The Straight Hirasea Snail was described in 1907; it is, or maybe was, restricted to the island of Hahajima in the Ogasawara Islands, Japan.

The shells reach sizes of about 0,2 cm in height and about 0,3 cm in diameter; the spire is low-conic and the base very convex.

The species is now likely extinct. [1]

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References:

[1] Robert H. Cowie; Claire Régnier; Benoît Fontaine; Philippe Bouchet. Measuring the Sixth Extinction: what do mollusks tell us? The Nautilus 131(1): 3-41. 2017

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Depiction from: ‘The Conchological Magazine 1907’

(public domain)

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edited: 17.05.2022