Taxonomic and palaeobiological implications of a large, pathological sabretooth (Carnivora, Felidae, Machairodontinae) from the Lower Pliocene of South Africa

Abstract

We describe the most complete postcranial remains of a pathological, large‐bodied sabretooth from the Lower Pliocene site of Langebaanweg ‘E’ Quarry (South Africa). The skeleton consists of hind limb and vertebral elements that exhibit distinctive exostoses, osteophytes and eburnation. We performed a quantitative morphological comparison of the new postcranial remains found in Langebaanweg, with other Neogene and Quaternary sabretooth and non‐sabretooth felids, consisting of the genera Amphimachairodus, Machairodus, Lokotunjailurus, Dinofelis, Panthera, Homotherium and Smilodon from several sites in Africa, Europe and North America, using principal component analysis and Mosimann transformations. Although the pathological deformation of the remains distorted some of the linear measurements, most of the analysed variables do not contain pathological features, and strongly indicate that the Langebaanweg sabretooth is morphologically closer to Machairodus aphanistus and Lokotunjailurus emageritus than it is to Amphimachairodus giganteus. This indicates that the remains could belong to an undetermined sabretooth species from the Langebaanweg locality. The observed pathologies in the foot and lumbar spine are consistent with diagnostic criteria for severe osteoarthritis (due to maturity), which would have limited limb mobility with severe consequences for hunting success.