Loncosaurus
Meaning uncertain; either from Araucanian 'lonco' meaning 'chief' or Greek 'lonche' meaning 'lance', combined with Greek 'sauros' meaning 'lizard'.
Loncosaurus 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.
Under dispute
Loncosaurus argentinus is based on a partial femur, long confused with theropods; it is now regarded as an indeterminate iguanodontian and a nomen dubium (Norman, 2004).
Species
Loncosaurus argentinus Ameghino, 1899 Nomen dubium
Type species
No etymology was given by Ameghino (1899). Likely from Latin 'argentinus' meaning 'Argentine', a reference to the country of origin.
- Holotype
- MACN-1629 , Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’
- Material
- Femur
- Horizon
- Mata Amarilla Formation, Cenomanian–Coniacian, Late Cretaceous , 100.5–85.7 million years ago
- Locality
- Cerro Pari Aike, Santa Cruz, Argentina
References
-
Ameghino, F. (1899). Nota preliminar sobre el Loncasaurus argentinus un representante de la familia de los Megalosauridae en la República Argentina [Preliminary note on Loncasaurus argentinus, a representative of the family Megalosauridae in the Argentine Republic]. Anales de la Sociedad Científica Argentina 47: 61-62.
Records the type material as found by Carlos Ameghino in the Guarani formation of the Río Sehuen, in a red sandstone resting on a bed of Ostrea guaranitica, without a closer locality.
ameghino1899a -
Varela, A. N.; Poiré, D. G.; Martin, T.; Gerdes, A.; Goin, F. J.; Gelfo, J. N.; Hoffmann, S. (2012). U-Pb zircon constraints on the age of the Cretaceous Mata Amarilla Formation, Southern Patagonia, Argentina: its relationship with the evolution of the Austral Basin. Andean Geology 39(3). Pontificia Universidad Católica de Valparaíso. doi:10.5027/andgeoV39n3-a01
Ties the type locality at Cerro Pari Aike to the Mata Amarilla Formation, which neither Ameghino nor Huene names.
varela2012a -
Norman, D. B. (2004). Basal Iguanodontia. The Dinosauria, Second Edition (Weishampel, D. B.; Dodson, P.; Osmólska, H., eds.) 413-437. University of California Press, Berkeley.
Regarded Loncosaurus as an indeterminate iguanodontian and a nomen dubium.
norman2004a