240-Million-Year-Old Amphibian Fossil Discovered in Retaining Wall
Researchers from the University of New South Wales (UNSW Sydney) and the Australian Museum have formally named and described a 240-million-year-old amphibian fossil that was found in a retaining wall. The fossil, named Arenaerpeton supinatus meaning ‘supine sand creeper’, was discovered in rocks from a local quarry that were intended for the construction of a garden wall.
The fossil was initially found by a retired chicken farmer and was subsequently donated to the Australian Museum in Sydney. Palaeontologist Lachlan Hart, a PhD candidate at UNSW, stated that the fossil is a rare example of a temnospondyl, an extinct group of animals that lived before and during the time of the dinosaurs. The fossil not only preserves nearly the entire skeleton but also the outlines of its skin.
Arenaerpeton supinatus existed in what is now known as the Sydney Basin during the Triassic period. It likely inhabited freshwater rivers and preyed on other ancient fish. Interestingly, the fossil shares many similarities with the modern Chinese Giant Salamander, particularly in terms of its head shape. However, it was much larger and heavier than its living relatives, with notable teeth including fang-like tusks on the roof of its mouth.
What makes this discovery significant is the large size of Arenaerpeton supinatus. While closely related animals at the time were small, this amphibian was estimated to be about 1.2 meters long from head to tail. Dr. Matthew McCurry, Senior Lecturer at UNSW and Curator of Palaeontology at the Australian Museum, emphasized the importance of the fossil in Australian paleo history.
The findings, published in the Journal of Vertebrate Paleontology, shed light on the evolution and existence of temnospondyls across different geological periods. Later this year, the fossil will be on public display at the Australian Museum in Sydney, allowing visitors to marvel at this remarkable piece of Australia’s fossil heritage.
Reference: “A new chigutisaurid (Brachyopoidea, Temnospondyli) with soft tissue preservation from the Triassic Sydney Basin, New South Wales, Australia” by Lachlan J. Hart, Bryan M. Gee, Patrick M. Smith and Matthew R. McCurry, 3 August 2023, Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2023.2232829