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贵州丹寨南皋在寒武纪属于扬子板块深水相区,最近在该区寒武系下部牛蹄塘组中上部黑色泥页岩中发现了大量保存完好的海绵动物化石,共9属10种。文中描述其中比较典型的海绵动物化石5属5种:赫兹海绵未定种Hintzespongia sp.,杯形对角海绵Diagoniella cyathiformis(Dawson,1889),密集鬃毛状海绵Saeta-spongia densa Mehl and Reitner in Steineret al.,1993,大坪三岔五射海绵Sanshapentella dapingi Mehl and Erdt-mann,1994和羽状光芒海绵Solactiniella plumata Mehl and Reitner in Steineret al.,1993。在这套整体缺氧的黑色泥页岩中有如此多而完整的海绵动物化石的保存,可能是由于上涌洋流、水流或海平面的变化等导致短暂的充氧事件,加上多幕次的热水沉积,提供大量食料,从而利于需氧量相对较低的原始后生动物--海绵动物的大量繁盛。
Nangao, Danzhai, Guizhou Province belongs to the deep-water phase of the Yangtze Plate in the Cambrian. Recently, a large number of preserved sponge fossils were found in the upper black mud shale in the lower part of the Niutitang Formation in the area, . In this paper, five species of 5 genera of sponge animal are described: Hintzespongia sp., Diagoniella cyathiformis (Dawson, 1889), Saeta-spongia densa Mehl and Reitner in Steineret al 1993, Sanshapentella dapingi Mehl and Erdt-mann, 1994 and Solactiniella plumata Mehl and Reitner in Steineret al., 1993. The preservation of so many complete sponge fossils in this overall hypoxic black shale may have resulted from brief episodes of oxygenation due to upwelling ocean currents, changes in water currents or sea level, Of the hot water deposits, providing a large number of foodstuffs, thus contributing to the relatively low oxygen demand of primitive metazoan animals - a large number of prosperous animals.