Tarchia

Tarchia was one of the largest and most robust ankylosaurs known from Asia, inhabiting what is now the Gobi Desert of Mongolia during the Late Cretaceous. Measuring up to six and a half metres in length and weighing over two and a half tonnes, this heavily armored animal was well adapted to arid and semi-arid conditions. Its skull was particularly broad, covered in knobby, polygonal dermal scutes, and supported an exceptionally large endocranial cavity, which inspired its name meaning brainy lizard. Tarchia was equipped with a massive tail club capable of inflicting severe blunt trauma on threatening predators like Tarbosaurus. Its complex nasal passages were likely an adaptation for moistening dry air and conserving bodily water in desert conditions.

Its name refers to its enlarged braincase, which was unusually spacious for an ankylosaur.

Where and when

Tarchia lived in the Late Cretaceous, from 75 to 70 million years ago (Campanian-Maastrichtian age). Its remains come from Mongolia, in the Barun Goyot Formation.

The numbers

Length 6 m (estimates run from 5.5 to 6.5 m). Mass about 3 t. Hip height about 1.7 m. That is 3.5 human-lengths, or 0.54 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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