Pleistocene Hedgehog Mesechinus (Eulipotyphla, Mammalia) in China

Since the 1920s, fossil erinaceids have been found in several dozen Quaternary localities in China. Previously, most of them were provisionally classified in eurytopic Erinaceus. This limits understanding of the authentic diversity and evolution of Erinaceinae in China and the reconstruction of their paleohabitats. We reviewed all accessible erinaceid fossils found in the Quaternary deposits in China. An erinaceid fragmentary mandible collected from the early Pleistocene deposits in Tianzhen county, Shanxi Province in North China was classified as Mesechinus cf. hughi, which is the oldest definite report of fossil Mesechinus in China. We considered that Erinaceus koloshanensis Young and Liu (1950) from Geleshan, Chongqing Municipality, should be transferred to Mesechinus as M. koloshanensis, and E. olgae Young (1934) from Zhoukoudian, Beijing, should be considered as a synonym of M. dauuricus. Our re-examination supplies a fossil calibration for the previous molecular phylogeny of the Erinaceinae. The earliest Mesechinus appeared in the early Pleistocene with the representative Mesechinus cf. hughi, M. dauuricus occurred in the middle Pleistocene and Erinaceus amurensis is also dated to the middle Pleistocene. Compared with Erinaceus, Mesechinus occupies a narrower niche and could be a potential indicative genus for a woodland or forest environment.