First report of the Pingding locality of the Balang Lagerstätte (Cambrian Stage 4), South China: Implications for community complexity and geographic variation

Abstract

Exceptionally preserved fossil deposits provide detailed information on fossil assemblages and critical data that illustrate the complexities of Cambrian marine ecosystems. The Balang Lagerstätte (Cambrian Stage 4), one of the important biotas from the slope facies of Guizhou Province, yields diverse and abundant well–preserved fossils distributed across a variety of fossil localities. Here we present the first report of a new soft–bodied fossil assemblage from the Balang Formation in Pingding Village, Majiang County, outside the area from which soft–bodied fossils were previously known to occur. This new fossil site contains a variety of exquisite fossils including sponges, chancelloriids, cnidarians, hyoliths, brachiopods, arthropods, priapulids and vetulicolians. Compared with other Balang localities, the Pingding fossil assemblage is a brachiopod-dominated palaeocommunity with diverse arthropods. Results of a detailed comparative study indicate that the Balang localities are highly heterogeneous in fossil composition. In addition, the discovery of this new locality bridges the environmental gap between the offshore and slope palaeoenvironments, and offers a unique opportunity to investigate the factors responsible for differences in palaeocommunity composition. In general, these findings illustrate great community complexity in the Balang Lagerstätte which reflects ecospace utilization along an environmental gradient in the aftermath of the Cambrian Explosion.