Taeniolabis (Greek for "ribbon lips"); pronounced TAY-nee-oh-LAY-biss
Woodlands of North America
Paleocene (65-55 million years ago)
Size and Weight:
Up to 3 feet long and 50 pounds
Relatively large size; large, grinding teeth
The multituberculates--named after the characteristic shape of their tooth cusps, or "tubercles"--were the most successful mammals on earth during the Cretaceous period, and isolated populations managed to survive right through the Oligocene epoch. The North American Taeniolabis is the largest multituberculate yet discovered, measuring up to three feet from head to tail and weighing as much as 50 pounds, truly gigantic compared to its mostly mouse-sized relatives. This may (or may not) be explained by the fact that Taeniolabis fossils date to the Paleocene epoch, after the dinosaurs had gone extinct and mammals had some space to "stretch out" in terms of size.