Species

BackLeiostyla arborea (Lowe, 1855)

Leiostyla arborea (Lowe, 1855)

  • Kingdom: Animalia
  • Phylum:
  • Class: Mollusca
  • Order: Gastropoda
  • Family: Lauriidae
VU Vulnerable
IUCN Red List Status:

Countries of Occurrence:
Portugal - Madeira

Archipelago(s):
Madeira

Assessor/s:
Seddon, M.B.

Reviewer/s:
Cameron, R., Groh, K., Cuttelod, A. & Neubert, E.

Contributor/s:
Cameron, R. & Teixeira, D.

Facilitators / Compilers/s:


Assessment Rationale:

Seddon (2008) suggested that this species should be considered as Near Threatened (version 3.1), as it is close to meeting the threshold for Endangered (EN) B2ab(iii) (version 3.1). This species is very localised, being present in two main areas on Madeira, representing four locations. The extent of occurrence is under 500 km², however the quality of habitat was not known to have declined in the last 15 years and one of the areas is protected by Natural Park status. Recent changes in 2010 on Madeira may have impacted this species, as there were extensive fires in central Madeira and major storms. As a consequence Cameron (pers. comm. 2010) considered that the species should be assessed as Vulnerable D2, given that the species requires large trees and is rarely found on young trees. He argues that these large trees are more vulnerable to storm damage and fires, and give the recent flood, storms and fires on Madeira, the species should be considered a higher risk. The agreed assessment was Vulnerable D2.

Geographic Range:

This species is endemic to the Madeiran islands, it is only found on the summit areas of central Madeira on the north side in the laurisilva zone and towards the northcentral coast., where it has an estimated area of occupancy of under 70 km², and at least  six different valleys.

Regions:
Portugal - Madeira
Extent of Occurrence (EOO):
(km2)
Area of Occupancy (AOO):
70 (km2)
Elevation Lower Limit:
(m)
Elevation Upper Limit:
(m)
Biogeographic Realms:
Palearctic
Presence:
Extant
Origin:
Endemic Madeira
Seasonality:
Resident

Population:

There are no recent data on population trend.

Habitat and Ecology

This species is found on the trunks of laurisilva trees, in moss and under bark (Seddon 2008).

Major Threat(s):

Cameron (pers. comm. 2010) notes that that the species requires large trees and is rarely found on young trees. He argues that these large trees are more vulnerable to storm damage and fires, and give the recent flood, storms and fires on Madeira, the species should be considered at higher risk. Any changes to the laurisilva zone which changes the numbers of large trees, such as logging, tourist developments, might impact the species.

Conservation Actions

Further survey work are required to determine the impact of the recent forest fires in August 2010 and the major storms in February 2010.