Mammal Fossil in Fukui Found to Be One of Oldest in Japan

Society

Fukui, Feb. 7 (Jiji Press)--A fossil found in a stratum dated to the Lower Cretaceous period some 127 million years ago in Ono, Fukui Prefecture, central Japan, has been confirmed to be one of the oldest mammal fossils in the country, the Fukui Prefectural Dinosaur Museum said Sunday.

The fossil is a part of the lower jawbone of a member of the eutriconodonta, an order of early mammals in the age of the dinosaurs. The early mammal is highly likely to be a new species, according to the museum.

The bone, discovered by a curator of the Ono municipal board of education in June 2019, is 13.1 millimeters in length and 5.8 millimeters in height. Three teeth are attached to it.

Two of the three teeth have projections that are characteristic of members of the eutriconodonta. The fossil is assumed to be that of a mouse-like mammal with an overall length of 16-17 centimeters.

Although additional materials would be necessary to determine the species of the mammal, the shape and the size of the teeth suggest that it may be a species that has never been found in Japan.

[Copyright The Jiji Press, Ltd.]

Jiji Press