Map_thumbnail_large_font

Pachnodus silhouettanus 

Scope: Global
Language: English
Status_ne_offStatus_dd_offStatus_lc_offStatus_nt_onStatus_vu_offStatus_en_offStatus_cr_offStatus_ew_offStatus_ex_off

Translate page into:

Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Mollusca Gastropoda Stylommatophora Cerastidae

Scientific Name: Pachnodus silhouettanus Van Mol & Coppois, 1980
Taxonomic Notes: Endemic to Silhouette island, Seychelles.  Area of occupancy 15km2

Assessment Information [top]

Red List Category & Criteria: Near Threatened ver 3.1
Year Published: 2009
Date Assessed: 2006-01-11
Annotations:
Needs updating
Assessor(s): Gerlach, J.
Reviewer(s): Miller, R.M., Seddon, M.B. & Pollock, C.M.
Justification:
This species has a restricted range, with an estimated extent of occurrence and area of occupancy of 15 km². Within this area populations are stable, but are vulnerable to further habitat degradation. Wood plantations have caused habitat degradation in the past, and invasive species are impacting its habitat currently. The species is adaptable and is acitvely recolonizing abandoned coconut plantations, but is less tolerant of invasion by other plant species (especially Cinnamomum verum).

Geographic Range [top]

Range Description:An arboreal snail endemic to Silhouette island, Seychelles, this species has an estimated extent of occurrence (EOO) and area of occupancy (AOO) of 15 km².
Countries occurrence:
Native:
Seychelles (Seychelles (main island group))
Additional data:
Estimated area of occupancy (AOO) - km2:15Continuing decline in area of occupancy (AOO):No
Extreme fluctuations in area of occupancy (AOO):NoEstimated extent of occurrence (EOO) - km2:15
Continuing decline in extent of occurrence (EOO):NoExtreme fluctuations in extent of occurrence (EOO):No
Continuing decline in number of locations:No
Extreme fluctuations in the number of locations:No
Upper elevation limit (metres):400
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:In 2005, the population size was estimated to be 46,600. The population is currently increasing, as the species actively recolonizes abandoned coconut plantations.
Current Population Trend:Increasing
Additional data:
Number of mature individuals:46600Continuing decline of mature individuals:No
Extreme fluctuations:NoPopulation severely fragmented:No
Continuing decline in subpopulations:No
Extreme fluctuations in subpopulations:NoAll individuals in one subpopulation:No

Habitat and Ecology [top]

Habitat and Ecology:An arboreal species, this snail is found in lowland forest from sea level to 400 m. It is an adaptable species, capable of recolonizing abandoned coconut plantations, but is less tolerant of invasion by other plant species (especially Cinnamomum verum).
Systems:Terrestrial
Continuing decline in area, extent and/or quality of habitat:Yes

Threats [top]

Major Threat(s): This species is vulnerable to habitat degradation, which was caused in the past by both small- and large-scale wood plantations and is currently taking place due to the impacts of invasive alien plant species, such as Cinnamomum verum.

Conservation Actions [top]

Conservation Actions: There are no conservation measures in place for this snail. The forests on Silhouette island should be protected.

Citation: Gerlach, J. 2009. Pachnodus silhouettanus. The IUCN Red List of Threatened Species 2009: e.T168110A6451229. . Downloaded on 23 September 2017.
Disclaimer: To make use of this information, please check the <Terms of Use>.
Feedback: If you see any errors or have any questions or suggestions on what is shown on this page, please provide us with feedback so that we can correct or extend the information provided