Abelisaurus ‭(‬Abel’s lizard‭)

Short Info

Abelisaurus ‭(‬Abel’s lizard‭)

Phonetic : Ay-bell-ih-sore-us

Named By : Jose Bonaparte‭ & ‬Fernando Novas‭ ‬-‭ ‬1985

Diet : Carnivore

Size : 7-9 meters long

Type of Dinosaur : Large Theropod

Type Species : A.‭ ‬comahuensis‭ (‬type‭)

Found in : Argentina,‭ ‬Patagonia,‭ ‬Rio Negro Province‭ ‬-‭ ‬Anacleto Formation

When it Lived : Late Cretaceous, 74-70 million years ago

Abelisaurus (/@,belI’so:r@s(also known as “Abel’s lizard”) is one of the genus of predatory abelisaurids, a theropod dinosaur that lived in the Late Cretaceous Period (Campanian) of the region that is currently South America. The carnivore was bipedal, and was likely to have reached around 7.4 metres (24 3 inches)) of length but this isn’t certain since it’s only known from one skull fragment.

Coining the species of type, Abelisaurus comahuensis Both genus as well as species were described and named by Argentine paleontologists Jose Bonaparte and Fernando Emilio Novas in 1985. The name is generic and recognizes Roberto Abel as the discoverer of the specimen that is considered to be the type, and as the director for the province-wide Museum of Cipolletti in Argentina which is where the specimen is located. The name also combines an etymological reference to the Greek sauros (sauros) meaning “lizard”. The exact name comahuensis is a tribute to the Comahue region in Argentina in which the fossil was discovered.

The Holotype, MC 11078, was discovered in 1983 on the “Cantera de the Pala Mecanica”-site located in the Lago Pellegrini quarry, which was that were mined by Abel since the year 1975. The fossil that is the only known one of Abelisaurus is skulls that lack lower jaws. The jaws are not complete, particularly to the side that is right. The majority connected between snouts and the side of the skull have been removed. Also, it is missing the majority parts of the palate (roof in the mouth). In spite of the missing pieces it is believed to be more than 85 centimetres (33 in) long.

Abelisaurus is among the numerous dinosaurs that has recently been found within Patagonia. It was initially thought to be being from the Allen Formation however subsequent studies revealed that the remains were discovered in the more ancient Anacleto Formation (part of the Neuquen Group) of Rio Negro Province, Argentina. But locally, Abelisaurus is believed to have been found in it’s Sr. Fernandez field, located in the Coniacian Allen Formation. Evidently, further research is needed. Anacleto Anacleto is an ancient geologic formation found located in South America, dating from the beginning of the Campanian phase during the Late Cretaceous Period, between 80 to 83 millions of years ago.

Because only the skull is identified It has been difficult to establish a solid measurement of the size of Abelisaurus. It is known that abelisaurids are characterized by their small heads. In 2010 Gregory S. Paul estimated the body’s length as 10 metres (32 10 in.) with a weight of three tons (3 long tons and 3-short tons). In 2012, Thomas Holtz gave a possible length of 11 meters (36.3 feet). In 2016, the length was calculated to be 7.4 meters (24 3 inches)) in a detailed analysis of the size of the abelisaur. Other authors reported an equivalent size of 7.2 meters (23.6 feet) and 1.65 tonnes (1.82 short tons).

Abelisaurus skull
Christophe Hendrickx, CC BY-SA 3.0, via Wikimedia Commons

The length of the skull was estimated to be 85 centimetres (33+1/2 in) in 1985. The skull is fairly deep. While there aren’t any bony horns or bony crests similar to those seen in other abelisaurids such as Carnotaurus rough ridges along the snout as well as above the eyes could have been some sort of crest composed of keratin that would not have fossilized. The skull’s roof is made thicker. Additionally, there are massive the fenestrae (window-like openings) within the skull. They are present in numerous dinosaurs. They also reduce the weight of the skull. One of them is a triangular antorbital-fenestra on the snout’s lateral side. The eye socket that lies behind it is quite high. It is constrained to the center by projections of bony bone from the lacrimal bone on the front and postorbital bone to the rear. The eye was situated above the constriction. Behind the eye socket , a large triangular fenestra infratemporal is found. Its shape reflects a significant forward tilt of the back of the skull.

Its frontal snout bone of the praemaxilla, had four tiny teeth. The maxilla to its rear had at the very least seven, but it could be as many as thirteenteeth.

Source: Wikipedia