Jameson's mamba

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Jameson's mamba
Jameson's mamba, (Dendroaspis jamesoni).jpg
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Elapidae
Genus: Dendroaspis
Species: D. jamesoni
Binomial name
Dendroaspis jamesoni
(Traill, 1849)[1][2]
Dendroaspis jamesoni distribution.svg
Range of Jameson's mamba
Both D. j. jamesoni and D. j. kaimosae
Synonyms

D. j. jamesoni:
Traill's green mamba
Jameson's green mamba
D. j. kaimosae:
East African Jameson's mamba

Jameson's mamba (Dendroaspis jamesoni), is a very quick, highly arboreal and highly venomous snake of the family Elapidae.

Description[edit]

Body of the Jameson's mamba.

This species is a long, slightly compressed, very slender bodied snake with a medium length tapering tail that is often yellow in colour.[3][4] The average length of an adult snake of this species is approximately 1.65 meters (5 ft 5 in), but they can grow as long as 2.7 meters (8 ft 10 in).[3][5] They tend to be very similar to the Western green mamba in colouration and like the Western green mamba, the scales of the body of this species have black edgings also. They are usually a dark green, but lighter yellowish green specimens are also common. The ventral side is usually either pale green or yellowish in colour.[4] Jameson's mambas have a narrow and elongated head, with a distinct canthus and slightly distinct from the neck. Like the Western green mamba, the neck may be flattened when the snake is aroused, but there is no real hood. The eyes are medium in size with round pupils. Dorsal scales are oblique, smooth and narrow. Dorsal scale count is 17 (15 or 19) - 17 (15) - 11 (13).[3] The interior of the mouth is tawny or sometimes blue.[6]

Distribution and habitat[edit]

Jameson's mamba occurs mostly in central Africa and some parts of eastern Africa and western Africa. They can be found all the way from northern Angola eastwards towards Zambia, north to the Democratic Republic of Congo, Republic of Congo, Uganda, Rwanda, Kenya, Burundi, South Sudan, Sudan, Central African Republic, Cameroon, Gabon, Ghana, Togo, Nigeria, and Equatorial Guinea.[1][3]

Habitat[edit]

Found in primary and secondary rainforests, woodland and thickets in elevations up to 2,200 metres (7,200 ft) high. An adaptable species, they will persist in areas where there has been extensive deforestation, providing there are still some thickets and trees to hide in. They're also often found atop buildings in villages, in town parks, and farmlands.[3]

Behaviour, diet, and predators[edit]

Behaviour[edit]

This species is highly arboreal, more so than any other mamba species, descending to the ground only in pursuit of prey. Like other mambas, they are diurnal.[3] Jameson's mamba, like other mamba species, will try to use their speed to quickly flee from a perceived threat or use their agility to outmaneuver a predator or a threat and then flee, usually high up in a tree.[7] However, they are very alert, highly nervous and high-strung snakes. Like any other mamba species, if the Jameson's mamba feels that it is cornered or if their threat is persistent, they will become very explosive and aggressive. They will lift their heads up off the ground, hiss loudly, and strike repeatedly.[7]

Diet and predators[edit]

Jameson's mamba will actively pursue their prey, similar to other mamba species. When prey is caught, they will strike rapidly and often until the prey succumbs to the venom.[3] Since this species is arboreal, birds make up a large portion of their diet. Small mammals such as mice, rats, and bats and small lizards are also preyed upon.[8]

The main predators of this species are various birds of prey, including the Martial eagle, Bateleur, and the Congo Serpent Eagle.[7] Other predators may include the honey badger, other snakes, and different species of mongoose may also occasionally prey on the Jameson's mamba.[9]

Etymology[edit]

Jameson's mamba was first described by Traill in 1849. The genus name is derived from the Ancient Greek word - Dendroaspis meaning "tree asp" (dendro is "tree", while aspis is "asp" which is understood to mean a "venomous snake"). The etymology of the name "jamesoni" is unknown.

Venom[edit]

Jamesons Mamba 05.jpg

Like other mambas, the venom of the Jameson's mamba is a highly neurotoxic venom. Its other components include cardiotoxins,[10] and fasciculins.[3] In addition, this mamba species' venom may also have hemotoxic and myotoxic components to it.[11] The average venom yield per bite for this species is 80 mg, but some specimens may yield as much as 120 mg in a single bite. The SC LD50 for this species according to Brown (1973) is 1.0 mg/kg, while the IV LD50 is 0.8 mg/kg.[12] Envenomation by a Jameson's mamba can be deadly in as little as 30 to 120 minutes after being bitten, if proper medical treatment is not attained.[13] However, the average death time for untreated bite victims is usually two to three hours post-envenomation, but it may take up to four to six hours or longer.[8] The mortality rate of untreated bites is not exactly known, but it's said to be very high.[3]

Subspecies[edit]

Subspecies[2] Taxon author[2] Common name Geographic range
D. j. jamesoni (Traill, 1820) Jameson's mamba Throughout much of central Africa including Central African Republic, the Democratic Republic of the Congo, Ghana, Sudan, Gabon, Republic of Congo, Equatorial Guinea, Togo, and northern Angola
D. j. kaimosae (Loveridge, 1936) Black-tailed Jameson's mamba Rwanda, Uganda, Kenya, Sudan, South Sudan, and eastern Democratic Republic of the Congo

References[edit]

  1. ^ a b Uetz, Peter. "Dendroaspis jamesoni (TRAILL, 1843)". The Reptile Database. www.reptile-database.org. Retrieved 27 April 2012. 
  2. ^ a b c "Dendroaspis jamesoni". ITIS Standard Report Page. ITIS.gov. Retrieved 27 April 2012. 
  3. ^ a b c d e f g h i Clinical Toxinology Resource (Dendroaspis jamesoni)
  4. ^ a b Africa's Venomous Snakes
  5. ^ Cincinnati Zoo (Jameson's Mamba)
  6. ^ "SA Reptiles". Jameson's Mamba from Zaire, Northern Angola. Retrieved 2014-11-05. 
  7. ^ a b c Burton, Robert (2002). International Wildlife Encyclopedia: Leopard - marten. USA: Marshall Cavendish. p. 3168. ISBN 0-7614-7277-0. 
  8. ^ a b Zug, George R. (1996). Snakes in Question: The Smithsonian Answer Book. Washington D.C., USA: Smithsonian Institution Scholarly Press. ISBN 1-56098-648-4. 
  9. ^ Mattison, Chris (1987-01-01). Snakes of the World. New York: Facts on File, Inc. p. 164. 
  10. ^ van Aswegen G, van Rooyen JM, Fourie C, Oberholzer G. (May 1996). "Putative cardiotoxicity of the venoms of three mamba species.". Journal of Wilderness and Environmental Medicine 7 (2): 115–21. doi:10.1580/1080-6032(1996)007[0115:PCOTVO]2.3.CO;2. PMID 11990104. 
  11. ^ "Living Hazards Database". Armed Forces Pest Management Board. United States Department of Defense (DoD). Retrieved 11 December 2011. 
  12. ^ Brown, John H. (1973). Toxicology and Pharmacology of Venoms from Poisonous Snakes. Springfield, IL USA: Charles C. Thomas. p. 81. ISBN 0-398-02808-7. 
  13. ^ Davidson, Terence. "IMMEDIATE FIRST AID". University of California, San Diego. Retrieved 2011-11-10. 

External links[edit]