Acostasaurus is an extinct genus of thalassophonean pliosaurid known from the Early Cretaceous, Paja Formation, Colombia.
Description[]
The type specimen, UNDG R-1000, is known from a near complete skull, and postcranial elements including a complete hindlimb and various vertebrae. The specimen has an estimated size of around 4 to 5 metres (13 to 16 ft) long. Its name means 'Acosta's lizard'. The type specimen is noted for possessing several features that pertain to a sub adult individual: for example, the sagittal crest is not fully ossified, as well as possessing undeveloped palatine wings.
It is presumed that Acostasaurus, similiar to other plesiosaur species, was paedomorphic. From the observable evidence; the orbits are large, rounded and deeply notched dorsally. The sclerotic ring of the specimen is also very large, suggesting that Acostasaurus was adapted to see in deep or murky waters.
As brachauchenine pliosaurs are the only pliosaurids known from the Barremian stage, especially from Colombia, Gómez Pérez et al. compared Acostasaurus to a variety of brachauchenine taxa in the paper. The authors however concluded that referral of the genus to the subfamily is problematic.
References[]
- https://www.researchgate.net/publication/322007832_Cranial_anatomy_of_a_new_pliosaurid_Acostasaurus_pavachoquensis_from_the_Lower_Cretaceous_of_Colombia_South_America
- https://www.schweizerbart.de/papers/pala/detail/310/88332/Cranial_anatomy_of_a_new_pliosaurid_Acostasaurus_pavachoquensis_from_the_Lower_Cretaceous_of_Colombia_South_America
- https://www.cambridge.org/core/journals/geological-magazine/article/abs/morphological-and-phylogenetic-aspects-of-the-dentition-of-megacephalosaurus-eulerti-a-pliosaurid-from-the-turonian-of-kansas-usa-with-remarks-on-the-cranial-anatomy-of-the-taxon/92E9DD09EBFE177F7C569216240DAF13
- http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S1794-61902018000400223