''Chunerpeton tianyiensis'' is an extinct

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

salamander Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All t ...

from the Late

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

Daohugou Beds The Haifanggou Formation (), also known as the Jiulongshan Formation (), is a fossil-bearing rock deposit located near Daohugou () village of Ningcheng County, in Inner Mongolia, northeastern China. The formation consists of coarse Conglomerate ( ...

in Ningcheng County, Nei Mongol (Inner Mongolia), China. It is the only species classified under the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Chunerpeton'', which means "early creeping animal". It was a small animal measuring 18 cm in length. It was neotenic, with the retention of external gills into adulthood. In the original description it was placed in Cryptobranchidae, which contains modern giant salamanders. A redescription published in 2020 found it to be a

stem-group In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. ...

caudatan outside the

crown group In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor ...

of modern salamanders. A 2021 study found it to be a member of

Cryptobranchoidea The Cryptobranchoidea are a suborder of salamanders found in Asia, European Russia, and the United States. They are known as primitive salamanders, in contrast to Salamandroidea, the advanced salamanders. It has two living subdivisions, Cryptobr ...

outside of Cryptobranchidae. In 2022 a more extensive analysis, with greater character and taxon sampling, recovered ''Chunerpeton tianyiense'' as a

caudatan, outside the

of modern salamanders, and associated with ''

Beiyanerpeton jianpingensis ''Beiyanerpeton'' is an extinct genus of salamandroid amphibians known from the Late Jurassic of western Liaoning Province, China. It contains a single species, ''B. jianpingensis''. Alternative analyses suggest that ''B. jianpingensis'' is a ste ...

'' and '' Qinglongtriton gangouensis''. ''Chunerpeton tianyiensis'' has been used to constrain the age of

in over a dozen molecular divergence analyses but given the uncertain affinity of the taxon perhaps it should no longer be used in this way. It lived with likely

salamanders, e.g. '' Jeholotriton paradoxus'' Wang 2000, '' Liaoxitriton daohugouensis'' Wang 2004, and '' Pangerpeton sinensis'' Wang & Evans 2006 of the same age.

References

Further reading