Abelisaurus
Carnivore·Late Cretaceous·South America·Bipedal
Abelisaurus was a genus of predatory theropod dinosaur that lived in South America during the Late Cretaceous Period. Known primarily from a partial skull, it is estimated to have been a bipedal carnivore reaching around 7.4 meters in length.
Key Facts
- ›Abelisaurus lived during the Late Cretaceous Period (Campanian) in South America.
- ›It was a bipedal carnivore.
- ›The genus and species were named and described in 1985 by José Bonaparte and Fernando Emilio Novas.
- ›The only known fossil is a partial skull, making size estimates uncertain.
- ›It is considered one of the earliest named abelisaurids.
- Bipedal carnivore
- Skull estimated to be over 85 cm long
- Relatively deep skull with a thickened skull roof
- Large fenestrae in the skull, including a large triangular antorbital fenestra
- Premaxilla bore four small teeth, maxilla had seven to thirteen larger teeth
Aucasaurus Garridoi, Carnotaurus, Majungasaurus
Argentina
About Abelisaurus
Abelisaurus is a genus of predatory theropod dinosaur that roamed South America during the Late Cretaceous Period. Known primarily from a single partial skull discovered in Argentina, this dinosaur is classified within the Abelisauridae family, a group of theropods that were common in the Southern Hemisphere.
Discovery and Naming
The type species, Abelisaurus comahuensis, was formally named and described in 1985 by Argentine paleontologists José Bonaparte and Fernando Emilio Novas. The genus name, Abelisaurus, honors Roberto Abel, the discoverer of the fossil specimen and former director of the provincial Museum of Cipolletti, where the fossil is housed. The name also incorporates the Greek word "sauros," meaning "lizard." The species name, comahuensis, refers to the Comahue region of Argentina, the area where the fossil was found. The holotype specimen, MC 11098, consists of an incomplete skull lacking lower jaws, with significant portions missing, particularly on the right side and the palate.
Geological Context
Initially described as coming from the Allen Formation, subsequent research indicated that the remains of Abelisaurus were actually found in the older Anacleto Formation, which is part of the Neuquén Group in Río Negro Province, Argentina. The Anacleto Formation dates to the early Campanian stage of the Late Cretaceous, between approximately 83 and 80 million years ago.
Physical Characteristics and Paleobiology
Due to the fragmentary nature of the fossil, reliable size estimates for Abelisaurus are challenging. However, it is known to have been a bipedal carnivore. Estimates for its body length vary, with some suggesting around 7.4 meters (24 ft 3 in), while others propose lengths up to 10 or 11 meters. Abelisaurid skulls, in general, are noted for being relatively short. While Abelisaurus lacks the bony crests or horns seen in some related species like Carnotaurus, it may have had keratinous crests on its snout and above its eyes, which would not have fossilized. The skull features large openings (fenestrae) that reduce weight, including a prominent antorbital fenestra. The teeth suggest a diet of flesh, and it is theorized that Abelisaurus may have preyed upon large titanosaurian sauropods.
Classification
When first described, Abelisaurus was placed in the newly created family Abelisauridae and initially considered a member of Carnosauria. As more abelisaurid fossils were discovered, including more complete specimens of genera like Aucasaurus, Carnotaurus, and Majungasaurus, the classification evolved. Abelisaurids are now placed within the Neoceratosauria. Some scientists consider Abelisaurus a basal abelisaurid, while its exact phylogenetic position remains a subject of discussion. There has been speculation that future discoveries might reveal Abelisaurus to be a carcharodontosaurid, though this is generally considered unlikely.
Source: Wikipedia ↗
Frequently Asked Questions
What does the name Abelisaurus mean?
The name Abelisaurus means "Abel's lizard." The generic name honors Roberto Abel, the discoverer of the type specimen, and includes the Greek word 'sauros' meaning 'lizard.' The specific name, comahuensis, honors the Comahue region of Argentina where the fossil was found.
When did Abelisaurus live?
Abelisaurus lived during the Late Cretaceous Period, specifically the Campanian stage, between approximately 83 and 80 million years ago.
Where were Abelisaurus fossils found?
Fossils of Abelisaurus were discovered in Patagonia, South America, specifically in Río Negro Province, Argentina. The Anacleto Formation is identified as the geological source of the remains.
What did Abelisaurus eat?
As a predatory theropod, Abelisaurus was a carnivore. It is hypothesized to have hunted titanosaurian sauropods.
How large was Abelisaurus?
Estimates for Abelisaurus vary due to the incomplete fossil record. One estimate places its body length at 7.4 meters (24 ft 3 in), while others suggest lengths up to 10 or 11 meters.
Related Dinosaur species
Acheroraptor
Acheroraptor is an extinct genus of dromaeosaurid theropod dinosaur that lived in North America during the Late Cretaceous period. It is known from fossil remains discovered in the Hell Creek Formation of Montana, United States. Acheroraptor is notable for being one of the geologically youngest dromaeosaurids, existing just before the Cretaceous-Paleogene extinction event.
Achillobator
Achillobator was a large, heavily-built dromaeosaurid theropod dinosaur that inhabited Mongolia during the Late Cretaceous period. It is distinguished by its robust skeleton, deep maxilla, and primitive pelvis, contrasting with the generally lighter build of other dromaeosaurids. This predator likely hunted large prey using its enlarged sickle claw.
Adasaurus
Adasaurus is a genus of dromaeosaurid dinosaur that lived in Asia during the Late Cretaceous period. This large predator is known from two partial specimens discovered in Mongolia's Nemegt Formation. Adasaurus is distinguished by a notably reduced sickle claw on its second toe, a feature that sets it apart from many of its relatives.