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 sometimes known simply as the roughneck monitor. In Thailand is called h̄èā cĥāng (Thai: เห่าช้าง; "elephant bark/roar").

The habitat of Varanus rudicollis is limited to primary and secondary rainforest and mangrove swamps. In the wild the black rough-necked 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.

This species is most closely related to its sister group, the water monitor species complex (e.g., the Asian water monitor) which are also in the subgenus Soterosaurus, having split from them 14 million years ago in the middle Miocene.

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