A new species of Eirictis (Mammalia, Carnivora, Mustelidae) from Lower Pleistocene of Yuanmou Basin, Yunnan, China

The Yuanmou Formation has long been appreciated for producing abundant Pleistocene fossil mammals in South China, especially several families of large carnivores. The discovery of a new locality in the South of Yuanmou County recently provided substantial evidence of new Pleistocene predators. Among them, a small mandible and the associated P4 and M1 of a Lyncodontini mustelid were found in Member 3 of the Yuanmou Formation (1.7–2.6 Ma) and are described in this study. Eirictis zhangi n. sp. confirms the first presence of Eirictis in Southeastern Asia. This species is characterized by its smaller mandible and maxilla, a unique parallelogram-like M1 with the musteline pattern. We also present a brief stratigraphy and palynological analysis of the new fossil locality, which provide evidence for the rapid change of climate and vegetation, and further support the connection of the Yuanmou Basin and North Chinese localities. Our study provides new insight into the early hominid occupation in South China, valuable for further excavation of this critical section and fauna.