The giant tortoise Lonesome George has been found dead, officials at the Galapagos National Park have said.
George, believed to be the last of his subspecies, was known as one of the rarest animals in the world. The tortoise was thought to be around 100 years old.
His failed efforts to produce offspring made him a symbol of disappearing species.
Edwin Naula, the head of the Galapagos National Park in the Galapagos Islands, Ecuador told Reuters "his life cycle came to an end."
"This morning the park ranger in charge of looking after the tortoises found Lonesome George, his body was motionless.”
He was found in 1972, and scientists had been trying to get him to mate since 1993.
Charles Darwin used the differences in appearance between tortoises in the Galapagos Islands to help formulate his theory of evolution.
The cause of George’s death is unknown. Officials at Galapagos National Park said they may embalm his body to show "we must be more responsible keeping the environment in which we live, our planet.”