Partula clara 


Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Mollusca Gastropoda Stylommatophora Partulidae

Scientific Name: Partula clara
Species Authority: Pease, 1864
Common Name(s):
English Polynesian Tree Snail
Taxonomic Notes: Has always been considered a distinct species but DNA analysis suggests that it may be a colour morph of Partula hyalina and as such remains a candidate for merging. Populations in one valley are genetically distinct.

Assessment Information [top]

Red List Category & Criteria: Critically Endangered B2ab(ii,iv) ver 3.1
Year Published: 2009
Date Assessed: 2007-10-20
Assessor(s): Coote, T.
Reviewer(s): Cowie, R. & Seddon, M.B.
After the introduction of the carnivorous snail Euglandina rosea to Tahiti in 1977, populations and species of native partulid snails began to disappear rapidly as a result of predation. This species became rarer but very small isolated populations persisted and these were identified during the intensive surveys on the main island of Tahiti Nui 2003–2005 and on the peninsula of Tahiti Iti in 2007.
Previously published Red List assessments:
1996 Critically Endangered (CR)
1994 Extinct (Ex)

Geographic Range [top]

Range Description:This species is endemic to Tahiti, Society Islands. It is now restricted to only a few small populations in a few valleys around the island.
Countries occurrence:
French Polynesia (Society Is.)
Estimated area of occupancy (AOO) - km2:1-10
Continuing decline in area of occupancy (AOO):Yes
Extreme fluctuations in area of occupancy (AOO):No
Estimated extent of occurrence (EOO) - km2:
Number of Locations:30-40
Continuing decline in number of locations:Yes
Extreme fluctuations in the number of locations:No
Upper elevation limit (metres):300
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:Small subpopulations are scattered around Tahiti, mostly consisting of less than 50 individuals.
Current Population Trend:Decreasing
Additional data:
Extreme fluctuations:NoPopulation severely fragmented:Yes
Continuing decline in subpopulations:Yes
Extreme fluctuations in subpopulations:NoAll individuals in one subpopulation:No

Habitat and Ecology [top]

Habitat and Ecology:Habitat quality is not an issue for this species. Many populations survive in disturbed habitat, often not too far from human habitation.

Threats [top]

Major Threat(s): The principal threat to this species is Euglandina rosea but there is evidence that some populations have survived in spite of this introduced carnivorous species. The carnivorous flatworm Platydemus manokwari has been found in one area where P. clara persists but its imapct is unclear at the moment. The intrinsic problems associated with small population size also threaten the future of this species.

Conservation Actions [top]

Conservation Actions: This species is maintained in the international breeding programme. Some wild populations are regularly monitored.

Classifications [top]

1. Forest -> 1.6. Forest - Subtropical/Tropical Moist Lowland
suitability: Suitable  major importance:No
1. Forest -> 1.9. Forest - Subtropical/Tropical Moist Montane
suitability: Unknown  
3. Species management -> 3.3. Species re-introduction -> 3.3.1. Reintroduction
3. Species management -> 3.4. Ex-situ conservation -> 3.4.1. Captive breeding/artificial propagation
4. Education & awareness -> 4.3. Awareness & communications

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
In-Place Species Management
  Subject to ex-situ conservation:Yes
In-Place Education
8. Invasive & other problematic species & genes -> 8.1. Invasive non-native/alien species -> 8.1.2. Named species (Platydemus manokwari)
♦ timing: Ongoing ♦ scope: Unknown ♦ severity: Unknown ⇒ Impact score: Unknown 
→ Stresses
  • 2. Species Stresses -> 2.1. Species mortality

8. Invasive & other problematic species & genes -> 8.1. Invasive non-native/alien species -> 8.1.2. Named species (Euglandina rosea)
♦ timing: Ongoing ♦ scope: Whole (>90%) ♦ severity: Rapid Declines ⇒ Impact score: High Impact: 8 
→ Stresses
  • 2. Species Stresses -> 2.1. Species mortality

1. Research -> 1.2. Population size, distribution & trends
1. Research -> 1.5. Threats
3. Monitoring -> 3.1. Population trends

Bibliography [top]

Coote, T. 2007. Partulids on Tahiti: differential persistence of a minority of endemic taxa among relict populations. American Malacological Bulletin 22: 83-87.

IUCN. 2009. IUCN Red List of Threatened Species (ver. 2009.2). Available at: (Accessed: 3 November 2009).

Lee, T., Burch, J.B., Jung, Y., Coote, T., Pearce-Kelly, P. and Ó Foighil, D. 2007. Tahitian tree snail mitochondrial clades survived recent mass-extirpation. Current Biology 17(13): R502-R503.

Citation: Coote, T. 2009. Partula clara. In: The IUCN Red List of Threatened Species 2009: e.T16304A5599727. . Downloaded on 01 December 2015.
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