Carnotaurus sastrei KAR-no-TOR-us

"Meat-eating bull"

Carnotaurus silhouette
You 1.8 m (5.9 ft) tall
Carnotaurus 8 m (26.2 ft) long
5 people holding hands
silhouette · thetruespinofanboi (CC0) via PhyloPic
Length
8 m (26.2 ft) — About 8 m long, ~1.6 tonnes — fast-running with tiny vestigial arms.
Period
Late Cretaceous (72–69 Mya)
Place
South America · Argentina
Food
Carnivore — Medium-sized prey, probably caught at high speed — long legs and a streamlined body.
Clade
Ceratosauria Dinosauria Saurischia Theropoda

Carnotaurus had two short bull-like horns above its eyes and arms even smaller than T. rex’s — the forearms were almost gone entirely. It was built for speed: long legs, a streamlined snout, and a tail that anchored powerful running muscles. Its skin is partly known from impressions, showing rows of bumpy scales but no feathers.

What we know

  • Two thick bony horns above the eyes — unique among theropods.
  • Arms so short they were almost vestigial — even shorter than T. rex.
  • Skin impressions show rows of small scales (no feathers preserved).
  • Long, deep skull with a short snout — a fast bite, but lower force than a T. rex.

What we guess

  • What the horns were for — display, head-butting rivals, or both.
  • Top running speed — long legs and tail muscle attachments suggest fast, but estimates vary.
  • Why the arms shrank so much — possibly because the bite and skull took over all prey-handling jobs.