The Green Lantern: Circa 2029 resembles an enormous earth whale and is depicted in the future story arc "The Last Days of Animal Man".
"The Last Days of Animal Man" is a look into the possible future of Buddy Baker, at a time when his powers as Animal Man are mysteriously fading from him. The Green Lantern of this era intervened to save Animal Man during one of these power losses. His ability to fly had deserted him, causing Animal Man to plunge 10,000 feet to his death. The Green Lantern emerged in time to rescue Animal Man , while quickly interceding to stop the villain Bloodrage from escaping from prison.
Using his power ring to cut off Bloodrage's oxygen, the Green Lantern quickly restored order; however a clearly distressed Animal Man was unable to express his thanks properly. The Green Lantern left Buddy Baker slightly insulted, and with the distinct impression that Baker was prejudicial against him for not being a fellow "primate".
It is unclear if the Green Lantern was the appointed Lantern of Sector 2814 or if he was assisting "a friend of a friend", as he called Animal Man. It is also unclear if this Lantern joined the Corps in the future depicted in the "Last Days", or if he is an active Lantern in the present day DC Universe.