The Keeled Wollastonia Snail is known exclusively from Quaternary deposits along the southeastern coast of Porto Santo, Madeiran Islands, Portugal.

The species was described in 1878, originally as a kind of subspecies or variety of another species, Wollastonia oxytropis (R. T. Lowe), of which it differs by its larger size beside some other features like a more distinctly marked suture, the finer granulation, and the wider aperture. [1]

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The Keeled Wollastonia Snail disappeared before the scientific exploration of Porto Santo in the 19th century, it probably died out due to changes in the microclimate of its habitat.

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References:

[1] Willy De Mattia; Marco T. Neiber; Klaus Groh: Revision of the genus-group Hystricella R. T. Lowe, 1855 from Porto Santo (Madeira Archipelago), with descriptions of new recent and fossil taxa (Gastropoda, Helicoidea, Geomitridae). ZooKeys 732: 1-125. 2018

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Photo from: ‘Willy De Mattia; Marco T. Neiber; Klaus Groh: Revision of the genus-group Hystricella R. T. Lowe, 1855 from Porto Santo (Madeira Archipelago), with descriptions of new recent and fossil taxa (Gastropoda, Helicoidea, Geometridae). ZooKeys 732: 1-125. 2018’

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edited: 01.08.2022