Sponge spicules from the lower Cambrian in the Yanjiahe Formation, South China: The earliest biomineralizing sponge record
Sponge spicules from the lower Cambrian in the Yanjiahe Formation, South China: The earliest biomineralizing sponge record
复制标题
华南严家河组下寒武统海绵针：最早的生物矿化海绵记录
DOI：
10.1016/j.palaeo.2016.06.032
复制
发表时间：
2017-05-15
影响因子：
3
通讯作者：
Zhang, Lei
中科院分区：
文献类型：
--
作者：
Chang, Shan;Feng, Qinglai;Zhang, Lei
海绵是最早的后生动物，根据分子时钟，它的历史可以追溯到低温生代。然而，关于它们在埃迪卡拉纪-寒武纪界线下的生物矿化元素的记录一直存在争议。在这里，我们提出了第一个也是最早的无可争议的记录，在寒武纪最低的Terreneuian，在小壳化石Anabarites trisulcatus-Protohertzina anabarica组合带(带I)之下。中国南部湖北宜昌最低的阎家河组硅质岩中发现的针状体包括单轴体、双轴体、三轴体，其成分均为硅质。这种滤食后生动物造成的二氧化硅生物矿化的最早记录表明，海绵早在显生界开始时就对海洋系统中二氧化硅的循环做出了贡献。这些结果，以及对以前报道的海绵事件的回顾，表明了早寒武世海绵的两步演化。(C)2016爱思唯尔B.V.保留所有权利。
Sponges are the earliest metazoans, and according to molecular-clocks, have a deep history back into the Cryogenian. However, the record of their biomineralized elements below the Ediacaran-Cambrian Boundary has been controversial. Here we present the first and earliest indisputable record of hexactinellid spicules in the lowest Cambrian, Terreneuvian, below the small shelly fossil Anabarites trisulcatus-Protohertzina anabarica assemblage zone (Zone I). Spicules recovered from cherts of the lowest Yanjiahe Formation in the Yichang, Hubei province, South China, include monaxons, diaxons, triaxons, and that are all siliceous in composition. This earliest record of silica biomineralization by filter feeding metazoan suggests sponges have contributed to the cycling of silica in the oceanic system as early as the beginning of the Phanerozoic. These results, along with a review of previously reported sponge occurrences, suggest a two-step evolution on sponges of the early Cambrian. (C) 2016 Elsevier B.V. All rights reserved.