Masai, a tawny old lioness who blinked in the sun, bared her teeth at other lions and became one of Zoo Atlanta's star attractions, has died.

The African lioness died about 9:30 a.m. in a holding area at the zoo while workers gathered and wept.

She was 18, "a pretty old girl," said Lori Perkins, the zoo's director of animal programs .

Officials think Masai succumbed to upper respiratory problems and anemia. A veterinarian who diagnosed her condition earlier this year called it "life threatening."

The lioness responded to treatment, said Perkins, but never fully recovered. "I think that her decline has been a slow decline," Perkins said.

Tuesday morning, when it became clear the old cat was about to breathe her last, zoo workers gathered to await her last moments. Masai's breathing slowed, then stopped. Her chest was still.

Word spread: Masai was dead.

"As is usuallly the case, we had a little ceremony for her," said Perkins.

Masai was born June 3, 1990, at a wildlife orphanage in the land of her species — Zimbabwe, Africa. Later that year, she came to the Riverbanks Zoo in Columbia, S.C., where she bore three cubs. She came to Zoo Atlanta in October 2003 as part of the zoo's African Plains exhibit.

Masai settled in, and made one thing clear, said Perkins: She liked her personal space. If fellow lion Farasi stuck his shaggy head in her face, for example, she was liable to swat him on the snoot.

"Masai's personality was irreplaceable," said Perkins. "She was a very spirited cat."

The zoo does not plan to replace the lioness with another. Kiki, a younger lioness, recently gave birth to three cubs. With three adults and a trio of youngsters, the zoo has plenty of Panthera leo.

"With three boys, we have a house full of lions," Perkins said.

Veterinarians at the University of Georgia will perform a necropsy on the 400-pound cat. Those results should be available within a month.