Ogasawarana obtusa
Ogasawarana obtusa is an extinct species of snail from Chichi-jima, Ogasawara, Japan. The holotype and paratypes are from 720 years BP. The shell is  in diameter and  in height. It has approximately 3.5 whorls. The surface of the shell is smooth, with fine growth lines and no spiral lines. References

Endemic molluscs of Japan
Gastropods described in 2008