticutis solida, Reticutis tylotis, Fundicutis verriculis , Lusaticutis arizelis , Piliparicutis anfracta , Discrepoparicutis elongate, Enorrnicutis torquata. They are referable to 6 genera, 4 Subturma, 4 Turma, 1 Anteturma. The species with stoma are more than those without stoma. In the assemblage of dispersed cuticles, L. arizelis, P. anfracta and D. elongata belong to the lower-leaf cuticle type, while R.solida, R. stylotis, F. verriculis and E. torquata belong to the upper-leaf cuticle type. Value of the upper leaf cuticle to lower leaf cuticle is higher than 100%, which indicates that the assemblage has undergone degradation and selective preservation of upper-leaf cuticle type. The cuticles with stomata, trichome and trichome base have taxonomically more important characters than other cuticle types, and are usually the only type of cuticles that can accurately be fidentified as leaf megafossils. Differences of L. arizelis, P. anfracta, D. elongata and E. torquata with stoma are obvious on microstructure characteristics of epidermis cells shape, stoma and trichome, which suggested that cuticles might be from different parent plants. The characteristics of cuticular thickenings on the guard cells, height of the stomatal poles and complex of trichomes are often used for determination of fossil angiosperm leaves. Parent plants of L. arizelis, P. anfracta and D. elongata might be angiosperm based on the characteristics mentioned above. It indicates that angiosperm plants might be dominant at that time. The warm and moist climate of Western Yunnan in a tropical-subtropical zone and warm temperate zone in the Neogene provided an appropriate living condition for the parent plants of the dispersed cuticles. The discovery of the dispersed cuticles also offered a mierofossil bais for parent plants analysis and palaeoelimate reconstruction at that time.
出处
《古生物学报》
CAS
CSCD
北大核心
2007年第1期113-121,共9页
Acta Palaeontologica Sinica
基金
国家自然科学基金(No.40372012
40502005)
教育部科学技术研究重点项目(No.404177)
现代古生物学和地层学国家重点实验室(中国科学院南京地质古生物研究所)基金(063101)资助项目
关键词
分散角质层
表皮构造
芒棒组
上新统
滇西
dispersed cuticles, epidermal structure, Mangbang Formation, Pliocene, Western Yunnan
