Selat the Komodo dragon lived a long life, by Komodo dragon standards.

The 150-pound geriatric reptile lived almost 19 of his 20 years at the Woodland Park Zoo, where he was euthanized Tuesday due to osteoarthritis and joint deterioration. He was in the top 10th percentile of oldest Komodo dragons in the North American population.

The Woodland Park Zoo had been working with SOUND Veterinary Rehabilitation Center to care for Selat as his age-related health issues worsened.

Selat’s health-management plan included laser treatments and massage therapy, which he received with a calmness that belied his species’ reputation, according to a Seattle Times story that detailed his treatment.

Selat continued to receive veterinary attention until the end, but caretakers said his condition deteriorated rapidly in recent days.

“The quality of Selat’s life was compromised, so we made the humane decision to euthanize him,” the zoo said.