The diversification of the lynx lineage during the Plio-Pleistocene-evidence from a new small Lynx from Longdan, Gansu Province, China

A new small-sized lynx from Longdan, Gansu Province, China, Lynx hei sp. nov., is described in this study. The new species displays the characteristic Lynx generic traits, such as distinct buccal grooves in the upper canine, presence of an anterior groove in the upper canine, absence of upper premolar 2, and a moderately developed mastoid process, but it is markedly smaller than the previously described Lynx issiodorensis specimens from the same site and is also smaller overall than most living species, comparable to Lynx rufus in size. The new species has a relatively wide and deep zygomatic arch, similar to that of living Lynx lynx, Lynx pardinus and Lynx canadensis but wider than that of Lynx rufus. Our phylogenetic analyses suggest that Lynx hei falls within the crown group Lynx, being the sister to Lynx rufus or, less probably, a sister to Lynx issiodorensis + three other living species of Lynx. The Plio-Pleistocene Lynx issiodorensis is supported as the ancestor of Lynx lynx, Lynx pardinus and Lynx canadensis. Our phylogenetic study suggests that Lynx diversification over the Plio-Pleistocene was achieved initially by body size differentiation, putatively forced by intraspecific competition with other carnivorans, followed by morphological divergence.

Automated summary

A new small-sized lynx species has been discovered in Longdan, Gansu Province, China. This species differs from previously described lynx species in terms of size and certain traits. Phylogenetic analysis suggests that this new species is closely related to Lynx rufus or possibly Lynx issiodorensis and three other living lynx species. The study also suggests that the ancestor of Lynx lynx, Lynx pardinus, and Lynx canadensis is the Plio-Pleistocene Lynx issiodorensis. The diversification of lynx species during the Plio-Pleistocene was initially driven by body size differentiation.