Huincul Formation

Not to be confused with Huincul Fault.

Huincul Formation
Stratigraphic range: Late Cenomanian-Early Turonian ~97–93 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Unit of	Neuquén Group  Río Limay Subgroup
Underlies	Lisandro Formation
Overlies	Candeleros Formation
Thickness	250 m (820 ft)
Lithology
Primary	Sandstone
Other	Claystone
Location
Coordinates	39°24′S 69°00′W / 39.4°S 69.0°W / -39.4; -69.0
Approximate paleocoordinates	46°06′S 46°00′W / 46.1°S 46.0°W / -46.1; -46.0
Region	Mendoza, Río Negro & Neuquén Provinces
Country	Argentina
Extent	Neuquén Basin
Type section
Named for	Plaza Huincul
Named by	Keidel
Year defined	1929
Huincul Formation (Argentina)

The Huincul Formation is a geologic formation of Late Cretaceous (Cenomanian to Early Turonian) age of the Neuquén Basin that outcrops in the Mendoza, Río Negro and Neuquén Provinces of northern Patagonia, Argentina.^[1] It is the second formation in the Río Limay Subgroup, the oldest subgroup within the Neuquén Group. Formerly, that subgroup was treated as a formation, and the Huincul Formation was known as the Huincul Member.^[2]

Description

The type locality of the Huincul Formation is near the town of Plaza Huincul in Neuquén Province after which the formation was named by Wichmann in 1929.^[3] This formation conformably overlies the Candeleros Formation, and it is in turn overlain by the Lisandro Formation.

The Huincul Formation is thought to represent an arid environment with ephemeral or seasonal streams.^[4] In some areas, it is up to 250 metres (820 ft) thick. It is mainly composed of green and yellow sandstones and can easily be differentiated from the overlying Lisandro Formation, which is red in color. The Candeleros Formation, underlying the Huincul, is composed of darker sediments, making all three formations easily distinguishable.^[2][5]

Paleobiota

Fauna of Huincul Formation

Dinosaur fossils are frequently found in the Huincul Formation. The titanosaurian sauropod Argentinosaurus huinculensis, one of the largest known land animals, is named after the formation.^[2] Another noteworthy Huincul dinosaur is the carcharodontosaurid theropod Mapusaurus roseae, which is regarded as one of the largest known terrestrial predators.^[4]

Dinosaurs

Apart from sauropods and theropods, rare fossils of iguanodonts and other ornithopods have been recorded in the formation.^[6] Ichnofossils (footprints) of abelisaurid theropods and hadrosaurs are also known.^[7]

Ornithischians

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Ornithischians of the Huincul Formation
Taxa	Species	Locality	Stratigraphic unit	Material	Notes	Images
Chakisaurus[8]	C. nekul	Pueblo Blanco Natural Reserve	Lower[9][10]	Multiple partial skeletons belonging to individuals of different ages	An elasmarian ornithopod; the first ornithischian named from the Huincul Formation

Sauropods

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Sauropods of the Huincul Formation
Genus	Species	Locality	Stratigraphic unit	Material	Notes	Images
Argentinosaurus	A. huinculensis	Las Overas	Upper	Seven dorsal vertebrae, partial sacrum, partial dorsal rib, fibula, and potentially other hindlimb bones	One of the largest titanosaurs known from relatively complete remains
Astigmasaura[11]	A. genuflexa	El Orejano	Lower	A partial articulated skeleton including tail vertebrae, the pelvic girdle, and both hindlimbs	A rebbachisaurid
Bustingorrytitan	B. shiva	Villa El Chocón	Lower	Four specimens are known, including dentary and postcranial skeleton parts.	A titanosaur
Cathartesaura	C. anaerobica[12]	La Buitrera	Lower	A partial skeleton consisting of vertebrae and limb bones.	A rebbachisaurid
Choconsaurus	C. baileywillisi[13]	Villa El Chocón	Lower	Partial skeleton without a skull, MMCh-PV 44/10.	A titanosaur
Chucarosaurus	C. diripienda	Violante farm.	Lower[9][10]	A complete left humerus, partial left radius, complete left metacarpal II, left ischium, partial left femur and fibula, partial right tibia, and partial indeterminate metapodial.[14]	A titanosaur
Cienciargentina	C. sanchezi[15]	Villa El Chocon	Lower	Multiple partial skeletons including several vertebrae and limb bones	A rebbachisaurid
Limaysaurus	L. tessonei	Villa El Chocón	Lower	A partial articulated skeleton composed by two sacrals, the first six caudals, pubis and ischium.	A rebbachisaurid	Limaysaurus
Sidersaura	S. marae	Barda Atravesada de Las Campanas	Lower	Multiple partial skeletons including partial pelvic and pectoral girdles, limb bones, and vertebrae	A rebbachisaurid

