Berberosaurus (lat.: Berberosaurus) is a genus of theropod dinosaurs, the oldest known representative of the infraorder Ceratosaurs known to science (lat.: Ceratosauria), lived on Earth in the early Jurassic period on the territory of modern Morocco.
Only one highly fragmentary skeleton without a skull has been found so far. It was found in Morocco in the Lower Jurassic (between the Pliensbachian and Toarcian stages). This genus, which is represented by a single species of Berberosaurus liassicus, was scientifically described in 2007.
Berberosaurus is especially important from a scientific point of view, as it is one of the few dinosaurs of the late Lower Jurassic period. The remains of continental faunas of this era are very poorly preserved. In addition, being the oldest genus known to science within the infraorder Ceratosaurus, Berberosaurus closes a serious gap in the scientifically documented reporting of discovered fossil remains, because the closest representative of ceratosaurus to it in age appeared on Earth only in the Upper Jurassic period (between the Kimmeridgian and Tithonian stages).
origin of name
The dinosaur owes its Latin generic name “Berberosaurus” (“Berber Lizard”) to the Berbers, who live in western North Africa, where its fossils were found. The specific epithet “liassicus” is an adjective derived from the Latin noun “Lias”, which is an obsolete name for the Lower Jurassic period.
Location of the find and its description
The only Berberosaurus skeleton known to science, belonging to a juvenile animal, was found in the early 2000s during one of the expeditions in the Moroccan province of Karzazat (Arabian.: ورززاتإقليم; fr.: Ouarzazate) near the village of Tundut (fr.: Toundoute) in the region of the High Atlas mountain range (Arabic.: الاطلس الكبير, Atlas el-Kebir).
Fossilized dinosaur bones were collected from a 4 square meter site; and 100 meters from the place of their discovery, a holotype specimen of the early sauropod tazudasaurus (lat.: Tazoudasaurus).
The fragmentary remains of Berberosaurus include one cervical vertebra, anterior part of the sacrum, the second metacarpal bone of the left hand, the femur of the right lower limb, 2 fragments of the tibia, and the fibula of the left lower limb.
The dinosaur skeleton is kept in the city of Marrakesh in the collection of the Museum of Natural History (fr.: Muséum d’Histoire Naturelle de Marrakech).
Anatomical features
According to scientists, the body length of Berberosaurus was about 6.2 meters, that is, it reached the same size as its sister Elaphrosaurus (lat.: Elaphrosaurus). This genus can be distinguished from other ceratosaurs by its unique combination of anatomical features. For example, the neck vertebrae of Berberosaurus are characterized by a small length and the presence of air-filled cavities inside them, while the animal’s tibias have a triangular cross section (viewed from below).
Classification
In the original scientific description in 2007, Berberosaurus was classified as a primitive member of the superfamily Abelisauroids (lat.: Abelisauroidea). However, already in 2008, paleontologists Matthew Carrano.: Matthew Carrano) and Scott Sampson (Scott Sampson) in their study came to the conclusion that in reality we are talking about the basal representative of the infraorder Ceratosaurus.
But, regardless of the phylogenetic classification of this genus, it was a medium-sized predatory theropod that preyed on other dinosaurs.
The systematic location of the genus within the infraorder Ceratosaurs is controversial.
So, in 2007, a group of paleontologists led by Ronan Allen.: Ronan Allain) concluded that Berberosaurus is the most ancient of all known representatives of the superfamily Abelisauroids, which unites all derivative (evolutionarily more developed) ceratosaurs. According to this point of view, although this dinosaur was older than Xenotarsosaurus (lat.: Xenotarsosaurus), abelisaurids (Abelisauridae) and noasaurids (Noasauridae), but was evolutionarily more advanced than, for example, Spinostropheus (Spinostropheus), Elaphrosaurus and Ceratosaurus (Ceratosaurus).
Allen and colleagues classify coelophysoids (lat.: Coelophysoidea) of the Triassic period as a subgroup within the infraorder Ceratosaurs, and, based on this, the Berberosaurus should have been the most ancient not among ceratosaurs, but only among abelisauroids.
However, at present, most researchers consider coelophysoids as a superfamily of dinosaurs, not included in the infraorder Ceratosaurs.
As for the classification of abelisauroids, it is based on 3 anatomical features of the arches of their cervical vertebrae. However, in 2008, Carrano and Sampson placed the genus Berberosaurus outside the superfamily Abelisauroids in their classification. These authors note that it has a number of anatomical features that, apart from it, are known only in basal ceratosaurs, for example, the characteristic shape of the muscle attachment points on the trochanter of the femur.
The cladistic analysis carried out by Carrano and Sampson led to the preliminary conclusion that the genus Berberosaurus is more basal (primitive) than the genus Ceratosaurus.
