List of endangered molluscs

In September 2016, the International Union for Conservation of Nature (IUCN) listed 507 endangered mollusc species.[1] Of all evaluated mollusc species, 7.0% are listed as endangered. The IUCN also lists nine mollusc subspecies as endangered.

14 extinct in the wild mollusc species (0.20%)581 critically endangered mollusc species (8.4%)507 endangered mollusc species (7.3%)879 vulnerable mollusc species (13%)535 near threatened mollusc species (7.7%)2437 least concern mollusc species (35%)1988 data deficient mollusc species (29%)
Mollusc species (IUCN, 2020.1)
  • 6941 extant species have been evaluated
  • 4953 of those are fully assessed[a]
  • 2972 are not threatened at present[b]
  • 1967 to 3955 are threatened[c]
  • 324 to 441 are extinct or extinct in the wild:
    • 311 extinct (EX) species[d]
    • 13 extinct in the wild (EW)
    • 117 possibly extinct [CR(PE)]
    • 0 possibly extinct in the wild [CR(PEW)]

  1. ^ excludes data deficient evaluations.
  2. ^ NT, LR/cd, LC.
  3. ^ Threatened comprises CR, EN and VU. Upper estimate additionally includes DD.
  4. ^ Chart omits extinct (EX) species
Endangered (EN) species are considered to be facing a very high risk of extinction in the wild.

No subpopulations of molluscs have been evaluated by the IUCN.

For a species to be considered endangered by the IUCN it must meet certain quantitative criteria which are designed to classify taxa facing "a very high risk of extinction". An even higher risk is faced by critically endangered species, which meet the quantitative criteria for endangered species. Critically endangered molluscs are listed separately. There are 1088 mollusc species which are endangered or critically endangered.

Additionally 1988 mollusc species (27% of those evaluated) are listed as data deficient, meaning there is insufficient information for a full assessment of conservation status. As these species typically have small distributions and/or populations, they are intrinsically likely to be threatened, according to the IUCN.[2] While the category of data deficient indicates that no assessment of extinction risk has been made for the taxa, the IUCN notes that it may be appropriate to give them "the same degree of attention as threatened taxa, at least until their status can be assessed".[3]

This is a complete list of endangered mollusc species and subspecies evaluated by the IUCN.

Gastropods edit

There are 448 species and seven subspecies of gastropod assessed as endangered.

Stylommatophora edit

Stylommatophora is a very diverse group that includes the majority of land snails and slugs. There are 187 species and two subspecies in the order Stylommatophora assessed as endangered.

 
A shell of Eua zebrina
 
A live specimen of Samoa diaphana
 
A live specimen of Newcombia cumingi
 
A shell of Partulina variabilis
 
A gathering of live specimens of Ctenophila setiliris in Réunion
 
A live individual of Gonospira uvula
 
Live individuals of Helix texta
 
A live specimen Iberus gualtieranus
 
Different views of a shell of Xerocrassa montserratensis
 
A live individual of Megalobulimus parafragilior
 
Different views of a shell of Patera clenchi
 
Different views of a shell of Sculptiferussacia clausiliaeformis
 
Several empty shells of Truncatellina arcyensis
 
A shell of Vertigo heldi

Partulids edit

Achatinellids edit

Cerastids edit

Endodontids edit

Charopids edit

Helicarionids edit

Orthalicids edit

Species

Subspecies

Euconulids edit

Streptaxids edit

Species

Subspecies

Camaenids edit

Helicids edit

Hygromiids edit

Other stylommatophoran species edit

Littorinimorpha edit

There are 147 littorinimorph species and three subspecies assessed as endangered.

 
A live individual of Antrobia culveri
 
A live specimen of Belgrandiella wawrai

Hydrobiids edit

Bithyniids edit

Species

Subspecies

Assimineids edit

Pomatiopsids edit

Other Littorinimorpha species edit

Sorbeoconcha edit

Architaenioglossa edit

Species

Subspecies

Cycloneritimorpha edit

Hygrophila species edit

There are 22 Hygrophila species assessed as endangered.

Planorbids edit

Lymnaeids edit

Neogastropoda edit

Other gastropod species edit

Bivalvia edit

There are 57 species and two subspecies in the class Bivalvia assessed as endangered.

Unionida edit

There are 54 species and two subspecies in the order Unionoida assessed as endangered.

Margaritiferids edit

Unionids edit

Species

Subspecies

Other Unionida species edit

Venerida edit

Cephalopods edit

See also edit

References edit

  1. ^ "IUCN Red List version 2016-2". The IUCN Red List of Threatened Species. International Union for Conservation of Nature and Natural Resources. Retrieved 8 September 2016.
  2. ^ "Limitations of the Data". The IUCN Red List of Threatened Species. Union for Conservation of Nature and Natural Resources. Retrieved 11 January 2016.
  3. ^ "2001 Categories & Criteria (version 3.1)". The IUCN Red List of Threatened Species. Union for Conservation of Nature and Natural Resources. Retrieved 11 January 2016.