Theropods

Theropods of the Huincul Formation
Taxa	Species	Locality	Stratigraphic unit	Material	Notes	Images
Aoniraptor	A. liberataem	Violante Farm	Lower[9][10]	Sacral vertebra, six proximal caudal vertebrae, four mid-caudal vertebrae.[16]	Possibly a megaraptoran
Gualicho	G. shinyae	Violante Farm	Lower[9][10]	A partial skeleton lacking the skull along with several veterbraes, ribs, the left shoulder girdle, the left forelimb, the right lower arm, the lower ends of both pubic bones, thighbones, shinbones, calf bones, metatarsi and three toes of the right foot (Holotype MPCN PV 0001).	A theropod of uncertain affinities
Huinculsaurus	H. montesi	Aguada Grande	Upper	Several vertebrae[17]	A noasaurid
Ilokelesia	I. aguadagrandensis	Aguada Grande	Upper	Fragmented skull and the axial, appendicular skeleton.	An abelisaurid	Ilokelesia
Mapusaurus[18]	M. roseae	Cañadón del Gato	Upper (middle section of formation)[19]	A partial skull consisting of an isolated right nasal, along with twelve paratypes based on additional isolated skeletal elements	A carcharodontosaurid
Meraxes	M. gigas[19]	Las Campanas Creek	Lower	A nearly complete skull, pectoral and pelvic elements, partial forelimbs, complete hindlimbs, fragmentary ribs, and cervical and dorsal vertebrae, a sacrum, and several complete caudal vertebrae.	A carcharodontosaurid	Meraxes gigas reconstruction
Overoraptor	O. chimentoi[20]	Violante Farm	Lower[9][10]	Skeletal specimen consists of two phalanges and a metacarpal of the right hand, two hemal arches, the right scapula, the right ulna, a partial ilium, a partial pubis, two metatarsals from each foot, and several phalanges and unguals from the left foot.	A paravian
Skorpiovenator	S. bustingorryi	Bustingorry's Farm	Lower	A partial skeleton	An abelisaurid
Taurovenator[16]	T. violantei[16]	Violante Farm	Lower[9][10]	An isolated right postorbital and a referred partial skeleton.	A carcharodontosaurid
Tralkasaurus	T. cuyi	Violante Farm	Lower [9][10]	An incomplete skeleton ( MPCA-Pv 815), which comprises a maxilla; dorsal, sacral, and caudal vertebrae; cervical ribs; and a badly-preserved pubis.	An abelisaurid

Other reptiles

Apart from the taxa named here, fossils of unnamed squamates and neosuchian crocodyliforms have been discovered in the formation.^[21]

Non-dinosaur reptiles of the Huincul Formation
Genus	Species	Locality	Stratigraphic unit	Material	Notes	Images
Kaikaifilusaurus	K. sp.	Violante's Farm	Lower	Incomplete right dentary[9]	An eilenodontine rhynchocephalian
Patagosphenos[9]	P. watuku	Violante's Farm	Lower	Disarticulated skull with shoulder and limb fragments	An eilenodontine rhynchocephalian
Prochelidella [22]	P. buitreraensis	La Buitrera	Upper	A partial skeleton with a skull, two cervical vertebrae, a partial left humerus, a partial left ulna, a partial left radius, a right pelvic girdle, a nuchal, and a right first costal.	A chelid turtle

Paleoflora

At least forty species of pollen specimens are derived from the taxons of angiosperms (monosulcate, tricolpate, tricolporoidate, and tricolporate), ferns, mosses and gymnosperms discovered within the El Zampa Section of Huincul Formation.^[23]

