Monitor lizards are

lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...

s in the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

''Varanus,'' the only extant genus in the family

Varanidae The Varanidae are a family of lizards in the superfamily Varanoidea within the Anguimorpha group. The family, a group of carnivorous and frugivorous lizards, includes the living genus '' Varanus'' and a number of extinct genera more closely relat ...

. They are native to Africa, Asia, and

Oceania Oceania (, , ) is a region, geographical region that includes Australasia, Melanesia, Micronesia, and Polynesia. Spanning the Eastern Hemisphere, Eastern and Western Hemisphere, Western hemispheres, Oceania is estimated to have a land area of ...

, and one species is also found in the Americas as an

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

. About 80 species are recognized. Monitor lizards have long necks, powerful

tail The tail is the section at the rear end of certain kinds of animals’ bodies; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, r ...

s and claws, and well-developed limbs. The adult length of extant species ranges from in some species, to over in the case of the

Komodo dragon The Komodo dragon (''Varanus komodoensis''), also known as the Komodo monitor, is a member of the monitor lizard family Varanidae that is endemic to the Indonesian islands of Komodo, Rinca, Flores, and Gili Motang. It is the largest extant ...

, though the extinct

varanid The Varanidae are a family of lizards in the superfamily Varanoidea within the Anguimorpha group. The family, a group of carnivorous and frugivorous lizards, includes the living genus '' Varanus'' and a number of extinct genera more closely relat ...

known as

megalania Megalania (''Varanus priscus'') is an extinct species of giant monitor lizard, part of the megafaunal assemblage that inhabited Australia during the Pleistocene. It is the largest terrestrial lizard known to have existed, reaching an estimated ...

(''Varanus priscus'') may have been capable of reaching lengths more than . Most monitor species are

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

, but

arboreal Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...

and semiaquatic monitors are also known. While most monitor lizards are

carnivorous A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...

, eating

egg An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the a ...

s, smaller reptiles,

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...

s, and small mammals, some also eat

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

and

vegetation Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic character ...

, depending on where they live.

Distribution

The various species

cover Cover or covers may refer to: Packaging * Another name for a lid * Cover (philately), generic term for envelope or package * Album cover, the front of the packaging * Book cover or magazine cover ** Book design ** Back cover copy, part of co ...

a vast area, occurring through Africa, the

Indian subcontinent The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian O ...

, to

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

, the

Ryukyu Islands The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Taiwan: the Ōsumi, Tokara, Amami, Okinawa, and Sakishima Islands (further divided into the Miyako and Yaeyama Islands), with Yonaguni ...

in southern

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

, south to

Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...

Malaysia Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...

Brunei Brunei ( , ), formally Brunei Darussalam ( ms, Negara Brunei Darussalam, Jawi alphabet, Jawi: , ), is a country located on the north coast of the island of Borneo in Southeast Asia. Apart from its South China Sea coast, it is completely sur ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

, the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

New Guinea New Guinea (; Hiri Motu Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea). It is a simplified version of ...

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

, and islands of the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...

and the

South China Sea The South China Sea is a marginal sea of the Western Pacific Ocean. It is bounded in the north by the shores of South China (hence the name), in the west by the Indochinese Peninsula, in the east by the islands of Taiwan and northwestern Phil ...

. The

West African Nile monitor The West African Nile monitor (''Varanus niloticus stellatus'') is a species of monitor lizard that is native to West African forests and adjacent savannah (east to northern Cameroon). It has also been introduced to Florida, United States, whe ...

(''Varanus stellatus'') is now found in

South Florida South Florida is the southernmost region of the U.S. state of Florida. It is one of Florida's three most commonly referred to directional regions; the other two are Central Florida and North Florida. South Florida is the southernmost part of th ...

. Monitor lizards also occurred widely in Europe in the

Neogene The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...

, with the last known remains in the region dating to the

Middle Pleistocene The Chibanian, widely known by its previous designation of Middle Pleistocene, is an age in the international geologic timescale or a stage in chronostratigraphy, being a division of the Pleistocene Epoch within the ongoing Quaternary Period. The ...

Habits and diet

Most monitor lizards are almost entirely carnivorous, consuming prey as varied as insects,

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...

arachnid Arachnida () is a class of joint-legged invertebrate animals (arthropods), in the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, harvestmen, camel spiders, whip spiders and vinegaroon ...

myriapod Myriapods () are the members of subphylum Myriapoda, containing arthropods such as millipedes and centipedes. The group contains about 13,000 species, all of them terrestrial. The fossil record of myriapods reaches back into the late Silurian, a ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

s, fish,

amphibian Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...

s, reptiles, birds, and mammals. Most species feed on invertebrates as juveniles and shift to feeding on vertebrates as adults. Deer make up about 50% of the diet of adults of the largest species, ''

Varanus komodoensis The Komodo dragon (''Varanus komodoensis''), also known as the Komodo monitor, is a member of the monitor lizard family Varanidae that is endemic to the Indonesian islands of Komodo (island), Komodo, Rinca, Flores, and Gili Motang. It is the ...

