Leyesaurus

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Leyesaurus
Temporal range: Early Jurassic
~202–176  Ma
Leyesaurus skull in lateral view.png
Skull of Leyesaurus marayensis in lateral view
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Sauropodomorpha
Family: Massospondylidae
Genus: Leyesaurus
Apaldetti et al. 2011
Species:
L. marayensis
Binomial name
Leyesaurus marayensis
Apaldetti et al. 2011

Leyesaurus is an extinct genus of massospondylid sauropodomorph dinosaur known from the San Juan Province, northwestern Argentina. [1]

Contents

Description

Silhouette reconstruction of the skeleton of L. marayensis Leyesaurus silhouette.png
Silhouette reconstruction of the skeleton of L. marayensis
Skull of L. marayensis in dorsal view Leyesaurus skull in dorsal view.png
Skull of L. marayensis in dorsal view

Leyesaurus is known from the holotype PVSJ  706, a nearly complete skull with articulated mandible and some postcranial remains (vertebral column, scapular and pelvic girdles and hindlimb). The skull has a length of 18 centimeters, and Leyesaurus has been estimated to have been about 2.5 m (8.2 ft) in length. It was collected from the uppermost part of the Quebrada del Barro Formation of the Marayes-El Carrizal Basin, dating to the Lower Jurassic (based on the similarities between Leyesaurus and Lower Jurassic sauropodomorphs, like Massospondylus and Adeopapposaurus ). Leyesaurus was found near the locality Balde de Leyes, in the Caucete Department of San Juan Province. Within Massospondylidae, Leyesaurus was found to be most closely related to Adeopapposaurus . [1]

Etymology

Leyesaurus was first named by Cecilia Apaldetti, Ricardo N. Martinez, Oscar A. Alcober and Diego Pol in 2011 and the type species is Leyesaurus marayensis. The generic name honors the Leyes family, inhabitants of the small town Balde de Leyes, who discovered the holotype and notified the paleontologists of the San Juan Museum, and saurus, Greek for "lizard". The specific name refers to the Marayes-El Carrizal Basin, where the holotype was discovered. [1]

Phylogeny

The following cladogram shows the position of Leyesaurus within Massopoda, according to Oliver W. M. Rauhut and colleagues, 2020: [2]

Massopoda

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References

  1. 1 2 3 Cecilia Apaldetti; Ricardo N. Martinez; Oscar A. Alcober & Diego Pol (2011). Claessens, Leon (ed.). "A New Basal Sauropodomorph (Dinosauria: Saurischia) from Quebrada del Barro Formation (Marayes-El Carrizal Basin), Northwestern Argentina". PLOS ONE. 6 (11): e26964. Bibcode:2011PLoSO...626964A. doi: 10.1371/journal.pone.0026964 . PMC   3212523 . PMID   22096511.
  2. Rauhut, O. W. M.; Holwerda, F. M.; Furrer, H. (2020). "A derived sauropodiform dinosaur and other sauropodomorph material from the Late Triassic of Canton Schaffhausen, Switzerland". Swiss Journal of Geosciences . 113 (1): 8. doi: 10.1186/s00015-020-00360-8 . S2CID   220294939.