Angiosperms

Angiosperms of the Huincul Formation
Taxa	Species	Locality	Stratigraphic unit	Material	Notes	Images
Clavatipollenites	C. rotundus	El Zampal Section	Upper	A pollen	A chloranthaceae
Cretacaeiporites	C. scabratus		Upper	A pollen	A trimeniaceae
Dryadopollis	D. argus		Upper	A pollen	A magnoliophyte
Fraxinoipollenites	F. fragilis		Upper	A pollen	A magnoliophyte
Nyssapollenites	N. lanosus		Upper	A pollen	A magnoliophyte
Retimonocolpites	R. peroreticulatus		Upper	A pollen	An angiosperm pollen morphotaxon of uncertain affinities

Bryophytes (Moss)

Mosses of the Huincul Formation
Taxa	Species	Locality	Stratigraphic unit	Material	Notes	Images
Foraminisporis	F. asymmetricus	El Zampa Section	Upper	A pollen	A moss
	F. wonthaggie
Interulobites	I. intrabverrucatus		Upper	A pollen	A moss
Tricolpites	T. variabilis		Upper	A pollen	A bryopside moss
	T. sagax		Upper	A pollen
Taurocusporites	T. segmenta		Upper	A pollen	A moss

Gymnosperms

Gymnosperms of the Huincul Formation
Taxa	Species	Locality	Stratigraphic unit	Material	Notes	Images
Araucariacites	A. australis	El Zampa Section	Upper	A pollen	An araucariaceae
Callialasporites	C. dampieri		Upper	A pollen	A callialasporites
	C. trilobatus
Classopollis	C. martinotti		Upper	A pollen	A cheirolepidiaceae
Cyclusphaera	C. psilata		Upper	A pollen	An araucariaceae
Cycadopites	C. nitidus		Upper	A pollen	A cycadophyte
Equisetosporites	E. evidens		Upper	A pollen	A cycadophyte
	E. irregularis			A pollen
	E. ovatus			A pollen
Microcachryidites	M. antarcticus		Upper	A pollen	A podocarpaceae
Singhia	S. multicostata		Upper	A pollen	A gymnospermopsida

Ferns

Ferns of the Huincul Formation
Taxa	Species	Locality	Stratigraphic unit	Material	Notes	Images
Biretisporites	B. poton	El Zampa Section	Upper	A pollen	A schizaeaceae
Cicatricosisporites	C. dorogensis		Upper	A pollen	A schizaeaceae
Concavissimisporites	C. punctatus		Upper	A pollen	A pteridopsida
Cyathidites	C. australis		Upper	A pollen	A pteridopsida
Echinatisporis	E. longech		Upper	A pollen	A pteridopsida
	E. sp			A pollen
Microreticulatisporites	M. lacunosus		Upper	A pollen	A pteridophyte
	"M. sp"
Polycingulatisporites	P. circulus		Upper	A pollen	A pteridophyte
	P. cf. reduncus
Triporoletes	T. singularis		Upper	A pollen	A pteridophyte
	T. reticula

Other Plants

Other plants of the Huincul Formation
Taxa	Species	Locality	Stratigraphic unit	Material	Notes	Images
Balmeiopsis	B. limbatus	El Zampa Section	Upper	A pollen	A pollen morphotaxon of uncertain affinities
Elateroplicites	E. africaensis		Upper	A pollen	A pollen morphotaxon of uncertain affinities
Leptolepidites	L. proxigranulatus		Upper	A pollen	A lycopsid

