First discovery of Megantereon skull from southern China

ABSTRACT The sabertoothed cat Megantereon is an iconic carnivore in the Pleistocene of Eurasia, yet its fossil record is extremely rare and highly fragmentary in southern China (and the whole Oriental Realm). Here we report a nearly complete and undeformed skull of Megantereon from Sabretooth Cave, Chongzuo, southernmost China, middle Early Pleistocene. The general morphology allows us to assign it to Megantereon nihowanensis, differing from the northern China population of M. nihowanensis by better developed P4 parastyle and longer c-p3 diastema. The excellent preservation allows us to exam the previous unrecognised cranial characters. Megantereon shows a clear affinity to Smilodon in many aspects, e.g. wide nasal with parallel lateral border and smoothly curved posterior border, presence of moderately developed antero-medial process of the nasal, presence of anterior accessory process of the frontal, and a distinct frontal depression behind the posterior border of the nasal. These characters are markedly different from those of Homotherium, suggesting a deep divergence of the two lineages of sabertoothed cats. The rarity of Megantereon in southern China and southeastern Asia probably suggests this genus is not well adaptive to the closed forest environment.