Los Alamitos Formation

Last updated
Los Alamitos Formation
Stratigraphic range: Late Campanian-Maastrichtian
~85–66  Ma
Type Geological formation
Sub-units Coli Toro Member
Lithology
Primary Siltstone
Other Sandstone
Location
Coordinates 42°06′S66°18′W / 42.1°S 66.3°W / -42.1; -66.3
Approximate paleocoordinates 45°00′S52°18′W / 45.0°S 52.3°W / -45.0; -52.3
Region Río Negro Province
CountryArgentina
Extent North Patagonian Massif
Relief Map of Argentina.jpg
Green pog.svg
Los Alamitos Formation (Argentina)

The Los Alamitos Formation is a geological formation of the North Patagonian Massif in Rio Negro Province, northwestern Patagonia, Argentina, whose strata date back to the Late Cretaceous (Late Campanian to Maastrichtian). Dinosaur remains are among the fossils that have been recovered from the formation. [1]

Contents

Fossil content

Paleogeography of the Late Cretaceous with Los Alamitos Formation indicated Paleogeography Gondwana - Late Cretaceous-Early Paleogene - around 85-63 Ma.jpg
Paleogeography of the Late Cretaceous with Los Alamitos Formation indicated

Dinosaurs

GenusSpeciesMaterialNotesImages
Aeolosaurus A. rionegrinusA titanosaur.
Aeolosaurus-rionegrinus-JD-2020-1.png
Alamitornis A. minutusAn ornithuromorph.
Huallasaurus H. australis"Partial skulls with associated postcrania, approximately [five] individuals."A hadrosaur formally named "Kritosaurus" australis .
Hadrosaur museum.jpg
cf. Hesperornithes
Indeterminate theropod
Indeterminate ornithurine
Indeterminate avian

Rhynchocephalians

GenusSpeciesMaterialNotesImages
Alamitosphenos A. mineri
[5]

Snakes

GenusSpeciesMaterialNotesImaes
Alamitophis A. elongatus

Mammaliaforms

GenusSpeciesMaterialNotesImages
Alamitherium A. bishopi
[6]
Austrotriconodon A. sepulvedai
A. mckennai
Leonardus L. cuspidatus
Bondesius B. ferox
Brandonia B. intermedia
Casamiquelia C. rionegrina
Ferugliotherium F. windhauseni
Gondwanatherium G. patagonicum
Groebertherium G. novasi
Mesungulatum M. houssayi
[7]
Paraungulatum P. rectangularis
Reigitherium R. bunodontum
[8]
Rougiertherium R. tricuspes

See also

Related Research Articles

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<i>Megaraptor</i> Extinct genus of dinosaurs

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<i>Secernosaurus</i> Extinct genus of dinosaurs

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<span class="mw-page-title-main">Allen Formation</span> Geological formation in Argentina

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<span class="mw-page-title-main">Chorrillo Formation</span> Geologic formation in southern Patagonia, Argentina

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<i>Bonapartenykus</i> A large alvarezsauroid dinosaur

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<span class="mw-page-title-main">Kritosaurini</span> Extinct clade of dinosaurs

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<span class="mw-page-title-main">Elasmaria</span> Extinct clade of dinosaurs

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<i>Niebla antiqua</i> Extinct species of dinosaur

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<i>Huallasaurus</i> Extinct genus of dinosaur

Huallasaurus is an extinct genus of saurolophine hadrosaur from the Late Cretaceous Los Alamitos Formation of Patagonia in Argentina. The type and only species is H. australis. Originally named as a species of Kritosaurus in 1984, it was long considered a synonym of Secernosaurus before being recognized as its own distinct genus in a 2022 study, different from other members of Kritosaurini.

<i>Kelumapusaura</i> Extinct genus of dinosaur

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<i>Maip</i> Genus of megaraptoran dinosaurs

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<i>Meraxes</i> Genus of carcharodontosaurid dinosaurs

Meraxes is a genus of large carcharodontosaurid theropod dinosaur from the Late Cretaceous Huincul Formation of Patagonia, Argentina. The genus contains a single species, Meraxes gigas.

<i>Patagopelta</i> Genus of nodosaurid dinosaurs

Patagopelta is an extinct genus of ankylosaurian dinosaur from the Late Cretaceous Allen Formation of Argentina. The genus contains a single species, P. cristata, known from a partial skeleton. While originally described as a nodosaurine, later discoveries provided support for parankylosaurian affinities for the taxon. Patagopelta is a very small ankylosaur, comparable in size to the dwarf nodosaurid Struthiosaurus, about 2 m (6.6 ft) long.

<i>Yatenavis</i> Extinct genus of birds

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<i>Chucarosaurus</i> Genus of titanosaurian dinosaurs

Chucarosaurus is an extinct genus of titanosaurian dinosaur from the Late Cretaceous Huincul Formation of Argentina. The genus contains a single species, C. diripienda, known from various limb and pelvic bones.

<i>Chakisaurus</i> Extinct genus of ornithopod dinosaurs

Chakisaurus is an extinct genus of elasmarian ornithopod dinosaur from the Late Cretaceous Huincul Formation of Argentina. The genus contains a single species, C. nekul, known from multiple partial skeletons belonging to individuals of different ages. Chakisaurus represents the first ornithischian species to be named from the Huincul Formation.

References

  1. Weishampel et al., 2004, "Dinosaur distribution (Late Cretaceous, South America).", pp.600-604
  2. Rozadilla, Sebastián; Brissón-Egli, Federico; Lisandro Agnolín, Federico; Aranciaga-Rolando, Alexis Mauro; Novas, Fernando Emilio (2022). "A new hadrosaurid (Dinosauria: Ornithischia) from the Late Cretaceous of northern Patagonia and the radiation of South American hadrosaurids". Journal of Systematic Palaeontology. 19 (17): 1207–1235. doi:10.1080/14772019.2021.2020917. S2CID   247122005.
  3. Prieto–Marquez, Alberto; Salinas, Guillermo C. (2010). "A re–evaluation of Secernosaurus koerneri and Kritosaurus australis (Dinosauria, Hadrosauridae) from the Late Cretaceous of Argentina". Journal of Vertebrate Paleontology. 30 (3): 813–837. doi:10.1080/02724631003763508. S2CID   85814033.
  4. "Table 20.1," in Weishampel, et al.
  5. Agnolín, F. L.; Aranciaga Rolando, A. M.; Chimento, N. R.; Novas, F. E. (2023). "New small reptile remains from the Late Cretaceous of Patagonia increase morphological diversity of sphenodontids (Lepidosauria)". Proceedings of the Geologists' Association. doi:10.1016/j.pgeola.2023.09.007.
  6. Bonaparte, 1999
  7. Bonaparte & Soria, 1985
  8. Bonaparte, 1990

Bibliography