鲁西地区寒武纪原始真牙形石分类方案的探讨  

A Taxanomic Study on Primitive Euconodonts

作　　者：武桂春[1] 姚建新[1] 纪占胜[1] 

机构地区：[1]中国地质科学院地质研究所

出　　处：《地质学报》2004年第3期289-295,i001,共8页Acta Geologica Sinica

基　　金：国家自然科学基金项目 (编号 40 3 0 2 0 0 2 )的资助成果

摘　　要：鲁西地区晚寒武世地层发育 ,产有数量丰富、分异度大的原始真牙形石分子 ,经笔者研究 ,建立了 2新属、2新种及 2未定种 Camconodontus rotundatus gen et sp.nov.,Camconodontus sp.,L aiwunodus lateron-odus gen et sp.nov.,L aiwunodus sp.;对 Dasytodus属进行了补充修订 ,建立了 1新种 Dasytodus posteronodus sp.nov.。这些属种的建立丰富了对已有原始真牙形石概念的认识。基于内部构造的观察 ,对原始真牙形石及部分易混淆的副牙形石进行正确的分类。以此为基础 ,分析、总结了这些分子外部形态上的差异 ,选用的分类原则和标准是从一般到特殊、特征明显程度逐渐降低 ,划分出了三类原始真牙形石和一类副牙形石 ,这在很大程度上简化了早期真牙形石分类研究的复杂性 。Primitive euconodonts are extrmely abundant and varied in the Late Cambrian in western Shandong Province. Two new genera are established, including Camconodontus gen. nov. and Laiwunodus gen. nov. Among them the following species are described: Camconodontus rotundatus gen. et sp. nov., Camconodontus sp., Laiwunodus lateronodus gen. et sp. nov., and Laiwunodus sp.. In addition, the Genus Dasytodus is emended, with Dasytodus posteronodus sp. nov. being added. The discovery of new species has greatly enriched and deepened the already known concept about primitive euconodonts. The study of the internal structure of conodonts faciliatates the differentiation among primitive euconodonts as well as part of paraconodonts more correctly. Together with the internal struture, some important morphological characteristics are selected. Three types of primitive euconodonts and one type of paraconodonts easily confused with each other are differentiated, making the complexity on primitive euconodont taxa greatly simplified. And this work will bring much convenience to further studies on other related problems.

关 键 词：晚寒武世 原始真牙形石 副牙形石 鲁西地区 生物地层划分 

分 类 号：Q911.6[天文地球—古生物学与地层学]