Chthonerpeton

Chthonerpeton
Chthonerpeton indistinctum
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Amphibia
Order:	Gymnophiona
Clade:	Apoda
Family:	Typhlonectidae
Genus:	Chthonerpeton Peters, 1880

Chthonerpeton is a genus of semiaquatic caecilian amphibians in the family Typhlonectidae. They occur in South America east of the Andes, with most species occurring along the Brazilian Atlantic coast. ^{[1] [2]}

With ten currently recognized species, Chthonerpeton is the most speciose genus within Typhlonectidae. ^[3] Species are characterized by having several diagnostic traits, including small ovate external nares, tentacular apertures located at an intermediate position between the eye and naris, and unroofed tentacular grooves. ^{[4] [5]}

Phylogenetically, Chthonerpeton is often recovered as the sister taxon to all other typhlonectids and retains plesiomorphic features, such as a subcylindrical body and the absence of fins. ^{[6] [7]}

Species

Chthonerpeton contains the following species: ^[1]

• Chthonerpeton arii Cascon and Lima-Verde, 1994
• Chthonerpeton braestrupi Taylor, 1968
• Chthonerpeton exile Nussbaum and Wilkinson, 1987
• Chthonerpeton indistinctum (Reinhardt and Lütken, 1862)
• Chthonerpeton markwilkinsoni Santos, Pineschi, and Zaher, 2025
• Chthonerpeton noctinectes Silva, Britto-Pereira, and Caramaschi, 2003
• Chthonerpeton onorei Nussbaum, 1986
• Chthonerpeton perissodus Nussbaum and Wilkinson, 1987
• Chthonerpeton tremembe Maciel, Leite, Silva-Leite, Leite, and Cascon, 2015
• Chthonerpeton viviparum Parker and Wettstein, 1929

References

1. Frost, Darrel R. (2017). "Chthonerpeton Peters, 1880". Amphibian Species of the World: an Online Reference. Version 6.0. American Museum of Natural History. Retrieved 29 June 2017.
2. Vitt, L. J.; Caldwell, J. P. (25 March 2013). Herpetology: An Introductory Biology of Amphibians and Reptiles. Academic Press. pp. 453–454. ISBN   978-0-12-386920-3. OCLC   898295183.
3. Santos, R.O.; Pineschi, R.B.; Zaher, H. (2025). A new species of Chthonerpeton (Amphibia: Gymnophiona: Typhlonectidae) from Rio de Janeiro, Brazil. Zootaxa 5728(3): 561–570. doi:10.11646/zootaxa.5728.3.6
4. Wilkinson, M. & Nussbaum, R.A. (2006). Caecilian phylogeny and classification. In: Exbrayat, J.-M. (ed.), Reproductive Biology and Phylogeny of Gymnophiona: Caecilians. CRC Press, pp. 39–78.
5. Wilkinson, M.; San Mauro, D.; Sherratt, E.; Gower, D.J. (2011). A nine-family classification of caecilians (Amphibia: Gymnophiona). Zootaxa 2874: 41–64.
6. Wilkinson, M.; Nussbaum, R.A. (1999). "Evolutionary relationships of the caecilian family Typhlonectidae (Amphibia: Gymnophiona)". Zoological Journal of the Linnean Society. 126: 191–223.
7. Maciel, A.O.; Sampaio, M.I.; Hoogmoed, M.S.; Schneider, H. (2017). Phylogenetic relationships of the largest lungless tetrapod (Gymnophiona, Atretochoana) and the evolution of lunglessness in caecilians. Zoologica Scripta 46(3): 255–263.