Granddad, an Australian lungfish that was the longest-living fish in any aquarium in the world, was euthanized Sunday because of complications from old age, the Shedd Aquarium announced Monday.

He’d been at the Chicago museum since the Century of Progress World’s Fair in 1933.

“It is incredible to know that over 104 million guests had the opportunity to see Granddad in our care and learn about his unique species over eight decades,” said Bridge Coughlin, Shedd’s president and CEO. “For a fish who spent much of his time imitating a fallen log, he sparked curiosity, excitement and wonder among guests of all ages who would hear his story and learn about the incredible biology that makes his species a living fossil and one of the oldest living vertebrate genera on the planet.”

A call to Chicago’s Australian consulate resulted in sadness and surprise. “What? Granddad?” said a staffer at the consulate. “Oh my god. You made me sad now.”

Australian officials participated in a Shedd birthday party for Granddad. The consular staffer noted Granddad was at “full maturity” when he arrived at the Shedd in 1933, and said he was estimated to be more than 100 years old.