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                           List of Endangered Monkeys

Greater bamboo lemur (Prolemur simus)
Madagascar

White-collared lemur (Eulemur albocollaris)
Madagascar

Perrier's sifaka (Propithecus perrieri)
Madagascar

Silky sifaka (Propithecus candidus)
Madagascar

Eastern gorilla (Gorilla beringei)
Democratic Republic of Congo, Rwanda, Uganda

Cross River gorilla (Gorilla gorilla diehli)
Nigeria, Cameroon

Mt. Rungwe galago (an as yet undescribed form of the genus Galagoides)
Tanzania

Tana River red colobus (Procolobus rufomitratus)
Kenya

White-naped mangabey (Cercocebus atys lunulatus)
Ghana, Ivory Coast

Sanje mangabey (Cercocebus sanjei)
Tanzania

Bioko red colobus (Procolobus pennantii pennantii)
Equatorial Guinea (Island of Bioko)

Black-faced lion tamarin (Leontopithecus caissara)
Brazil

Buffy-headed tufted capuchin (Cebus xanthosternos)
Brazil

Northern muriqui (Brachyteles hypoxanthus)

Brown spider monkey (Ateles hybridus brunneus)
Colombia

Horton Plains slender loris (Loris lydekkerianus nycticeboides)
Sri Lanka

Miller's grizzled surili (Presbytis hosei canicrus)
Indonesia (Kalimantan)

Pagai pig-tailed snub-nosed monkey (Simias concolor)
Indonesia (Mentawai Islands)

Delacour's langur (Trachypithecus delacouri)
Vietnam

Golden-headed langur (Trachypithecus poliocephalus poliocephalus)
Vietnam

Western purple-faced langur (Semnopithecus vetulus nestor)
Sri Lanka

Grey-shanked douc (Pygathrix nemaeus cinerea)
Vietnam

Tonkin snub-nosed monkey (Rhinopithecus avunculus)
Vietnam

Hainan black-crested gibbon (Nomascus nasutus hainanus)
China (Hainan Island)

Sumatran orangutan (Pongo abelii)
Indonesia (Sumatra)