His name was Angalifu. He was 44 years old. And a popular attraction at the San Diego Zoo Safari Park.
But the elderly northern white rhino died on Sunday, bringing the species closer to extinction.
There are now only five of them left worldwide.
The male rhino was under veterinary care for a number of age-related conditions.
The only five to remain are an elderly female at the San Diego Zoo Safari Park, one at a zoo in Europe, and three in Africa.
Northern white rhinos have been brought to the brink of extinction due to poaching.
The few that have been preserved at zoos have been largely non-reproductive.