Dinosaur footprints from the Lower Jurassic (Hettangian–Sinemurian) Precipice Sandstone of the Callide Basin, Queensland.

Dinosaur footprints from the Lower Jurassic (Hettangian–Sinemurian) Precipice Sandstone of the Callide Basin, Queensland. These are tracks on three ex-situ surfaces from Dunn Hill (Sections A and S) and Boundary Hill of the Callide mine. These pedal impressions are assignable to the ornithischian dinosaur ichnospecies Anomoepus scambus. One surface contains a single print, a second contains a trackway with two tracks, and the third has at least 69 footprints (including 13 trackways and numerous isolated prints). The latter represents one of the most densely concentrated dinosaur track surfaces in Australia (~71 tracks per square metre). Dinosaur trackmakers were estimated ranging in size from 20-76 cm at the hip, and for those with trackway, exhibit a walking gait with speeds between 2.15–5.78 km/hr. Simple invertebrate burrows (Skolithos) are abundant on the surfaces, indicating that the tracks were formed in subaqueous, moderate-to-high energy conditions. With no dinosaurian osteological record from Australia’s Early Jurassic, these footprints provide valuable evidence for the presence, abundance, and behaviour of ornithischian dinosaurs in the region.