The Toolebuc Formation is a geological formation that extends from Queensland across South Australia and the Northern Territory in Australia, whose strata date back to the Albian stage of the Early Cretaceous. Dinosaurs, pterosaurs, plesiosaurs, ichthyosaurs, protostegid turtles, sharks, chimaeroids and bony fish remains are among the fossils that have been recovered from the formation.
Deposition occurred in a cool to temperate inland sea setting and the present lithology is dominantly made up of limey shales with abundant Inoceramus bivalve shells. Ichthyosaurs and protostegid turtles were the most common marine reptiles at this time in the Eromanga Sea, in contrast to older Aptian deposits such as the Bulldog Shale of South Australia, which show that plesiosaurs were previously more abundant and also more diverse. The Toolebuc Formation is one of the richest known sources of Mesozoic vertebrate fossils in Australia, with notable collecting areas situated around the towns of Richmond, Julia Creek, Hughenden and Boulia.
"QM F52641 (holotype); partial snout (lacking tip of rostrum) and mandible including dentition and associated cranial/postcranial fragments; SAM P40514 (referred specimen), partial skull with rostrum and incomplete pectoral fin"