Data from: New small-bodied ornithopods (Dinosauria, Neornithischia) from the Early Cretaceous Wonthaggi Formation (Strzelecki Group) of the Australian-Antarctic rift system with revision of Qantassaurus intrepidus Rich and Vickers-Rich, 1999

The Flat Rocks locality in the Wonthaggi Formation (Strzelecki Group) of the Gippsland Basin, southeastern Australia, hosts fossils of a late Barremian vertebrate fauna that inhabited the ancient extensional rift between Australia and Antarctica. Known from its dentary, Qantassaurus intrepidus has been the only dinosaur named from this formation. However, the plethora of vertebrate fossils collected from the Flat Rocks locality, suggested further dinosaurs awaited discovery. A new small-bodied ornithopod, Galleonosaurus dorisae n. gen. n. sp., is named from craniodental remains. The G. dorisae holotype is the most complete dinosaur maxilla currently known from Victoria and with four additionally referred maxillae provides an ontogenetic growth series, the first time recognised from the crania of an Australian dinosaur. Micro-CT imagery of the holotype reveals the complex internal anatomy of the neurovascular tract and antorbital fossa. Q. intrepidus is uniquely characterised by a deep foreshortened dentary. Two dentaries originally referred to Q. intrepidus are reassigned to Q. ?intrepidus and a further maxilla is referred to cf. Atlascopcosaurus loadsi. A further ornithopod dentary morphotype is identified, more elongate than those of Q. intrepidus and Q. ?intrepidus and with three more tooth positions. This dentary may pertain to G. dorisae. This work supports the presence of at least five ornithopod taxa in Victoria. The phylogenetic analysis recovered Cretaceous Victorian and Argentinian non-styracosternan ornithopods within the Gondwanan clade Elasmaria. The large-bodied taxon Muttaburrasaurus langdoni is a basal iguanodontian with closer affinities to dryomorphans than to rhabdodontids