京都大学研究团队对日本大分县阿积木地区出土的化石进行重新分析，确认发现了一个巨型蝾螈属的新物种，命名为林沼椎蝾螈（Limnospondylus ajimuensis）[1]。这三块椎骨化石距今约350万年，来自上新世时期[1]。
该物种成年体长约1.1米，曾生活在温暖湿润的九州湖泊和沼泽地带[1]。研究首作者Masahiro Noda指出："阿积木地区是世界上唯一同时发现了巨型蝾螈科已灭绝属种和现存属种化石的地点"[1]。这一发现将已知巨型蝾螈科的属数从5个增加至6个[1]。随着气候冷却和栖息地环境变化，该物种最终走向灭绝[1]。
Researchers at Kyoto University have confirmed the discovery of a previously unknown giant salamander species based on fossil remains uncovered in Ajumu, Oita Prefecture, Japan. [1] The three vertebral bones—comprising anterior trunk, mid-trunk, and sacrocaudal vertebrae—have been identified as belonging to Limnospondylus ajimuensis, marking the sixth known genus within the giant salamander family. [1] The species, which lived approximately 3.5 million years ago during the Pliocene epoch, reached an adult length of roughly 1.1 meters and inhabited the warm, humid lakes and wetlands of Kyushu before going extinct due to climate cooling and habitat transformation. [1]
The findings were published on July 23, 2026, with Masahiro Noda as the lead researcher. [1] According to Noda, "Ajumu contains the only site in the world where fossils of the giant salamander family and extant genera have both been found," highlighting the site's unique paleontological significance. [1]