All species listed as "Extinct" are classified as being extinct (no known remaining individuals left) by the International Union for Conservation of Nature (IUCN). All species listed as Extinct in the wild are classified as being extinct in the wild, meaning that all remaining individuals of the species reside in captivity. All species listed as "Possibly extinct" are classified as being critically endangered, as it is unknown whether or not these species are extinct.[5] Extinct subspecies such as the Javan tiger (Panthera tigris sondaica)[6] are not listed here as the species, in this case Panthera tigris, is still extant. The IUCN Redlist classification for each species serves as a citation, and the superscripted "IUCN" by the date is a link to that species' page. A range map is provided wherever available, and a description of their former or current range is given if a range map is not available.