Fossil range: Early Cretaceous
Replica head and forelimb of a Baryonyx walkeri skeleton
Charig & Milner, 1986
B. walkeri Charig & Milner, 1986 (type)
Suchosaurus? Owen, 1841
Baryonyx (pronounced /ˌbæriːˈɒnɪks/ meaning "heavy claw", referring to its large claw (Greek βαρως/barus meaning 'heavy' and ονυξ/onyx meaning 'claw' or 'nail'
is a genus of carnivorous dinosaur first discovered in clay pits just south of Dorking, England, and later reported from fossils found in northern Spain and Portugal. It contains one species, Baryonyx walkeri. Its fossils have been dated to the Barremian period of Early Cretaceous Period, around 125 million years ago.
Baryonyx is one of the few known piscivorous (fish-eating) dinosaurs, with specialized adaptions like a long low snout with narrow jaws filled with finely serrated teeth and gaffe hook-like claws to help it hunt its main prey.
Baryonyx was about 8.5 m (28 ft) long and weighed in the region of 1,700 kg. However, analysis of the bones suggests that the most complete specimen was not yet fully grown, so Baryonyx may have grown even larger.
Baryonyx had a large claw on the thumb of each hand, which measured at about 35 cm (14 in). Its long neck was not as strongly S-curved as in many other theropods. The skull was set at an acute angle, not the 90° angle common in similar dinosaurs. The long jaw was distinctly crocodilian, and had 96 teeth, twice as many as its relatives. Sixty-four of the teeth were placed in the lower jaw (mandible), and 32 large ones in the upper (maxilla). The snout probably bore a small crest. The upper jaw had a sharp angle near the snout, a feature seen in crocodiles that helps to prevent prey from escaping. A similar feature is also seen in shrikes.[link]