''. In contrast, three

species from the Philippines, ''

Varanus bitatawa The Northern Sierra Madre forest monitor (''Varanus bitatawa''), also known by the local names ''bitatawa'', ''baritatawa'', and ''butikaw'', is a large, arboreal, frugivorous lizard of the genus '' Varanus''. The lizard is a distinctive food of ...

'', ''

Varanus mabitang The Panay monitor (''Varanus mabitang'') is an endangered monitor lizard native to Panay Island in the Philippines. Unlike most monitors, it is a specialized frugivore. Distribution and habitat The Panay monitor occurs only on Panay, inhabitin ...

'', and ''

Varanus olivaceus The Gray's monitor (''Varanus olivaceus'') is a large (180 cm, >9 kg) monitor lizard known only from lowland dipterocarp forest in southern Luzon, Catanduanes, and Polillo Island, all islands in the Philippines. It is also known as Gr ...

'', are primarily fruit eaters. Although normally solitary, groups as large as 25 individual monitor lizards are common in ecosystems that have limited water resources.

Biology

The genus ''Varanus'' is considered unique among animals in that its members are relatively morphologically conservative, yet show a very large size range. Finer morphological features such as the shape of the skull and limbs do vary, though, and are strongly related to the ecology of each species. Monitor lizards maintain large territories and employ active-pursuit hunting techniques that are reminiscent of similar-sized mammals.King, D., Green, B., Knight, F. (1999). ''Monitors: The Biology of Varanid Lizards.'' Florida. Krieger Publishing Company. The active nature of monitor lizards has led to numerous studies on the metabolic capacities of these lizards. The general consensus is that monitor lizards have the highest standard metabolic rates of all

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...

reptiles.Pianka, E.R., Vitt, L.J. (2003). ''Lizards: Windows to the Evolution of Diversity.'' California. University of California Press. Monitor lizards have a high aerobic scope that is afforded, in part, by their heart anatomy. Whereas most reptiles are considered to have three-chambered hearts, the hearts of monitor lizards – as with those of boas and

pythons The Pythonidae, commonly known as pythons, are a family of nonvenomous snakes found in Africa, Asia, and Australia. Among its members are some of the largest snakes in the world. Ten genera and 42 species are currently recognized. Distribution ...

– have a well developed ventricular septum that completely separates the

pulmonary The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of th ...

and

systemic Systemic fundamental to a predominant social, economic, or political practice. This refers to: In medicine In medicine, ''systemic'' means affecting the whole body, or at least multiple organ systems. It is in contrast with ''topical'' or ''loc ...

sides of the circulatory system during

systole Systole ( ) is the part of the cardiac cycle during which some chambers of the heart contract after refilling with blood. The term originates, via New Latin, from Ancient Greek (''sustolē''), from (''sustéllein'' 'to contract'; from ''sun ...

. This allows monitor lizards to create mammalian-equivalent pressure differentials between the pulmonary and systemic circuits, which in turn ensure that oxygenated blood is quickly distributed to the body without also flooding the lungs with high-pressure blood. Anatomical and molecular studies indicate that all varanids (and possibly all lizards) are partially

venom Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...

ous. The venom of monitor lizards is diverse and complex, as a result of the diverse ecological niches monitor lizards occupy. Monitor lizards are

oviparous Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and ...

, laying from seven to 38

eggs Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...

, which they often cover with soil or protect in a hollow tree stump. Some monitor lizards, including the Komodo dragon, are capable of

parthenogenesis Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and development ...

Evolution

''Varanus'' is the only living member of the family

. Varanidae last shared a common ancestor with their closest living relatives, earless "monitors", during the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

. The oldest known members of Varanidae are known from the

of Mongolia. During the

Eocene The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...

, the varanid ''

Saniwa ''Saniwa'' is an extinct genus of varanid lizard that lived about 48 million years ago during the Eocene epoch. It is known from well-preserved fossils found in the Bridger and Green River Formations of Wyoming. The type species ''S. ensidens'' ...

'' occurred in North America. The closest known relative of ''Varanus'' is ''

Archaeovaranus ''Archaeovaranus'' (meaning "ancient '' Varanus''") is genus of varanid lizard from the early Eocene (Ypresian) Yuhuangding Formation of Hubei Province, China. The genus contains a single species, ''Archaeovaranus lii'', known from a nearly comp ...

