IUCN SSC Mid-Atlantic Island Invertebrates Specialist Group

Species

BackMoreletina obruta (Morelet, 1860)

Moreletina obruta (Morelet, 1860)

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

Countries of Occurrence:
Portugal - Azores

Archipelago(s):
Azores

Assessor/s:
Frias Martins, A.

Reviewer/s:
Neubert, E., Cuttelod, A. & Nichols, C.

Contributor/s:

Facilitators / Compilers/s:


Assessment Rationale:

Due to the highly restricted area and few number of sites where the specimens were found, it is clear that we are dealing with a small population; the disjunct distribution of the two morphs, which could well be two different species, enhances the fact that the diversity within the population is very much at risk due to isolation and small size. The fact that it was first found as a fossil but later found alive enhances the need for protection. This species is considered Vulnerable (VU D2) due to the combination of its small area of occupancy (Area of occupancy = 20 km2), its two unique locations and potential threats from accidental fire and natural events (such as cliff erosion).

Geographic Range:

This species is only found on Santa Maria island, Azores, where it is restricted to two small areas.

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

Population:

This species appears to have a disjunct distribution, the white ecomorph living in Figueiral (N 36º 56.873'; W 25º 07.715'; 100 m) and west of Praia Formosa (coordinate unavailable; 10 m); the black ecomorph was collected east of Anjos (coordinate unavilable; 50 m) and west of Anjos (N 37º 00.481'; W 025º 08.318'; 20 m) (Martins 2002).

Habitat and Ecology

Moreletina obruta lives near the shore on sea cliffs; the white morph lives among gramineae, the black morph under stones. Although there are plenty of dead shells of the white morph, living specimens can be hard to find; the black morph is even rarer.

Major Threat(s):

As this species lives in cliff areas near the sea, only natural threats are foreseeable; however, accidental fires may pose a real threat to the white morph colonies, which live among gramineae.

Conservation Actions

Due to their habitat (cliffs near the sea), only general preventive measures can be advised, such as preventing fires that could destroy the habitat. More taxonomic research is also needed on the two ecomorphs.