The discovery of Litoria tylerantiqua suggests that Australian treefrogs (pelodryadids) were present in Australia by the Early Eocene, when the continent was still connected to Antarctica and South America as the last remnants of the supercontinent Gondwana.
An artist’s reconstruction of Litoria tylerantiqua (right) and the previously-described species Platyplectrum casca (left) from Murgon, south-eastern Queensland. Image: Samantha Yabsley, https://www.instagram.com/s.h.y_art.
Litoria tylerantiqua lived in Australia during the Early Eocene epoch, approximately 55 million years ago.
The frog’s fossil bones were collected in the 1990s by University of New South Wales paleontologists by screen-washing clay samples from the Tingamarra fossil frog deposit in Murgon, Queensland.
“Around 55 million years ago, Australia, Antarctica and South America were linked together as the last remnants of Gondwana,” said Dr. Roy Farman, a researcher at the University of New South Wales and the Australian National University, and colleagues.
“Global climates were warmer during this period, while a forested corridor linked South America and Australia.”
“Up until now, it was thought the earliest Australian tree frogs came from the Late Oligocene (about 26 million years ago) and the Early Miocene (23 million years ago).”
“Fossils of the Late Oligocene were found at Kangaroo Well in the Northern Territory and Etadunna Formation at Lake Palankarinna, South Australia, while the Riversleigh World Heritage Area in Queensland revealed tree frogs from the Early Miocene.”
“But the new species extends the fossil record of pelodryadids by approximately 30 million years, to a time potentially close to the divergence of Australian tree frogs from the South American tree frogs,” they said.
“Previous estimates based on molecular clock studies suggested that Australian and South American tree frogs separated from each other at about 33 million years ago.”
Litoria tylerantiqua joins the only other Murgon frog, the ground-dwelling Platyplectrum casca (previously described as Lechriodus casca), as the oldest frogs known from Australia.
Both have living relatives in Australia and New Guinea demonstrating remarkable resilience over time.
“Despite their delicate nature, frogs have been surprisingly successful at surviving several mass extinction events since their origins about 250 million years ago, including the mass extinction 66 million years ago that took out the non-flying dinosaurs,” Dr. Farman said.
“Although global extinction events triggered by human activities — such as rapid climate change and the spread of chytrid fungus — may be among the worst challenges frogs have had to face, the fossil record could reveal how some frog groups overcame previous challenges, perhaps by adapting to new, less-threatening habitats.”
“This could provide clues about how we might be able to help by translocating some threatened frogs into more future-secure habitats.”
“Frogs such as the southern corroboree frog (Pseudophryne corroboree) are threatened in their current habitats which have become more hostile due to climate change.”
“If the fossil record shows physically similar frogs living in very different habitats, today’s frogs may benefit by being reintroduced into similar environments.”
The discovery is described in a paper in the Journal of Vertebrate Paleontology.
_____
Roy M. Farman et al. Early Eocene pelodryadid from the Tingamarra Local Fauna, Murgon, southeastern Queensland, Australia, and a new fossil calibration for molecular phylogenies of frogs. Journal of Vertebrate Paleontology, published online May 14, 2025; doi: 10.1080/02724634.2025.2477815
