 The blue iguana ( Cyclura lewisi ) , also known as the Grand Cayman iguana , Grand Cayman blue iguana or Cayman Island blue iguana , is an endangered species of lizard endemic to the island of Grand Cayman . Previously listed as a subspecies of the Cuban iguana ( Cyclura nubila ) , it was reclassified as a separate species in 2004 because of genetic differences discovered four years earlier . The blue iguana is one of the longest @-@ living species of lizard ( possibly up to 69 years ) . The record is 67 years . 
