Open Paleo

Hadrosaurus

Leidy, 1858 HAD-ro-SAWR-us /ˌhædrəˈsɔːrəs/

From Greek hadros (bulky, stout) and sauros (lizard); meaning 'bulky lizard'

83.6–72.2 million years ago Campanian, Late Cretaceous
Late Cretaceous stages

Hadrosaurus is a genus of hadrosaurid ornithopod dinosaurs that lived in North America during the Late Cretaceous Period in what is now the Woodbury Formation in New Jersey about 83.6 to 77.9 million years ago. The holotype specimen was found in fluvial marine sedimentation, meaning that the corpse of the animal was transported by a river and washed out to sea. Some fossils are found in the Tar Heel/Coachman Formation.

Diagnosis

  1. Deltopectoral crest very short, only slightly over 40% of total humerus length
  2. Deltopectoral crest expanding smoothly from the humeral shaft, its laterodistal corner forming a wide, arcuate profile
  3. Ventral apex of the supraacetabular crest positioned above the posteroventral corner of the ischial peduncle of the ilium
  4. Supraacetabular crest anteroposteriorly short, its breadth about half the length of the central iliac plate

Species

Hadrosaurus foulkii Leidy, 1858

Type species

Named for William Parker Foulke, the amateur naturalist who excavated and brought the holotype specimen to the attention of paleontologist Joseph Leidy in 1858.

Holotype
ANSP 10005 , Academy of Natural Sciences of Philadelphia
Material
Fragmentary maxillae with isolated maxillary and dentary teeth; partial dorsal and caudal vertebrae; partial right coracoid; left humerus, radius, and ulna; left ilium; right ischium; partial right pubis; and a partial left hind limb (femur, tibia, fibula, metatarsals II and IV, and a pedal phalanx).
Horizon
Woodbury Formation, Campanian, Late Cretaceous , 83.6–72.2 million years ago
Locality
Hopkins farm, Haddonfield, New Jersey, United States

References

  1. Leidy, J. (1858). [On the bones of a huge herbivorous saurian near Haddonfield]. Proceedings of the Academy of Natural Sciences of Philadelphia 10: 215-218. leidy1858a
  2. Prieto-Márquez, A.; Weishampel, D. B.; Horner, J. R. (2006). The dinosaur Hadrosaurus foulkii, from the Campanian of the East Coast of North America, with a reevaluation of the genus. Acta Palaeontologica Polonica 51(1): 77-98. Polska Akademia Nauk Instytut Paleobiologii (Institute of Paleobiology, Polish Academy of Sciences).

    Detailed redescription of the holotype and reevaluation of the genus; finds Hadrosaurus not cogeneric with Gryposaurus or Kritosaurus.

    prieto-márquez2006a
  3. Prieto-Márquez, A. (2011). Revised diagnoses of Hadrosaurus foulkii Leidy, 1858 (the type genus and species of Hadrosauridae Cope, 1869) and Claosaurus agilis Marsh, 1872 (Dinosauria: Ornithopoda) from the Late Cretaceous of North America. Zootaxa 2765(1): 61-68. Magnolia Press. doi:10.11646/zootaxa.2765.1.6

    Provides a revised diagnosis treating Hadrosaurus foulkii as a valid, diagnosable taxon based on a unique combination of humeral and iliac characters.

    prieto-márquez2011b
  4. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Ornithischians. Princeton University Press.

    Source of the hip height estimate.

    jones2026a