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通过对华南上扬子区5条出露完好的剖面(下奥陶统-上奥陶统底部)进行几丁虫样品的系统采集、分析与研究,鉴定几丁虫24属128种.对5条剖面的几丁虫资料进行复合,综合分析几丁虫多样性及其演变,对华南上扬子区早奥陶世至晚奥陶世初期几丁虫的多样性事件提出新的认识:早期几丁虫出现(特马豆克中期),Euconochitina symmetrica的出现及几丁虫的初次辐射(特马豆克晚期),几丁虫再辐射及复杂多样化纹饰构造特征的出现(弗洛晚期)以及几丁虫分异度的高峰期(桑比初期).将研究区早奥陶世至晚奥陶世初期几丁虫的多样性演变与区内三叶虫、笔石、腕足类、牙形类、疑源类以及区外波罗的板块、冈瓦纳板块北部、劳伦板块及全球的几丁虫多样性曲线进行比较分析,可以看到:(1)华南奥陶纪各海洋生物门类多样性演变呈“幕式”发生,一般可识别出比较显著的2~3次多样性峰值,但各门类的辐射型式与规模各具特色;(2)华南与冈瓦纳北部的奥陶纪几丁虫辐射轨迹更为相似,二者的关系相较其他板块更为紧密;(3)奥陶纪几丁虫演化可划分为4阶段,即特马豆克期起源、弗洛期至大坪期稳步辐射、达瑞威尔晚期至凯迪初期辐射高潮以及凯迪晚期的分异度急剧下降.
The system of chitin samples was systematically collected, analyzed and studied in five well-exposed sections (Lower Ordovician-Upper Ordovician bottom) in the upwelling sub-region of South China, and 128 species of 24 genera Section of the chitin data composite, a comprehensive analysis of the diversity and evolution of chitin, the upper reaches of South China from the Early Ordovician to early Late Ordovician chitin diversity events put forward a new understanding: the early chin (Emergence of midterm Tebrak), emergence of Euconochitina symmetrica and initial irradiation of the bug (Late Temasek), re-emergence of the chitin and the presence of complex and diverse ornamentation (late Flore) The peak period of spermatozoa differentiation (initial period of Sangbei). The evolution of diversity of chitinies from early Ordovician to late Ordovician in the study area was compared with that of trilobites, penoliths, brachiopods, , The suspected sources, and the Baltic patches outside the region, the northern Gondwanaland plate, the Lauren patches and the diversity curves of chitin in the world. We can see that: (1) Sexual evolution was “curtain ” occurred, can generally identify more significant 2 to 3 times the diversity of peaks (2) The radiation pathways of Ordovician chitingensis in southern China and Gondwana are more similar, the relationship between the two is more similar than that of other plates; (3) The evolution of Ordovician chimpanzee can be divided into four stages, that is, the origin of the Temasek period, the steady radiation from the Floyd to the Daping phase, the radiant high from Darriwill to the early Katy and the sharp decline of the late Katydissessment.