Bitis nasicornisRhinoceros Viper

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Geographic Range

Bitis nasicornis can be found in the tropical forests throughout Central and Western Africa. Reports as far as Southern Zaire have been documented (Stenstrom 1999).

Habitat

Bitis nasicornis inhabits the tropical forests of Central and Western Africa, often near water, or some sort of swampy environment. Because of this habitat preference it is often called the River Jack (Lipsett 1999). It has, however, been reported in relatively dry forest areas. Mainly terrestrial, it will climb trees, in search of food.

Physical Description

Bitis nasicornis is a short, heavy-bodied snake. Adults have an average length of 60-90 cm (Lipsett 1999). Females are usually the larger of the two, monomorphic sexes. Maximum sizes of up to 1.2 meters are not uncommon (Lipsett 1999). One of the most distinguishing characteristics of Bitis nasicornis is its small-flattened triangular shaped head. Above each nostril are 2-3 horn-like projections (National 1999). Its brilliant coloration is an adaptive feature, and varies among individuals. The color patterns depend on the snake's habitat. It is often considered one of the most beautiful of all snakes.

Reproduction

Bitis nasicornis is a viviparous animal, giving birth to 6-35 young, at the start of the rainy season, (March - April). Young are approximately 18-25 cm, brilliantly colored and venomous (Stenstrom 1999).

Lifespan/Longevity

Behavior

Generally considered a slow moving, somewhat placid animal, Bitis nasicornis is not considered aggressive unless provoked or hungry. If tampered with it will generally puff up and give an extremely loud hiss. It can, however, strike with lightning speed up to half its body length, in any direction (Lipsett 1999).

Food Habits

Small mammals are the main staple, but they are also reported to eat amphibians and fish. Bitis nasicornis is an ambush predator, relying on cryptic coloration as camouflage to hide from their prey. Once grabbed the prey is injected with a single venom, that primarily contains hemotoxic properties, along with some nerotoxic properties. Once injected, the venom attacks primarily the circulatory system of the prey, destroying tissue and blood vessels, causing massive hemorrhaging.

Other Comments

As is true with all snakes in the Viperidae family, Bitis nasicornis periodically (every 6-10 weeks), sheds its fangs.

Contributors

Garry Rogers (author), Michigan State University, James Harding (editor), Michigan State University.

Glossary

Ethiopian

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

World Map

forest

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

native range

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

rainforest

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.

References

Lipsett, J. "Rhinoceros Viper" (On-line). Accessed November 12,1999 at www.whozoo.org/Anlife99/jasonlip/rhinoviperindex.htm.

National Aquarium in Baltimore, .. 1999. Accessed November 12, 1999 at www.aqua.org/animals/species/venom/rhinoviper.html.

Stenstom, E. Accessed November 30, 1999 at http://stud.sbiluth.se/~eriste-6/bitisnas.html.