Dinosaurs A to Z
Ceratosauria

Dilophosaurus wetherilli die-LOH-foh-SOR-us

"Two-crested lizard"

Dilophosaurus silhouette
You 1.8 m (5.9 ft) tall
Dilophosaurus 7 m (23 ft) long
as long as 4 people standing fingertip to fingertip
silhouette · Marie Aimée ALLARD (CC0) via PhyloPic
Length
7 m (23 ft) — About 7 m long, ~400 kg — one of the earliest large carnivorous dinosaurs.
Period
Early Jurassic (193–183 Mya)
Place
North America · Arizona
Food
Carnivore — Smaller prey, possibly including early mammals and small dinosaurs.
Clade
Ceratosauria Dinosauria Saurischia Theropoda Horned theropods: Ceratosaurus, Carnotaurus.

An Early Jurassic predator famous for the pair of thin, arched crests on its skull.

Dilophosaurus reconstruction by Connor Ashbridge
Reconstruction · Connor Ashbridge (CC-BY)

Dilophosaurus had two thin parallel crests on top of its head — too thin to be weapons, almost certainly used for display. It lived 50 million years before Velociraptor, in the Early Jurassic when dinosaurs were just becoming the dominant large land animals. The frilled, venom-spitting version from Jurassic Park is pure fiction — the real animal was as big as a cow and had no frill.

More about Dilophosaurus

Discovery

Named by Samuel P. Welles · 1970 · the Kayenta Formation in Navajo County, northern Arizona, north of Cameron near Tuba City

Three skeletons were discovered in northern Arizona in 1940 by the Navajo man Jesse Williams, who brought members of a 1942 field party to them, and the two best preserved were collected that summer. Welles first described the most complete specimen as a species of Megalosaurus in 1954, then named the new genus Dilophosaurus in 1970 once he recognized the skull crests.

The name means "two-crested lizard," from the Greek di ("two"), lophos ("crest"), and sauros ("lizard"). The species name wetherilli honors John Wetherill, an explorer and amateur archeologist.

Samuel P. Welles. The paleontologist who named the species in 1954, coined the genus Dilophosaurus in 1970, and published a detailed osteological description of it in 1984.

Did Dilophosaurus have feathers?
A resting trace of a theropodA mostly meat-eating, bipedal dinosaur. Birds are living theropods. similar to Dilophosaurus and Liliensternus has been interpreted by some researchers as showing impressions of down-like feathers around the belly and feet. Others read these impressions as sedimentological artifacts left as the animal moved, though that reading does not rule out that the track-maker may have had feathers.
Where does Dilophosaurus sit among the theropods?
Its placement has shifted over time and is debated. Welles considered it a megalosaur in 1954, revised that in 1970, and by 1974 he and Robert A. Long treated it as a ceratosauroid. In 1984 he found it showed features of both Coelurosauria and Carnosauria, the two main theropod groups of the day, and argued that division was inaccurate.

What we know

  • Two thin, paired crests on top of the skull — display structures.
  • One of the largest predators of the Early Jurassic.
  • Slender build with long legs and a long tail.
  • No fossil evidence of a frill or venom — those are Jurassic Park inventions.

What we guess

  • Color and pattern of the crests — likely bright in life, but no preserved color data.
  • Whether it hunted alone or in groups — multiple skeletons have been found together but evidence is thin.
  • Whether the small size of the upper teeth means it specialized in fish or small prey.