The genus Calyptocephalella contains one living species, the
helmeted water toad (C. gayi), which is very large and mostly aquatic. The genus Telmatobufo contains four species, T. australis, T. bullocki, T. ignotus, and T. venustus.[1] All five living species within the family are considered threatened, with T. bullocki and T. venustus being classified as
critically endangered.[2]
The family has been present in southern South America since the Late
Cretaceous[3] and were present in the
Antarctic Peninsula during the
Eocene.[4] While originally widespread in
Patagonia east of the Andes, they later became extinct in this region after the Late
Miocene, likely due to increasingly cold and arid conditions.[5] A particularly large indeterminate fossil species is known from the Eocene of southern Chile.[6]
They are the
sister group to the superfamily
Myobatrachoidea, which inhabits
Australasia; the ancestors of Myobatrachoidea likely diverged from Calyptocephalellidae in South America, but migrated south to Australasia via then ice-free
Antarctica. Together, these groups comprise the clade
Australobatrachia.[7]
References
^Frost, Darrel R. (2013).
"Calyptocephalellidae, Reig 1960". Amphibian Species of the World 6.0, an Online Reference. American Museum of Natural History. Retrieved 19 September 2014.
^Agnolin, F. A new Calyptocephalellidae (Anura, Neobatrachia) from the Upper Cretaceous of Patagonia, Argentina, with comments on its systematic position. Stud. Geol. Salamanticensia 48, 129–178 (2012).
^Otero, R.A.; P. Jimenez-Huidobro; S. Soto-Acuña; R.E.Yury-Yáñez (2014). "Evidence of a giant helmeted frog (Australobatrachia, Calyptocephalellidae) from Eocene levels of the Magallanes Basin, southernmost Chile". Journal of South American Earth Sciences. 55: 133–140.
doi:
10.1016/j.jsames.2014.06.010.