Dinosaurs · Small theropod

Segisaurus

Say it sayg-ee-sore-us. The name means ‘Segi [Canyon] lizard’.

Segisaurus beside a person 1.75 m tall. Ticks mark every metre.Body shape drawn for this site, showing the general build of small theropods

Length: 1.5 m
Diet: Meat-eater
When: Mid Jurassic195 to 180 million years ago
Fossils found in: USA
Named by: Camp (1936)
Family tree: Dinosauria › Saurischia › Theropoda › Neotheropoda › Coelophysoidea › Coelophysidae

Where Segisaurus sits in the age of dinosaurs.Periods from the ICS chart; dinosaur dates from the Natural History Museum

Small theropods. Small two-legged dinosaurs, many feathered, the group that includes birds. See all 60

Lived at the same time

Ammosaurus · same country
Podokesaurus · same country
Coelophysis · same country
Anchisaurus · same country
Dilophosaurus · same country
Kotasaurus
Emausaurus
Aardonyx

Other small theropods

Podokesaurus Mid Jurassic
Sarcosaurus Early Jurassic
Liliensternus Late Triassic
Gasosaurus Mid Jurassic
Proceratosaurus Mid Jurassic
Procompsognathus Late Triassic
Anchiornis Late Jurassic
Coelophysis Late Triassic

Source: Segisaurus in the Natural History Museum Dino Directory, read 12 November 2026. Sizes are the museum's estimates for a typical adult. "Lived at the same time" lists dinosaurs whose dates overlap, which does not always mean they met.