A fusuline fauna is described from the base of the Heshan Formation in the Penglaitan Section, the GSSP for the base Lopingian Series. This fauna falls within the Clarkina guangyuanensis and Clarkina transcaucasica conodont zones, indicating an early Wuchiapingian age. A new genus, Laibinella, is established to include those species that are morphologically similar to but phylogenetically independent of Palaeofusulina. In total, three species from two genera can be recognized in the studied material: Laibinella tobensis (Zhang), Laibinella ellipsoidalis gen. et sp. nov., and Lantschichites minima (Chen). The Laibinella tobensis Zone is established for the early Wuchiapingian. Based on morphology and biostratigraphy, we infer the evolutionary lineages of Dunbarula–Laibinella in the early Wuchiapingian, and Dunbarula–Nanlingella in the late Wuchiapingian.