See also

• List of fossil sites
• List of dinosaur bearing rock formations

References

1. Huincul Formation at Fossilworks.org
2. Sánchez et al., 2006
3. Wichmann, 1929
4. Coria & Currie, 2006
5. Leanza et al., 2004, p.68
6. Canudo, J. I., Salgado, L., Garrido, A., Carballido, J. L., Aragosaurus-IUCA, G., Lobo, I., Negro, R., & Olsacher, J. A. (2013). Primera evidencia de dinosaurios ornitópodos en la base de la Formación Huincul (Cenomaniense Superior-Turoniense, Cuenca Neuquina, Argentina) First evidence of ornithopod dinosaurs at the base of Huincul Formation (Cenomanian - Upper Turonian, Neuquén Basin, Argentina).
7. Leonardi, 1994, p.30
8. Nogueira, Rodrigo Alvarez; Rozadilla, Sebastián; Agnolín, Federico L.; Garcia Marsà, Jordi A.; Motta, Matias J.; Novas, Fernando E. (2024-03-11). "A new ornithopod from the Upper Cretaceous (Huincul Formation) of Northwestern Patagonia, Argentina. Implications on elasmarian postcranial anatomy". Cretaceous Research. 159 (In press) 105874. Bibcode:2024CrRes.15905874N. doi:10.1016/j.cretres.2024.105874.
9. Gentil, Adriel R.; Agnolin, Federico L.; Garcia Marsà, Jordi A.; Motta, Matias J.; Novas, Fernando E. (2019). "Bridging the gap: Sphenodont remains from the Turonian (Upper Cretaceous) of Patagonia. Palaeobiological inferences". Cretaceous Research. 98: 72–83. Bibcode:2019CrRes..98...72G. doi:10.1016/j.cretres.2019.01.016.
10. "PBDB Collection". Paleobiology Database. Retrieved 2024-08-20.
11. Bellardini, Flavio; Filippi, Leonardo S.; Carballido, Jose L.; Garrido, Alberto C.; Baiano, Mattia A. (2025-06-13). "Side by side with titans: a new rebbachisaurid dinosaur from the Huincul Formation (upper Cenomanian) of Patagonia, Argentina". Cretaceous Research. 176 (in press) 106188. 106188. doi:10.1016/j.cretres.2025.106188.
12. Gallina, Pablo A.; Apesteguía, Sebastián (2005). "Cathartesaura anaerobica gen. et sp. nov.,a new rebbachisaurid (Dinosauria, Sauropoda) from the Huincul Formation (Upper Cretaceous), Rio Negro, Argentina". Revista del Museo Argentino de Ciencias Naturales. Nueva Series. 7 (2): 153–166. doi:10.22179/REVMACN.7.332.
13. Simón, Edith; Salgado, Leonardo; Calvo, Jorge O. (2017). "A new titanosaur sauropod from the Upper Cretaceous of Patagonia, Neuquén Province, Argentina". Ameghiniana. 55: 1–29. doi:10.5710/AMGH.01.08.2017.3051. hdl:11336/89326. Retrieved 2020-03-16.
14. Agnolin, Federico L.; Gonzalez Riga, Bernardo J.; Aranciaga Rolando, Alexis M.; Rozadilla, Sebastián; Motta, Matías J.; Chimento, Nicolás R.; Novas, Fernando E. (2023-02-02). "A new giant titanosaur (Dinosauria, Sauropoda) from the Upper Cretaceous of Northwestern Patagonia, Argentina". Cretaceous Research. 146 105487. Bibcode:2023CrRes.14605487A. doi:10.1016/j.cretres.2023.105487. ISSN 0195-6671.
15. Simón, M. E.; Salgado, L. (2025). "New rebbachisaurid (Dinosauria, Sauropoda) from the Huincul Formation (upper Cenomanian-Turonian) of Villa El Chocón (Neuquén Province, Argentina)". Cretaceous Research. 173 106137. 106137. doi:10.1016/j.cretres.2025.106137.
16. Motta, Matías J.; Aranciaga Rolando, Alexis M.; Rozadilla, Sebastián; Agnolín, Federico E.; Chimento, Nicolás R.; Egli, Federico Brissón; Novas, Fernando E. (June 2016). "New theropod fauna from the Upper Cretaceous (Huincul Formation) of northwestern Patagonia, Argentina". New Mexico Museum of Natural History and Science Bulletin. 71: 231–253 – via ResearchGate.
17. Mattia Baiano; Rodolfo Coria; Andrea Cau (2020). "A new abelisauroid (Dinosauria: Theropoda) from the Huincul formation (lower upper Cretaceous, Neuquén Basin) of Patagonia, Argentina". Cretaceous Research. 110 104408. Bibcode:2020CrRes.11004408B. doi:10.1016/j.cretres.2020.104408.
18. Canale et al., 2012
19. Canale, J.I.; Apesteguía, S.; Gallina, P.A.; Mitchell, J.; Smith, N.D.; Cullen, T.M.; Shinya, A.; Haluza, A.; Gianechini, F.A.; Makovicky, P.J. (2022). "New giant carnivorous dinosaur reveals convergent evolutionary trends in theropod arm reduction". Current Biology. 32 (14): 3195–3202.e5. Bibcode:2022CBio...32E3195C. doi:10.1016/j.cub.2022.05.057. PMID 35803271.
20. Matías J. Motta; Federico L. Agnolín; Federico Brissón Egli; Fernando E. Novas (2020). "New theropod dinosaur from the Upper Cretaceous of Patagonia sheds light on the paravian radiation in Gondwana". The Science of Nature. 107 (3) 24. Bibcode:2020SciNa.107...24M. doi:10.1007/s00114-020-01682-1. hdl:11336/135530. PMID 32468191. S2CID 218913199.
21. Motta, M.J.; Brissón Egli, F.; Aranciaga Rolando, A.M.; Rozadilla, S.; Gentil, A. R.; Lio, G.; Cerroni, M.; Garcia Marsà, J.; Agnolín, F. L.; D'Angelo, J. S.; Álvarez-Herrera, G. P.; Alsina, C.H.; Novas, F.E. (2019). "New vertebrate remains from the Huincul Formation (Cenomanian–Turonian;Upper Cretaceous) in Río Negro, Argentina". Publicación Electrónica de la Asociación Paleontológica Argentina. 19 (1): R26. doi:10.5710/PEAPA.15.04.2019.295. hdl:11336/161858. S2CID 127726069. Archived from the original on December 14, 2019. Retrieved December 14, 2019.
22. Maniel, Ignacio J.; de la Fuente, Marcelo S.; Apesteguía, Sebastián; Pérez Mayoral, Joaquin; Sanchez, Maria L.; Veiga, Gonzalo D.; Smales, Ian (2020-02-24). "Cranial and postcranial remains of a new species of Prochelidella (Testudines: Pleurodira: Chelidae) from 'La Buitrera' (Cenomanian of Patagonia, Argentina), with comments on the monophyly of this extinct chelid genus from southern Gondwana". Journal of Systematic Palaeontology. 18 (12): 1033–1055. Bibcode:2020JSPal..18.1033M. doi:10.1080/14772019.2020.1721579. S2CID 214500365. Retrieved 2020-07-11.
23. Vallati, P. (2001). Middle Cretaceous Microflora from the Huincul Formation (“Dinosaurian Beds”) in the Neuquén Basin, Patagonia, Argentina. Palynology, 25, 179–197. http://www.jstor.org/stable/3687705

