Argentinosaurus

from Wikipedia, the free encyclopedia
Argentinosaurus
Replica of the reconstructed skeleton at a special exhibition at the Senckenberg Nature Museum

Replica of the reconstructed skeleton at a special exhibition at the Senckenberg Nature Museum

Temporal occurrence
Upper Cretaceous ( Cenomanium )
100.5 to 93.9 million years
Locations
Systematics
Dinosaur (dinosauria)
Sauropods (Sauropoda)
Macronaria
Titanosaurs (Titanosauria)
Argentinosaurus
Scientific name
Argentinosaurus
Bonaparte & Coria , 1993
Art
  • Argentinosaurus huinculensis
Artistic live representation of Argentinosaurus in size comparison with a human

Argentinosaurus is a genus of sauropod dinosaurs from the Titanosauria group .

So far, only very fragmentary remains are known from the early Upper Cretaceous ( Cenomanium ) of the Argentine province of Neuquén .

Argentinosaurus is one of the largest known sauropods and thus one of the largest known land animals in the history of the earth - current estimates assume a length of 30 meters and a weight of around 73 tons. The only known species is Argentinosaurus huinculensis .

features

Few bones have been found so far. The holotype material includes three anterior and three posterior vertebrae, the lower areas of the vertebral bodies of five sacral vertebrae, most of the right sacral ribs, most of a fragmentary dorsal rib, and the right shinbone (tibia). Furthermore, an incomplete thigh bone (femur) was attributed to Argentinosaurus (specimen number MLP-DP 46-VIII-21-3), which has a length of 1.18 meters. In total, 10% of the entire skeleton is fossilized

The vertebrae are up to 1.59 meters high, measured from the spinous processes to the underside of the vertebral bodies, while the vertebral bodies have diameters of approximately 50 centimeters. The shin is about 1.55 meters long.

An early reconstruction by Gregory Paul estimates Argentinosaurus to be 30 to 35 meters long and 80 to 100 tons in weight. Other researchers base their size estimates on the physique of better-known, related genera and assume that Argentinosaurus exhibited similar proportions. Carpenter (2006) used the more fully known Saltasaurus as a reference and estimated Argentinosaurus to be 30 meters in length. Weight estimates are generally more difficult and are done less often. However, researchers working with Mazzetta (2004) calculated that the weight was between 60 and 88 tons, and give 73 tons as the most likely value, which makes Argentinosaurus the heaviest sauropod known from relatively good fossils.

The dorsal vertebrae of the sauropods showed additional mechanical connecting elements , the hyposphene-hypantrum connections . These connections stabilized the spine and thus probably supported the gigantic stature of the sauropods, but at the same time restricted the mobility of the spine. In most Titanosauria, including Argentinosaurus , these connecting elements have been lost in favor of a more flexible spine. In Argentinosaurus and in a similar form also in Epachthosaurus , novel connecting elements have developed secondarily analogous to the hyposphene-hypantrum connections; probably as a result of increasing body size.

Argentinosaurus can be distinguished from other genera by the novel connecting elements of the vertebrae (see above) and by the tubular ribs.

Systematics

The position of this genus within the Titanosauria is controversial. The first descriptors (Bonaparte and Coria, 2003) classified Argentinosaurus together with Andesaurus within a family of original titanosaurs, the Andesauridae, which should oppose the more advanced Titanosauridae. Today the Andesauridae is considered paraphyletic and therefore invalid. Upchurch and colleagues (2004) also see Argentinosaurus as a more original representative of the Titanosauria, and classify it outside of the Lithostrotia (= Titanosauridae). Curry Rogers (2005), however, sees Argentinosaurus as a representative of a group of very progressive Titanosauria, the Opisthocoelicaudiinae. In this group she summarizes Argentinosaurus , Isisaurus , Alamosaurus , Opisthocoelicaudia and Antarctosaurus .

History of discovery and naming

Fragmentary thigh bone in the Argentine Museo de la Plata

The fossils were collected by employees of the Carmen Funes Museum inside the Las Overas farm in the city of Plaza Huincul . While initially only one shin was excavated, the remaining fossils were recovered in the summer of 1989.

The site belongs to the Huincul Formation , a layer member of the Río Limay subgroup of the Neuquén group . This rock unit used to be subordinate to the Río Limay Formation as a Huincul member.

Argentinosaurus was first scientifically described in 1993 by the Argentine paleontologists José Fernando Bonaparte and Rodolpho Coria . The name Argentinosaurus ( Latin for Argentine lizard ) points to the country of Argentina, while the second part of the species name, huinculensis , points to the town of Plaza Huincul, where the fossils were found.

