Open Paleo

Atlascopcosaurus

Rich & Vickers-Rich, 1989 AT-las-KOP-ko-SAWR-us /ˌætləsˌkɒpkəˈsɔːrəs/ Disputed

Named for Atlas Copco, the company whose equipment sponsored the Dinosaur Cove excavation in Australia, combined with Greek 'sauros' meaning 'lizard'.

125.8–100.5 million years ago Barremian–Albian, Early Cretaceous
Early Cretaceous stages

Atlascopcosaurus is a genus of herbivorous ornithopod dinosaur from the Early Cretaceous Eumeralla Formation of Australia.

Under dispute

Atlascopcosaurus loadsi is based on limited material; it is recovered in Elasmaria by recent analyses but treated as a nomen dubium by some and placed in an unnamed basal-iguanodontian clade by Boyd (2015).

Diagnosis

  1. Upper cheek teeth with the crown apex set close to the posterior margin rather than midway along the tooth
  2. Upper cheek teeth bearing at least eight ridges, divided into a prominent primary ridge and markedly weaker secondary ridges rather than a gradation
  3. Primary ridge of the upper cheek teeth positioned near the posterior margin of the buccal surface
  4. Anteriormost secondary ridge projecting noticeably farther from the tooth surface than the other secondary ridges
  5. Ridges confined to the principal surface (buccal in uppers, lingual in lowers), extending nearly to the base of the crown and absent or faint on the opposite face of unworn teeth
  6. Lower cheek teeth with a relatively weak primary ridge

Species

Atlascopcosaurus loadsi Rich & Vickers-Rich, 1989 Disputed

Type species

Named for William Loads, the state manager for Atlas Copco at the time of the excavations, who assisted during the dig that discovered the dinosaur.

Holotype
NMV P166409 , Museums Victoria
Material
A left maxilla fragment with one erupted cheek tooth and three unerupted cheek teeth.
Horizon
Eumeralla Formation, Barremian–Albian, Early Cretaceous , 125.8–100.5 million years ago
Locality
Point Lewis, Victoria, Australia

References

  1. Rich, T. H.; Vickers-Rich, P. (1989). Polar dinosaurs and biotas of the Early Cretaceous of southeastern Australia. National Geographic Research 5(1): 15-53. rich1989a
  2. Boyd, C. A. (2015). The systematic relationships and biogeographic history of ornithischian dinosaurs. PeerJ 3: e1523. PeerJ. doi:10.7717/peerj.1523

    Ornithischian analysis bearing on the placement of Atlascopcosaurus.

    boyd2015a
  3. Agnolín, F. L.; Ezcurra, M. D.; Pais, D. F.; Salisbury, S. W. (2010). A reappraisal of the Cretaceous non-avian dinosaur faunas from Australia and New Zealand: evidence for their Gondwanan affinities. Journal of Systematic Palaeontology 8(2): 257-300. Informa UK Limited. doi:10.1080/14772011003594870

    Lists Atlascopcosaurus loadsi as a non-dryomorph ornithopod nomen dubium.

    agnolín2010a