Aaadonta constricta ssp. komakanensis
|Scientific Name:||Aaadonta constricta ssp. komakanensis Solem, 1976|
|Red List Category & Criteria:||Critically Endangered (Possibly Extinct) B1ab(i,ii,iii)+2ab(i,ii,iii) ver 3.1|
|Reviewer(s):||Barker, G., Seddon, M. & Pippard, H.|
This is a minute ground-dwelling snail for which no shells (live or dead) have been found in recent years, despite recent extensive surveys of its island habitat of Koror. The subspecies was previously known only from Koror, where it was collected at a single locality in 1936 by Y. Kondo. The species is listed as Critically Endangered (Possibly Extinct) due to a very small and declining extent of occurrence and area of occupancy, the species being found in a single location, and a decline in availability and quality of its habitat. Additional surveys of the island are needed to verify whether the subspecies is in fact Extinct, but based on extinctions of endodontids elsewhere in the Pacific, as well as other extirpations of endemic land snails on Koror, optimism is low.
This is a minute ground-dwelling snail that was historically known from the island of Koror (Oreor), where it was collected at a single locality in 1936 by Y. Kondo (Solem 1976). The historical geographic range was less than 20km2, and probably only approximately 7km2 (R. Rundell pers.comm. 2011). The species was probably historically more abundant prior to its collection at only a single locality in 1936.
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Aaadonta constricta komakanensis is a minute ground-dwelling snail for which no shells (live or dead) have been found in recent years, despite surveys of its island habitat of Oreor (“Koror”) in 2003, 2005 and 2007 (R.J. Rundell 2007 unpublished data; Rundell, 2005, 2010). The subspecies was previously known only from Oreor, where it was collected at a single locality in 1936 by Y. Kondo (Solem 1976: 478).|
|Current Population Trend:||Unknown|
|Habitat and Ecology:||This is a ground-dwelling snail recorded from moist lowland forest.|
|Continuing decline in area, extent and/or quality of habitat:||Yes|
|Use and Trade:||This species is not utilized.|
A. constricta komakanensis is (or was) 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).
|Conservation Actions:||This species is not protected. 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.|
|Citation:||Rundell, R.J. 2012. Aaadonta constricta ssp. komakanensis. The IUCN Red List of Threatened Species 2012: e.T198785A2534908.Downloaded on 24 September 2017.|