Japanese Fossils Reveal 3.5-Million-Year-Old Giant Salamander, Filling 60-Million-Year Record Gap
Updated
Updated · Sci.News · Jul 21
Japanese Fossils Reveal 3.5-Million-Year-Old Giant Salamander, Filling 60-Million-Year Record Gap
2 articles · Updated · Sci.News · Jul 21
Summary
Three vertebrae from Japan’s Kyushu Island have been reclassified as Limnospondylus ajimuensis, a new giant salamander genus and species that lived about 3.5 million years ago.
Micro-CT scans and geometric morphometric analysis showed the fossils—long assigned to the living genus Andrias—had a vertebral shape combination unseen in known cryptobranchids.
The animal may have reached about 1.1 meters and appears to have lived in freshwater lakes, unlike modern giant salamanders that mainly inhabit fast-flowing rivers.
That lake-dwelling lifestyle suggests extinct cryptobranchids occupied broader habitats, while cooling from about 2.6 million years ago and shrinking freshwater systems may have driven this lineage extinct.
The find helps fill East Asia’s sparse fossil record for a family more than 60 million years old and comes from Ajimu, the only known site with both giant salamander fossils and living genera.