Wayaosaurus

Last updated

Wayaosaurus
Temporal range: Carnian
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order:† Thalattosauria
Superfamily:† Askeptosauroidea
Genus:† Wayaosaurus
Zhou in Yin et al., 2000
Type species
† Wayaosaurus geei
Zhou in Yin et al., 2000
Other species
  • †Wayaosaurus bellus
    (Zhou in Yin et al., 2000)

Wayaosaurus is an extinct genus of thalattosaurian reptile that lived in what is now China. There are two species. The type species W. geei and the second species, W. bellus were both named by the same authors in 2000. [1]

Contents

Description and species

Wayaosaurus geei

W. geei was discovered near the town of Xinpu in Guanling County of the Guizhou Province of China. The place it was found corresponds to the Wayao Member of the Falang Formation, which dates to the Carnian Stage of the Late Triassic. The holotype, given the specimen number Gmr 004 has been lost since its original description in 2000, and the existing records of its apparent diagnostic traits are actually synapomorphies of Thalattosauria as a whole. Modern publications treat W. bellus as the only valid species. [2]

Wayaosaurus bellus

W. bellus was discovered in the same place as the undiagnostic type species. The holotype, originally named Gmr 003, but later redesignated GZDB 0005, consists of a partially complete skull with a mandible, most of the presacral vertebrae, pectoral girdle, all four limbs, and part of the pelvic girdle. It was given an emended diagnosis by Jun Chai and colleagues in 2023. Its autapomorphies include: a relatively short mandibular symphysis, a maximum transverse width of the skull in the temporal region, a moderate expansion at the distal end of the humerus, a well-developed inner trochanter on the femur, and a reduced deltopectoral crest. [2]

Classification

The classification of Thalattosauria has been controversial, and it is not known with confidence to which other reptiles they are closely related. They have been suggested to be relatives of Sauropterygia, Archosauromorpha, or possibly being part of a more primitive lineage. A cladogram summarizing the internal interrelationships of thalattosaurs, which was published by Chai and colleagues in their redescription of Wayaosaurus is shown below. [2]

Thalattosauria

References

  1. ↑ Yin GZ, Zhou XG, Cao ZT, Yu YT, Luo YM. 2000. A preliminary study on the early Late Triassic marine reptiles from Guanling, Guizhou, China. Geol Geol Chem. 28(3):1–22.
  2. 1 2 3 Chai, Jun; Lu, Hao; Jiang, Da-Yong; Motani, Ryosuke; Druckenmiller, Patrick S.; Tintori, Andrea; Kelley, Neil P. (2024). "Reidentification of Wayaosaurus bellus and the conservative trunk and tail shape of Thalattosauria". Historical Biology. 36 (12): 2537–2556. Bibcode:2024HBio...36.2537C. doi:10.1080/08912963.2023.2264886.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.