Open Paleo

Lapampasaurus

Coria et al., 2012 la-PAM-puh-SOR-us

Named after La Pampa Province of Argentina, where it was found, combined with Greek 'sauros' (lizard); meaning 'La Pampa lizard'

72.2–66.0 million years ago Maastrichtian, Late Cretaceous
Late Cretaceous stages

Lapampasaurus is an extinct genus of hadrosaurid known from the Late Cretaceous Allen Formation (late Campanian or early Maastrichtian stage) of La Pampa Province, Argentina. It contains a single species, Lapampasaurus cholinoi. The generic name refers to the Argentine province of La Pampa. The specific name honors the late collector José Cholino. The material includes cervical, dorsal, sacral and caudal vertebrae, the forelimb girdle, and the partial hindlimb.

Under dispute

Lapampasaurus cholinoi is known from very fragmentary remains, which its describers judged too incomplete for a cladistic analysis while referring it to Hadrosauridae on synapomorphies (Coria and colleagues, 2012). Alarcón-Muñoz and colleagues (2023) coded it for only 11 of 365 characters and excluded it from their results; when included it falls within Saurolophinae near Kamuysaurus.

Diagnosis

  1. Anterior cervical vertebrae with lateral foramina located on the dorsal face of diapophyses
  2. Scapula with deltoid crest of sharp lateral edge and convex dorsal surface
  3. Pedal ungual phalanx longer than wide with grooves and superficial foramina
  4. Shallow longitudinal ventral elevation on pedal ungual phalanx

Species

Lapampasaurus cholinoi Coria et al., 2012

Type species

Named for the late collector José Cholino, who contributed to the recovery of fossil material from the Allen Formation of La Pampa Province, Argentina.

Holotype
MPHN-Pv-01 , Museo Provincial de Historia Natural de La Pampa
Material
Two incomplete cervical neural arches, five cervical vertebral bodies, three incomplete dorsal neural arches, five dorsal vertebral bodies, three sacral fragments, two anterior caudal vertebral bodies, one nearly complete mid-distal caudal vertebra, incomplete left scapula, incomplete left coracoid, fragment of right prepubic process, distal third of right femur, phalanx 1 of digit III, pedal ungual phalanx.
Horizon
lower Allen Formation, Maastrichtian, Late Cretaceous , 72.2–66.0 million years ago
Locality
Islas Malvinas bentonite quarry, La Pampa, Argentina

References

  1. Coria, R. A.; González Riga, B.; Casadío, S. (2012). Un Nuevo Hadrosáurido (Dinosauria, Ornithopoda) de la Formación Allen, Provincia de la Pampa, Argentina [A New Hadrosaurid (Dinosauria, Ornithopoda) from the Allen Formation, La Pampa Province, Argentina]. Ameghiniana 49(4): 552-572. Asociacion Paleontologica Argentina. doi:10.5710/amgh.9.4.2012.487

    Named Lapampasaurus and referred it to Hadrosauridae on synapomorphies, without a cladistic analysis.

    coria2012a
  2. Alarcón-Muñoz, J.; Vargas, A. O.; Püschel, H. P.; Soto-Acuña, S.; Manríquez, L.; Leppe, M.; Kaluza, J.; Milla, V.; Gutstein, C. S.; Palma-Liberona, J.; Stinnesbeck, W.; Frey, E.; Pino, J. P.; Bajor, D.; Núñez, E.; Ortiz, H.; Rubilar-Rogers, D.; Cruzado-Caballero, P. (2023). Relict duck-billed dinosaurs survived into the last age of the dinosaurs in subantarctic Chile. Science Advances 9(24). American Association for the Advancement of Science (AAAS). doi:10.1126/sciadv.adg2456

    Hadrosaur phylogeny excluding or nesting fragmentary Lapampasaurus within the clade.

    alarcón-muñoz2023a
  3. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Ornithischians. Princeton University Press.

    Treats Lapampasaurus as a hadrosaurid of indeterminate placement.

    jones2026a