Caseolus Baixoensis
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The IUCN Red List of Threatened Species™ ISSN 2307-8235 (online) IUCN 2008: T157116A5039004 Caseolus baixoensis Assessment by: Seddon, M.B. View on www.iucnredlist.org Citation: Seddon, M.B. 2013. Caseolus baixoensis. The IUCN Red List of Threatened Species 2013: e.T157116A5039004. http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T157116A5039004.en Copyright: © 2015 International Union for Conservation of Nature and Natural Resources Reproduction of this publication for educational or other non-commercial purposes is authorized without prior written permission from the copyright holder provided the source is fully acknowledged. Reproduction of this publication for resale, reposting or other commercial purposes is prohibited without prior written permission from the copyright holder. For further details see Terms of Use. The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership. The IUCN Red List Partners are: BirdLife International; Botanic Gardens Conservation International; Conservation International; Microsoft; NatureServe; Royal Botanic Gardens, Kew; Sapienza University of Rome; Texas A&M University; Wildscreen; and Zoological Society of London. If you see any errors or have any questions or suggestions on what is shown in this document, please provide us with feedback so that we can correct or extend the information provided. THE IUCN RED LIST OF THREATENED SPECIES™ Taxonomy Kingdom Phylum Class Order Family Animalia Mollusca Gastropoda Stylommatophora Hygromiidae Taxon Name: Caseolus baixoensis Walden, 1983 Taxonomic Notes: Walden (1983) recognized a varietal name used by Wollaston, Caseolus commixtus var. pusilla, as meriting specific status, giving it the name baixoensis. Seddon (2008) reports difficulty separating Caseolus baixoensis Walden, 1983 and Caseolus compactus vigiae Walden, 1983, and in the absence of type material of the latter considered that these may be conspecific. Assessment Information Red List Category & Criteria: Vulnerable D2 ver 3.1 Year Published: 2013 Date Assessed: September 20, 2010 Justification: The species meets the range restriction criteria for Vulnerable B, one confirmed location and possible impact due to recreational use. Seddon (2008) suggested Data Deficient due to taxonomic uncertainties, however due to the precautionary principle a suggested listing of Vulnerable (VU) D2 is proposed, for the single known site. Recommended conservation actions include management of the protected areas for maintenance of this species and monitoring of the protected areas to ensure no loss of further habitat and subpopulations as well as more taxonomic research on the status of the species. Geographic Range Range Description: This species is endemic to Madeiran islands; it is only known from Porto Santo, where its complete range is uncertain, although there are reported records the South-East hills behind the harbour (Seddon 2008). Country Occurrence: Native: Portugal (Madeira) © The IUCN Red List of Threatened Species: Caseolus baixoensis – published in 2013. 1 http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T157116A5039004.en Distribution Map © The IUCN Red List of Threatened Species: Caseolus baixoensis – published in 2013. 2 http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T157116A5039004.en Population There are few specimens known for this species and hence the status is uncertain. Current Population Trend: Unknown Habitat and Ecology (see Appendix for additional information) The single known site is grassland with rocky areas. Systems: Terrestrial Use and Trade The species is not known to be utilised, although occasionally sold by shell collectors. Threats (see Appendix for additional information) The main threat is changing land management, for example overgrazing by livestock, and possible impact from recreational activities (creation of footpaths along coastal ridge). Conservation Actions (see Appendix for additional information) Recommended conservation actions include management of the protected areas for maintenance of this species and monitoring of the protected areas to ensure no loss of further habitat and subpopulations as well as more taxonomic research on the status of the species. Credits Assessor(s): Seddon, M.B. Reviewer(s): Groh, K., Cameron, R., Cuttelod, A. & Neubert, E. Contributor(s): Abreu, C., Cameron, R., Groh, K. & Teixeira, D. © The IUCN Red List of Threatened Species: Caseolus baixoensis – published in 2013. 3 http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T157116A5039004.en Bibliography Cameron, R.A.D., Cook, L.M. and Gao, G. 1996. Variation in snail species widespread on Porto Santo, Madeiran archipelago. Journal of Molluscan Studies 62(2): 143-150. IUCN. 2011. IUCN Red List of Threatened Species (ver. 2011.1). Available at: http://www.iucnredlist.org. (Accessed: 16 June 2011). Seddon, M.B. 2008. An illustrated compendium ofthe landsnails and slugs of the Madeiran archipelago. Studies in Biodiversity and Systematics of Terrestrial Organisms from the National Museum of Wales. Biotir Reports. Walden, H.W. 1983. Systematic and biogeographical studies of the terrestrial Gastropoda of Madeira. With an annotated Check-list. Annales Zoologica Fennica 20: 255-275. Citation Seddon, M.B. 2013. Caseolus baixoensis. The IUCN Red List of Threatened Species 2013: e.T157116A5039004. http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T157116A5039004.en Disclaimer To make use of this information, please check the Terms of Use. External Resources For Images and External Links to Additional Information, please see the Red List website. © The IUCN Red List of Threatened Species: Caseolus baixoensis – published in 2013. 4 http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T157116A5039004.en Appendix Habitats (http://www.iucnredlist.org/technical-documents/classification-schemes) Major Season Suitability Habitat Importance? 4. Grassland -> 4.4. Grassland - Temperate - Suitable Yes Threats (http://www.iucnredlist.org/technical-documents/classification-schemes) Threat Timing Scope Severity Impact Score 2. Agriculture & aquaculture -> 2.3. Livestock farming Ongoing Minority (50%) Causing/could Low impact: 5 & ranching -> 2.3.2. Small-holder grazing, ranching or cause fluctuations farming Stresses: 1. Ecosystem stresses -> 1.2. Ecosystem degradation 2. Species Stresses -> 2.2. Species disturbance 6. Human intrusions & disturbance -> 6.1. Ongoing - - - Recreational activities Stresses: 1. Ecosystem stresses -> 1.2. Ecosystem degradation Conservation Actions Needed (http://www.iucnredlist.org/technical-documents/classification-schemes) Conservation Actions Needed 2. Land/water management -> 2.1. Site/area management Research Needed (http://www.iucnredlist.org/technical-documents/classification-schemes) Research Needed 1. Research -> 1.1. Taxonomy 3. Monitoring -> 3.1. Population trends 3. Monitoring -> 3.4. Habitat trends Additional Data Fields Distribution Estimated area of occupancy (AOO) (km²): 4 Number of Locations: 1 © The IUCN Red List of Threatened Species: Caseolus baixoensis – published in 2013. 5 http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T157116A5039004.en The IUCN Red List of Threatened Species™ ISSN 2307-8235 (online) IUCN 2008: T157116A5039004 The IUCN Red List Partnership The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership. The IUCN Red List Partners are: BirdLife International; Botanic Gardens Conservation International; Conservation International; Microsoft; NatureServe; Royal Botanic Gardens, Kew; Sapienza University of Rome; Texas A&M University; Wildscreen; and Zoological Society of London. THE IUCN RED LIST OF THREATENED SPECIES™ © The IUCN Red List of Threatened Species: Caseolus baixoensis – published in 2013. 6 http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T157116A5039004.en.