Tag Archives: Isla Española

Naesiotus achatellinus Forbes

Achatinella-like Galapagos Snail (Naesiotus achatellinus)

The Achatinella-like Galapagos Snail was described in 1850.

There is no doubt that N. achatellinus is one of the rarer Galápagos land snails. It is of special interest because of its superficial resemblance to certain species of Hawaiian tree snails of the genus Achatinella. Also, its straight-sided, conical shape, its non-impressed, nodulose sutures, and its relatively bright color pattern set it apart from any other known species of Naesiotus from the Galápagos Islands or from the South American mainland.” [2]

The species was found first on Island San Cristóbal in the early 1830s and in 1846; in 1868, it was apparently also found on Isla Española.

The shells reach sizes of about 1,2 to 1,6 cm in height, they are: “perforated, ovate-pyramidal with long, conic spire, rather thin; variously colored, being banded with chestnut on an olivaceous or whitish ground, or chestnut below, white above, always with a white line below the suture; surface smooth and glossy, like an Achatinella with slight growth-wrinkles and an impressed band below the suture, pinched up into tubercles at irregular intervals.” [1]

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The Achatinella-like Galapagos Snail disappeared from Isla Española at an unknown date and was last seen on Isla San Cristóbal in the 1980s; it is now most likely extinct.

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References: 

[1] George W. Tryon; Henry A. Pilsbry; a.o.: Manual of Conchology. Second series: Pulmonata. Vol 11: American Bulimulidae: Bulimulus, Neopetraeus, Oxychona, and South American Drymaeus. 1897-1898
[2] Allyn G. Smith: New record for a rare Galápagos land snail. Nautilus 85(1): 5-8. 1971

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Depiction from: ‘George W. Tryon; Henry A. Pilsbry; a.o.: Manual of Conchology. Second series: Pulmonata. Vol 11: American Bulimulidae: Bulimulus, Neopetraeus, Oxychona, and South American Drymaeus. 1897-1898’

(public domain)

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edited: 01.06.2021