Concave Hirasea Snail (Hirasea biconcava)
This species was described in 1907, it was restricted to the island of Hahajima in the Ogasawara Islands, Japan.
The shells reach a height of about 0,2 cm and are about 0,4 cm in diameter.
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This species is also treated as subspecies of the Plane Hirasea Snail (Hirasea planulata Pilsbry & Hirase) .
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(public domain)
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edited: 11.05.2019