The Komodo dragon, also known as the Komodo monitor, is a large species of lizard found in the Indonesian islands of Komodo, Rinca, Flores, Gili Motang and Padar. A member of the monitor lizard family (Varanidae), it is the largest living species of lizard, growing to a maximum length of 3 meters (10 ft) in rare cases and weighing up to around 70 kilograms (150 lb). Their unusual size has been attributed to island gigantism, since there are no other carnivorous animals to fill the niche on the islands where they live. (information from Wikipedia)
This monitor was spotted at National Zoo in Washington, D.C..