Ornithopod diversity in the Griman Creek Formation (Cenomanian), New South Wales, Australia

• Published in: PeerJ
• Main Authors: Phil R. Bell, Matthew C. Herne, Tom Brougham, Elizabeth T. Smith
• Format: Article in Journal/Newspaper
• Language: English
• Published: PeerJ Inc. 2018
• Subjects: Cretaceous; Dinosauria; Ornithischia; Ornithopoda; Griman creek formation; Australia; Medicine; R; Biology (General); QH301-705.5; Antarctic; Queensland; Antarc*
• Online Access: https://doi.org/10.7717/peerj.6008; https://doaj.org/article/3ff0412528604576b89f43f8cb7ada5d

During the Early Cretaceous, dinosaur communities of the Australian-Antarctic rift system (Eumeralla and Wonthaggi formations) cropping out in Victoria were apparently dominated by a diverse small-bodied ‘basal ornithopod’ fauna. Further north, in Queensland (Winton and Mackunda formations), poorly-represented small-bodied ornithopods coexisted with large-bodied iguanodontians. Our understanding of the ornithopod diversity from the region between the Australian-Antarctic rift and Queensland, represented by Lightning Ridge in central-northern New South Wales (Griman Creek Formation), has been superficial. Here, we re-investigate the ornithopod diversity at Lightning Ridge based on new craniodental remains. Our findings indicate a diverse ornithopod fauna consisting of two-to-three small-bodied non-iguanodontian ornithopods (including Weewarrasaurus pobeni gen. et sp. nov.), at least one indeterminate iguanodontian, and a possible ankylopollexian. These results support those of previous studies that favour a general abundance of small-bodied basal ornithopods in Early to mid-Cretaceous high-latitude localities of southeastern Australia. Although these localities are not necessarily time-equivalent, increasing evidence indicates that Lightning Ridge formed a ‘meeting point’ between the basal ornithopod-dominated localities in Victoria and the sauropod-iguanodontian faunas in Queensland to the north.