Suchomimus

Abstract: Spinosaurids are among the most distinctive and yet poorly-known of large-bodied theropod dinosaurs, a situation exacerbated by their mostly fragmentary fossil record and competing views regarding their palaeobiology. Here, we report two new Early Cretaceous spinosaurid specimens from the Wessex Formation (Barremian) of the Isle of Wight. Large-scale phylogenetic analyses using parsimony and Bayesian techniques recover the pair in a new clade within Baryonychinae that also includes the hypodigm of the African spinosaurid Suchomimus. Both specimens represent distinct and novel taxa, herein named Ceratosuchops inferodios gen. et sp. nov. and Riparovenator milnerae gen. et sp. nov. A palaeogeographic reconstruction suggests a European origin for Spinosauridae, with at least two dispersal events into Africa. These new finds provide welcome information on poorly sampled areas of spinosaurid anatomy, suggest that sympatry was present and potentially common in baryonychines and spinosaurids as a whole, and contribute to updated palaeobiogeographic reconstructions for the clade.

Abstract: Spinosaur remains were collected in Africa, Europa, Asia and Brazil, coming from deposits with ages ranging from the Late Jurassic to the Late Cretaceous. Although having a wide distribution - both geographically and temporally - little is actually known about the group since most specimens are incomplete. Up to now, only eight species were described. Spinosauridae is divided into the Baryonychinae (Suchomimus + Baryonyx + Cristatosaurus) and Spinosaurinae (Spinosaurus+ Angaturama + Irritator). Only in Africa members of both clades were found. One possible scenario that could explain the spinosaurid distribution, suggests that forms related to Baryonyx (the most primitive member of this clade) dispersed from Europe to Northern Africa, where Spinosaurinae were originated. Later, members of the Spinosaurinae further spread to South America.

Abstract: Ossified clavicles, either as paired elements or as a median furcula, have been recorded in all major clades of dinosaurs, including ornithischians, sauropodomorphs, and theropods (Bryant and Russell, 1993). Nearly all but the most basal theropods, Eoraptor lunensis and Herrerasaurus ischigualastensis , have an ossified furcula including coelophysids (Downs, 2000; Tykoski et al., 2002; Carrano et al., 2005), allosauroids (Chure and Madsen, 1996), tyrannosaurids (Makovicky and Currie, 1998; Larson and Donnan, 2002; Brochu, 2003; Lipkin and Sereno, 2004; Larson and Rigby, 2005), therizinosaurids (Xu et al., 1999a; Zhang et al., 2001), oviraptorids (Barsbold, 1983; Clark et al., 1999, 2001; Hwang et al., 2002; Osmolska et al., 2004), troodontids (Xu and Norell, 2004), and dromaeosaurids (Norell et al., 1997; Norell and Makovicky, 1999; Xu et al., 1999b; Burnham et al., 2000; Hwang et al., 2002). No ossification of any element beyond the coracoid has been found in the pectoral girdle of the well-preserved primitive theropods, Eoraptor lunensis and Herrerasaurus ischigualastensis . Although the furcula in tyrannosaurids has been described in several genera (Makovicky and Currie, 1998), the bone has never been found in articulation in any species, and controversy has surrounded the form of the furcula in Tyrannosaurus rex (Larson and Donnan, 2002; Brochu, 2003). We describe the furcula in the spinosaurid, Suchomimus tenerensis , which aids in establishing the basal condition of this bone for tetanuran theropods. We then describe furculae in Tyrannosaurus rex , one of which is preserved in articulation and others of which highlight important variation. The specimens in this study are housed in the Children's Museum of Indianapolis (CMI), Field Museum (FMNH), Musee National du Niger (MNN), Museum of the Rockies (MOR), and the University of Chicago Research Collection …