Alioramus

Alioramus was a slender, long-snouted tyrannosaurid that roamed the floodplains of late Cretaceous Mongolia. Unlike heavily built relatives such as Tarbosaurus, it was lightly constructed, built for speed and agile pursuit. The skull is notably low and elongated, boasting five small bony crests along the bridge of the snout and bearing more teeth than almost any other tyrannosaurid. It grew to around five or six metres in length and weighed roughly half a tonne, making it a medium-sized predator of small vertebrates and young dinosaurs. While known specimens represent juveniles or subadults, discoveries of its close relative Qianzhousaurus confirmed that this long-snouted body plan persisted into adulthood. Its unusual head shape suggests a distinct ecological role, perhaps targeting fleet-footed prey rather than heavily armoured or bulky herbivores.

Alioramus possessed a long, slender snout decorated with a row of five distinct bony bumps or crests.

Where and when

Alioramus lived in the Late Cretaceous, from 71 to 68 million years ago (Maastrichtian age). Its remains come from Mongolia, in the Nemegt Formation.

The numbers

Length 5.5 m (estimates run from 5 to 6 m). Mass about 590 kg. Hip height about 1.7 m. That is 3.2 human-lengths, or 0.49 of a double-decker bus. These are estimates from partial skeleton; fields marked estimated by the site are length, mass, hip height.

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