<Li> Ischyrosmilus gracilis Churcher, 1984 </Li> <Li> Smilodontopsis gracilis Berta, 1995 </Li> <P> Smilodon is an extinct genus of machairodont felid . It is one of the most famous prehistoric mammals, and the best known saber - toothed cat . Although commonly known as the saber - toothed tiger, it was not closely related to the tiger or other modern cats . Smilodon lived in the Americas during the Pleistocene epoch (2.5 mya--10,000 years ago). The genus was named in 1842, based on fossils from Brazil . Three species are recognized today: S. gracilis, S. fatalis, and S. populator . The two latter species were probably descended from S. gracilis, which itself probably evolved from Megantereon . The largest collection of Smilodon fossils has been obtained from the Rancho La Brea Tar Pits in Los Angeles, California . </P> <P> Overall, Smilodon was more robustly built than any extant cat, with particularly well - developed forelimbs and exceptionally long upper canine teeth . Its jaw had a bigger gape than that of modern cats, and its upper canines were slender and fragile, being adapted for precision killing . S. gracilis was the smallest species at 55 to 100 kg (120 to 220 lb) in weight . S. fatalis had a weight of 160 to 280 kg (350 to 620 lb) and height of 100 cm (39 in). Both of these species are mainly known from North America, but remains from South America have also been attributed to them . S. populator from South America was the largest species, at 220 to 400 kg (490 to 880 lb) in weight and 120 cm (47 in) in height, and was among the largest known felids . The coat pattern of Smilodon is unknown, but it has been artistically restored with plain or spotted patterns . </P>

When did the saber tooth tiger go extinct