As of September 2016, the International Union for Conservation of Nature (IUCN) listed 581 critically endangeredmollusc species, including 117 which are tagged as possibly extinct.[1][2] Of all evaluated mollusc species, 8.0% are listed as critically endangered.
The IUCN also lists 11 mollusc subspecies as critically endangered.
No subpopulations of molluscs have been evaluated by the IUCN.
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.[3] 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".[4]
This is a complete list of critically endangered mollusc species and subspecies evaluated by the IUCN. Species considered possibly extinct by the IUCN are marked as such.
Stylommatophora includes the majority of land snails and slugs. There are 233 species and five subspecies in the order Stylommatophora assessed as critically endangered.
^"IUCN Red List version 2016-2". The IUCN Red List of Threatened Species. International Union for Conservation of Nature and Natural Resources (IUCN). Retrieved 8 September 2016.
^"Limitations of the Data". The IUCN Red List of Threatened Species. Union for Conservation of Nature and Natural Resources (IUCN). Retrieved 11 January 2016.
^"2001 Categories & Criteria (version 3.1)". The IUCN Red List of Threatened Species. Union for Conservation of Nature and Natural Resources (IUCN). Retrieved 11 January 2016.