'' from the Eocene of China, suggesting that the genus ''Varanus'' is of Asian origin. The oldest fossils of ''Varanus'' date to the early

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

. Many of the species within the various

subgenera In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...

also form

species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

es with each other: ''V. indicus'' species complex (''V. indicus'', ''V. cerambonensis'', ''V. caerulivirens'', ''V. colei'', ''V. obor'', ''V. lirugensis'', ''V. rainerguentheri'', ''V. zugorum'') ''V. doreanus'' species complex (''V. doreanus'', ''V. finschi'', ''V. semotus'', ''V. yuwonoi'') ''V. gouldii'' species complex (''V. gouldii'', ''V. rosenbergi'', ''V. panoptes'') ''V. bengalensis'' species complex (''V. bengalensis'', ''V. nebulosus'') ''V. acanthurus'' species complex (''V. acanthurus'', ''V. baritji'', ''V. primordius'', ''V. storri'') ''V. exanthematicus'' species complex (''V. exanthematicus'', ''V. albigularis'', ''V. yemenensis'') ''V. timorensis'' species complex (''V. timorensis'', ''V. auffenbergi'', ''V. scalaris'', ''V. similis'', ''V. tristis)'' ''V. niloticus'' species complex (''V. niloticus'', ''V. stellatus'') ''V. salvator'' species complex (''V. salvator'', ''V. cumingi'', ''V. nuchalis'', ''V. togianus'', ''V. marmoratus'') The tree monitors of the ''V. prasinus'' species complex (''V. prasinus'', ''V. beccarii'', ''V. boehmei'', ''V. bogerti'', ''V. keithhornei'', ''V. kordensis'', ''V. macraei'', ''V. reisingeri'', ''V. telenesetes'') were once in the subgenus ''Euprepriosaurus'', but as of 2016, form their own subgenus ''

Hapturosaurus The subgenus ''Hapturosaurus,'' sometimes known as the tree monitors, consists of slender-bodied arboreal monitor lizards mostly found in the tropical rainforests of Indonesia and Papua New Guinea. Taxonomy The type species is the green tree ...

''. ''V. jobiensis'' was once considered to be a member of the ''V. indicus'' species complex, but is now considered to represent its own species complex.

Etymology

The

generic Generic or generics may refer to: In business * Generic term, a common name used for a range or class of similar things not protected by trademark * Generic brand, a brand for a product that does not have an associated brand or trademark, other ...

name ''Varanus'' is derived from the

Arabic Arabic (, ' ; , ' or ) is a Semitic languages, Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C ...

word ''waral'' tandard Arabic/ ''warar'' olloquially/ ''waran'' olloquially from a common Semitic root ''ouran'', ''waran'', ''warar'' or '' waral'', meaning "lizard beast". In English, they are known as "monitors" or "monitor lizards". The earlier term "monitory lizard" became rare by about 1920. The name may have been suggested by the occasional habit of varanids to stand on their two hind legs and to appear to "monitor", or perhaps from their supposed habit of "warning persons of the approach of venomous animals". But all of these explanations for the name "monitor" postdate Linnaeus giving the scientific name ''Lacerta monitor'' to the

Nile monitor The Nile monitor (''Varanus niloticus'') is a large member of the monitor family (Varanidae) found throughout most of Sub-Saharan Africa and along the Nile, with invasive populations in North America. The population in West African forests and sa ...

in 1758, which may have been based on a mistaken idea by

Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

that the

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...

word ''Waran'' (borrowed from Arabic) was connected to ''warnen'' (to warn), leading him to incorrectly

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

ize it as into ''monitor'' (warner, adviser). In

Austronesia The Austronesian peoples, sometimes referred to as Austronesian-speaking peoples, are a large group of peoples in Taiwan, Maritime Southeast Asia, Micronesia, coastal New Guinea, Island Melanesia, Polynesia, and Madagascar that speak Austrone ...

, where varanids are common, they are known under a large number of local names. They are usually known as ''biawak'' (

Malay Malay may refer to: Languages * Malay language or Bahasa Melayu, a major Austronesian language spoken in Indonesia, Malaysia, Brunei and Singapore ** History of the Malay language, the Malay language from the 4th to the 14th century ** Indonesi ...

, including

Indonesian Indonesian is anything of, from, or related to Indonesia, an archipelagic country in Southeast Asia. It may refer to: * Indonesians, citizens of Indonesia ** Native Indonesians, diverse groups of local inhabitants of the archipelago ** Indonesian ...

standard variety), ''bayawak'' (

Filipino Filipino may refer to: * Something from or related to the Philippines ** Filipino language, standardized variety of 'Tagalog', the national language and one of the official languages of the Philippines. ** Filipinos, people who are citizens of th ...

), ''binjawak'' or ''minjawak or nyambik'' ( Javanese), or variations thereof. Other names include ''hokai'' (

Solomon Islands Solomon Islands is an island country consisting of six major islands and over 900 smaller islands in Oceania, to the east of Papua New Guinea and north-west of Vanuatu. It has a land area of , and a population of approx. 700,000. Its capita ...

