Sunday, September 23, 2012

[Paleontology • 2003] Chunerpeton tianyiensis • Earliest known crown-group salamanders from middle Jurassic, Inner Mongolia, China

Chunerpeton tianyiensis 
Gao and Chubin, 2003

Salamanders are a model system for studying the rates and patterns of the evolution of new anatomical structures. Recent discoveries of abundant Late Jurassic and Early Cretaceous salamanders are helping to address these issues. Here we report the discovery of well-preserved Middle Jurassic salamanders from China, which constitutes the earliest known record of crown-group urodeles (living salamanders and their closest relatives). The new specimens are from the volcanic deposits of the Jiulongshan Formation (Bathonian), Inner Mongolia, China, and represent basal members of the Cryptobranchidae, a family that includes the endangered Asian giant salamander (Andrias) and the North American hellbender (Cryptobranchus). These fossils document a Mesozoic record of the Cryptobranchidae, predating the previous record of the group by some 100 million years. This discovery provides evidence to support the hypothesis that the divergence of the Cryptobranchidae from the Hynobiidae had taken place in Asia before the Middle Jurassic period.

Amphibia Linnaeus, 1758
Lissamphibia Haeckel, 1866
Caudata Scopoli, 1777
Urodela Dumeril, 1806
Cryptobranchoidea Dunn, 1922
Cryptobranchidae Fitzinger, 1826
Chunerpeton tianyiensis gen. et sp. nov.

Gao, K. Q., and Shubin, N. H., 2003. Earliest known crown-group salamanders: Nature. 422. 424-428. doi:10.1038/nature01491.