Candeleros Formation
Candeleros Formation | ||
---|---|---|
Ma | ||
Approximate paleocoordinates 46°30′S 45°30′W / 46.5°S 45.5°W | | |
Region | Mendoza, Neuquén & Río Negro Provinces | |
Country | Argentina | |
Extent | Neuquén Basin | |
Type section | ||
Named for | Candeleros Hill | |
Named by | Wichmann | |
Year defined | 1929 | |
The Candeleros Formation (formerly known as the Candeleros Member of the "Río Limay Formation") is a
Description
The type locality of the Candeleros Formation is Candeleros Hill in Neuquén Province, after which the formation was named by Wichmann in 1929.[2] This formation unconformably overlies the Lohan Cura Formation, and it is in turn overlain by the Huincul Formation, also a unit of the Neuquén Group. The sediments of the latter are of lighter greenish and yellow colors and the boundary between the Candeleros and Huincul formations is easily recognizable.[3]
The Candeleros Formation is almost 300 metres (980 ft) thick in some sections. Overall, the formation represents a part of the ancient Kokorkom desert with braided river system, made up mostly of sandstones and conglomerates. There are also isolated sections that represent eolian (wind-blown) deposition, as well as siltstones deposited under swamp conditions. Paleosols (soil deposits) are common in some sections as well.[1][3]
Fossil content
The Candeleros Formation has a very diverse fossil fauna, including:
- Ceratodus argentinus)
- frogs (including Avitabatrachus)
- Rhynchocephalians (including Priosphenodon avelasi and Tika giacchinoi)
- primitive Najash rionegrina)
- several turtles (including 2 species of Prochelidella)
- an azhdarchid pterosaur, the oldest known from South America[4]
- )
- titanosaurian sauropods (including Andesaurus and a second unnamed huge titanosaur)
- theropods (Ekrixinatosaurus and unnamed form[5])
- a carcharodontosaurid (Giganotosaurus)
- a Buitreraptor gonzalezorum)
- an alvarezsauroid theropod (Alnashetri)
- a basal coelurosaur (Bicentenaria)
- Iguanodonts (including Bonaparteichnium)[6]
- a notosuchian (Araripesuchus)
- a basal thyreophoran (Jakapil)[7]
- cladotherian mammals (including Cronopio dentiacutus)
- Picunichnus benedettoi[8]
In 2021, fossil material of a giant titanosaur sauropod, distinct from Andesaurus and probably exceeding Patagotitan in size, was described from the formation by Otero et al. (2021).[9]
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Amphibians
- Frogs
Taxa | Species | Locality | Stratigraphic position | Material | Notes | Images |
---|---|---|---|---|---|---|
Avitabatrachus[10] | A. uliana | El Gigante. | Río Limay Subgroup of the Neuquén Group. | Fragmented skull and postcranial skeleton. | A Pipimorpha frog.
|
Reptiles
- Rhynchocephalians
Taxa | Species | Locality | Stratigraphic position | Material | Notes | Images |
---|---|---|---|---|---|---|
Priosphenodon | P. avelasi | An eilenodontine rhynchocephalian. | ||||
Tika | T. giacchinoi | A sphenodontine rhynchocephalian. |
Fish
Taxa | Species | Locality | Stratigraphic position | Material | Notes | Images |
---|---|---|---|---|---|---|
Ceratodus
|
C. argentinus | A lungfish. |
Dinosaurs
Ornithischians
Taxa | Species | Locality | Stratigraphic position | Material | Notes | Images |
---|---|---|---|---|---|---|
Bonaparteichnium | B. tali | Footprints. | An Iguanodont. | |||
Jakapil[7] | J. Kaniukura | La Buitrera, Cerro Policía, La Escondida and El Pueblito. | MPCA-PV-630, a partial skeleton including several osteoderms and a complete lower jaw. | A basal thyreophoran. |
Saurischians
Color key
|
Notes Uncertain or tentative taxa are in small text; |
- Sauropods
Taxa | Species | Locality | Stratigraphic position | Material | Notes | Images |
---|---|---|---|---|---|---|
Andesaurus | A. delgadoi | A partial skeleton. | A titanosaur. | |||
Limaysaurus | L. tessonei | A rebbachisaurid sauropod. | ||||
Nopcsaspondylus | N. alarconensis | A rebbachisaurid sauropod. | ||||
Rayososaurus | R. agrioensis | A rebbachisaurid sauropod. | ||||
Titanosauria | indeterminate. |
- Theropods
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Taxa | Species | Locality | Stratigraphic position | Material | Notes | Images |
