Allenopithecus nigroviridisAllen's swamp monkey

Geographic Range

The range of Allenopithecus nigroviridis is from the Upper and Eastern basins of the Congo to Western Zaire (Walker 1975).


Studies from the Lomako Forest in Zaire suggest that A. nigroviridis is found only in the swamp forests. This differs from many other cercopithecids in that region, which occupy primary, secondary, and Mbau forests. The species is arboreal and at least semi-terrestrial (McGraw 1994).

Physical Description

  • Average mass
    4702.5 g
    165.73 oz


Again little is known about the specific reproductive system of A. nigroviridis. Like other cercopithecids, females generally give birth to one offspring at a time. The young are typically weaned at 2.5 months (Hayssen and Van Tienhoven 1993). The length of estrus and menses is unknown as well as the breeding season. Allenopithecus nigroviridis can live up to 2 decades. (

  • Average number of offspring
  • Average number of offspring
  • Average weaning age
    2.5 months

Females nurse and care for their young for two and a half months.

  • Parental Investment
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • extended period of juvenile learning


These primates are thought to live up to 20 years.


Studies near Mbandaka, Zaire show that A. nigroviridis is diurnal and live in groups of up to 40 or more individuals, with several adult males present. ( Although there is considerable literature concerning the social systems of many species of Old World Monkeys, little is known about the system of A. nigroviridis. It is probably the case that they employ many of the behaviors found in other cercopithecids, including facial expressions of grinning, snarling, as well as many displays of body language, including grimace, dominance and submission (Bernstein 1970). Studies in captivity of A. nigroviridis in the San Diego Zoo suggest that the species is quite social and friendly and similar to guenons (Cercopithecus) in behavior (Walker 1975).

Communication and Perception

Food Habits

Little is known about the overall natural history of A. nigroviridis; however, it is known that they forage on the ground and in shallow water (Walker 1975). The diet of A. nigroviridis includes fruit, leaves, and small invertebrates.

  • Animal Foods
  • insects
  • Plant Foods
  • leaves
  • fruit

Economic Importance for Humans: Positive

Many cercopithecids, including A. nigroviridis, are hunted for their meat, and they are used in the biomedical research industry (Lawlor 1979).

Conservation Status

Other Comments

Studies from the Lomako Forest in Zaire suggest that A. nigroviridis, like other Lomako Forest monkeys, is under a substantial amount of pressure from predators. These predators include the crowned hawk eagle, snakes, and pygmy chimapanzees. In response to these predators, many cercopithecids form poly-specific groups in the various forest types (McGraw 1994).


Corey Sides (author), University of Michigan-Ann Arbor.



living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


uses smells or other chemicals to communicate

  1. active during the day, 2. lasting for one day.

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.


forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.


offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).


having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.


an animal that mainly eats all kinds of things, including plants and animals


rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.


reproduction that includes combining the genetic contribution of two individuals, a male and a female


associates with others of its species; forms social groups.


uses touch to communicate


reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.


Bernstein, I. S. 1970. Old World Monkeys Evolution, Systematics, and Behavior. Academic Press, New York.

Hayssen, V., A.Van Tienhoven, and A. Van Tienhoven. 1993. Asdell's Patterns of Mammalian Reproduction. Cornell University Press, New York.

Lang, H. 1923. A New Genus of African Monkey, Allenopithecus. American Museum Novitates 87:1-5.

Lawlor, T. E. 1979. Handbook to the Orders and Families of Living Mammals. Mad River Press, California.

McGraw S. 1994. Census, Habitat Preference, and Polyspecific Associations of Six Monkeys in the Lomako Forest, Zaire. American Journal of Primatology 34:296-307.

Szalay, F.S and E. Delson. 1979. Evolutionary History of the Primates. Academic Press, New York.

Walker, E. P. 1975. Mammals of the World. Third Edition. John's Hopkins University Press, Baltimore.