Aaadonta fuscozonata ssp. fuscozonata
| Kingdom |
Phylum |
Class |
Order |
Family |
| ANIMALIA |
MOLLUSCA |
GASTROPODA |
STYLOMMATOPHORA |
ENDODONTIDAE |
| Scientific Name: |
Aaadonta fuscozonata ssp. fuscozonata
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| Species Authority: |
(Beddome, 1889) |
Assessment Information
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| Red List Category & Criteria: |
Critically Endangered
D
ver 3.1
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| Year Published: |
2012 |
| Assessor/s: |
Rundell, R.J. |
| Reviewer/s: |
Seddon, M., Barker, G. & Pippard, H. |
| Contributor/s: |
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Justification:
The subspecies was previously known only from Koror, where it was collected at a single locality in 1936 by Y. Kondo. In recent surveys, only nine live specimens have been found, from four distinct and tiny Rock Islands (four localities). The subspecies is listed as Critically Endangered, based on the limited area of occupancy (approximately 2km2) and the very small number of specimens that have been found recently, despite surveys of available native habitat. The species is also found in areas where habitat quality and quantity is in decline. Site protection is recommended, as are surveys to determine the current distribution of this species and population size, status and trends.
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Geographic Range
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| Range Description: |
This is a minute ground-dwelling snail historically known from the island of Koror (Oreor) in Palau. Its historical geographic range is estimated at 7km2 based on occupancy of a small area of Koror. The species was probably historically more abundant prior to its collection at only a single locality in 1936. In recent surveys (Rundell 2010), the subspecies was found in very small areas on very small islands, and its current area of occupancy is estimated as 2km2.
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| Countries: |
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| Range Map: |
Click here to open the map viewer and explore range. |
Population
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| Population: |
Only few live shells (nine) were found in 2007 (R.J. Rundell 2007, unpublished data) on four northern Rock Islands in four localities on those islands. However, no specimens were found on the island from which the subspecies was described (Koror) in 2003, 2005 or 2007 surveys (R.J. Rundell 2007 unpublished data, Rundell 2005 and 2010).
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| Population Trend: |
Unknown
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Habitat and Ecology
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| Habitat and Ecology: |
This is a ground dwelling snail found in moist lowland forest.
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| Systems: |
Terrestrial |
| Major Threat(s): |
A. fuscozonata fuscozonata is threatened by destruction and modification of native lowland forest. Therefore it is not surprising that the species has probably been extirpated from the highly modified and deforested island of Koror. Disruption of the ground, rocks and leaf litter may be of particular significance to this and other endodontid species. Endodontoid land snails are among the most threatened land snails on Pacific Islands in the few places where they still exist (Solem 1983).
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Conservation Actions
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| Conservation Actions: |
Field work to define the current distribution of this species, as well as research on its population status and trends, is required. Identification of priority sites for species conservation (e.g. key biodiversity areas that include threatened land snails) and reducing the impacts of human activities, especially on the small islands, is also urgently needed. The Palau Conservation Society has been supportive of recent land snail survey work in Palau.
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