This species was described in 1986; it is known from subfossil shells that were found amongst a larger collection of shells in the Cueva de Kubler on the island of Santa Cruz in the Galápagos archipelago. [1]
The species was never seen alive and is clearly extinct.
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References:
[1] Steven M. Chambers; David W. Steadman: Holocene terrestrial gastropod faunas from Isla Santa Cruz and Isla Floreana, Galápagos: evidence for late Holocene declines. Transactions of the San Diego Society of Natural History 21(6): 89-110. 1986
This species was described in 1917, it was restricted to the Isla Santa Cruz in the Galápagos archipelago.
The species was last seen in 1974; it could not be found alive during the last recent searches and might thus be extinct.
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References:
[1] William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928
Darwin’s Galapagos Mouse was described in 1929; it was endemic to the Isla Santa Cruz in the Galápagos archipelago.
It reached lengths of about 22 cm, including the tail; it was predominantly cinnamon rufous colored, the upper parts with a mixture of blackish hairs, the tail was dusky above and whitish below. [1]
Darwin’s Galapagos Mouse was last seen in 1930; the species disappeared shortly after, perhaps due to the introduction of Norway Rats (Rattus norvegicus (Berkenhout)), Black Rats (Rattus rattus (L.)), and feral cats.
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References:
[1] Wilfred H. Osgood: A new rodent from the Galapagos Islands. Field Museum of Natural History 17(2): 21-24. 1929
The Indefatigable Island Snail was described in 1917, it is, or maybe was, endemic to Isla Santa Crus in the Galápagos Islands.
The species was found on tree trunks at 135 to 165 m elevation. [1]
The Indefatigable Island Snail was apparently not found during the most recent field searches and might be extinct.
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References:
[1] William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928
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Photo from: ‘’Abraham S. H. Breure: Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda) in the Royal Belgian Institute of Sciences, Brussels, with descriptions of two new species. ZooKeys 101: 1-50. 2011
Nils Odhner’s Galapagos Snail (Naesiotus sp. ‘nilsodhneri’)
Nils Odhner’s Galapagos Snail was described in 1985, its species epithet, however, is now considered a nomen nudum.
The species was restricted to the arid zones in the south-east of Isla Santa Cruz in the Galápagos archipelago; it was not found alive during the last recent field surveys and is now feared to be extinct.
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References:
[1] Guy Coppois: Etude de la spéciation chez les Bulimulidae endémiques de l’archipel des Galápagos (Mollusques, Gastéropodes, Pulmonés). Thèse de Doctorat, Libre de Bruxelles 1-283. 1985
Jose Villan’s Galapagos Snail (Naesiotus sp. ‘josevillani’)
Jose Villan’s Galapagos Snail was described in 1985, its species epithet, however, is now considered a nomen nudum, the reasons therefore are not known to me.
The species was endemic to the Isla Santa Cruz in the Galápagos archipelago, where it was found in the Scalesia forests of the higher altitudes. [1]
Jose Villan’s Galapagos Snail hasn’t been found during the most recent field searches and is thus considered very likely extinct.
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References:
[1] Guy Coppois: Etude de la spéciation chez les Bulimulidae endémiques de l’archipel des Galápagos (Mollusques, Gastéropodes, Pulmonés). Thèse de Doctorat, Libre de Bruxelles 1-283. 1985
De Ridder’s Galapagos Snail (Naesiotus sp. ‘deridderi’)
This species was described in 1985, its species epithet, however, is a nomen nudum.
De Ridder’s Galapagos Snail occurred in the moister regions of the island of Santa Cruz; the animals apparently had a certain preference for the Arrow-leaved Sida (Sida rhombifolia L.) or the Prickly Sida (Sida spinosa L.), on whose branches they were often found. [1]
The species was not found alive during the last recent field studies and is feared to be extinct.
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One of the few natural enemies of this species was the Woodpecker Finch (Camarhynchus pallidus (Sclater & Salvin)), which is known to occasionally pick up snails from the plants, which it subsequently beats against a twig or the like until the snail’s body detaches from the shell.
The reason for the extinction of so many of the endemic snail species of the Galápagos Islands, however, is mainly due to the destruction of their habitats.
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References:
[1] Guy Coppois: Etude de la spéciation chez les Bulimulidae endémiques de l’archipel des Galápagos (Mollusques, Gastéropodes, Pulmonés). Thèse de Doctorat, Libre de Bruxelles 1-283. 1985 [2] G. Coppois: Threatened Galapagos bulimulid land snails: an update. In: E. Alison Kay: The Conservation Biology of Molluscs. Occasional Paper of the IUCN Species Survival Commision 9: 8-11. 1995 [3] C. E. Parent; R. P. Smith: Galápagos bulimulids: status report on a devastated fauna. Tentacle 14. 2006 [4] C. E. Parent; B. J. Crepsi: Sequential colonization and diversification of Galapágos endemic land snail genus Bulimulus (Gastropoda, Stylommatophora). Evolution 60(11): 2311-2328. 2006
Blomberg’s Galapagos Snail was described in 1950 (or 1951 according to other sources) based on 12 specimens that were collected 200 to 300 m above sea level on plants, bushes and trees on the Isla Santa Cruz in the Galápagos archipelago. [1]
The species was apparently last seen alive in 1974; it was not found during the most recent field surveys and is feared to be extinct.
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References:
[1] Steven M. Chambers; David W. Steadman: Holocene terrestrial gastropod faunas from Isla Santa Cruz and Isla Floreana, Galápagos: evidence for late Holocene declines. Transactions of the San Diego Society of Natural History 21(6): 89-110. 1986
Adelphus’ Galapagos Snail, described in 1917, is endemic to the Isla Santa Cruz, Galápagos Islands, where it inhabited the island’s arid zones. [1]
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Robert P. Smith, a gastropod specialist, investigated the snail populations on six of the larger islands of the Galápagos archipelago in 1970, including Isla Santa Cruz. By 2005 and 2005, when exactly the same areas were investigated again, many populations had disappeared.
The touristic industry is booming on the islands, particularly on Isla Santa Cruz, and many of the former habitats are destroyed today, not only by development but also by the introduction of foreign species (animals and plants).
The highlands, formerly home to endemic species like the Galapagos Miconia (Miconia robinsoniana Cogn.) and the Santa Cruz Scalesia (Scalesia pedunculata Hook. F.) are now overrun by introduced plant species, just like the lower regions of the island are.
The snails are also killed by introduced ants, especially by the Little Fire Ant, also known as Electric Ant, (Wasmannia auropunctata (Roger)). [2][3]
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Adelphus’ Galapagos Snail was not found in recent years, despite specific searches, and is considered most likely extinct.
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References:
[1] William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928 [2] Christine E. Parent; Robert P. Smith: Galápagos bulimulids: status report on a devastated fauna. Tentacle 14. 2006 [3] Christine E. Parent; Bernard J. Crepsi: Sequential colonization and diversification of Galapágos endemic land snail genus Bulimulus (Gastropoda, Stylommatophora). Evolution 60(11): 2311-2328. 2006
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Photo from: ‘William Healey Dall; Washington Henry Ochsner: Landshells of the Galapagos Islands. Proceedings of the California Academy of Sciences. Ser. 4. Vol. 17.: 141-185. 1928’
