MEANING: Southern hunter
PERIOD: Late Cretaceous
CONTINENT: Australia
Australovenator is the most complete theropod discovered in Australia. It was a lightweight megaraptoran, at 6 m in length, weighing about 500 kg. The slender skull and relatively weak jaws, as well as its uniquely flexible grasping arms, suggest that Australovenator primarily used its arms and hands while hunting.
Australovenator is from the Cretaceous. The Cretaceous is a geological period that lasted from about 145 to 66 million years ago. It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin creta, "chalk", which is abundant in the latter half of the period.
The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct flora and fauna, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth by the end of the Cretaceous, coincident with the decline and extinction of previously widespread gymnosperm groups.
The Cretaceous (along with the Mesozoic) ended with the Cretaceous–Paleogene extinction event, a large mass extinction in which many groups, including non-avian dinosaurs, pterosaurs, and large marine reptiles, died out. The end of the Cretaceous is defined by the abrupt Cretaceous–Paleogene boundary (K–Pg boundary), a geologic signature associated with the mass extinction that lies between the Mesozoic and Cenozoic Eras.
Australovenator is a megaraptoran. Megaraptora is a family of relatively large, though slender-bodied carnivorous theropods. They are known mostly from fragmentary remains, causing confusion in their phylogenetic placement, but enough of their anatomy is known to show some unique characteristics. Megaraptorans had long, lightly built skulls with many small teeth. One of their most notable characteristics is their long arms, ending in three fingers with massive curved claws. The name "megaraptora" comes from the initial belief that these large claws were the characteristic toe claws of a sizable dromaeosaur. Larger theropods typically have proportionally small arms, and this exceptional feature suggests that megaraptorans primarily used their arms and hands while hunting.