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A new clade of archaic large-bodied predatory dinosaurs (Theropoda: Allosauroidea) that survived to the latest Mesozoic

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Non-avian theropod dinosaurs attained large body sizes, monopolising terrestrial apex predator niches in the Jurassic-Cretaceous. From the Middle Jurassic onwards, Allosauroidea and Megalosauroidea comprised almost all large-bodied predators for 85 million years. Despite their enormous success, however, they are usually considered absent from terminal Cretaceous ecosystems, replaced by tyrannosaurids and abelisaurids. We demonstrate that the problematic allosauroids Aerosteon, Australovenator, Fukuiraptor and Neovenator form a previously unrecognised but ecologically diverse and globally distributed clade (Neovenatoridae, new clade) with the hitherto enigmatic theropods Chilantaisaurus, Megaraptor and the Maastrichtian Orkoraptor. This refutes the notion that allosauroid extinction pre-dated the end of the Mesozoic. Neovenatoridae includes a derived group (Megaraptora, new clade) that developed long, raptorial forelimbs, cursorial hind limbs, appendicular pneumaticity and small size, features acquired convergently in bird-line theropods. Neovenatorids thus occupied a 14-fold adult size range from 175 kg (Fukuiraptor) to approximately 2,500 kg (Chilantaisaurus). Recognition of this major allosauroid radiation has implications for Gondwanan paleobiogeography: The distribution of early Cretaceous allosauroids does not strongly support the vicariant hypothesis of southern dinosaur evolution or any particular continental breakup sequence or dispersal scenario. Instead, clades were nearly cosmopolitan in their early history, and later distributions are explained by sampling failure or local extinction.
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... The latest surviving group was Carcharodontosauria, which thrived in Gondwana from the Late Jurassic to the end of the Cretaceous (e.g. [1,2]), but disappeared in Laurasia after the Turonian. Carcharodontosaurians attained extreme body sizes (greater than 6000 kg [3]), rivalling those of tyrannosaurids and spinosaurids. ...
... Carcharodontosaurians attained extreme body sizes (greater than 6000 kg [3]), rivalling those of tyrannosaurids and spinosaurids. Considered as the apex predators in Laurasia until the mid-Cretaceous [1,4], carcharodontosaurians and other large-bodied theropods (ceratosaurids and spinosaurids) disappeared after which tyrannosauroids (primarily tyrannosaurids) occupied top predatory niches during the last 20 million years of the Cretaceous (Campanian and Maastrichtian). ...
... Fukuiraptor, Shaochilong and Siamraptor) (e.g. [1,4,5,40,50]), Ulughbegsaurus uzbekistanensis gen. et sp. ...
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... Carcharodontosauria also includes megaraptorans (Benson et al., 2010), extending the biochron of this lineage until the Maastrichtian (Novas et al., 2008;Méndez et al., 2012). Finally, Patagonian coelurosaurs are generally smaller sized theropods, some of them recovered as basal forms within ...
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... The new character proposed on this study, 360(2): mid and posterior caudals, centrum, ventral surface with a thin and deep sulcus, is recovered as a synapomorphy of the Allosauroidea, corroborating the allosauroid nature of MCT 2670-LE. This character state is reversed in Shaochilong + Carcharodontosaurinae (see Coria &Currie 2006 for Mapusaurus, andBenson et al. 2010 for Shaochilong). The presence of this feature indicates that MCT 2670-LE could be a basal carcharodontosaurian, or at least an allosauroid taxon closely related to the Carcharodontosauria clade. ...
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