IUCN SSC Mid-Atlantic Island Invertebrates Specialist Group

Species

BackGeomitra delphinuloides (R. T. Lowe, 1860)

Geomitra delphinuloides (R. T. Lowe, 1860)

  • Kingdom: Animalia
  • Phylum:
  • Class: Mollusca
  • Order: Gastropoda
  • Family: Hygromiidae
CR Critically Endangered
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:
Abreu, C. & Teixeira, D.

Facilitators / Compilers/s:


Assessment Rationale:

The only site where the species was recorded in the last century has never been relocated despite intensive searching over the last 40 years. The distribution of land-snails on the island is well known, hence, as the species is large and conspicuous, the species is probably extinct, but listed as Critically Endangered, Possibly Extinct as the valleys are extremely steep, and hence there remains a possibility that the species has an extremely limited distribution in a remote area which was incorrectly described by Wollaston and Lowe in the original species description.

Geographic Range:

This species is endemic to the Madeiran islands where it is mainly found as a Quaternay fossil at the east end of Madeira (Seddon 2008). Wollaston (1878) has a single record of the species from 1860, where it was found by Reverend Lowe in the Ribeira do Fayal at the foot of perpendicular crags along the new levada called the levada da Fajaa dos Vinhaticos. Since 1980, there have been numerous unsuccessful attempts to locate this site by various collectors such as Waldén, Seddon, Killeen, Colville, Coles, Cameron and Cook (Seddon and Cameron pers. comm. 2008).

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

Population:

This species has not been collected since 1864 and may be extinct.

Habitat and Ecology

The only records are from moist soil surface amongst tufts of ferns, grasses within area of heather and Vaccinium with few laurisilva trees at foot of perpendicular crags (Wollaston 1878).

Major Threat(s):

As this species has not been recorded for nearly 150 years the threats are difficult to establish, however at the time of the last record there was considerable habitat disturbance due to construction of the irrigation levadas on Madeira.

Conservation Actions

This species is listed on the EU Species and Habitats Directive, but has never been relocated despite extensive searches over the last 40 years.