Researchers lift a female Yangtze giant softshell turtle out of the water at a zoo in Suzhou in eastern China's Jiangsu province on April 7, 2016. The only known female member of one of the world's rarest turtle species died at the zoo on Saturday, April 13, 2019.

(Chinatopix via AP)

At a Glance

The 90-year-old female was one of only four Yangtze giant softshell turtles left on the planet. It died after an attempt at artificial insemination. A 100-year-old male remains at the Suzhou Zoo.The gender of two other turtles in Vietnam is not known.

The death of a 90-year-old female Yangtze giant softshell turtle on Saturday leaves only three of the world's rarest turtles.

The turtle died at the Suzhou Zoo in East China's Jiangsu province , the China Daily reported. Researchers spent hours trying to revive the turtle, the report said.

One of the three remaining Yangtze giant softshell turtles, a male, also lives at the Suzhou Zoo. It is thought to be more than 100 years old.

The other two live in the wild in lakes outside of Hanoi, Vietnam, according to China Daily. Their genders are not known.

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Suzhou Zoo had tried unsuccessfully for years to get their pair of turtles to mate and reproduce naturally. The artificial insemination on Friday was the fifth time the zoo had tried the procedure with the pair.

Experts collected the turtle’s ovarian tissue for future research, the Associated Press reported. A necropsy will be performed as well.

At 39 inches long and weighing up to 220 pounds, the Yangtze giant softshell turtle (Rafetus swinhoei) is the , according to AFP.