); ''bwo'', ''puo'', or ''soa'' ( Maluku); ''halo'' (

Cebu Cebu (; ceb, Sugbo), officially the Province of Cebu ( ceb, Lalawigan sa Sugbo; tl, Lalawigan ng Cebu; hil, Kapuroan sang Sugbo), is a province of the Philippines located in the Central Visayas region, and consists of a main island and 167 ...

); ''galuf'' or ''kaluf'' (

Micronesia Micronesia (, ) is a subregion of Oceania, consisting of about 2,000 small islands in the western Pacific Ocean. It has a close shared cultural history with three other island regions: the Philippines to the west, Polynesia to the east, and ...

and the

Caroline Islands The Caroline Islands (or the Carolines) are a widely scattered archipelago of tiny islands in the western Pacific Ocean, to the north of New Guinea. Politically, they are divided between the Federated States of Micronesia (FSM) in the centra ...

); ''batua'' or ''butaan'' (

Luzon Luzon (; ) is the largest and most populous island in the Philippines. Located in the northern portion of the Philippines archipelago, it is the economic and political center of the nation, being home to the country's capital city, Manila, as ...

); ''alu'' (

Bali Bali () is a province of Indonesia and the westernmost of the Lesser Sunda Islands. East of Java and west of Lombok, the province includes the island of Bali and a few smaller neighbouring islands, notably Nusa Penida, Nusa Lembongan, and Nu ...

); ''hora'' or ''ghora'' (

Komodo Komodo may refer to: Computers * Komodo Edit, a free text editor for dynamic programming languages * Komodo IDE an integrated development environment (IDE) for dynamic programming languages * Komodo (chess), a chess engine People * Komodo ...

group of islands); ''phut'' (

Burmese Burmese may refer to: * Something of, from, or related to Myanmar, a country in Southeast Asia * Burmese people * Burmese language * Burmese alphabet * Burmese cuisine * Burmese culture Animals * Burmese cat * Burmese chicken * Burmese (hor ...

); and ''guibang'' (

Manobo The Lumad are a group of Austronesian indigenous people in the southern Philippines. It is a Cebuano term meaning "native" or "indigenous". The term is short for Katawhang Lumad (Literally: "indigenous people"), the autonym officially adopte ...

). In

South Asia South Asia is the southern subregion of Asia, which is defined in both geographical and ethno-cultural terms. The region consists of the countries of Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka.;;;;;;;; ...

, they are known as in Meitei, mwpou in Boro, घोरपड in

Marathi Marathi may refer to: *Marathi people, an Indo-Aryan ethnolinguistic group of Maharashtra, India *Marathi language, the Indo-Aryan language spoken by the Marathi people *Palaiosouda, also known as Marathi, a small island in Greece See also * * ...

, உடும்பு in

Tamil Tamil may refer to: * Tamils, an ethnic group native to India and some other parts of Asia ** Sri Lankan Tamils, Tamil people native to Sri Lanka also called ilankai tamils **Tamil Malaysians, Tamil people native to Malaysia * Tamil language, nati ...

and

Malayalam Malayalam (; , ) is a Dravidian language spoken in the Indian state of Kerala and the union territories of Lakshadweep and Puducherry (Mahé district) by the Malayali people. It is one of 22 scheduled languages of India. Malayalam was des ...

, in

Bhojpuri Bhojpuri (;Bhojpuri entry, Oxford Dictionaries
, Oxford U ...

, ''gohi'' (गोहि) in Maithili, in Sinhala as තලගොයා / කබරගොයා (), in

Telugu Telugu may refer to: * Telugu language, a major Dravidian language of India *Telugu people, an ethno-linguistic group of India * Telugu script, used to write the Telugu language ** Telugu (Unicode block), a block of Telugu characters in Unicode S ...

as ''uḍumu'' (ఉడుము), in

Kannada Kannada (; ಕನ್ನಡ, ), originally romanised Canarese, is a Dravidian language spoken predominantly by the people of Karnataka in southwestern India, with minorities in all neighbouring states. It has around 47 million native s ...

as (ಉಡ), in

Punjabi Punjabi, or Panjabi, most often refers to: * Something of, from, or related to Punjab, a region in India and Pakistan * Punjabi language * Punjabi people * Punjabi dialects and languages Punjabi may also refer to: * Punjabi (horse), a British Th ...

and

Magahi The Magahi language (), also known as Magadhi (), is a language spoken in Bihar, Jharkhand and West Bengal states of eastern India, and in the Terai of Nepal. Magadhi Prakrit was the ancestor of Magahi, from which the latter's name derives. ...

as गोह (''goh''), in

Assamese Assamese may refer to: * Assamese people, a socio-ethnolinguistic identity of north-eastern India * People of Assam, multi-ethnic, multi-linguistic and multi-religious people of Assam * Assamese language, one of the easternmost Indo-Aryan language ...

as ''gui xaap'', in

Odia Odia, also spelled Oriya or Odiya, may refer to: * Odia people in Odisha, India * Odia language, an Indian language, belonging to the Indo-Aryan branch of the Indo-European language family * Odia alphabet, a writing system used for the Odia languag ...

