Yarasuchus

Yarasuchus
Temporal range: Middle Triassic, Anisian
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
informal group: Rauisuchia
Node: Paracrocodylomorpha
Branch: Poposauroidea
Genus: Yarasuchus
Sen, 2005
Species
  • Y. deccanensis Sen, 2005 (type)

Yarasuchus is an extinct genus of rauisuchian, a group of predatory and large Triassic archosaurs. It lived during the Anisian stage of the Middle Triassic of India.[1] Being only 2 metres long, is was one of the smallest rauisuchians known. The genus was named and described in 2005 from incomplete fossil material found from the Middle Triassic Yerrapalli Formation, thought to be from two individuals, with one being much more complete and articulated than the other.[2] The type and only species is Y. deccanensis.

Contents

Description

The cervical vertebrae that make up the neck of Yarasuchus are characteristically elongated, while the skull is proportionally small. The genus is also distinguished from other prestosuchids by a delicately built pectoral girdle and a continuous acromion process of the scapula. The neural spines of the vertebrae are high and the paramedian osteoderms are greatly sculptured with a ridge running anteroposteriorly along each one.[2]

Paleobiology

Yarasuchus may have had a facultatively bipedal gait.[2]

Many other vertebrate remains have been found from the Yerrapalli Formation alongside those of Yarasuchus, and would have coexisted with the genus during the Middle Triassic. Remains of the prolacertiform Pamelaria dolichotrachela have been found in close proximity to those of Yarasuchus.[3] Other vertebrate remains include those of the dipnoan Ceratodus, the actinopterygian Saurichthys, the temnospondyl Parotosuchus, and the dicynodonts Rechnisaurus and Wadiasaurus.

Classification

It was originally described as a prestosuchid, but Brusatte et al. (2010) found it to be a poposauroid in a detailed cladistic analysis.[4]

References

  1. ^ Bandyopadhyay, S. and Sengupta, D. P. (1999). Middle Triassic vertebrate faunas from India. Journal of African Earth Sciences 29: 233–241.
  2. ^ a b c Sen K. (2005). A new rauisuchian archosaur from the Middle Triassic of India. Palaeontology 48 (1): 185-196.
  3. ^ Sen, K. (2003). Pamelaria dolichotrachela, a new prolacertid reptile from the Middle Triassic of India. Journal of Asian Earth Sciences 21: 663–681.
  4. ^ Brusatte, S.L.; Benton, M.J.; Desojo, J.B.; and Langer, M.C. (2010). "The higher-level phylogeny of Archosauria (Tetrapoda: Diapsida)". Journal of Systematic Palaeontology 8 (1): 3–47. doi:10.1080/14772010903537732. http://www.informaworld.com/smpp/section?content=a919837956&fulltext=713240928. 

External links