Toyotamaphimeia (named after Toyotama-hime) is a genus of extinct gavialid crocodylian which lived in Japan and Taiwan during the Middle Pleistocene. A specimen recovered in 1964 at Osaka University during the construction of a new science building has been dated to around 430–380 thousand years old based on the stratum in which it was found. Toyotamaphimeia was a fairly large crocodylian measuring approximately long. Two species are named, T. machikanensis from Japan and T. taiwanicus from Taiwan, both originally described as members of the genus Tomistoma.
Toyotamaphimeia (named after Toyotama-hime) is a genus of extinct gavialid crocodylian which lived in Japan and Taiwan during the Middle Pleistocene. A specimen recovered in 1964 at Osaka University during the construction of a new science building has been dated to around 430–380 thousand years old based on the stratum in which it was found. Toyotamaphimeia was a fairly large crocodylian measuring approximately long. Two species are named, T. machikanensis from Japan and T. taiwanicus from Taiwan, both originally described as members of the genus Tomistoma.
==History and naming== thumb|left|alt=Holotype material of Toyotamaphimeia, Scalebar = 20cm|Known material of T. machikanensis The first bones belonging to Toyotamaphimeia were discovered on May 3, 1964, during the construction of a new school building on the grounds of Ôsaka University. A field survey was conducted shortly afterwards, confirming the presence of more fossils, however not yet identifying their crocodilian nature. Following the survey several digs were organized starting on 9 June 1964. The skull was found on September 17 during the second dig. A third excavation was held in December which yielded more material of Toyotamaphimeia as well as fossil shellfish, insects and plant remains. Finally a fourth excavation took place in January 1965. Following analysis of the fossils, the material was assigned to the genus Tomistoma and named Tomistoma machikanense. In 1983, 18 years after the initial discovery, the skull was redescribed and deemed different enough from Tomistoma to erect a new genus, Toyotamaphimeia creating the comb. nov. Toyotamaphimeia machikanensis. In turn, Aoki also changed the species name from machikanense to machikanensis, as the new genus name was feminine. Similar remains were also known from Taiwan and had been classified as Tomistoma taiwanicus and Toyotamaphimeia sp. respectively, the former of which suggested as a species of Toyotamaphimeia already in 1983. A 2023 study concluded that both belonged to a single taxon: the Taiwanese form retained the species name, but was placed in Toyotamaphimeia, creating the new combination T. taiwanicus.
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