Loncosaurus

Quality 0.50 · 0 views · Updated 2 months ago

Extinct genus of dinosaurs

title: "Loncosaurus" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["ornithopoda", "dinosaur-genera", "campanian-dinosaurs", "taxa-named-by-florentino-ameghino", "fossil-taxa-described-in-1899", "dinosaurs-of-argentina"] description: "Extinct genus of dinosaurs" topic_path: "geography/argentina" source: "https://en.wikipedia.org/wiki/Loncosaurus" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Extinct genus of dinosaurs ::

| fossil_range = Late Cretaceous, | parent_authority = Ameghino, 1899 | taxon = Loncosaurus argentinus | authority = Ameghino, 1899 | synonyms =

Loncosaurus (meaning uncertain; either Araucanian "chief" or Greek "lance" "lizard") is an extinct genus of ornithopod dinosaur from the Upper Cretaceous of Provincia de Santa Cruz, Argentina. The type (and only known) species is Loncosaurus argentinus, described by the famous Argentinian paleontologist Florentino Ameghino, but is considered a dubious name. Details on this animal are often contradictory, befitting a genus that was long confused for a theropod.

Teeth attributed to cf. "Carnosaurus" may have actually belonged to Loncosaurus.

History

The holotype femur and tooth were discovered by Carlos Ameghino, Florentino's brother, between 1887 and 1898.

Ameghino named this dinosaur in 1899 from a proximal femur (MACN-1629) and tooth found near Rio Sehuen, Santa Cruz, in the Cardiel Formation (Upper Cretaceous).

Either way, he thought the remains belonged to a "megalosaurid" dinosaur, a carnivore, which Friedrich von Huene agreed with. Upon further review, von Zittel assigned it to the Coeluridae, recognized today as a "wastebasket taxon" for small carnivorous dinosaurs. The carnivore tooth helped this misidentification take hold.

It was ignored for decades until Ralph Molnar reassessed it. He found that the tooth did not belong to the same animal as the femur and removed it from the type, and suggested that the femur belonged to a hypsilophodont or turtle. Professional opinion has not changed much since then, although based on size, it appears more likely to be an iguanodont than a hypsilophodont. a view which has not been followed since.

Paleobiology

Coria estimates the size of the Loncosaurus type individual at about 5 m (16.4 feet) long. As a small to medium-sized ornithopod, it would have been an agile bipedal herbivore.

References

References

  1. [http://www.dinosauria.com/dml/names/dinol.htm Dinosaur Translation Guide L] {{webarchive. link. (2006-03-15)
  2. Olshevsky, DML 1999. http://dml.cmnh.org/1999Nov/msg00507.html
  3. Ameghino, F. 1898. Sinopsis geológico-paleontológica. ''Segundo censo de la República Argentina''. Folia:Buenos Aires, 1:112-255. [Spanish]
  4. Norman, D.B., and Weishampel, D.B. 1990. Iguanodontidae and related ornithopods. In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). ''The Dinosauria''. University of California Press:Berkeley, 510-533. {{ISBN. 0-520-06727-4
  5. Norman, D.B. 2004. Basal Iguanodontia. In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). ''The Dinosauria'' (second edition). University of California Press:Berkeley, 413-437. {{ISBN. 0-520-24209-2
  6. George Olshevsky's [http://www.polychora.com/dinolist.html Dinosaur Genera List]
  7. [[Ameghino, F.]] 1899. Nota preliminar sobre el ''Loncosaurus argentinus'', un representante de la familia Megalosauridae de la República Argentina. ''Anales de la Sociedad Cientifica Argentina'' 49:61-62. [Spanish]
  8. Coria, R.A., and Salgado, L. 1996. ''Loncosaurus argentinus'' [[Florentino Ameghino. Ameghino]], 1899 (Ornithischia, Ornithopoda): a revised description with comments on its phylogenetic relationships. ''[[Ameghiniana]]'' 33(4):373-376.
  9. Glut, D.F. (1997). ''Dinosaurs: The Encyclopedia''. Mcfarland & Company, Inc., xi-1076. {{ISBN. 0-89950-917-7
  10. Coria, R.A. 1999. Ornithopod dinosaurs from the Neuquén Group, Patagonia, Argentina: phylogeny and biostratigraphy. In Tomida, Y., Rich, T.H., and Vickers-Rich, P. (eds.) ''Proceedings of the Second Gondwanan Dinosaur Symposium, National Science Museum Monographs'' 15:47-60.
  11. [https://paleodb.org/cgi-bin/bridge.pl?user=Guest&action=displayHomePage The Paleobiology Database])
  12. von Huene, F. 1909. Skizze zu einer Systematik und Stammesgeschichte der Dinosaurier. ''Centralblatt für Mineralogie, Geologie und Paläontologie'' 1909:12-22. [German]
  13. von Zittel, K.A.. 1911. ''Grundzüge der Paläontologie (Paläozoologie).'' II. Abteilung. Vertebrata. Druck und Verlag von R. Oldenbourg:München, 1-598. [German]
  14. Molnar, R.E. 1980. Australian late Mesozoic continental tetrapods: some implications. ''Mémoires de la Société Géologique de France, Nouvelle Série'' 139:131-143.
  15. 0-679-41770-2

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::

ornithopodadinosaur-generacampanian-dinosaurstaxa-named-by-florentino-ameghinofossil-taxa-described-in-1899dinosaurs-of-argentina