Archaeocyaths were one of the major animal groups contributing to the Cambrian Explosion. Despite an overall poriferan appearance of their hypercalcified skeletons, they exhibit a number of peculiar features such as the presence of septa and an absence of spicules. This sets archaeocyaths apart from general trends in early poriferan evolution. Fossils recently discovered from the early Cambrian Guanshan Lagerstätte of South China exhibit features typical for the suborder Archaeocyathina whilst possessing a silicified skeleton associated with carbonaceous material. This rigid fibrous skeletal framework, on the other hand, fits the diagnosis of the supposed ancestral aspiculate demosponges, the family Vauxiidae. By a detailed description of this specimen and a direct morphological comparison between the Archaeocyathina and the Vauxiidae, we suggest that the supposed Cambrian representatives of horny demosponges, that is, vauxiids, probably, were a progeny lineage of archaeocyathines. They survived the extinction of hypercalcified archaeocyaths due to their ecological adaption to siliciclastic environments. The existence of hypercalcified dictyoceratid (‘keratosan’) sponge Vaceletia, well known as a ‘living archaeocyath’, supports such a possibility.

中文翻译：

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Vauxiids作为archaeocyaths的后代：一个假设

Archaeocyaths是促成寒武纪大爆发的主要动物群之一。尽管它们的高钙化骨骼的整体外观是多孔的，但它们表现出许多特殊的特征，例如存在隔膜和没有骨针。这使古菌与早期孔虫进化的一般趋势不同。最近从华南早寒武世关山Lagerstätte发现的化石表现出Archaeocyathina亚目的典型特征，同时具有与碳质材料相关的硅化骨架。另一方面，这种刚性的纤维骨骼框架符合假定的祖先尖状Demosponges 家族Vauxiidae 的诊断。通过对该标本的详细描述以及古木亚目和 Vauxiidae 之间的直接形态比较，我们认为，假定的寒武纪代表的角质demosponges，即vauxiids，可能是古蓝藻的后代谱系。由于它们对硅质碎屑环境的生态适应，它们在高钙化古菌的灭绝中幸存下来。存在高钙化的 dictyoceratid ('keratosan') 海绵Vaceletia，众所周知的“活的古菌”，支持这种可能性。