First report of brachiopods with soft parts from the Lower Cambrian Latham Shale (Series 2, Stage 4), California  

美国加利福尼亚州寒武纪早期莱瑟姆页岩中发现软躯体保存的腕足动物

作　　者：Yue Liang Lars E.Holmer Yazhou Hu Zhifei Zhang 梁悦;Lars E.Holmer;胡亚洲;张志飞(State Key Laboratory of Continental Dynamics,Shaanxi Key Laboratory of Early Life&Environments,Department of Geology,Northwest University,Xi'an 710069,China;Department of Earth Sciences,Palaeobiology,Uppsala University,Uppsala SE-75236,Sweden)

机构地区：[1]State Key Laboratory of Continental Dynamics,Shaanxi Key Laboratory of Early Life&Environments,Department of Geology,Northwest University,Xi'an 710069,China [2]Department of Earth Sciences,Palaeobiology,Uppsala University,Uppsala SE-75236,Sweden

出　　处：《Science Bulletin》2020年第18期1543-1546,M0003,M0004,共6页科学通报（英文版）

基　　金：the National Natural Science Foundation of China(41720104002,41890844,41425008 and 41621003);the Strategic Priority Research Program of Chinese Academy of Sciences(XDB26000000);the Program of Introducing Talents of Discipline to Universities(D17013);Research of L.E.Holmer supported by the Swedish Research Council(VR Project No.2018-03390);a Zhongjian Yang Scholarship from the Department of Geology,Northwest University,China。

摘　　要：Exceptionally preserved faunas have greatly improved our understanding of animal origin and evolution,and systematic investigations of Cambrian sediments around the world during the last two decades have led to a dramatic increase in the num-bers of Konservat-Lagerstatten[1].美国加利福尼亚州寒武纪早期莱瑟姆页岩(Latham Shale,第二世,第四期)作为国际上著名的布尔吉斯页岩型化石库之一,以保存了大量精美的小油栉虫类(olenellids)三叶虫著称,同时伴有丰富的腕足动物和软舌螺类化石.但迄今未发现任何腕足动物软组织化石.本文报道了该化石库发现的软躯体保存的2个腕足动物属种——前瞻型神父贝(Paterina prospectensis)和意外迈克威仔贝(Mickwitzia occidens).前瞻型神父贝壳体边缘保存精细、排列致密、具长达7 mm的刚毛.刚毛呈细线状、红褐色,扫描电子显微镜分析发现保存为次生的莓状黄铁矿.前瞻型神父贝腕足动物的刚毛和壳体与布尔吉斯页岩中发现的底栖固着的神父贝十分相似,表明腕足动物神父贝中发现的拟态状底栖固着生活方式可以追溯到寒武纪第四期.意外迈克威仔贝壳体纹饰和向后排列的纤细刚毛与我国澄江化石库发现的东方日射水母贝(Heliomedusa orienta)极为相似.该发现表明干群类腕足动物迈克威仔类(Mickwitziidae)在劳伦大陆和泛冈瓦纳大陆的首现可能并不同时,很有可能迈克威仔类在寒武纪早期起源于包括我国华南在内的东冈瓦纳地区,随后开始向全球扩散.

关 键 词：CAMBRIAN California LOWER 

分 类 号：X70[环境科学与工程—环境工程]