Rock monitor

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Rock monitor
White-throated Monitor (Varanus albigularis) (5984080381).jpg
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Family: Varanidae
Genus: Varanus
Subgenus: Polydaedalus
Species: V. albigularis
Binomial name
Varanus albigularis
Daudin, 1802[1][2]

The rock monitor (Varanus albigularis), also called the black-throated monitor, is a species of monitor lizard found in Central, East, and southern Africa. It is the second-longest lizard found on the continent, and the heaviest-bodied; locally, it is called leguaan or likkewaan.


First described by François Marie Daudin in 1802,[1] these lizards were previously classified as a subspecies of Varanus exanthematicus,[3] but have since been declared a distinct species based upon differences in hemipenal morphology.[4] The generic name Varanus is derived from the Arabic word waral ورل, which is translated to English as "monitor". Their specific name comes from a compound of two Latin words: albus meaning "white" and gula meaning "throat".

The subspecies of V. albigularis are:


This is the heaviest-bodied lizard in Africa, as adult males average about 6 to 8 kg (13 to 18 lb) and females weigh from 3.2 to 5 kg (7.1 to 11.0 lb).[6][7][8] Large mature males can attain 15 to 17 kg (33 to 37 lb).[9] It is the second longest African lizard after the Nile monitor, Varanus albigularis reaches 2 meters (6 ft 7 in) in length, with its tail and body being of equal size.[10] Mature specimens more typically will measure 0.85 to 1.5 meters (2 ft 9 in to 4 ft 11 in).[7][9] The head and neck are the same length, and are distinct from each other.[11] Their bulbous, convex snouts give an angular, box-like appearance. Their forked tongues are pink or bluish,[11] and their scales are usually a mottled gray-brown with yellowish or white markings.[11]


An intelligent lizard, several specimens have demonstrated the ability to count as high as six in an experiment conducted by Dr. John Philips at the San Diego Zoo in 1999.[12] Philips offered varying numbers of snails, and the monitors were able to distinguish numbers whenever one was missing.[13][14]


This monitor ranges in these areas: Central Africa (Democratic Republic of the Congo/Zaire), Southern Africa (Namibia, Botswana, Republic of South Africa, Swaziland, Zimbabwe, Mozambique, Zambia, Angola), the African Great Lakes (Kenya, Uganda, Tanzania), and the Horn of Africa (Ethiopia, Somalia).[11] It is found in a variety of dry habitats, including steppes, prairies, and savannahs, but is absent from desert interiors, rainforests, and thick scrub forests.[11]


People living with the HIV/AIDS virus in Yumbe district of Uganda have been reported injecting themselves with the blood of rock monitors, which they believe to be a cure for the virus.[15] Many are reportedly discontinuing antiretroviral therapy to pursue this anecdotal treatment.[15] As a result, V. albigularis is reported to have become an expensive item in the Ugandan black market, selling for more than US$175 each.[15]


  1. ^ a b Daudin, F. M. (1802). Histoire Naturelle, génerale et particulièredes reptiles, ouvrage faisant suite, a l'histoiure naturelle, générale et particulière composée par LECLERC DE BUFFON, et redigée par C. S. SONNINI, vol. 3. F. Dufart, Paris.
  2. ^ "Varanus albigularis". Integrated Taxonomic Information System. Retrieved 22 August 2008. 
  3. ^ Laurent,R.F. 1964. A new subspecies of Varanus exanthematicus (Sauria, Varanidae). Breviora 199: 1–5
  4. ^ Bohme, W. (1991). New finding on the hemipenal morphology of monitor lizards and their systematic implications. Mertensiella, 2, 42–49.
  5. ^
  6. ^ "White Throated Monitor - Varanus albigularis". Reptiliana: Ultimate Reptile Resource. Retrieved 2013-06-06. 
  7. ^ a b "African Savannah Monitor - Varanus exanthematicus albigularis". WAZA : World Association of Zoos and Aquariums. Retrieved 2013-06-06. 
  8. ^ MLA Gardner, B. R., and M. G. Barrows. "Yolk coelomitis in a white-throated monitor lizard (Varanus albigularis)." Journal of the South African Veterinary Association 81.2 (2010): 121-122. APA Gardner, B. R., & Barrows, M. G. (2010). Yolk coelomitis in a white-throated monitor lizard (Varanus albigularis). Journal of the South African Veterinary Association, 81(2), 121-122. Chicago Gardner, B. R., and M. G. Barrows. Yolk coelomitis in a white-throated monitor lizard (Varanus albigularis). Journal of the South African Veterinary Association 81, no. 2 (2010): 121-122.
  9. ^ a b "Varanus albigularis". Archived from the original on 2012-07-31. Retrieved 2013-06-06. 
  10. ^ Carruthers, Vincent (June 5, 2008). The Wildlife of Southern Africa: The Larger Illustrated Guide to the Animals and Plants of the Region. South Africa: Struik Publishers. p. 320. ISBN 978-1-77007-199-5. 
  11. ^ a b c d e Alexander, Grahm; Marais, Johan (2008). A Guide to the Reptiles of Southern Africa. South Africa: Struik Publishers. p. 408. ISBN 978-1-77007-386-9. 
  12. ^ Pianka, Eric R.; Vitt, Laurie J. (2003). Lizards: Windows to the Evolution of Diversity (Organisms and Environments, 5). 5 (1 ed.). California: University of California Press. ISBN 978-0-520-23401-7. 
  13. ^ King, Dennis & Green, Brian. (1999). Goannas: The Biology of Varanid Lizards. University of New South Wales Press. ISBN 0-86840-456-X, p. 43.
  14. ^ The Weekend Australian. July 24–25, 1999, p. 12.
  15. ^ a b c "Ugandans turn to varanid lizard blood for AIDS cure" (PDF). BIAWAK. INTERNATIONAL VARANID INTEREST GROUP. 2 (1). February 2008. Retrieved 2008-08-27. 

Further reading[edit]

  • Photo of Varanus albigularis
  • (1992). The Necropsy and internal Anatomy of a white-throated monitor lizard (Varanus albigularis Daudin, 1802). VaraNews 2(1): 5-6.