IUCN Red List in the context of "Critically endangered"

A species that is extinct in the wild (EW) is one that has been categorized by the International Union for Conservation of Nature as only consisting of living members kept in captivity or as a naturalized population outside its historic range. Classification requires exhaustive surveys conducted within the species' known habitat with consideration given to seasonality, time of day, and life cycle. Once a species is classified as EW, the only way for it to be downgraded is through reintroduction.

Not all EW species are rare. An example is the Brugmansia genus, where all seven species are widely cultivated, but none are found in the wild.

The blood pheasant (Ithaginis cruentus) or blood partridge is a galliforme bird in the pheasant family Phasianidae and the only species in the genus Ithaginis. It is a relatively small, short-tailed pheasant that is widespread in the lower Himalayas ranging across North and East India, Nepal, Bhutan, South China and northern Myanmar. It has been classified as Least Concern on the IUCN Red List since 2009, and the global blood pheasant population is thought to be stable.

The blood pheasant is the state bird of Sikkim, India.

The golden jackal (Canis aureus), also called the common jackal, is a wolf-like canid that is native to Eurasia. The golden jackal's coat varies in color from a pale creamy yellow in summer to a dark tawny beige in winter. It is smaller and has shorter legs, a shorter tail, a more elongated torso, a less-prominent forehead, and a narrower and more pointed muzzle than the Arabian wolf. It is listed as Least Concern on the IUCN Red List due to its widespread distribution and high density in areas with plenty of available food and optimum shelter.

Despite its name, the golden jackal is not closely related to the African black-backed jackal or the side-striped jackal, which are part of the genus Lupulella. It is instead closer to wolves and coyotes. The ancestor of the golden jackal is believed to be the extinct Arno river dog that lived in southern Europe 1.9 million years ago. It is described as having been a small, jackal-like canine. Genetic studies indicate that the golden jackal expanded from India around 20,000 years ago, towards the end of the last Last Glacial Maximum. The oldest golden jackal fossil, found at the Ksar Akil rock shelter near Beirut, Lebanon, is 7,600 years old. The oldest golden jackal fossils in Europe were found in Greece and are 7,000 years old. There are six subspecies of the golden jackal. It is capable of producing fertile hybrids with both the gray wolf and the African wolf. Jackal–dog hybrids called Sulimov dogs are in service at the Sheremetyevo Airport near Moscow, where they are deployed by the Russian airline Aeroflot for scent-detection.

The wild boar (Sus scrofa), also known as the wild swine, common wild pig, Eurasian wild pig, or simply wild pig, is a suid native to much of Eurasia and North Africa, and has been introduced to the Americas and Oceania. The species is now one of the widest-ranging mammals in the world, as well as the most widespread suiform. It has been assessed as least concern on the IUCN Red List due to its wide range, high numbers, and adaptability to a diversity of habitats. It has become an invasive species in part of its introduced range. Wild boars probably originated in Southeast Asia during the Early Pleistocene and outcompeted other suid species as they spread throughout the Old World.

As of 2005, up to 16 subspecies are recognized, which are divided into four regional groupings based on skull height and lacrimal bone length. The species lives in matriarchal societies consisting of interrelated females and their young (both male and female). Fully grown males are usually solitary outside the breeding season. The wolf is the wild boar's main predator in most of its natural range except in the Far East and the Lesser Sunda Islands, where it is replaced by the tiger and Komodo dragon respectively. The wild boar has a long history of association with humans, having been the ancestor of most domestic pig breeds and a big-game animal for millennia. Boars have also re-hybridized in recent decades with feral pigs; these boar–pig hybrids have become a serious pest wild animal in the Americas and Australia.

The green peafowl (Pavo muticus) is a peafowl species native to the tropical forests of Southeast Asia and Indochina. It is the national bird of Myanmar. Formerly common throughout Southeast Asia, only a few isolated populations survive in Cambodia and adjacent areas of Vietnam. It has been listed as endangered on the IUCN Red List since 2009. This is primarily due to widespread deforestation, agriculture and loss of suitable habitat, severely fragmenting populations and contributing to an overall decline in numbers. The green peafowl is in demand for private and home aviculture and threatened by the pet trade, feather collectors and hunters for meat and targeted.

The Congo peafowl (Afropavo congensis), also known as the African peafowl or mbulu by the Bakôngo, is a species native to the Congo Basin. It is one of three species commonly termed "peafowl", and represents the sole extant member of the genus Afropavo, as well as the tribe Pavonini native to Africa. It is listed as Near Threatened on the IUCN Red List.