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Hesperonychus

A tiny, chicken-sized dromaeosaurid

WWD - Prehistoric Planet

Hesperonychus was a tiny, chicken-sized, dromaeosaurid dinosaur.

They call it home

Hesperonychus lived in the swamps and forests of Late Cretaceous North America.

What big teeth you have

What big teeth you have

Hesperonychus used its rows of serrated, dagger-like teeth to feed on insects.



Nose knowledge

Nose knowledge

Hesperonychus might have had an excellent sense of smell, like its close relative Velociraptor.

The most fantastic find

The most fantastic find

Elizabeth Nicholls discovered the first Hesperonychus fossil, a well-preserved pelvis from the Dinosaur Park Formation in Alberta, in 1982. Nicholls died in 2004 and the fossil remained unstudied until it was relocated in a museum drawer and described by Longrich and Currie in 2007. The bone was first thought to be from a juvenile, until it was realised the pelvis was fused and must have come from the adult of a very small dinosaur.

Hesperonychus features

Hesperonychus features Height: 0.5m (1.64ft)
Length: 0.9m (2.95ft)
Weight: 1.81kg (4lbs)
Top speed: 39.0kph (18.64mph)
Vision: Being a dromaeosaurid, it is likely that Hesperonychus had excellent eyesight, probably similar to that of modern birds.
Skin: Hesperonychus almost certainly had feathers. Those of its relative, Microraptor, were iridescent – probably for displaying to potential mates. It is possible Hesperonychus had feathers like this too.
Brain: Dromaeosaurids were among the most intelligent of dinosaurs and it is likely that Hesperonychus would have been among the most intelligent of this group.
Prey: Hesperonychus probably hunted insects, mammals, amphibians and maybe even baby dinosaurs.
Bite: Philip Currie describes Hesperonychus as 'one of those nasty little raptors, like a Velociraptor, with the same kind of claws and same kind of teeth. Only much, much smaller.'
Nest: Hesperonychus probably laid eggs in a nest, which the mother would tend, like birds do today.

Hesperonychus facts and theories

Hesperonychus facts and theories

  1. One of the closest relatives of Hesperonychus is Microraptor, the weird four-winged dromaeosaur that lived in China 125 million years ago. Maybe these animals used their four wings to glide through trees.
  2. Hesperonychus had feathers and might have used them to brood the eggs of its young in nests, just like modern-day birds.
  3. Hesperonychus extends the range of the Microraptoria from China to North America. Small dinosaurs are common to China but rare in North America. Palaeontologists believe this is because smaller dinosaurs are not fossilised as well as larger ones and might have been overlooked.
  4. Hesperonychus ran on two legs and had razor-sharp talons with an enlarged sickle-shaped claw on its second toe, just like Velociraptor.