The Nile monitor (Varanus niloticus) is a large member of the monitor lizard family (Varanidae) found throughout much of Africa, but is absent from the west, where it is replaced by Varanus stellatus. Other common names include the African small-grain lizard, water leguaan or river leguaan (leguan, leguaan, and likkewaan mean monitor lizard in South African English, and can be used interchangeably).