Skorpiovenator

Skorpiovenator is a genus of abelisaurid theropod dinosaur from the late Cretaceous period of Argentina.

Description
Skorpiovenator was estimated to have grown up to 6 m (19.7 ft) in length. In 2010, Gregory S. Paul gave larger estimations of 7.5 m (24.6 ft) and 1.67 tonnes (1.84 short tons). In 2016, a similar size to the original estimate at 6.2 m (20.3 ft) was estimated. It had short, stubby, near-useless arms, but strong legs with powerful thighs and sturdy shins over which its large body was balanced.

Skull
Skorpiovenator's skull was short, stout and covered in the ridges, furrows, tubercles and bumpy nodules that are scattered over the heads of most abelisaurid theropods. Its slender jaws housed rows of razor-sharp teeth. Skorpiovenator may not have had a large bite force, as has been suggested for some other abelisaurids. Skorpiovenator may have used its deep skull as a club, arching its head back and swinging it down onto its prey to drive the teeth home with enough force to do some serious damage to its prey.

Discovery and naming
The type specimen was described and named by Canale, Scanferla, Agnolin, and Novas in 2009 (though the paper was released as an advanced publication online in 2008). The name Skorpiovenator bustingorryi is derived from the Greek and Latin for "scorpion hunter," due to the abundant scorpions present at the dig site, and the specific name honors Manuel Bustingorry, who owned the farm where the specimen was found. The describers have defined a new name Brachyrostra for a clade, to which Skorpiovenatorbelonged.

The type species, Skorpiovenator bustingorryi, is known from a single, nearly complete skeleton (MMCH-PV 48K) missing only sections of the tail and the majority of the forelimbs. The specimen was recovered from the lower part of the Huincul Formation in Patagonia, dating to the late Cenomanian stage, about 95 million years ago. It would have lived alongside other carnivorous dinosaurs such as the carcharodontosaurid Mapusaurus and another abelisaurid, Ilokelesia.

Phylogeny
In 2008, Canale et al. published a phylogenetic analysis focusing on the South American carnotaurines. In their results, they found that all South American forms (including Skorpiovenator) grouped together as a sub-clade of Carnotaurinae, which they named Brachyrostra, meaning "short snouts". They defined the clade Brachyrostra as "all the abelisaurids more closely related to Carnotaurus sastrei than to Majungasaurus crenatissimus."