as ଗୋଧି (''godhi''), and in

Bengali Bengali or Bengalee, or Bengalese may refer to: *something of, from, or related to Bengal, a large region in South Asia * Bengalis, an ethnic and linguistic group of the region * Bengali language, the language they speak ** Bengali alphabet, the w ...

as গোসাপ () or গুইসাপ (), and गोह (''goh'') in

Hindi Hindi (Devanāgarī: or , ), or more precisely Modern Standard Hindi (Devanagari: ), is an Indo-Aryan language spoken chiefly in the Hindi Belt region encompassing parts of northern, central, eastern, and western India. Hindi has been de ...

. In

West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa as the 16 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia, Mali, Maurit ...

, the nile monitor is known by several names in

Yoruba The Yoruba people (, , ) are a West African ethnic group that mainly inhabit parts of Nigeria, Benin, and Togo. The areas of these countries primarily inhabited by Yoruba are often collectively referred to as Yorubaland. The Yoruba constitute ...

, including , , and . Due to confusion with the large New World lizards of the family

Iguanidae The Iguanidae is a family of lizards composed of the iguanas, chuckwallas, and their prehistoric relatives, including the widespread green iguana. Taxonomy Iguanidae is thought to be the sister group to the collared lizards (family Crotaph ...

, the lizards became known as "

goannas A goanna is any one of several species of lizards of the genus '' Varanus'' found in Australia and Southeast Asia. Around 70 species of ''Varanus'' are known, 25 of which are found in Australia. This varied group of carnivorous reptiles ranges ...

" in Australia. Similarly, in

South African English South African English (SAfrE, SAfrEng, SAE, en-ZA) is the set of English language dialects native to South Africans. History British settlers first arrived in the South African region in 1795, when they established a military holding op ...

, they are referred to as ''leguaans'', or ''likkewaans'', from the

Dutch Dutch commonly refers to: * Something of, from, or related to the Netherlands * Dutch people () * Dutch language () Dutch may also refer to: Places * Dutch, West Virginia, a community in the United States * Pennsylvania Dutch Country People E ...

term for the Iguanidae, ''leguanen''.

Intelligence

Some species of monitors can count; studies feeding

rock monitor The rock monitor (''Varanus albigularis'') is a species of monitor lizard in the family Varanidae. The species is endemic to Central, East, and southern Africa. It is the second-longest lizard found on the continent, and the heaviest-bodied; lo ...

s varying numbers of snails showed that they can distinguish numbers up to six.King, Dennis & Green, Brian. 1999. ''Goannas: The Biology of Varanid Lizards''. University of New South Wales Press. , p. 43.Pianka, E.R.; King, D.R. and King, R.A. (2004). ''Varanoid Lizards of the World.'' Indiana University Press.

s have been observed to cooperate when foraging; one animal lures the female crocodile away from her nest, while the other opens the nest to feed on the eggs. The decoy then returns to also feed on the eggs.

s at the National Zoo in Washington, DC, recognize their keepers and seem to have distinct personalities. Two species of tree monitor in British zoos have been observed shredding leaves, apparently as a form of play.

Exploitation

As pets

Monitor lizards have become a staple in the

reptile pet Herpetoculture is the keeping of live reptiles and amphibians in captivity, whether as a hobby or as a commercial breeding operation. "Herps" is an informal term for both reptiles and amphibians, shortened from the scientific umbrella term “herpt ...

trade. The most commonly kept monitors are the

savannah monitor The savannah monitor (''Varanus exanthematicus'') is a medium-sized species of monitor lizard native to Africa. The species is known as Bosc's monitor in Europe, since French scientist Louis Bosc first described the species. It belongs to the su ...

and Ackies dwarf monitor, due to their relatively small size, low cost, and relatively calm dispositions with regular handling. Among others,

black-throated monitor The black-throated monitor (''Varanus albigularis microstictus'') is a subspecies of monitor lizard in the family Varanidae. The subspecies is native to Tanzania. Description ''Varanus albigularis microstictus'' is usually a dark gray-brown wi ...

Timor monitor ''Varanus timorensis'', the Timor monitor or spotted tree monitor, is a species of small monitor lizards native to the island of Timor and some adjacent islands. Taxonomy Kimberley rock monitors (''Varanus glauerti''), banded tree monitors (' ...

