IUCN SSC Mid-Atlantic Island Invertebrates Specialist Group

Species

BackActinella actinophora R.T. Lowe, 1831)

Actinella actinophora R.T. Lowe, 1831)

  • Kingdom: Animalia
  • Phylum:
  • Class: Mollusca
  • Order: Gastropoda
  • Family: Hygromiidae
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:
Killeen, I.

Facilitators / Compilers/s:


Assessment Rationale:

This species is considered to be borderline between Vulnerable and Near Threatened, as it has a restricted range, the number of known locations is less than 10, but the habitats in part of the range have become stabilised and less threatened, given the presence of a protected area in the central part of Madeira reducing the likelihood of habitat degradation. It is listed as Vulnerable (VU) B1ab(iii)+2ab(iii), as the habitats of the sub-populations on Desertas are still threatened by goats, and the loss of these sites and the coastal sites on northern Madeira means that 50% of the subpopulations are still at risk. Should these threats be removed, then the assessment would change to Near Threatened. The previous listing as Near Threatened was based on similar data, but some additional sites have been recognised close to the other localities in the central part of Madeira (Seddon 2008).

Geographic Range:

Actinella actinophora is endemic to the Madeiran Archipelago, where it is found on Madeira and Desertas. Actinella actinophora actinophora is found on the main island of Madeira where it is known from seven locations, several very closely located in the laurisilva zone below Pico Arreiro and Pico Ruivo and three isolated localities on the North Coast of Madeira (Seddon 2008, p.72, 173, Map 94). Actinella actinophora descendens is found on Deserta Grande where it is known from two locations;  there are fossil records from the island of Bugio (Seddon 2008, p.72).

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

Population:

There are no data on population trends

Habitat and Ecology

Actinella actinophora is found in leaf-litter in deep ravines in the laurisilva zone, in rocky areas at high elevations or grassland by the coast. The critical condition is a moist microhabitat with deep leaf-litter.

Major Threat(s):

The threats vary depending on the island locations. On Deserte Grande the habitats were changed radically in the 1900s with the introduction of goats to the island.  Although this island is no longer inhabitated, the goats remained, and the level of grazing has changed the vegetation, leading to considerable soil erosion of the steep slopes.  Until the goats have been eradicated and the vegetation reestablished stablising the slopes, these subpopulations are viewed as extremely vulnerable.

On the north coast of Madeira, the three subpopulations are vulnerable as these lie in areas close of human habitation and roads, with impact of disturbance and change in habitats from non-native plants, grazing and road widening schemes.

On the summit slopes, the laurisilva region lies within a protected area, and so is less susceptible to habitat degradation, however, the small gullies and ravines lie along popular walking paths, and so sites maybe disturbed by 'cleaning' of the sides of the paths to maintain and upgrade the footpaths

Conservation Actions

The species lies in two protected areas, and would benefit from habitat monitoring on Desertas and in the coastal zone of Madeira