Acrocanthosaurus atokensis, a New Genus and Species of Lower Cretaceous Theropoda from Oklahoma

Abstract

A new genus and species of aberrant Theropoda based on remains of two individuals from the Trinity sands of southeastern Oklahoma is described. All important parts of the skeletons are represented and indicate an animal of exceptional size. The genus is characterized by greatly elongated and massive neural spines in allusion to which the generic name Acrocanthosaurus is proposed. In general, the skeletal features indicate a large rather advanced carnosaur, which, however, had not yet reached the high degree of development present in the Upper Cretaceous deinodonts. The relationships to other longspined forms are discussed. Despite marked similarities to certain members of the Megalosauridae, the present genus appears most closely allied to the Allosauridae. The status of Altispinax is discussed.

Poekilopleuron bucklandii, the theropod dinosaur from the Middle Jurassic (Bathonian) of Normandy

“…A small additional spur is located anterior to the neural spines on the neural arches (Text-®g. 1A±B), but is not as well developed as in Allosaurus, Acrocanthosaurus (Stovall and Langston 1950), Lourinhanosaurus (Mateus 1998) and Siamotyrannus (Buffetaut et al 1996). The six chevrons ®gured by Eudes-Deslongchamps (1838, pl.…”

Phylogenetic definitions and nomenclature of the major taxonomic categories of the carnivorous Dinosauria (Theropoda)

“…The removal of some taxa that turned out to belong to Abelisauridae (lndosuchus and Indosaurus: Molnar, 1990;Bonaparte, 1991 ; see above) leaves Allosaurus, Acrocanthosaurus, and Dryptosaurus among Gauthier's original constitution of Carnosauria. According to some recent analyses, Dryptosaurus is more likely a coelurosaur than a carnosaur (Denton, 1990 ;Holtz, 1995; but see Carpenter et al, 1997), so Carnosauria is reduced to two genera, Allosaurus and Acrocanthosaurus, which were already regarded as closely related by Stovall and Langston (1950) . Holtz (1994) included both in the Allosauridae, distinguished by the form of the pubic foot (longer anteriorly than posteriorly, triangular in ventral view) .…”

The biogeography and ecology of the Cretaceous non-avian dinosaurs of Appalachia

“…The low genus-level similarity between the faunas is likely augmented because of the lack of specimens from the Arundel assignable to specific genera, as half the genera known from the Arundel (Deinonychus, Acrocanthosaurus, Tenontosaurus) are known from the Cloverly and Ruby Ranch faunas (Table 1 of Appendix 1). Acrocanthosaurus and Deinonychus specimens have also been collected from the Twin Mountain and Antlers formations of Texas and Oklahoma (Stovall and Langston, 1950;Cifelli, 1997;Harris, 1998;Currie and Carpenter, 2000;, and in addition to the common occurrence of Tenontosaurus remains (e.g., Ostrom, 1970;Forster, 1984;Forster, 1990;Winkler et al, 1997;Weishampel et al, 2004), the ankylopollexian iguanodontians Hippodraco and Theiophytalia are present during the Aptian in the American west (Brill and Carpenter, 2006;. The lack of reported ornithomimosaur material from the Ruby Ranch member of the Cedar Mountain Formation is not regarded as significant, as the possible ornithomimosaur Nedcolbertia justinhofmanni is known from the slightly older Yellow Cat Member of the Cedar Mountain Formation (Brownstein, 2017a;Kirkland and Hunt-Foster, 2017).…”