Asian water monitor The Asian water monitor (''Varanus salvator'') is a large varanid lizard native to South and Southeast Asia. It is one of the most common monitor lizards in Asia, ranging from coastal northeast India, Bangladesh, Sri Lanka, mainland Southeast A ...

mangrove monitor The mangrove monitor, mangrove goanna, or Western Pacific monitor lizard (''Varanus indicus'') is a member of the monitor lizard family with a large distribution from northern Australia and New Guinea to the Moluccas and Solomon Islands. It grows ...

emerald tree monitor The emerald tree monitor (''Varanus prasinus'') or green tree monitor, is a small to medium-sized arboreal monitor lizard. It is known for its unusual coloration, which consists of shades from green to turquoise, topped with dark, transverse d ...

black tree monitor The black tree monitor or Beccari's monitor (''Varanus beccarii)'' is a species of lizard in the family Varanidae. The species is a relatively small member of the family, growing to about in total length (including tail). ''V. beccarii'' is en ...

roughneck monitor The black rough-necked monitor (''Varanus rudicollis'') is a species of monitor lizard found in Southeast Asian countries of Thailand, Burma, and Malaysia. It is also found in Indonesia on Sumatra and islands of the Riau Archipelago It is sometim ...

s, Dumeril's monitors,

peach-throated monitor The peach-throated monitor (''Varanus jobiensis''), also known commonly as the Sepik monitor, is a species of monitor lizard in the family Varanidae. The species is native to New Guinea. Taxonomy ''Varanus jobiensis'' belongs to the subgenus ...

crocodile monitor ''Varanus salvadorii'', also known as the crocodile monitor, Papuan monitor and Salvadori's monitor, is a species of monitor lizard endemic to New Guinea. It is the largest monitor lizard known from New Guinea, and is one of the longest lizard ...

s, and

Argus monitor The yellow-spotted monitor (''Varanus panoptes''), also known as the Argus monitor, is a monitor lizard found in northern and western regions of Australia and southern New Guinea. Taxonomy The first description of the species was provided in a ...

s have been kept in captivity.

Traditional medicines

Monitor lizards are poached in some South- and Southeast Asian countries as their organs and fat is used in some

traditional medicine Traditional medicine (also known as indigenous medicine or folk medicine) comprises medical aspects of traditional knowledge that developed over generations within the folk beliefs of various societies, including indigenous peoples, before the ...

s, although there is no

scientific evidence Scientific evidence is evidence that serves to either support or counter a scientific theory or hypothesis, although scientists also use evidence in other ways, such as when applying theories to practical problems. "Discussions about empirical ev ...

as to their effectiveness. Monitor lizard meat, particularly the tongue and liver, is eaten in parts of India and Malaysia, and is supposed to be an

aphrodisiac An aphrodisiac is a substance that increases sexual desire, sexual attraction, sexual pleasure, or sexual behavior. Substances range from a variety of plants, spices, foods, and synthetic chemicals. Natural aphrodisiacs like cannabis or cocain ...

. In parts of Pakistan and southern India, as well in Northeastern India particularly Assam the different parts of monitor lizards are traditionally used for treating

rheuma Rheumatism or rheumatic disorders are conditions causing chronic pain, chronic, often intermittent pain affecting the joints or connective tissue. Rheumatism does not designate any specific disorder, but covers at least 200 different conditions, ...

tic pain, skin infections,

hemorrhoids Hemorrhoids (or haemorrhoids), also known as piles, are vascular structures in the anal canal. In their normal state, they are cushions that help with stool control. They become a disease when swollen or inflamed; the unqualified term ''hemo ...

, and the oil is used as an

lubricant (''sande ka tel''). Consuming raw blood and flesh of monitor lizards has been reported to cause

eosinophil Eosinophils, sometimes called eosinophiles or, less commonly, acidophils, are a variety of white blood cells (WBCs) and one of the immune system components responsible for combating multicellular parasites and certain infections in vertebrates. A ...

meningoencephalitis Meningoencephalitis (; from ; ; and the medical suffix ''-itis'', "inflammation"), also known as herpes meningoencephalitis, is a medical condition that simultaneously resembles both meningitis, which is an infection or inflammation of the menin ...

, as some monitors are hosts for the parasite ''

Angiostrongylus cantonensis ''Angiostrongylus cantonensis'' is a parasitic nematode (roundworm) that causes angiostrongyliasis, the most common cause of eosinophilic meningitis in Southeast Asia and the Pacific Basin. The nematode commonly resides in the pulmonary arteries ...

''.

Leather

"Large-scale exploitation" of monitor lizards is undertaken for their skins, which are described as being "of considerable utility" in the leather industry. In

Papua New Guinea Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country i ...

, monitor lizard leather is used for membranes in traditional drums (called '' kundu''), and these lizards are referred to as ''kundu palai'' or "drum lizard" in

Tok Pisin Tok Pisin (,Laurie Bauer, 2007, ''The Linguistics Student’s Handbook'', Edinburgh ; Tok Pisin ), often referred to by English speakers as "New Guinea Pidgin" or simply Pidgin, is a creole language spoken throughout Papua New Guinea. It is an ...

