Osteology and ecology of Megantereon cultridens SE311 (Mammalia; Felidae; Machairodontinae), a sabrecat from the Late Pliocene - Early Pleistocene of Senéze, France

Megantereon cultridens was a derived, Late Pliocene to Early Pleistocene sabrecat, and although fossils of animals referred to the genus and species have been found at several locations throughout Eurasia, most are fragmentary. However, the specimen SE311 from Senéze in France represents an almost complete and well-preserved skeleton, and this is only known from very few other sabrecats, thus providing a rare glimpse into the full anatomy of an unusual and derived sabrecat. In this monograph, we provide a complete overview of the anatomy of Megantereon cultridens SE311, and compare it with extant large felids, and the few other derived sabrecats from which ample fossil material is known, although most frequently representing several specimens. SE311 was a large specimen of M. cultridens and would have had a body mass of 100–110 kg and a head–body length or around 160 cm, which is similar to a small lioness or large male jaguar. Megantereon sp. were sexually dimorphic, and the size of SE311 suggests that it was a male. As with several other derived sabrecats, it was powerfully built, and had particularly robust forequarters with very well-developed muscle attachment sites, indicating a powerful forelimb and shoulder musculature. The neck was proportionally much longer than in extant felids, and the thoracic and particularly lumbar region was proportionally shorter, mimicking the condition in other derived sabrecats from which large parts of the vertebral column is known. Megantereon probably lived in open-forest environments and preyed on cervids, which were dispatched with a shearing bite from the hypertrophied and blade-like upper canines to the throat of the prey, while the prey was held immobile with the massive forelimbs, thus minimizing the risk of damage to the fangs.