Carnotaurus (pronounced /ˌkɑːrnoʊˈtɔːrəs/; meaning "meat-eating bull") is a genus of large theropod dinosaur that lived in South America during the Late Cretaceous period, between about 72 and 69.9 million years ago.
The only known species to date is C. sastrei , which is known from a single, well-preserved set of remains, it is one of the best-understood theropods from the Southern Hemisphere. During its time, Carnotaurus was apart of the large predatorial niche in the southern regions of Gondwana.
Carnotaurus is an abelisaurid — the carnivorous dinosaurs that succeeded the carcharodontosaurids and bossed Cretaceous South American ecosystems like tyrannosaurids did in the North — and being the first of its clan to be known from relatively complete remains it did a sterling job of showcasing their weird features.
Abelisaurids' comically stumpy arms, attached to massive shoulder blades, were nothing more than wrists with a couple of fused, clawless fingers. Though practically useless, Carnotaurus's arms exhibited an impressive range of movement, implying that they might have had a role in visual display. They also had a short and high skull, but Carnotaurus looked like it had suffered a particularly high fall from the ugly tree, hit every branch on the way down then landed face first, on an anvil. It had two huge, gnarly name-prompting horns above its eyes too. But it's not all bad news.
The eyes of Carnotaurus face fully forward which hints at binocular vision, and scientists recently realised that it had the largest "caudofemoralis" muscle of any land-dwelling animal ever, relative to body size. Supported by pairs of interlocking rib-like bones along the underside of its tail and attached by a tendon to a finger-like nub of bone (fourth trochanter) on the rear of each upper leg bone (thigh), this muscle was a power pack for explosive acceleration, but it came at a cost. Unfortunately, the tail-stiffening bone structure resulted in a loss of manoeuvrability and hampered quick, fluid turns, but for straight ahead A to B hunting there was no swifter large theropod dinosaur.
An unusually slim lower jaw compared to the extremely deep skull to which it was attached raised questions about its feeding habits that so far no-one has been able to answer. But what we can be sure of, thanks to preserved skin impressions, is that Carnotaurus bucked what had become something of a trend with recent discoveries of our filament or fluff-adorned friends by being a theropod dinosaur that definitely wasn't feathered.
The first fossils of Carnotaurus were discovered at "Estancia Pocho Sastre"  in the La Colonia Formation (initially thought to be from the older Gorro Frigio aka Cerro Barcino Formation), Chubut Province, Argentina, by José F. Bonaparte in 1984. The holotype (MACN-CH 894) is a skull and partial skeleton with some skin impressions.
In The Land Before Time
Carnotaurus makes its series debut as the male "Horned Sharptooth" in The Land Before Time XIV: Journey of the Brave as the third and final antagonist. The Horned Sharptooth briefly appears and attacks Cera, Ducky, Petrie, and Spike while they are separated from Littlefoot. He later appears searching for easy prey like earlier, and nearly discovers Grandpa Longneck, Mr. Threehorn, Wild Arms, Chomper and Ruby, before being distracted by a passing flock of Ornithomimus, which he chases away.
Accuracy-wise, the Carnotaurus's film reconstruction is heavily flawed. Its horns are bovine-like in appearance instead of being cone-shaped and slightly flattened as they should be. The body shape, while using the same style as most Sharpteeth that appear in the franchise, is much too rounded for Carnotaurus, as it was a much more able-bodied creature despite its large size. It also appears to be "shrink-wrapped" more than any other Sharpteeth that appear in the films, and its arms are rather long and have three visible digits; as opposed to being stumpy, and having its four fingers being fused.
- ↑ 1.0 1.1 Candeiro, Carlos Roberto dos Anjos; Martinelli, Agustín Guillermo. "Abelisauroidea and carchardontosauridae (theropoda, dinosauria) in the cretaceous of south america. Paleogeographical and geocronological implications". Uberlândia. Sociedade de Naturaleza. 17 (33): 5–19.
- ↑ Canale, Juan I.; Scanferla, Carlos A.; Agnolin, Federico; Novas, Fernando E. (2009). "New carnivorous dinosaur from the Late Cretaceous of NW Patagonia and the evolution of abelisaurid theropods". Naturwissenschaften. 96 (3): 409–14. Bibcode:2009NW.....96..409C. PMID 19057888. doi:10.1007/s00114-008-0487-4.
- ↑ Bonaparte, José F. (1985). "A horned Cretaceous carnosaur from Patagonia". National Geographic Research. 1 (1): 149–151.
- ↑ Chomper calls the Sharptooth a 'he'.