Concavenator

Concavenator was an unusual carcharodontosaurid theropod that lived in wetlands across what is now central Spain during the Early Cretaceous. Preserved as an exquisitely complete articulated skeleton, it stood roughly six metres long. Two features make Concavenator unique: two vertebrae above its hips supported a tall, pointed hump whose function remains speculative, perhaps serving for visual display or fat storage. Additionally, pits along its ulna have been interpreted as quill knobs, suggesting the presence of display structures or primitive feathers along its lower arms. If true, this represents the earliest evidence of feather-like filaments in large carnosaurian predators. Concavenator was a lithe, swift carnivore that preyed on contemporary ornithopods and juvenile sauropods.

It possessed a sharp, pointed crest on its hips and quill knobs along its forearms.

Where and when

Concavenator lived in the Early Cretaceous, from 126 to 122 million years ago (Barremian age). Its remains come from Spain, in the Calizas de La Huerguina Formation.

The numbers

Length 5.8 m (estimates run from 5.5 to 6 m). Mass about 420 kg. Hip height about 1.6 m. That is 3.4 human-lengths, or 0.52 of a double-decker bus. These are estimates from near-complete skeleton; fields marked estimated by the site are length, mass, hip height.

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