Aaadonta constricta ssp. babelthuapihttp://dx.doi.org/10.2305/IUCN.UK.2012.RLTS.T198783A2534750.en
|Scientific Name:||Aaadonta constricta ssp. babelthuapi|
|Species Authority:||Solem, 1976|
|Red List Category & Criteria:||Critically Endangered B1ab(i,ii,iii)+2ab(i,ii,iii) ver 3.1|
|Reviewer(s):||Seddon, M., Pippard, H. & Barker, G.|
This subspecies was previously known from a single locality on Babeldaob in Palau (where it is no longer found, and a single locality on Ngemelis, where it is also no longer found. It was recently found at another location - Ngatpang State on Babeldoab- in 2003. The species is given an assessment of Critically Endangered. The subspecies is found in a very small area, and from only one location. It is experiencing declines in habitat quality and extent. This is of particular concern, given the fragility of endodontid populations elsewhere in the Pacific, and the imminent threat of development activities on Babeldaob.
Aaadonta constricta babelthuapi is a minute ground-dwelling snail. This subspecies was previously known from a single locality on Babeldaob (where it is no longer found: Rundell 2005; R.J. Rundell, 2005, unpublished data) and a single locality on Ngemelis, where it is also no longer found (R.J. Rundell, 2005, unpublished data). The historical geographic range of this sub-species is estimated at 10km2. The area of occupancy for this subspecies is now estimated to be 1km2, and very few specimens were found recently at few localities in native forest in another part of Babeldoab - Ngatpang State - in 2003
|Estimated area of occupancy (AOO) - km2:||1|
|Continuing decline in area of occupancy (AOO):||Yes|
|Estimated extent of occurrence (EOO) - km2:||10|
|Continuing decline in extent of occurrence (EOO):||Yes|
|Lower elevation limit (metres):||1|
|Upper elevation limit (metres):||200|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||This species is no longer known from the single Babeldaob locality, nor Ngemelis, where the species was earlier reported (Rundell 2005, R.J. Rundell, 2005, unpublished data). However, three live shells were found in Ngatpang State on Babeldoab in 2003 (Rundell 2005, R.J. Rundell, 2003, unpublished data).|
|Current Population Trend:||Unknown|
|Habitat and Ecology:||This is a ground dwelling snail found in moist lowland forest.|
|Continuing decline in area, extent and/or quality of habitat:||Yes|
|Use and Trade:||This species is not utilized.|
A. constricta babelthuapi is threatened by destruction or modification of native lowland forest. Disruption of the ground, rocks and leaf litter may be of particular significance to this and other endodontid species. These threats are imminent, since the type locality for the species is on the island of Babeldaob, which is currently undergoing significant change due in part to the completion of the paved Compact Road around the island, which is facilitating development of previously remote locations. Endodontoid land snails are among the most threatened land snails on Pacific Islands in the few places where they still exist (Solem 1983).
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.
Colin, PL. 2009. Marine Environments of Palau. Indo-Pacific Press, San Diego.
Cowie, RH, Allison, A, Howarth, FG, Samuelson, GA, Evenhuis, NL. 1996. Impacts of the Palau Compact Road: Survey of the non-marine fauna of the Island of Babeldaob. Will Chee Planning, Honolulu.
Crombie, R.I. and Pregill, G.K. 1999. A checklist of the herpetofauna of the Palau Islands (Republic of Belau), Oceania. Herpetological Monographs 13: 29-80.
Hinz, E. 1995. Pacific Island Battlegrounds of World War II: Then and Now. The Bess Press, Honolulu.
IUCN. 2012. IUCN Red List of Threatened Species (ver. 2012.2). Available at: http://www.iucnredlist.org. (Accessed: 17 October 2012).
Motteler, LS. 2006. Pacific Island Names. Bishop Museum Press, Honolulu.
Rundell, RJ. 2005. The land snails of Belau: Survey of the 16 states.
Rundell, RJ. 2008. Cryptic diversity, molecular phylogeny and biogeography of the rock- and leaf litter-dwelling land snails of Belau (Republic of Palau, Oceania). Philosophical Transactions of the Royal Society of London B 363: 3401-3412.
Rundell, RJ. 2010. Diversity and conservation of the land snail fauna of the western Pacific islands of Belau (Republic of Palau, Oceania). American Malacological Bulletin 28: 81-90.
Smith, B.D. 1993. Working list of the terrestrial gastropods of Palau, Caroline Islands. Working List No. 4. Dickinson Memorial Mollusc Collection, Marine Laboratory, University of Guam.
Solem, A. 1976. Endodontoid land snails from Pacific islands (Mollusca: Pulmonata: Sigmurethra). Part I. Family Endodontidae. Field Museum of Natural History, Chicago.
Solem, A. 1983. Endodontoid land snails from Pacific islands (Mollusca: Pulmonata: Sigmurethra). Part II. Families Punctidae and Charopidae. Zoogeography. Field Museum of Natural History, Chicago.
|Citation:||Rundell, R.J. 2012. Aaadonta constricta ssp. babelthuapi. The IUCN Red List of Threatened Species 2012: e.T198783A2534750. http://dx.doi.org/10.2305/IUCN.UK.2012.RLTS.T198783A2534750.en . Downloaded on 14 October 2015.|
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