A green sea turtle that has delighted visitors to the New England Aquarium in Boston for more than 50 years has passed her latest physical checkup.

Veterinarians performed Myrtle’s checkup after the 500-pound reptile was hoisted from the aquarium’s Giant Ocean Tank in an enormous crate on a chain.

Myrtle is thought to be up to 95 years old, which would place her just beyond the upper boundaries of the species’ longevity. But the big turtle is “in robust condition” despite her advance age, said Mike O’Neill, manager of the ocean tank.

Sea Turtle Medical Exam
The massive sea turtle rests in a crate after being hoisted out of a huge ocean tank (Rodrique Ngowi/AP)

There is every reason to believe Myrtle will stick around for years to come, Mr O’Neill said.

“She is iconic,” he said. “One of the really special things we see is parents with their kids who say, ‘This is Myrtle, she has been here since when I was a kid’. She has this multigenerational impact which is really special.”

Giving the massive sea turtle a physical examination is no small feat, and happens about twice a year.

First, divers shepherd Myrtle into the underwater crate. Next, a team of vets and aquarists work together to draw blood from Myrtle, check her flippers for range of motion and make sure her eyes, mouth and nose are in working order.

She then receives an ultrasound, her weight is taken and she returns to the ocean tank, Mr O’Neill said.

Myrtle has been visited by some 50 million people over the decades and has become used to humans in that time. The aquarium’s website boasts that Myrtle, who arrived from another aquarium in 1970, “loves having her shell scratched”.

Sea Turtle Medical Exam
New England Aquarium staff examine Myrtle (Rodrique Ngowi/AP)

Green sea turtles are the second-largest species of sea turtle, and they live in tropical and subtropical oceans around the world. The International Union for Conservation of Nature lists them as endangered and decreasing in population.

Myrtle shares space with a pair of loggerhead sea turtles named Carolina and Retread who are about half her age and size. The aquatic roommates also received physicals on Tuesday and are “also both doing great”, Mr O’Neill said.