Sabre-toothed tiger
According to The I-Spyder Book of Earth Creatures, the sabre-toothed tiger — formally known as Smilodon fatalis — was a species of cat that died out around 9000 BC because the global climate change killed off its prey. It had two remarkably-sized upper canine teeth, measuring up to 17 cm in length. It was possessed of a stout, muscular body with a thick chest, and retractable claws. It primarily ate herbivores like bison.
The last sabre-toothed tiger from Earth was saved and kept in the Museum of the Last Ones. This specimen was cloned by Eve to distract people while the cloned dodos planted bombs. The sabre-toothed tiger was worth 500 points in the I-Spyder Book of Earth Creatures. (NSA: The Last Dodo)
When he travelled back to 100,000 BC, the Eighth Doctor saw a wounded sabre-tooth tiger. He surmised that it would not survive the injury. (EDA: The Eight Doctors)
During the Ice Age, the Eleventh Doctor and Amy Pond saved a Neanderthal from a sabre-toothed tiger. (DWA: Snow Globe)
Sabre-toothed tigers were also among the native species on Tiermann's World. (NSA: Sick Building)
K9 once encountered some sabre-toothed tigers on an unnamed planet in another dimension, partially inhabited by ex-Tellac miners. They lived alongside other Earth animals from widely varying periods of evolutionary history. On this planet, he observed one fighting a mammoth. (AK9: K9 and the Missing Planet)
