Berberosaurus

Taxobox|
name = "Berberosaurus"
fossil_range = Early Jurassic
regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Saurischia
subordo = Theropoda
infraordo = Ceratosauria
superfamilia = Abelisauroidea
genus = "Berberosaurus"
genus_authority = Allain "et al." 2007
subdivision_ranks = Species
subdivision =
*"B. liassicus" Allain "et al.", 2007 (type)

"Berberosaurus" (meaning "Berber lizard", in reference to the Berbers of Morocco) is a genus of abelisauroid theropod dinosaur from the Pliensbachian-Toarcian-age Lower Jurassic Toundoute Continental Series found in the High Atlas of Toundoute, Ouarzazate, Morocco. The type species of the genus "Berberosaurus" is "B. liassicus", in reference to the Lias epoch. "Berberosaurus" is the oldest known and most basal abelisauroid, and is based on partial postcranial remains.

Classification

Ronan Allain and colleagues, who described "Berberosaurus", performed a phylogenetic analysis and found their new genus to be the most basal known abelisauroid, more derived than "Elaphrosaurus", "Ceratosaurus", and "Spinostropheus", but less so than "Xenotarsosaurus" and abelisaurians. "Berberosaurus" is distinguished from other theropods by anatomical details found in its vertebrae, metacarpals, and hindlimb bones. Its assignment as an abelisauroid pushes back the record of this group and shows that it had diversified by the Early Jurassic.cite journal |last=Allain |first=Ronan |coauthors=Tykoski, Ronald; Aquesbi, Najat; Jalil, Nour-Eddine; Monbaron, Michel; Russell, Dale; and Taquet, Phillipe |year=2007 |title=A basal abelisauroid from the late Early Jurassic of the High Atlas Mountains, Morocco, and the radiation of ceratosaurs |journal=Journal of Vertebrate Paleontology |volume=27 |issue=3 |pages=610–624 |doi=10.1671/0272-4634(2007)27 [610:AADTFT] 2.0.CO;2 |doilabel=10.1671/0272-4634(2007)27[610:AADTFT]2.0.CO;2 ]

Discovery and history

The remains of "Berberosaurus" were discovered during a series of expeditions to the High Atlas beginning in the early 2000s. It is based on an associated partial postcranial skeleton of a subadult individual cataloged in the Muséum d'Histoire Naturelle de Marrakech; bones from this skeleton include a neck vertebra, part of the sacrum, a metacarpal, a femur, and parts of a tibia and both fibulae. Part of another femur has been assigned to the genus as well. Its remains were found in bone beds in mudflow deposits. Later tectonic activity has affected the bones.

Paleoecology and paleobiology

"Berberosaurus", like other abelisauroids, was a bipedal carnivore.cite_book |last=Tykoski |first=Ronald B. |coauthors=and Rowe, Timothy |year=2004 |chapter=Ceratosauria |editor=Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.) |title=The Dinosauria |edition=Second Edition |publisher=University of California Press |location=Berkeley |pages=47–70 |isbn=0-520-24209-2] It was of moderate size; its estimated femur length of 50.5 centimeters (19.9 in) is comparable to femur lengths given by Gregory S. Paul for animals like "Elaphrosaurus" (52.9 cm (20.8 in))cite book |last=Paul |first=Gregory S. |authorlink=Gregory S. Paul |title=Predatory Dinosaurs of the World |year=1988 |publisher=Simon & Schuster |location=New York |isbn=0-671-61946-2 |pages=266 ] and "Dilophosaurus" (55.0 cm (21.7 in)).Paul, Gregory S. (1988). "Predatory Dinosaurs of the World". 268.] Its remains were found with those of the early sauropod "Tazoudasaurus". Also from the Early Jurassic of the High Atlas, but from another formation, are the fossils of another, smaller theropod (currently in preparation).

References