No reasonable doubt that the last individual has died.
EW
Extinct in the wild
Known only to survive in captivity or as a naturalized populations well outside its previous range.
CR
Critically endangered
The species is in imminent risk of extinction in the wild.
EN
Endangered
The species is facing an extremely high risk of extinction in the wild.
VU
Vulnerable
The species is facing a high risk of extinction in the wild.
NT
Near threatened
The species does not meet any of the criteria that would categorise it as risking extinction but it is likely to do so in the future.
LC
Least concern
There are no current identifiable risks to the species.
DD
Data deficient
There is inadequate information to make an assessment of the risks to this species.
Some species were assessed using an earlier set of criteria. Species assessed using this system have the following instead of near threatened and least concern categories:
LR/cd
Lower risk/conservation dependent
Species which were the focus of conservation programmes and may have moved into a higher risk category if that programme was discontinued.
LR/nt
Lower risk/near threatened
Species which are close to being classified as vulnerable but are not the subject of conservation programmes.
LR/lc
Lower risk/least concern
Species for which there are no identifiable risks.
Rodents make up the largest order of mammals, with over 40% of mammalian species. They have two incisors in the upper and lower jaw which grow continually and must be kept short by gnawing. Most rodents are small though the capybara can weigh up to 45 kg (99 lb). Three species of rodents (voles) have been discovered only in recent three decades: European pine vole,[2]East European vole,[3] and Tundra vole.[4]
The lagomorphs comprise two families, Leporidae (hares and rabbits), and Ochotonidae (pikas). Though they can resemble rodents, and were classified as a superfamily in that order until the early twentieth century, they have since been considered a separate order. They differ from rodents in a number of physical characteristics, such as having four incisors in the upper jaw rather than two.
The order Erinaceomorpha contains a single family, Erinaceidae, which comprise the hedgehogs and gymnures. The hedgehogs are easily recognised by their spines while gymnures look more like large rats.
The bats' most distinguishing feature is that their forelimbs are developed as wings, making them the only mammals capable of flight. Bat species account for about 20% of all mammals.
The order Cetacea includes whales, dolphins and porpoises. They are the mammals most fully adapted to aquatic life with a spindle-shaped nearly hairless body, protected by a thick layer of blubber, and forelimbs and tail modified to provide propulsion underwater.
The even-toed ungulates are ungulates whose weight is borne about equally by the third and fourth toes, rather than mostly or entirely by the third as in perissodactyls. There are about 220 artiodactyl species, including many that are of great economic importance to humans.
^This list is derived from the IUCN Red List which lists species of mammals and includes those mammals that have recently been classified as extinct (since 1500 AD). The taxonomy and naming of the individual species is based on those used in existing Wikipedia articles as of 21 May 2007 and supplemented by the common names and taxonomy from the IUCN, Smithsonian Institution, or University of Michigan where no Wikipedia article was available.
^Baltrūnaitė, L. 2010. Microtus subterraneus de Sélys-Longchamps, 1836: A new mammal species for the Latvian fauna. Acta Zoologica Lituanica, 20 (1): 37–38.
^Zagorodnjuk, I., M. Masing, V. Peskov. 1991. Põld-uruhiire teisikliigid Eestis [Sibling species of Common Vole in Estonia]. Eesti Loodus, No. 11: 674–678.
^Balčiauskas, L. 2014. New mammal species for Latvia, the root vole (Microtus oeconomus). Zoology and Ecology, 24 (3): 187–191.
