Haratashino Formation
Miocene, Tomioka Group, Annaka-shi, Gunma Prefecture, Japan
ver. 2.3
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There is a localitiy on the riverbank of the Usui River running through Gunma Prefecture. This locality produces beautiful shark teeth such as Megalodon and hastalis. A lot of pretty small shark teeth were found at a narrow area, about several meters wide and ten meters in length of the river bank. Most of them were deep sea sharks. Squaloids were dominant among them and found to be consist of four genera. Etomopterus was the most abundunt species among them. The locality also yields a vareity of dermal denticles accompanied with shark teeth.

Deania calcea

Etmopterus spp.

Squaliolus schaubi

Centroscymnus sp.

Chlamydoselachus cfr.anguineus,


Dermal denticles

Dalatias licha

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ver. 2.3 20110428 (ver. 1.0 20000615 Tukahara F. )
Fumio Nakagawa