广西靖西地区寒武系芙蓉统果乐生物群腕足动物研究

The Burgess Shale-type Konservat-Lagerstätte, the Guole biota, had been found in Jingxi county, Guangxi province, filling the gap between the Middle Cambrian and the Lower Ordovician Burgess Shale-type Lagerstätte. Brachiopoda, as one of the abundant fossil phyla among the Guole biota, is the essential object to study. Firstly, the project intends to improve the research on calcareous brachiopods (articulated brachiopods) from the Guole biota based on preliminary research. Secondly, the project intends to improve the systematic taxonomy research of phosphatic-shelled form brachiopods (inarticulated brachiopods) from the Guole biota, which are poorly known. Thirdly, the project would try to discover new type of brachiopods and figure out the overall appearance of the Guole brachiopod. Further, the project would compare different brachiopod faunas with the Guole Brachiopod and reveal the feature, trend and law of the Late Cambrian brachiopod evolution. In the end, combined with other co-living fossil types of the Guole biota, the project intends to use the morphology of the Guole brachiopod to reveal the living mode of the Guole brachiopod and the palaeoecological background and factor behind it and tries to provide some evidences for the research of the Cambrian Evolutionary Fauna and the research of the origin of the Palaeozoic Evolutionary Fauna.

广西靖西地区寒武系芙蓉统果乐生物群的发现，有效填补了全球寒武纪中期—奥陶纪早期之间缺失布尔吉斯页岩型特异性埋藏化石库的空白。腕足动物作为其中数量丰富的生物类型，是必不可少的研究重点。本项目拟在果乐生物群腕足动物现有研究基础上，进一步完善碳酸钙质壳腕足动物（传统有铰类）的研究，对研究程度较低的果乐生物群磷酸质壳腕足动物（传统无铰类）开展深入的系统分类学研究，同时探索果乐生物群中可能存在的新属种腕足化石，厘清果乐生物群中腕足动物的整体面貌。在此基础上，对比果乐腕足动物与其它寒武纪早期-奥陶纪早期腕足动物，阐明寒武纪晚期腕足动物演替的特点、趋势和规律。结合果乐生物群中其它伴生生物类群，剖析果乐腕足化石形态特征所反应的腕足生活模式和古生态环境对其的制约因素，为寒武纪演化动物群以及古生代演化动物群的开启和起源研究提供依据。

本项目通过大量的野外工作和室内研究，对新采集的果乐生物群化石标本进行了古生物类群统计，量化了果乐生物群中各生物类群的综合面貌。统计研究发现，果乐生物群中腕足动物数量最多，占比50.2%；三叶虫次之，占比37.2%；软舌螺和棘皮动物分列第3和第4，占比分别是9.7%和2.1%，其他物种数量稀少，较为罕见。. 本项目以寒武纪晚期果乐生物群中的腕足动物化石为主要研究对象，详细统计了果乐生物群中腕足动物及三叶虫各属种的分异情况。本项目研究共发下腕足动物6属8种，包括3个新属种。3个新属种分别是：Eoobolus jingxiensis sp. nov.，Diandongia jingxiensis sp. nov. 和 Palaeobolus yunnanensis sp. nov.。其他属种分别是Palaeobolus jingxiensis, Billingsella guangxiensis, Billingsella costata, Guoleella lata, Palaeostrophia jingxiensis 和 Plectotrophia imparicostata。其中，Palaeostrophia jingxiensis 物种数量最多，占比高达61%，为优势物种。Eoobolus jingxiensis sp. nov. 物种数量居第二，占比26.3%。Billingsella 属共发现了两个物种，其中Billingsella costata 占7.9%， Billingsella guangxiensis 占2.8%，其他属种数量稀少，占比较小。总体来看，果乐生物群腕足动物种数量丰富，分异度明显。但具体到各属种，数量差别很大。. 本项目还开展了详细的果乐腕足动物系统分类学研究，对新采集的6属8种腕足动物（包括3个新属种），进行了详细的系统古生物学研究和描述，进一步揭示了果乐生物群中腕足动物的整体面貌。为后续进行全球寒武纪晚期生物群对比研究奠定了良好基础。