, the main Papuan trade language. Monitor lizard skins are prized in making the resonant part of serjas (Bodo folk sarangis) and dotaras (native strummed string instruments of Assam, Bengal and other eastern states). The leather is also used in making a

Carnatic music Carnatic music, known as or in the Dravidian languages, South Indian languages, is a system of music commonly associated with South India, including the modern Indian states of Karnataka, Andhra Pradesh, Telangana, Kerala and Tamil Nadu, an ...

percussion instrument called the ''

kanjira The kanjira, khanjira, khanjiri or ganjira, a South Indian frame drum, is an instrument of the tambourine family. As a folk and bhajan instrument, it has been used in India for many centuries. The kanjira's emergence in South Indian Carnatic m ...

''.

Food

The meat of monitor lizards is eaten by some tribes in India, Nepal, the Philippines, Australia, South Africa and West Africa as a supplemental meat source. Both meat and eggs are also eaten in Southeast Asian countries such as Vietnam and Thailand as a delicacy.

Conservation

According to

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

of threatened species, most of the monitor lizards species fall in the categories of least concern, but the population is decreasing globally. All but five species of monitor lizards are classified by the

Convention on International Trade in Endangered Species of Wild Fauna and Flora CITES (shorter name for the Convention on International Trade in Endangered Species of Wild Fauna and Flora, also known as the Washington Convention) is a multilateral treaty to protect endangered plants and animals from the threats of interna ...

under Appendix II, which is loosely defined as species that are not necessarily threatened with extinction but may become so unless trade in such species is subject to strict regulation to avoid use incompatible with the survival of the species in the wild. The remaining five species – '' V. bengalensis'', '' V. flavescens'', '' V. griseus'', '' V. komodoensis'', and '' V. nebulosus'' – are classified under CITES Appendix I, which outlaws international commercial trade in the species. The yellow monitor (''V. flavescens'') is protected in all countries in its range except Bhutan, Nepal, India, Pakistan, and Bangladesh. In

Tamil Nadu Tamil Nadu (; , TN) is a States and union territories of India, state in southern India. It is the List of states and union territories of India by area, tenth largest Indian state by area and the List of states and union territories of India ...

and all other parts of South India, catching or killing of monitor lizards is banned under the Protected Species Act.

Taxonomy

Genus ''Varanus'' :Species marked with are

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

* ''' V. bolkayi'' * ''' V. darevskii'' * ''' V. emeritus'' (=''V. salvadorii''?)'''' * ''' V. hooijeri'' * ''' V. hofmanni'' * ''' V. lungui'' * ''' V. marathonensis'' * ''' V. mokrensis'' * ''' V. pronini'' * ''' V. rusingensis'' * ''' V. semjonovi'' * ''' V. tyrasiensis'' (=''V. hofmanni''?)'''' Subgenus '' Empagusia'': Clouded monitor 2

*'' V. bengalensis'', Bengal monitor *'' V. dumerilii'', Dumeril's monitor, brown roughneck monitor *'' V. flavescens'', golden monitor, yellow monitor, short-toed monitor *'' V. nebulosus'', clouded monitor *'' V. rudicollis'', black roughneck monitor Varanidae - Varanus doreanus

Subgenus '' Euprepiosaurus'': *'' V. bennetti'', Bennett's long-tailed monitor *'' V. caerulivirens'', turquoise monitor *'' V. cerambonensis'', Ceram monitor *'' V. colei'' Kei Islands monitor *'' V. doreanus'', blue-tailed monitor *'' V. douarrha'', New Ireland monitor *'' V. finschi'', Finsch's monitor *'' V. indicus'', mangrove monitor *'' V. jobiensis'', peach-throated monitor *'' V. juxtindicus'', Rennell Island monitor *'' V. lirungensis'', Talaud mangrove monitor *'' V. melinus'', quince monitor *'' V. obor'', sago monitor *'' V. rainerguentheri'' Rainer Günther's monitor *'' V. semotus'', Mussau Island blue-tailed monitor *'' V. tsukamotoi'', Mariana monitor *'' V. yuwonoi'' black-backed mangrove monitor, tricolor monitor *'' V. zugorum'', silver monitor, Zug's monitor Varanus timorensis

Subgenus ''

'' *'' V. beccarii'', black tree monitor *'' V. boehmei'', golden-spotted tree monitor *'' V. bogerti'', Bogert's monitor *'' V. keithhornei'', canopy goanna, blue-nosed tree monitor, Nesbit River monitor *'' V. kordensis'', Biak tree monitor *'' V. macraei'', blue-spotted tree monitor *'' V. prasinus'', emerald tree monitor *'' V. reisingeri'' yellow tree monitor *'' V. telenesetes'', mysterious tree monitor, Rossell tree monitor Amneville varanus acanthurus 2708 2010

Subgenus ''

Odatria The subgenus ''Odatria'', sometimes known as the dwarf monitor lizards, consists of small monitor lizards found in Australia and Indonesia. Species in this subgenus include the smallest monitor species in the world, the tiny 16 gram Dampier Peni ...

