Tonkin snub-nosed monkey
- The Tonkin snub-nosed monkey is one of the world’s rarest primates and is endemic to northern Vietnam.
- Groups can number up to 100 individuals.
- The monkeys spend almost all their time in the tree canopy.
- It has a characteristic flat nose with forward-facing nostrils and a long white tail.
- Gestation lasts about 6–7 months.
Age
The tonkin snub-nosed monkey has a typical lifespan of from 15 to 30 years, with a theoretical lifespan ranging from 14 years and 9 months to 29 years and 6 months; the species reaches sexual maturity from 4 to 7 years of age. The young are born with open eyes, and during the embryonic stage, the embryo develops inside the mother. Following this, the infant stage begins, where the offspring is carried by the mother and fed milk for a duration of from 1 day to 2 years. Subsequently, the species enters the adult stage, which lasts from 4 to 30 years, during which time the adult monkey lives in a group, finds food, and can reproduce.
Phenotype
Young Dollman's snub-nosed monkeys have soft, black fur on their backs and lighter fur on their bellies; adult individuals possess thick fur that is black on the back and shoulders and white or creamy on the lower body. The species has strong arms and legs with long fingers for climbing trees, and a short upturned nose with nostrils directed upwards. A long tail aids in balance when jumping between trees.
Physiology
The tonkin snub-nosed monkey’s body height ranges from 17.8 centimeters to 4.5 meters, and its body length varies from 51 to 72 centimeters; the species' mass is between 8 and 14.5 kilograms. During the embryonic stage, the young have a body mass of 1 to 400 grams and a body length of 5 to 15 centimeters. The infant stage sees a body mass from 400 grams to 2.5 kilograms and a body length from 20 to 40 centimeters. An adult individual's body mass is between 8 and 10.5 kilograms, with a body length of 51 to 62 centimeters.
Habitat
Dollman's snub-nosed monkeys inhabit tropical moist forests located between elevations of 200 meters and 1.2 kilometers above sea level; the species lives on land, in forested areas, and in mountainous regions. The climate features dry winters with little precipitation and hot summers exceeding 25 to 30 degrees Celsius; winters are warm and nearly rainless, and summers are warm and pleasant with abundant rainfall. Summers are warm, and winters are not very cold.
Shelter
Tonkin snub-nosed monkeys inhabit the crowns of tall trees and do not have a permanent or long-term shelter; the species utilizes their habitat for protection from predators and for resting, and they lack a fixed den site.
Geography
The tonkin snub-nosed monkey occupies biogeographic regions of Indomalaya and Neotropics, inhabiting ecosystems such as Windward Islands moist forests, Veracruz moist forests, and Yucatan moist forests.
Feeding
The tonkin snub-nosed monkey is herbivorous and obtains food by gathering it with its hands and teeth; its diet consists of young leaves, fruits, buds, flowers, and seeds from trees, as well as vegetable thorns and prickles, young shoots and sprouts, nectar, cones, and fruits. The species’ feeding strategy involves searching for and acquiring food, with a daily food requirement ranging from 350 grams to 0.65 kilograms. It also consumes insects, including beetles, butterflies, diptera, hymenoptera, bedbugs, orthoptera, dragonflies, mayflies, and net-winged insects. In some cultures, the animal is eaten, but it is not considered halal or kosher.
Reproduction
The curly-tailed monkey is a species inhabiting and developing on land, outside of water bodies, reproducing through live birth, with offspring born alive on land, not hatching from eggs or larvae; the female gives birth to one offspring after a gestation period of approximately 200 days, the offspring immediately clings tightly to the mother's fur, the development of the embryo lasts 6 months 1 week, the litter size is 1, the reproductive interval is from 2 to 4 years, sexual reproduction occurs through homogamy, eggs, larvae, or offspring develop in a terrestrial nest built on the ground or close to it, as well as in a nest high in the branches of a bush or tree, maturity occurs from 4 to 7 years, and the offspring consists of one offspring.