Monitor lizard

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Monitor lizards
An Australian lace monitor (Varanus varius) on a tree.
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Sauropsida Order: Squamata Suborder: Sauria Family: Varanidae Genus: Varanus Merrem, 1820
Species
Many, see text.

Monitor lizards are the family Varanidae, a group of lizards which includes the largest living lizard, the Komodo Dragon. Varanidae contains only a single genus: Varanus.

In Australia monitor lizards are known as goannas (See main article).

Contents 1 Evolutionary overview 2 Origin of the name 3 Apparent intelligence 4 Classification 5 Trivia 6 References

[edit] Evolutionary overview

Monitor lizards are considered to be the most derived lizards, possessing a relatively high metabolic rate for reptiles and several sensory adaptations that benefit the hunting of live prey. Recent work indicates that the Varanid lizards, including the Komodo dragon, do indeed have venom.^[1] The bleeding, swelling, and infection from varanid bites are therefore not solely due to strains of bacteria in their mouths, as previously believed. Some monitor lizards are apparently capable of parthenogenesis.^[2]

[edit] Origin of the name

The genus name, "Varanus" is derived from the Arabic word waral ورل, which is translated to English as "monitor". It has been suggested that the occasional habit of varanids to stand on their two hind legs and to appear to "monitor" their surroundings led to the original Arabic name.^[3] According to legend, these lizards were supposed to warn people that crocodiles were nearby.^[4]

[edit] Apparent intelligence

Varanid lizards are very intelligent, and some species can even count. Careful studies feeding V. albigularis at the San Diego Zoo varying numbers of snails showed that they can distinguish numbers up to six.^[5][4][6] V. niloticus have been observed to cooperate when foraging. One varanid 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.^[7][4] Komodo dragons, V. komodoensis, at the Smithsonian National Zoological Park in Washington, D.C., recognize their keepers and seem to have distinct personalities.^[4]

[edit] Classification

Genus Varanus

• Varanus acanthurus: Spiny-tailed goanna, Northwestern Ridge-tailed monitor, or "ackie"
  • Varanus acanthurus brachyurus, Common Ridge-tailed Monitor, or Yellow Ackie
  • Varanus acanthurus insulanicus or Island Ridge-tailed Monitor
• Varanus albigularis White-throated monitor or Albig
  • Varanus albigularis albigularis
  • Varanus albigularis angolensis
  • Varanus albigularis ionidesi Black-throated Monitor or Ionide
• Varanus auffenbergi Peacock monitor
• Varanus baritji Northern ridge-tailed goanna
• Varanus beccarii Black tree monitor
• Varanus bengalensis Bengal monitor or the Common Indian Monitor
• Varanus bogerti Louisiade tree monitor
• Varanus brevicauda Short-tailed monitor
• Varanus bushi
• Varanus caerulivirens Blue pin-spot monitor
• Varanus caudolineatus Stripe-tailed goanna
• Varanus cerambonensis Ceram mangrove monitor
• Varanus doreanus Blue-tailed monitor
• Varanus dumerilii Dumeril monitor aka Brown Rough Neck Monitor
• Varanus eremius Desert pygmy monitor
• Varanus exanthematicus: Savannah monitor
• Varanus finschi Finsch's monitor
• Varanus flavescens: Yellow mangrove monitor
• Varanus giganteus: the Perentie
• Varanus gilleni Pygmy mulga goanna
• Varanus glauerti Kimberley rock monitor
• Varanus glebopalma Black-palmed rock monitor
• Varanus gouldii Sand goanna (also Gould's goanna, or Ground goanna)
• Varanus griseus Desert monitor
• Varanus indicus Mangrove monitor
• Varanus jobiensis Peach-throat monitor
• Varanus juxtindicus Hakoi
• Varanus keithhornei Canopy goanna
• Varanus kingorum King's goanna
• Varanus komodoensis: Komodo dragon
• Varanus mabitang Panay monitor
• Varanus macraei Blue tree monitor
• Varanus melinus Quince monitor
• Varanus mertensi: Mertens' water monitor
• Varanus mitchelli Mitchell's water monitor
• Varanus nebulosus Clouded monitor
• Varanus niloticus: Nile monitor
• Varanus olivaceus Gray's monitor, Butaan
• Varanus ornatus Ornate monitor
• Varanus panoptes Argus monitor, Yellow-spotted goanna, Floodplain goanna
• Varanus pilbarensis Pilbara rock monitor
• Varanus prasinus: Emerald tree monitor
  

  

  Emerald tree monitor (also called Green tree monitor) lizard Varanus prasinus
• Varanus primordius Blunt-spined goanna
• Varanus prisca: Megalania (extinct)
• Varanus rosenbergi Rosenberg's goanna
• Varanus rudicollis: Black Roughneck monitor
• Varanus salvadorii: Crocodile monitor, Artrelia
• Varanus salvator: Water monitor
• Varanus scalaris Spotted tree goanna
• Varanus semiremex Mangrove pygmy goanna
• Varanus spenceri Spencer's goanna
• Varanus spinulosus St. Isabel mangrove monitor
• Varanus storri Storr's goanna
• Varanus telenesetes Lia (Biri), Rossel Island tree monitor
• Varanus timorensis: Timor tree monitor or Timor monitor
• Varanus tristis Black-headed tree goanna
• Varanus varius: Lace monitor
• Varanus yemenensis Yemen monitor
• Varanus yuwonoi Tricolor monitor

[edit] Trivia

• The movie monster Varan takes its name from this genus.
• In a season 4 episode of Hey Arnold, the character Helga owned a monitor lizard.
• In My Gym Partner's a Monkey, one of the hall monitors is a monitor lizard.
• The Freshman starring Matthew Broderick, is based on the delivery of and cooking of a komodo dragon

[edit] References