Baryonyx

Baryonyx was an extraordinary fish-hunting theropod uncovered in a Surrey clay pit in 1983, revolutionising scientific views on spinosaurid ecology. Measuring up to ten metres in length, this Early Cretaceous predator possessed a long, narrow snout lined with finely serrated, conical teeth and a distinctive rosette tip reminiscent of modern crocodilians. Its name honours a massive, curved thirty-centimetre claw found on each first thumb, which it may have used to gaff slippery prey from riverbanks. Unlike its later African relative Spinosaurus, Baryonyx lacked an enormous neural sail, possessing only a modest ridge along its spine. Fossilised stomach contents directly confirmed its diet of large prehistoric fish, though it also scavenged or hunted young ornithopod dinosaurs, showcasing an opportunistic semiaquatic lifestyle in subtropical delta environments.

Its stomach cavity preserved partially digested, acid-etched scales of the large fish Lepidotes alongside bones of a juvenile Iguanodon.

Where and when

Baryonyx lived in the Early Cretaceous, from 130 to 125 million years ago (Barremian age). Its remains come from United Kingdom and Spain, in the Weald Clay Formation.

The numbers

Length 8.8 m (estimates run from 7.5 to 10 m). Mass about 1.5 t. Hip height about 2.5 m. That is 5.2 human-lengths, or 0.79 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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