•   Extinct in the wild (EW): 2 species
•   Critically endangered (CR): 393 species
•   Endangered (EN): 626 species
•   Vulnerable (VU): 1,081 species
•   Near threatened (NT, LR/cd): 398 species
•   Least concern (LC): 4,080 species
•   Data deficient (DD): 2,890 species

Arthropod species (IUCN, 2016-2)

• 9470 extant species have been evaluated
• 6580 of those are fully assessed^{[lower-alpha 1]}
• 4478 are not threatened at present^{[lower-alpha 2]}
• 2100 to 4990 are threatened^{[lower-alpha 3]}
• 83 to 169 are extinct or extinct in the wild:
  • 81 extinct (EX) species^{[lower-alpha 4]}
  • 2 extinct in the wild (EW)
  • 86 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

Critically endangered (CR) species face an extremely high risk of extinction in the wild.

As of July 2016, the International Union for Conservation of Nature (IUCN) listed 394 critically endangered arthropod species, including 86 which are tagged as possibly extinct.^[1][2] 4.1% of all evaluated arthropod species are listed as critically endangered. The IUCN also lists three arthropod subspecies as critically endangered.

No subpopulations of arthropods have been evaluated by the IUCN.

Additionally 2875 arthropod species (30% 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 arthropod species and subspecies as evaluated by the IUCN. Species considered possibly extinct by the IUCN are marked as such.

Centipedes

Seed shrimps

• Kapcypridopsis barnardi
• Spelaeoecia bermudensis

Arachnids

There are 47 arachnid species assessed as critically endangered.

Branchiopoda

Millipedes

Entognatha

• Ceratophysella sp. nov. 'HC' (possibly extinct)
• Delamarephorura tami (possibly extinct)

Maxillopoda

Includes barnacles, copepods and a number of related animals.

Malacostracans

Malacostraca includes crabs, lobsters, crayfish, shrimp, krill, woodlice, and many others. There are 125 malacostracan species and one malacostracan subspecies assessed as critically endangered.

Insects

There are 195 insect species and two insect subspecies assessed as critically endangered.

See also

• Lists of IUCN Red List critically endangered species
• List of least concern arthropods
• List of near threatened arthropods
• List of vulnerable arthropods
• List of endangered arthropods
• List of recently extinct arthropods
• List of data deficient arthropods

References