Open Paleo

Muttaburrasaurus

Bartholomai & Molnar, 1981 muht-a-BUHR-a-SAWR-us

Named for Muttaburra, a town in Queensland, Australia near where the fossil was discovered, combined with Greek '-saurus' meaning 'lizard'.

113.2–93.9 million years ago Albian–Cenomanian, Early Cretaceous–Late Cretaceous
Early Cretaceous and Late Cretaceous stages

Muttaburrasaurus was a genus of herbivorous ornithopod dinosaur that lived in what is now north-eastern Australia during the Cenomanian stage of the Late Cretaceous period, about 96 million years ago. It has been recovered in some analyses as a member of the iguanodontian clade Rhabdodontomorpha, or alternately as a member of Elasmaria. After Kunbarrasaurus, it is Australia's most completely known dinosaur from skeletal remains. It was named after Muttaburra, the site in Queensland, Australia, where it was found. The dinosaur was selected from twelve candidates to become the official fossil emblem of the State of Queensland.

Under dispute

Muttaburrasaurus langdoni was long recovered within Rhabdodontomorpha (Dieudonné and colleagues, 2016; Madzia and colleagues, 2021), but Fonseca and colleagues (2024) recovered it within Elasmaria, interpreting its rhabdodontomorph resemblances as convergence, and Czepiński and Madzia (2025) likewise placed it outside Rhabdodontomorpha. Its redescription by Herne and colleagues (2026) found it craniodentally distant from rhabdodontomorphs but undertook no phylogenetic analysis, leaving its relationships unresolved.

Diagnosis

  1. Posterodorsal and posteroventral processes of the premaxilla abutting along a tight lateral suture to form the anterolateral part of the enlarged cavum nasi proprium within the dorsally inflated muzzle.
  2. Novel paired ossifications (prenasals) — either premaxillary processes or neomorphic bones — forming the dorsal roof and internal septa of the enlarged cavum nasi proprium.
  3. Horizontal septum of the prenasal dividing the cavum nasi proprium into inferior and superior airways, with a sagittal septum further dividing the superior airway into left and right meatuses.
  4. Thickened pendulous support ridge of the prenasal projecting ventrally into the superior airway meatus.
  5. Toroidal fossa at the anterior end of the nasal body forming the posterior end of the superior airway meatus.
  6. T-shaped lacrimal with a descending process projecting ventrally toward the dorsal opening of the maxillary neurovascular tract.
  7. Pterygoid lacking palatine and vomeral contacts on the anterior face of the boss for the basipterygoid process.
  8. Two protuberances at the dorsal tip of the ascending process of the supraoccipital, accommodated ventrally on the parietals.
  9. Nasal excluded from the naris by the premaxilla (convergent with Lambeosaurinae).
  10. Dentulous premaxilla bearing five alveoli, as in early-diverging neornithischians.
  11. Caniniform premaxillary teeth lacking a substantial root-crown constriction, as in some heterodontosaurids.

Species

Muttaburrasaurus langdoni Bartholomai & Molnar, 1981

Type species

Named for Doug Langdon, the grazier who discovered the holotype specimen at Rosebery Downs Station near Muttaburra, Queensland, in 1963.

Holotype
QM F6140 , Queensland Museum, Geoscience Collection
Material
Almost complete skull — including newly identified premaxillary rami bearing five premaxillary teeth — and a partial postcranium; among the most complete ornithopod specimens from Gondwana.
Horizon
lower Mackunda Formation, Albian–Cenomanian, Early Cretaceous–Late Cretaceous , 113.2–93.9 million years ago
Locality
Rock Hole, Rosebery Downs Station, Queensland, Australia Herne and colleagues (2026) infer the lower half from a 1970 Bureau of Mineral Resources map section rather than from a measured section at the locality.

Notable specimens

  • Dunluce Skull

    QM F14921 Queensland Museum, Geoscience Collection Found 1987 by John Stewart-Moore and Robert Walker complementary

    A referred skull from somewhat older Allaru Mudstone (Albian) layers than the holotype, considered by Molnar to represent a separate, yet unnamed Muttaburrasaurus species.

    Molnar (1996)

References

  1. Bartholomai, A.; Molnar, R. E. (1981). Muttaburrasaurus, a new iguanodontid (Ornithischia: Ornithopoda) dinosaur from the Lower Cretaceous of Queensland. Memoirs of the Queensland Museum 20(2): 319-349. bartholomai1981a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Ornithischians. Princeton University Press.

    Illustrated by E. Viola.

    jones2026a
  3. Molnar, R. E. (1996). Observations on the Australian ornithopod dinosaur, Muttaburrasaurus. Memoirs of the Queensland Museum 39(3): 639-652.

    Source of the hip height estimate, and the appearance features.

    molnar1996a
  4. Herne, M. C.; Bevitt, J. J.; Milan, L.; Hocknull, S. A.; Tait, A. M.; Allen, C. M.; Rozefelds, A. C.; Molnar, R. E.; Weisbecker, V.; Bell, P. R. (2026). Cranial anatomy, palaeoneurology, palaeobiology and stratigraphic age of the large-bodied ornithopod, Muttaburrasaurus langdoni Bartholomai and Molnar, 1981, from the mid-Cretaceous of Australia. PeerJ 14: e20794. PeerJ. doi:10.7717/peerj.20794

    CT-based redescription of the holotype cranium and paleoneurology; identifies premaxillary teeth and prenasal ossifications and dates the holotype locality to the Cenomanian (~96.3 Ma).

    herne2026a
  5. Dieudonné, P. E.; Tortosa, T.; Torcida Fernández-Baldor, F.; Canudo, J. I.; Díaz-Martínez, I. (2016). An unexpected early rhabdodontid from Europe (Lower Cretaceous of Salas de los Infantes, Burgos Province, Spain) and a re-examination of basal iguanodontian relationships. PLOS ONE 11: e0156251. doi:10.1371/journal.pone.0156251

    Recovered Muttaburrasaurus within Rhabdodontomorpha in their phylogenetic analysis.

    dieudonné2016a
  6. Madzia, D.; Arbour, V. M.; Boyd, C. A.; Farke, A. A.; Cruzado-Caballero, P.; Evans, D. C. (2021). The phylogenetic nomenclature of ornithischian dinosaurs. PeerJ 9: e12362. doi:10.7717/peerj.12362

    Placed Muttaburrasaurus within Rhabdodontomorpha under their revised ornithischian nomenclature.

    madzia2021a
  7. Fonseca, A. O.; Reid, I. J.; Venner, A.; Duncan, R. J.; Garcia, M. S.; Müller, R. T. (2024). A comprehensive phylogenetic analysis on early ornithischian evolution. Journal of Systematic Palaeontology 22: 2346577. doi:10.1080/14772019.2024.2346577

    Recovered Muttaburrasaurus within Elasmaria, interpreting its similarities to rhabdodontomorphs as convergence.

    fonseca2024a
  8. Czepiński, Ł.; Madzia, D. (2025). Exploring the diversity and disparity of rhabdodontomorph ornithopods from the Late Cretaceous European archipelago. Scientific Reports 15(1). Springer Science and Business Media LLC. doi:10.1038/s41598-025-98083-z

    Recovered Muttaburrasaurus outside Rhabdodontomorpha, consistent with Fonseca and colleagues (2024).

    czepiński2025a