陕南寒武系下部宽川铺组帽球状化石  

A SPHERICAL HAT-SHAPED ORGANISM FROM THE LOWER CAMBRIAN KUANCHUANPU FORMATION

作　　者：张金 郝欣 胡滢 杨晓光 王星[1] 姚肖永[2] 沈阳[3] 韩健[1] 

机构地区：[1]西北大学地质学系大陆动力学国家重点实验室及陕西省早期生命与环境重点实验室,西安710069 [2]长安大学地球科学与资源学院,西安710054 [3]中国地质大学(北京)博物馆,北京100083

出　　处：《古生物学报》2017年第4期415-424,共10页Acta Palaeontologica Sinica

基　　金：国家自然科学基金(项目编号41621003;41772010);现代古生物学和地层学国家重点实验室(No.163107);中央高校基本科研业务费(310827171013)资助

摘　　要：陕南寒武纪早期宽川铺组微体球状化石类型多样,如何正确辨别这些球状化石的生物属性是当前早期生命演化古生物学研究中的一个难点。我们在宽川铺组中发现了一类为数众多,具有一个或者多个不规则的帽状隆起结构以及翻边帽沿的帽状化石。研究表明这些帽状化石均为不完整的个体,其完整形态呈不规则的凹球形。根据帽球状化石帽身的数量和相对位置,这类化石可划分为"单帽型"、"双帽型"和"复帽型"三种类型。这些凹球状化石呈双层壳壁,内壁光滑,外壁粗糙。因为凹球状化石形态及其表面小孔与微体藻类、后生动物的胚胎以及壳体化石差异都非常显著,所以推测这类化石可能与带壳原生动物亲缘关系最为紧密。The phosphatized spheroidal in three dimensions from the Kuanchuanpu Formation in south are rather abundant. Generally, fossils preserved early Cambrian Shaanxi, China, they are inter- preted as metazoan embryos and microscopic algae, but some of them remain controversial in affinities. Here we report a kind of or sub-spherical shelly fossils characterized by one, two or more deep concaved, hat-shaped structures within a sub-sphere frame. Most incomplete specimens appear to be hat-shaped structure with a brim on account of taphonomic transportation and abrasion. We subdivided these fossils into single-hat, double-hat and complex hat types. There is no septum between adjacent primary or secondary hat-shaped structures within an individual. The shell wall consists of a smooth inner and a coarse outer layers. The fossil differs from co-occurring algae, metazoan embryos and other shelly metazoans, but is interpreted tentatively here as a tested proto- zoan.

关 键 词：帽球状化石 宽川铺生物群 原生动物 宽川铺组 寒武纪早期 

分 类 号：Q915.2[天文地球—古生物学与地层学]