Genusaurus is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 from the Early Cretaceous

Early Cretaceous

The Early Cretaceous or the Lower Cretaceous , is the earlier or lower of the two major divisions of the Cretaceous...

. Its fossils were found in France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

. Scientists have estimated the length of Genusaurus to have been 3 m (9.8 ft) and its weight 50 kg (110 lb). Genusaurus is believed to have lived during the Albian

Albian

The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...

 faunal stage

Faunal stage

In chronostratigraphy, a stage is a succession of rock strata laid down in a single age on the geologic timescale, which usually represents millions of years of deposition. A given stage of rock and the corresponding age of time will by convention have the same name, and the same boundaries.Rock...

, around 112-100 million years ago.

Species and classification

The type species

Type species

In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

, Genusaurus sisteronis, is the only known species. It is based on a partial skeleton

Skeleton

The skeleton is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.In a figurative sense, skeleton can...

 found in 1984-1986 and described by Accarie, Beaudoin, Dejax, Fries, Michard, and Taquet in 1995. The genus name is derived from the Latin word genu (knee) and refers to a crest in front of the proximal end of the tibia

Tibia

The tibia , shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates , and connects the knee with the ankle bones....

. The species name refers to Sisteron

Sisteron

Sisteron is a commune in the Alpes-de-Haute-Provence department in the Provence-Alpes-Côte d'Azur region in southeastern France.Sisteron is situated on the banks of the River Durance just after the confluence of the rivers Buëch and Sasse...

, the town near which the specimen was found.

Accarie et al. assigned Genusaurus to the ceratosaur group of theropods. A 2008 cladistic

Cladistics

Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

 analysis by Carrano and Sampson

Scott D. Sampson

Scott D. Sampson is a paleontologist and chief curator of the Utah Museum of Natural History. Sampson is notable for his work on the carnivorous theropod dinosaurs Majungasaurus and Masiakasaurus and his extensive research into the Late Cretaceous Period, particularly in...

 placed Genusaurus in the Noasauridae

Noasauridae

Noasaurids were a group of theropod dinosaurs from the Cretaceous Period . They were generally small in size...

 along with Laevisuchus

Laevisuchus

Laevisuchus is a genus of abelisauroid theropod dinosaur from the Late Cretaceous.Its remains were discovered by Charles Alfred Matley near Jabalpur in Maastrichtian deposits in the Lameta Formation in India, and named and described by paleontologists Friedrich von Huene and Matley in 1933. The...

, Masiakasaurus

Masiakasaurus

Masiakasaurus was a small predatory theropod dinosaur from the Late Cretaceous of Madagascar. It was named in 2001 by Scott D. Sampson, Matthew Carrano, and Catherine A. Forster. Unlike most theropods, the front teeth of Masiakasaurus projected forward instead of straight down...

, Noasaurus

Noasaurus

Noasaurus is the name given to a carnivorous dinosaur genus of the late Campanian-Maastrichtian...

, and Velocisaurus

Velocisaurus

Velocisaurus is a genus of ceratosaurian theropod dinosaur from the Cretaceous period of Argentina.In 1985 Oscar de Ferrariis and Zulma Gasparini uncovered fossils at Boca del Sapo in Neuquén province of Patagonia from layers of the Bajo de la Carpa Formation, dating from the Santonian. Among them...

; in turn, noasaurids are part of the abelisaur

Abelisaur

Abelisaurs were a group of ceratosaurian dinosaurs which lived in the Southern hemisphere during the Cretaceous period. Some well-known dinosaurs of this group include Abelisaurus, Carnotaurus, and Majungasaurus. They are known for their small arms...

 group, which is part of the ceratosaur group.

External links

• Ceratosauria
• Genusaurus in the Dinosaur Encyclopedia
• "Our Exhibitions: Genusaurus sisteronis" (in French) at the Réserve Naturelle Géologique de Haute-Provence
  Provence
  Provence ; Provençal: Provença in classical norm or Prouvènço in Mistralian norm) is a region of south eastern France on the Mediterranean adjacent to Italy. It is part of the administrative région of Provence-Alpes-Côte d'Azur...
  
  , France.