海绵动物为最古老的后生动物类群之一, 海绵骨针化石在海绵动物研究中具有重要价值。本研究在广西三江地区寒武系清溪组三段灰岩中发现了大量海绵骨针化石, 对其进行了系统的分析, 揭示了不同类型海绵骨针的形态特征。研究结果表明, 清溪组三段中海绵骨针化石数量庞大, 种类多样, 尤其以双轴四射骨针为主, 占总数的85%以上。此外, 还发现有三轴五射、五轴五射等多种复杂形态的骨针, 并通过扫描电子显微镜(SEM)揭示了其内部的轴管截面结构特征, 通过能谱分析显示其元素组成主要为Si和O。通过对骨针的形态进行对比分析, 本文推测, 广西三江地区寒武系清溪组三段中海绵个体可能以十字形和X形海绵骨针组成的网格状结构为主要特征。本研究为寒武纪海绵骨针化石的分类与演化研究提供了新的材料。

Sponges (Porifera) are among the oldest metazoan groups, and their fossilized spicules are of great importance in sponge research. In this study, numerous sponge spicule fossils were discovered in a limestone layer of Member 3 of the Cambrian Qingxi Formation in the Sanjiang area, Guangxi, China. A systematic analysis was conducted to document the morphological characteristics of different types of these sponge spicules. The results indicate that the sponge spicules from Member 3 of the Qingxi Formation are abundant and diverse, with diaxonic tetractine spicules dominating and accounting for over 85% of the total. In addition, more complex forms, such as pentactines and orthotetraenes, were identified. Scanning electron microscopy (SEM) revealed the internal cross-sectional structures of axial canals within these spicules. Energy-dispersive X-ray spectroscopy (EDS) analysis showed that their elemental composition consists primarily of Si and O. Based on comparisons of morphological variations of these spicules, this study suggests that the sponges from Member 3 of the Cambrian Qingxi Formation in the Sanjiang area of Guangxi may have primarily formed grid-like structures composed of cross-shaped and X-shaped sponge spicules. These findings provide new data for the classification and evolutionary study of Cambrian sponge spicule fossils.

中国地质调查局地质调查项目(DD20230221)、自然资源部地层与古生物重点实验室开放课题基金(SP202501)、国家自然科学基金(42172037, 41702023)和广西地质矿产勘查开发局项目(GXDK202432)联合资助