Rhachistia aldabrae Martens, 1898
Aldabra banded snail
Taxonomy & Nomenclature
Synonym/s: Rachistia aldabrae Martens, 1898 [orth. error used by Régnier et al., 2009]
Conservation Status
Last record: 1997 (Gerlach, 2007)
Rediscovered on: 23 August 2014 (Battarbee, 2014)
IUCN RedList status: Extinct
The reported decline and subsequent disappearance of the species has been reported to be due to climate change (Gerlach, 2007). But the declaration of the species' extinction was viewed as premature by some (Hambler et al., 2007), and it was subsequently rediscovered (Battarbee, 2014). A new preprint also questions the cause of the species original decline (Altaba, 2022).
Table 1. Conservation status (historically).
| Year | Status | Notes | Reference |
| 2007 | Extinct | Due to climate change | Gerlach, 2007 |
| 2009 | Extinct | Source: Gerlach, 2007 | Régnier et al., 2009 |
| 2014 | Extant; rediscovered | Battarbee, 2014 | |
| 2017 | Extant | Cowie et al., 2017 |
Distribution
Aldabra Atoll, Seychelles
Biology & Ecology
Hypodigm
Media
References
Altaba, Cristian R. (2022). Extinction through Climate Change: Review of Evidence and Analysis of Two Land Snails from the Seychelles Islands. Preprints 2022100315 (https://doi.org/10.20944/preprints202210.0315.v1).
Battarbee, Richard W. (2014). The rediscovery of the Aldabra banded snail, Rhachistia aldabrae. Biology Letters 10: 20140771. https://doi.org/10.1098/rsbl.2014.0771
Commentary by Rhett A. Butler, mongabay.com (August 12, 2007). Climate change claims a snail. http://news.mongabay.com/2007/0813-snail.html
Cowie, Robert H., Régnier, Claire, Fontaine, Benoît, and Bouchet, Philippe. (2017). Measuring the Sixth Extinction: what do mollusks tell us? The Nautilus 131(1): 3-41.
Fisher, Diana O. and Humphreys, Aelys M. (2024). Evidence for modern extinction in plants and animals. Biological Conservation 298: 110772. https://doi.org/10.1016/j.biocon.2024.110772
Fryer, J. C. F. (1911). The structure and formation of Aldabra and neighbouring islands—with notes on their flora and fauna. Trans. Linn. Soc. Lond. Ser. 2: Zool 14: 401-442.
Gerlach, Justin. (2006). Terrestrial and freshwater Mollusca of the Seychelles Islands. Leiden, The Netherlands: Backhuys Publishers.
Gerlach, Justin. (2007). Short-term climate change and the extinction of the snail Rachistia aldabrae (Gastropoda: Pulmonata). Biology Letters 3: 581-585.
Gerlach, Justin. (2009). Rhachistia aldabrae. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. (http://www.iucnredlist.org). Downloaded on 01 June 2013.
Gerlach, Justin. (2012). Red Listing reveals the true state of biodiversity: a comprehensive assessment of Seychelles biodiversity. Phelsuma 20: 9-22.
Hambler, Clive et al. (2007). “Extinction” of Rhachistia aldabrae contested. Unpublished manuscript. [automatic download]
Holmes, Branden. (2021). What's Lost and What Remains: The Sixth Extinction in 100 Accounts (eBook). Self published.
Régnier, Claire, Fontaine, Benoît and Bouchet, Philippe. (2009). Not Knowing, Not Recording, Not Listing: Numerous Unnoticed Mollusk Extinctions. Conservation Biology 23(5): 1214-1221.
Thompson, C. J., S. Kodikara, M. A. Burgman, H. Demirhan, and L. Stone. 2020. Using survival theory models to quantify extinctions. Biological Conservation 241.
http://www.seychellesnewsagency.com/articles/1256/Living+to+fight+another+day++extinct+Aldabra+snail+re-discovered+in+Seychelles
http://www.seychellesnewsagency.com/articles/8818/+snails+endemic+to+Seychelles?disable_mobile=true