New Australovenator Hind Limb Elements Pertaining to the Holotype Reveal the Most Complete Neovenatorid Leg

Abstract

We report new skeletal elements pertaining to the same individual which represents the holotype of Australovenator wintonensis, from the ‘Matilda Site’ in the Winton Formation (Upper Cretaceous) of western Queensland. The discovery of these new elements means that the hind limb of Australovenator is now the most completely understood hind limb among Neovenatoridae. The new hind limb elements include: the left fibula; left metatarsal IV; left pedal phalanges I-2, II-1, III-4, IV-2, IV-3; and right pedal phalanges, II-2 and III-1. The detailed descriptions are supported with three dimensional figures. These coupled with the completeness of the hind limb will increase the utility of Australovenator in comparisons with less complete neovenatorid genera. These specimens and the previously described hind limb elements of Australovenator are compared with other theropods classified as neovenatorids (including Neovenator, Chilantaisaurus, Fukuiraptor, Orkoraptor and Megaraptor). Hind limb length proportion comparisons indicate that the smaller neovenatorids Australovenator and Fukuiraptor possess more elongate and gracile hind limb elements than the larger Neovenator and Chilantaisaurus. Greater stride lengths to body size exist in both Fukuiraptor and Australovenator with the femur discovered to be proportionally shorter the rest of the hind limb length. Additionally Australovenator is identified as possessing the most elongate metatarsus. The metatarsus morphology varies with body size. The larger neoventorids possess a metatarsus with greater width but shorter length compared to smaller forms.

Pedal Proportions of Poposaurus gracilis: Convergence and Divergence in the Feet of Archosaurs

“…P,R,S; also see Gilmore, ; Galton, ; Weishampel et al, ), basal ceratopsians (Fig. O) and theropods (Osborn, ; Shapiro et al, ; Longrich, ; Makovicky et al, ; Xu et al, ; Cullen et al, ; White et al, ), is the presence of distinct flanges or “wings” running longitudinally along both sides of the bottom of the ungual. Such wings become exaggerated in large ornithopods (Fig.…”

Peer Review #1 of "Late Jurassic theropod dinosaur bones from the Langenberg Quarry (Lower Saxony, Germany) provide evidence for several theropod lineages in the central European archipelago (v0.1)"

“…Suchomimus tenerensis: MNN GDF501; Torvosaurus tanneri: BYU VP 9620; Britt, 1991;Benson, 2010). In allosauroids, such as Allosaurus fragilis (Madsen, 1976), Neovenator salerii (MIWG 6348;Brusatte et al, 2008), or Australovenator wintonensis (White et al, 2013), the medial fossae are usually deeper, and proximally well bound by a sharp margin, whereas the fossa on DfMMh/FV/287 simply becomes shallower proximally.…”

New theropod remains and implications for megaraptorid diversity in the Winton Formation (lower Upper Cretaceous), Queensland, Australia

“…The medial malleolus is incomplete posteriorly and probably would have been somewhat longer still in life (based on comparisons with Australovenator (see fig. 7 in [24]). A shallow collateral ligament pit is present on the medial surface ( figure 6c,h), whereas the lateral pit is deep but missing part of the ventral rim (figure 6d,i).…”

“…These are: Rapator ornitholestoides, known only from a metacarpal I [2][3][4]; Walgettosuchus woodwardi, represented by a partial caudal vertebra [2,3]; Kakuru kujani, restricted to an incomplete tibia [3,[5][6][7]; Timimus hermani, known only from a femur [3,[8][9][10][11][12]; and Ozraptor subotaii, a distal tibia [3,6,[13][14][15][16][17][18][19][20]. The only exception is Australovenator wintonensis, represented by a partial skeleton [4,[21][22][23][24][25][26], which was initially classified as an indeterminate allosauroid but has since been universally allied with Megaraptor and its kin within Megaraptoridae [10,27,28]. Some general characteristics possessed by Megaraptoridae include: elongated three-digit hands with two enlarged recurved unguals on digits I and II and a much smaller digit III ungual [22,25,28], robust forearms [25,28], small blade-like teeth [9,23,[29][30]…”

“…The only exception is Australovenator wintonensis, represented by a partial skeleton [4,[21][22][23][24][25][26], which was initially classified as an indeterminate allosauroid but has since been universally allied with Megaraptor and its kin within Megaraptoridae [10,27,28]. Some general characteristics possessed by Megaraptoridae include: elongated three-digit hands with two enlarged recurved unguals on digits I and II and a much smaller digit III ungual [22,25,28], robust forearms [25,28], small blade-like teeth [9,23,[29][30][31][32][33]; proportionally large feet compared to hind limb length and relatively gracile hindlimbs built for running [24,26]; and heavily pneumatized bones [29]. The completeness of the Australovenator type specimen has been fundamental to our current understanding of megaraptorid anatomy and phylogenetic hypotheses, and provided robust comparative data that have permitted the assignment of numerous isolated theropod specimens from the mid-Cretaceous of New South Wales [34,35] and Victoria [1,9] to Megaraptora (or its subclade Megaraptoridae), and validated an earlier report of a Megaraptor-like theropod from Victoria, based on an ulna [36].…”