Web links

Commons : Argentinosaurus  - collection of images, videos and audio files

Individual evidence

  1. ↑ Fernando E. Novas , Leonardo Salgado , Jorge Calvo , Federico Agnolin: Giant titanosaur (Dinosauria, Sauropoda) from the late Cretaceous of Patagonia. In: Revista del Museo Argentino de Ciencias Naturales. Vol. 7, No. 1, 2005, ISSN  1514-5158 , pp. 37-41, digitized version (PDF; 2.5 MB) .
  2. ↑ a b Kenneth Carpenter : Biggest of the big: a critical re-evaluation of the mega-sauropod Amphicoelias fragillimus Cope, 1878. In: John R. Foster, Spencer G. Lucas (eds.): Paleontology and Geology of the Upper Jurassic Morrison Formation (= New Mexico Museum of Natural History & Science. Bulletin. 36, ISSN  1524-4156 ). New Mexico Museum of Natural History & Science, Albuquerque NM 2006, pp. 131-138, online .
  3. ^ A b c Gerardo V. Mazzetta, Per Christiansen, Richard A. Fariña: Giants and Bizarres: Body Size of Some Southern South American Cretaceous Dinosaurs. In: Historical Biology. Vol. 16, No. 2/4, 2004, ISSN  0891-2963 , pp. 71-83, doi : 10.1080 / 08912960410001715132 , digital version (PDF; 574.66 kB) .
  4. ↑ Jorge O. Calvo, Juan D. Porfiri, Bernardo J. González Riga, Alexander WA Kellner: Anatomy of Futalognkosaurus dukei Calvo, Porfiri, González Riga, & Kellner, 2007 (Dinosauria, Titanosauridae) from the Neuquen Group, Late Cretaceous, Patagonia , Argentina. In: Arquivos do Museu Nacional. Vol. 65, No. 4, 2007, ISSN  0365-4508 , pp. 511-526, digitized version (PDF; 21.68 MB) ( Memento from July 30, 2014 in the Internet Archive ).
  5. ↑ a b c d e José F. Bonaparte, Rodolfo A. Coria: Un nuevo y gigantesco sauropodo titanosaurio de la Formacion Rio Limay (Albiano-Cenomaniano) de la Provincia del Neuquen, Argentina. In: Ameghiniana . Vol. 30, No. 3, 1993, pp. 271-282, online .
  6. ^ A b c Paul Upchurch , Paul M. Barrett , Peter Dodson : Sauropoda. In: David B. Weishampel , Peter Dodson, Halszka Osmólska (eds.): The Dinosauria . 2nd edition. University of California Press, Berkeley CA et al. 2004, ISBN 0-520-24209-2 , pp. 259-324.
  7. ↑ Gregory S. Paul : Big Sauropods - Really, Really Big Sauropods. In: The Dinosaur Report. Fall 1994, pp. 12-13, digitized version (PDF; 2.12 MB) .
  8. ^ Gregory S. Paul: Dinosaur models: the good, the bad, and using them to estimate the mass of dinosaurs. In: Donald L. Wolberg, Edmund Stump, Gary Rosenberg (Eds.): Dinofest International. Proceedings of a Symposium held at Arizona State University. Academy of Natural Sciences, Philadelphia PA 1997, ISBN 0-935868-94-1 , pp. 129-154, digitized version (PDF; 13.26 MB) .
  9. ↑ Sebastián Apesteguía: Evolution of the Hyposphene-Hypantrum Complex within Sauropoda. In: Virginia Tidwell, Kenneth Carpenter (Eds.): Thunder-lizards. The Sauropodomorph Dinosaurs. Indiana University Press, Bloomington IN et al. 2005, ISBN 0-253-34542-1 , pp. 248-267.
  10. ↑ Leonardo Salgado, Rodolfo A. Coria, Jorge O. Calvo: Evolution of Titanosaurid Sauropods. I: Phylogenetic Analysis Based on the Postcranial Evidence. In: Ameghiniana. Vol. 34, No. 1, 1997, pp. 3–32, digitized version (PDF; 4.42 MB) ( Memento from March 9, 2012 in the Internet Archive ).
  11. ↑ Kristina Curry Rogers: Titanosauria: A Phylogenetic Overview. In: Kristina Curry A. Rogers, Jeffrey A. Wilson (Eds.): The Sauropods. Evolution and Paleobiology. University of California Press, Berkeley CA et al. 2005, ISBN 0-520-24623-3 , pp. 50-103, doi : 10.1525 / california / 9780520246232.003.0003 .