Shinisauria

Summary

Shinisauria is a clade or evolutionary grouping of anguimorph lizards that includes the living Chinese crocodile lizard Shinisaurus and several of its closest extinct relatives. Shinisauria was named in 2008 by Jack Lee Conrad as a stem-based taxon to include all anguimorphs more closely related to Shinisaurus than to Anguis fragilis, Heloderma suspectum or Varanus varius.[1] Several recent phylogenetic analyses of lizard evolutionary relationships place Shinisauria in a basal position within the clade Platynota, which also includes monitor lizards, helodermatids, and the extinct mosasaurs. Shinisaurians were once thought to be closely related to the genus Xenosaurus, but they are now considered distant relatives within Anguimorpha.[2] The fossil record of shinisaurians extends back to the Early Cretaceous with Dalinghosaurus, which is from the Aptian aged Yixian Formation of China.[1] Two other extinct shinisaurians are currently known: Bahndwivici from the Eocene of Wyoming and Merkurosaurus from the Late Oligocene of Germany and the Early Miocene of the Czech Republic.[3] An indeterminate shinisaurian is known from an isolated tail found in the Eocene aged Messel pit in Germany.[4]

Shinisauria
Temporal range: Early Cretaceous - present, 124.6–0 Ma
The Chinese crocodile lizard, the only living member of Shinisauria (Shinisaurus).
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Infraorder: Paleoanguimorpha
Clade: Shinisauria
Conrad, 2008
Subgroups

Dalinghosaurus
Merkurosaurus
Bahndwivici
Shinisaurus

Fossil of Dalinghosaurus longidigitus, the oldest known shinisaurian

References edit

  1. ^ a b Conrad, J. L. (2008). "Phylogeny and Systematics of Squamata (Reptilia) Based on Morphology" (PDF). Bulletin of the American Museum of Natural History. 310: 1–182. doi:10.1206/310.1. S2CID 85271610.
  2. ^ Conrad, J. L.; Ast, J. C.; Montanari, S.; Norell, M. A. (2011). "A combined evidence phylogenetic analysis of Anguimorpha (Reptilia: Squamata)". Cladistics. 27 (3): 230. doi:10.1111/j.1096-0031.2010.00330.x. S2CID 84301257.
  3. ^ Klembara, J. (2008). "A New Anguimorph Lizard from the Lower Miocene of North-West Bohemia, Czech Republic". Palaeontology. 51: 81–94. doi:10.1111/j.1475-4983.2007.00732.x.
  4. ^ Smith, Krister T. (2017-05-04). "First crocodile-tailed lizard (Squamata: Pan-Shinisaurus ) from the Paleogene of Europe". Journal of Vertebrate Paleontology. 37 (3): e1313743. doi:10.1080/02724634.2017.1313743. ISSN 0272-4634. S2CID 89730027.