The Javan Rhinoceros (Sunda Rhinoceros) or Lesser One-horned Rhinoceros (Rhinoceros sondaicus) is a member of the family Rhinocerotidae and one of five surviving rhinoceroses. It belongs to the same genus as the Indian Rhinoceros, but at 3.1–3.2 m in length and 1.4–1.7 m in height, it is smaller. Its horn is usually less than 25 cm (10 inches), smaller than those of the other rhino species.
Once the most widespread of Asian rhinoceroses, the Javan Rhinoceros ranged from the islands of Java and Sumatra, throughout Southeast Asia, and into India and China. The species is now critically endangered, with only one known population in the wild, and none in zoos. It is possibly the rarest large mammal on earth, with a population of as few as 40 in Ujung Kulon National Park on Java in Indonesia. The decline of the Javan Rhinoceros is attributed to poaching, primarily for their horns, which are highly valued in traditional Chinese medicine, fetching as much as $30,000 per kilogram on the black market.
A second population in Cat Tien National Park in Vietnam was confirmed as extinct today, 8th November 2011.