Thin section observations have revealed a large amount of filamentous cyanobacteria from the dolomite of Cambrian Series 2 Xiaoerblaq Formation in the northwestern Tarim Basin. Specifically, four species belonging to three genera of Oscillatoriaceae fossils have been identified, including Obruchevella meishucunensis, Oscillatoriopsis longa, Oscillatoriopsis sp., and Siphonophycus typicum. These findings represent the first report of such filamentous cyanobacteria in the Xiaoerblaq Formation, and provide an exquisite preservation of their clear threelayer structure, that is, calcified mucilaginous sheath, organic tube wall, and internal black filament, augmenting the knowledge of their internal structure and identification characteristics. The discovery of Oscillatoriaceae fossils greatly increases the diversity of the Xiaoerblaq Biota and provides new materials for further study of fossils and the evolution of life in the early Cambrian.

通过岩石切片观察, 在新疆塔里木盆地西北缘寒武纪第二世的肖尔布拉克组白云岩中发现大量丝状蓝菌化石, 共鉴定出可归入颤藻目的丝状蓝菌类化石3属4种, 包括Obruchevella meishucunensis, Oscillatoriopsis longa, Oscillatoriopsis sp.和Siphonophycus typicum, 均为肖尔布拉克组内的首次发现。化石保存精美, 可以观察到Obruchevella内清晰的三层结构, 即钙化的胶质鞘、有机质的管体壁和管内黑色丝状物, 对这类化石的内部结构和鉴定特征起到补充作用。此次发现的颤藻化石丰富了肖尔布拉克组的生物多样性, 为塔里木盆地的化石研究和生命演化研究提供了新材料。