'': *'' V. acanthurus'', spiny-tailed monitor, ridge-tailed monitor, Ackie's dwarf monitor **''V. a. acanthurus'', spiny-tailed monitor **''V. a. brachyurus'', common spiny-tailed monitor *'' V. auffenbergi'', Auffenberg's monitor, peacock monitor *'' V. brevicauda'', short-tailed monitor *'' V. bushi'', Pilbara stripe-tailed monitor, Bush's monitor *'' V. caudolineatus'', stripe-tailed monitor *'' V. citrinus'', Gulf ridge-tailed monitor *'' V. eremius'', rusty desert monitor, pygmy desert monitor *'' V. gilleni'', pygmy mulga monitor *'' V. glauerti'', Kimberley rock monitor *'' V. glebopalma'', twilight monitor, black-palmed rock monitor *'' V. hamersleyensis'', Hamersley Range rock monitor *'' V. insulanicus'', Groote Eylandt monitor **'' V. i. baritji'', black-spotted ridge-tailed monitor *'' V. kingorum'', Kings' rock monitor *'' V. mitchelli'', Mitchell's water monitor *'' V. ocreatus'', Storr's monitor *'' V. pilbarensis'', Pilbara rock monitor *'' V. primordius'' northern blunt-spined monitor *'' V. scalaris'', banded tree monitor *'' V. semiremex'' rusty monitor *'' V. similis'', Similis monitor, spotted tree monitor *'' V. sparnus'', Dampier Peninsula monitor *'' V. storri'', eastern Storr's monitor *'' V. timorensis'', Timor monitor *'' V. tristis'' **''V. t. tristis'', black-headed monitor **''V. t. orientalis'', freckled monitor Subgenus ''Papusaurus'' * '' V. salvadorii'', crocodile monitor Subgenus '' Philippinosaurus'': *'' V. bitatawa'', northern Sierra Madre forest monitor, ''butikaw'', ''bitatawa'' *'' V. mabitang'', Panay monitor, ''mabitang'' *'' V. olivaceus'', Gray's monitor, ''butaan'' Monitor lizard in Kalahari

Subgenus ''Polydaedalus'': *'' V. albigularis'', rock monitor, white-throated monitor **'' V. a. albigularis'', white-throated monitor **'' V. a. angolensis'', Angolan monitor **'' V. a. microstictus'', black-throated monitor *'' V. exanthematicus'', savannah monitor, Bosc's monitor *'' V. niloticus'', Nile monitor *'' V. stellatus'', West African Nile monitor *'' V. ornatus'', ornate monitor *'' V. yemenensis'', Yemen monitor Varanus griseus caspius

Subgenus ''Psammosaurus'': *'' V. griseus'', desert monitor **''V. g. griseus'', desert monitor, grey monitor **''V. g. caspius'', Caspian monitor **''V. g. koniecznyi'', Indian desert monitor, Thar desert monitor *'' V. nesterovi'', Nesterov's desert monitor Subgenus ''Solomonsaurus'': * '' V. spinulosus'', spiny-necked mangrove monitor, Solomon Islands spiny monitor Perentie Lizard Pair

Subgenus '' Soterosaurus'': *'' V. bangonorum'', Bangon monitor *'' V. cumingi'', Cuming's water monitor, yellow-headed water monitor *'' V. dalubhasa'', Enteng's monitor *'' V. marmoratus'', marbled water monitor, Philippine water monitor *'' V. nuchalis'' large-scaled water monitor *'' V. palawanensis'', Palawan water monitor *'' V. rasmusseni''''Varanus rasmusseni''
The Reptile Database Rasmussen's water monitor *'' V. salvator'', Asian water monitor **''V. s. salvator'', Sri Lankan water monitor **''V. s. andamanensis'', Andaman water monitor **''V. s. bivittatus'', two-striped water monitor, Javan water monitor **''V. s. macromaculatus'', Southeast Asian water monitor **''V. s. ziegleri'', Ziegler's water monitor *'' V. samarensis'', Samar water monitor *'' V. togianus'', Togian water monitor Komodo Dragon (15620549901)

Subgenus ''Varanus'': *'' V. giganteus'', perentie *'' V. gouldii'', Gould's monitor, sand monitor, sand goanna *'' V. komodoensis'', Komodo dragon *'' V. mertensi'', Mertens' monitor *'' V. panoptes'' **''V. p. panoptes'', Argus monitor **''V. p. horni'', Horn's monitor ** ''V. p. rubidus'', yellow-spotted monitor *''' V. priscus'', megalania *'' V. rosenbergi'', Rosenberg's monitor, heath monitor *'' V. spenceri'', Spencer's monitor *'' V. varius'', lace monitor

References

External links

* *
Western Australian Museum photosScientific American article
{{DEFAULTSORT:Monitor lizard Extant Miocene first appearances Taxa named by Blasius Merrem