Jump to content

Theba macandrewiana

From Wikipedia, the free encyclopedia

Theba macandrewiana
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Order: Stylommatophora
Family: Helicidae
Genus: Theba
Species:
T. macandrewiana
Binomial name
Theba macandrewiana
(L. Pfeiffer, 1853)
Synonyms[1]
  • Helix macandrewiana L. Pfeiffer, 1853
  • Helix mac-andrewiana L. Pfeiffer, 1853
  • Helix ustulata R.T. Lowe, 1852
  • Theba pisana ustulata (Lowe, 1852)

Theba macandrewiana is a species of land snail of the family Helicidae, endemic to the Savage Islands of Portugal. Its shell is around 19.4 millimetres (0.76 in) in length.[2]

Distribution and habitat

[edit]

It is present in the three islands (Selvagem Grande, Selvagem Pequena and Fora Islet) where it occurs on rocky and sandy soils, beneath rocks or associated to grasses from 5 to 160 metres (16 to 525 ft) in altitude. It is the only non-marine gastropod species known from the archipelago.[1]

Threats

[edit]

The species was threatened by previous introduction of rabbits (Oryctolagus cuniculus), mice (Mus musculus) and the tobacco tree (Nicotiana glauca) to the Selvagem Grande which were effectively eradicated in the early 2000's. Today, the species is susceptible to soil erosion and consequent landslides from rainstorms that affect the arid archipelago and also native lizards that may predate on eggs. In the longer term the species could be threatened by increased frequency of droughts and sea level changes due to climate change.[1]

It represents about 35% of the diet of yellow-legged gulls that breed on the islands.[3]

References

[edit]
  1. ^ a b c d Teixeira, D. (2017). "Theba macandrewiana". IUCN Red List of Threatened Species. 2017: e.T157118A742776. doi:10.2305/IUCN.UK.2017-3.RLTS.T157118A742776.en. Retrieved 20 November 2021.
  2. ^ "Theba macandrewiana". conchology.be. Retrieved 27 November 2020.
  3. ^ Matias, Rafael; Catry, Paulo (2010). "The diet of Atlantic Yellow-legged Gulls (Larus michahellis atlantis) at an oceanic seabird colony: estimating predatory impact upon breeding petrels". European Journal of Wildlife Research. 56 (6): 861–869. doi:10.1007/s10344-010-0384-y. hdl:10400.12/2402. S2CID 1582994. Retrieved 27 November 2020.