Bibliography

• Canale, Juan Ignacio; Apesteguía, Sebastián; Makovicky, Peter; Gallina, Pablo Ariel; Gianechini, Federico; Smith, Natan; Maniel, Ignacio; Haluza, Alejandro (2012). "New carcharodontosaurid theropod remains from El Chocón Neuquén Group, Huincul Formation, Neuquén, Argentina". Ameghiniana. 50.
• Coria, R.A.; Currie, P.J. (2006). "A new carcharodontosaurid (Dinosauria, Theropoda) from the Upper Cretaceous of Argentina". Geodiversitas. 28: 71–118. Retrieved 2019-02-16.
• Leanza, H.A.; Apesteguia, S.; Novas, F.E.; De la Fuente, M.S. (2004). "Cretaceous terrestrial beds from the Neuquén Basin (Argentina) and their tetrapod assemblages". Cretaceous Research. 25 (1): 61–87. Bibcode:2004CrRes..25...61L. doi:10.1016/j.cretres.2003.10.005. Retrieved 2019-02-16.
• Leonardi, Giuseppe (1994). "Annotated Atlas of South America Tetrapod Footprints (Devonian to Holocene) with an appendix on Mexico and Central America". Ministerio de Minas e Energia - Companhia de Pesquisa de Recursos Minerais, Geological Service of Brazil. pp. 1–248. Retrieved 2019-03-25.
• Sánchez, María Lidia; Heredia, Susana; Calvo, Jorge O. (2006). "Paleoambientes sedimentarios del Cretácico Superior de la Formación Plottier (Grupo Neuquén), Departamento Confluencia, Neuquén" [Sedimentary paleoenvironments in the Upper Cretaceous Plottier Formation (Neuquen Group), Confluencia, Neuquén)]. Revista de la Asociación Geológica Argentina. 61: 3–18. Retrieved 2019-02-16.
• Wichmann, R (1929). "Los Estratos con Dinosaurios y su techo en el este del Territorio del Neuquén ("The dinosaur-bearing strata and their upper limit in eastern Neuquén Territory")". Dirección General de Geología, Minería e Hidrogeología Publicación. 32: 1–9.