Thai National Parks

Reptiles of Thailand

Species of Thailand

Roughneck monitor

Thai: เห่าช้าง, hao chang

Binomial name: Varanus rudicollis, John Edward Gray, 1845

The black roughneck monitor lizard, 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 Rhio Archipelago It is sometimes known simply as the roughneck monitor lizard.

The habitat of Varanus rudicollis is limited to primary and secondary rainforest and mangrove swamps. In the wild the black roughneck monitor is very rarely seen, but whether this is because of its rarity or its very secretive behavior is uncertain. They are often kept successfully in captivity, but have a shy disposition.


The roughneck is a medium to large monitor. It usually reaches an average adult size of 3–4 ft. (90–120 cm), with a maximum length of 5 cm, reported. The rough-necked monitor can be easily recognised by large pointed scales adorning the necks of adults.

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Scientific classification

Varanus rudicollis

Common names

  • German: Rauhnackenwaran
  • English: Roughneck monitor
  • Thai:
    • เห่าช้าง, hao chang
    • คอรั้ง
    • คอลั้ง, kor lung
    • เห่าดง, hao dong


  • Varanus (Empagusia) rudicollis, André Koch et al. (2013)
  • Varanus rudicollis, Larry Lee Grismer (2011)
  • Varanus rudicollis, Ulrich Manthey & Wolfgang Grossmann (1997)
  • Varanus (Empagusia) rudicollis, Thomas Ziegler & Wolfgang Böhme (1997)
  • Varanus rudicollis, H.F. De Lisle (1996)
  • Varanus rudicollis, Edward Harrison Taylor (1963)
  • Varanus swarti, Mangili (1962)
  • Varanus (Varanus) salvator scutigerulus, Robert Mertens (1942)
  • Varanus (Dendrovaranus) rudicollis, Robert Mertens (1942)
  • Varanus scutigerulus, Thomas Barbour (1932)
  • Varanus rudicollis, Nelly de Rooij (1915)
  • Varanus rudicollis, George Albert Boulenger (1885)
  • Uaranus sic rudicollis, John Edward Gray (1845)

No photo for this species yet

Distribution map of Roughneck monitor, Varanus rudicollis in Thailand

Range map of Varanus rudicollis in Thailand

Important note; our range maps are based on limited data we have collected. The data is not necessarily accurate or complete.

Special thanks to Ton Smits, Parinya Pawangkhanant, Ian Dugdale and many others for their contribution for range data.

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