---|---|---|---|---|---|---|
Abelichnus | A. astigerrae | A footprint. | ||||
Alnashetri | A. cerropoliciensis | La Buitrera | Rio Negro | The holotype consists of a partial left femur, distal portions of left and right tibiae, right fibula, proximal tarsals of both ankles, a nearly complete right metatarsus, proximal and distal parts of the left metapodials, and left pedal digit III. | An alvarezsauroid theropod. | |
Bicentenaria | B. argentina | Ezequiel Ramos Mexia Reservoir | Rio Negro province. | Several paratypes consist of fragments of two premaxillae with three pairs of teeth; a piece of upper right jawbone with a tooth; pieces of seventeen vertebrae; fourteen sacral vertebrae; twenty caudal vertebrae; pieces of two shoulder blades; an upper back corner of a right raven's jawbone; the tops of three ulna; the end of a spoke bone; eight hand claws; pieces of a left femur; five upper shafts of pubic bones; five partial femurs; the tops of two left tibias; the underside of a right tibia; a right tibia; pieces of five metatarsals; fifteen phalanges, separately eight-foot claws and pieces of rib. | A coelurosaur. | |
Buitreraptor | B. gonzalezorum | La Buitrera | Rio Negro province. | A partial skeleton along with several other paratypes such as a sacrum with a right pelvis, right hindlimb, and a skull. | A dromaeosaurid theropod. | |
Ekrixinatosaurus | E. novasi | Bajo del Añelo | Río Negro, Neuquén and Mendoza provinces. | A preserved skeleton. | An Abelisaurid theropod. | |
Giganotosaurus | G. carolinii | Los Candeleros, and Villa El Chocón. | Lowest unit in the Neuquén Group. | A partial skull, and a disarticulated postcranial skeleton which includes a vertebral column, pectoral and pelvic girdles, the femora, and the left tibia and fibula. | A carcharodontosaurid theropod.
|
Mammals
Taxa | Species | Locality | Stratigraphic position | Material | Notes | Images |
---|---|---|---|---|---|---|
Cronopio | C. dentiacutus | La Buitrera. | Neuquén Group. | Paratypes consist of a partial skull without skull roof, basicranium, and squamosals, a partial left lower jaw with damaged teeth, and an incomplete skull with a relatively complete right lower jaw missing some teeth. | A small insectivorous mammal that belongs to the Meridiolestida family. |
Reptiles
Taxa | Species | Locality | Stratigraphic position | Material | Notes | Images |
---|---|---|---|---|---|---|
Araripesuchus | A. buitreraensis | A small Crocodyliform reptile.
|
||||
A. patagonicus | ||||||
Prochelidella | P. buitreraensis | La Buitrera. | Rio Negro province. | A complete cranium skull. | A chelid tortoise.
|
|
Najash | N. rionegrina | A basal snake. |
See also
- List of fossil sites
- San Jorge Basin
- Cerro Fortaleza Formation, contemporaneous fossiliferous formation of the Austral Basin
- Alcântara Formation, contemporaneous fossiliferous formation of the São Luís-Grajaú Basin, Brazil
- List of dinosaur bearing rock formations
References
- ^ a b Sánchez et al., 2006
- ^ Wichmann, 1929
- ^ a b Leanza et al., 2004
- ISSN 1853-0400.
- ^ Canale et al., 2016
- ^ Calvo, Jorge O. (1991). "Huellas de dinosaurios en la Formación Río Limay (Albiano-Cenomaniano?), Picún Leufú, Provincia del Neuquén, República Argentina (Ornithischia-Saurischia: Sauropoda-Theropoda)". Ameghiniana. 28 (3): 241–258.
- ^ PMID 35953515.
- ^ Leonardi, 1994, p. 79
- ^ Otero et al., 2021
- ^ Baez, Ana & Trueb, Linda & Calvo, Jorge. (2000). The earliest known pipoid frog from South America: A new genus from the Middle Cretaceous of Argentina. Journal of Vertebrate Paleontology. 20. 490-500. 10.1671/0272-4634(2000)020%5B0490:TEKPFF%5D2.0.CO;2.
Bibliography
- Otero, A.; Carballido, J. L.; Salgado, L.; Canudo, J. I.; Garrido, A. C. (2021). "Report of a giant titanosaur sauropod from the Upper Cretaceous of Neuquén Province, Argentina".
- Canale, Juan I.; Cerda, Ignacio;
- 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.
- Leanza, H.A.; Apesteguia, S.; . 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.
- 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.