An illustration depicts Arenaerpeton supinatus, the prehistoric relative of the present-day Chinese Giant Salamander. Artwork credit: Jose Vitor Silva
The ancient amphibian Arenaerpeton supinatus was unearthed in stones extracted from a local quarry, originally destined for the construction of a garden wall.
Scientists from the University of New South Wales (UNSW Sydney) and the Australian Museum have named and thoroughly described a fossil of an amphibian dating back to 240 million years ago. It was discovered in a retaining wall in the 1990s, marking a significant discovery.
Originally found by a retired poultry farmer, the fossil was embedded in rocks from a nearby quarry that were meant for building a garden wall. Later, it was given to the Australian Museum in Sydney.
Arenaerpeton supinatus Explained
Lachlan Hart, a paleontologist connected with both UNSW Science and the Australian Museum, revealed that the fossil, named Arenaerpeton supinatus or ‘supine sand creeper’, presents nearly the entire skeleton, including an unusual preservation of its skin’s outlines.
Resembling the existing Chinese Giant Salamander, Arenaerpeton stands as a singular specimen of the extinct temnospondyls, creatures that roamed the earth before and during the age of the dinosaurs, according to Hart, who is also a PhD student at UNSW’s School of Biological, Earth and Environmental Sciences.
He emphasized the rarity of finding skeletons with both the head and body intact, along with preserved soft tissue.
Habitat and Physical Traits
The Sydney Basin was home to Arenaerpeton, where it resided in freshwater rivers during the Triassic era, some 240 million years ago. Mr. Hart suggested that it likely preyed on ancient fish such as Cleithrolepis. Little is known about the other creatures it may have coexisted with.
Superficially resembling the modern Chinese Giant Salamander in its head shape, Hart notes that the fossil reveals that it was considerably more robust than its contemporary descendants, with notably sharp teeth including two fang-like tusks.
Significance of the Find
The discovery’s excitement lies in Arenaerpeton’s large size, roughly 1.2 meters from head to tail, compared to other related animals of the same era. Hart reflects on the last temnospondyls in Australia, which appeared 120 million years after Arenaerpeton and grew to enormous sizes. This increase in size may have contributed to their enduring presence across two mass extinctions.
Dr. Matthew McCurry, Senior Lecturer at UNSW’s School of BEES and Curator of Palaeontology at the Australian Museum, acknowledged the fossil as a milestone in Australian paleontological history.
Highlighting the fossil as one of New South Wales’ most significant discoveries in the past three decades, Dr. McCurry expressed his excitement at formally presenting it, considering it a vital piece of Australia’s fossil legacy.
The recent study has been published in the Journal of Vertebrate Paleontology, and the fossil is set to be exhibited at the Australian Museum in Sydney later this year.
Reference: Publication in the Journal of Vertebrate Paleontology titled “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, dated 3 August 2023, DOI: 10.1080/02724634.2023.2232829.
