Chilean researchers have discovered fossils of frogs and toads dating back over 70 million years that are almost identical to species of frogs and toads found in nature today.
Frogs and toads survived the mass extinction that wiped out the dinosaurs they shared the earth with.
Felipe Suazo, researcher at the University of Chile, identified specimens belonging to the family Calyptocephalellidae (toads) and the genus Kuruleufenia (frogs) in Chilean Patagonia.
These toads and frogs coexisted with sauropods, hadrosaurs and other dinosaurs.
The study of researchers, published in the journal Cretaceous Research, confirms that both species survived the mass extinction event 66 million years ago widely believed to have wiped out dinosaurs.
Their ancestors, including the helmeted water toad, also known as the Chilean helmeted bull frog (Calyptocephalella gayi), are with us today.
“It is not clear why they were successful in surviving and proliferating during the Cenozoic, the era that continues until the Mesozoic,” Suazo said.
The fossils were discovered in the Rio de las Chinas valley in the southern province of Ultima Esperanza during paleontological surveys carried out in 2017 and 2018, the results of which were recently revealed.
The study was carried out in collaboration with Raul Gomez, a researcher at the University of Buenos Aires, who recorded similar fossils in Argentine Patagonia.
Suazo said the frogs live in freshwater habitats and that Chilean Patagonia is the southernmost place where the genus Kuruleufenia has been found.
The fossils date back to between 75 and 71 million years ago, when the region’s climate was very rainy and summer temperatures were mild.
“The morphology of these fossils is almost identical to that of the bones of the present-day Chilean helmeted bull frog (Calyptocephalella gayi), but it was decided for conservative reasons to attribute these fossils only at a family level, in waiting for new fossil remains that will allow us to corroborate whether or not they belong to the genus Calyptocephalella or to a new genus still unknown to science, ”said Suazo.
The fossils of Kuruleufenia are linked to the Surinamese common toad (Pipa pipa) and the African clawed frog (Xenopus laevis).
The helmeted water toad is listed as “vulnerable” on the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species due to human consumption, habitat loss, pollution , introduced species and the fungal disease chytridiomycosis.
Edited by Richard Pretorius and Kristen Butler