The white-headed langur in Vietnam has been named in a list of critically endangered species dubbed "Rarest of the Rare" by the Wildlife Conservation Society (WCS).
The list, which appears in the 2010-11 edition of the State of the Wild a Global Portrait report by a US-based NGO, includes birds, mammals, reptiles, and amphibians.
Some are well-known, such as the Sumatran orangutan, while others are more obscure, like vaquita, an ocean porpoise.
The white-headed langur, also known as the Cat Ba langur (Trachypithecus poliocephalus) lives on Cat Ba Island in the northern city of Hai Phong, the report said.
There may be as few as 59 individuals remaining, the result of a 98 percent decline over the last 40 years. The major threats to this species are hunting for "monkey balm," a traditional Chinese medicinal preparation, and the destruction and exploitation of their forest habitat, the report said.
The list of endangered species:
· Cuban crocodile: Currently restricted to two small areas of Cuba.
· Grenada dove: The national bird of Grenada is threatened by habitat loss.
· Florida bonneted bat: Thought to be extinct in 2002, a small colony has since been discovered.
· Green-eyed frog: Only a few hundred of these small amphibians are left.
· Hirola: Also called hunter's hartebeest, the hirola is a highly threatened African antelope.
· Ploughshare tortoise: With only 400 left, the ploughshare tortoise is threatened by the illegal pet trade.
· Island gray fox: Living on the California Channel Islands, this is the smallest fox in the US.
· Sumatran orangutan: This population has declined 80 percent in the past 75 years.
· Vaquita: This small ocean porpoise is drowning in fishing nets.
· White-headed langur: Only 59 of these monkeys remain on a small island off Vietnam.