An endangered 21-year-old lemur is missing, and may have been stolen, from the San Francisco Zoo on Tuesday night, according to officials.

The ring-tailed lemur named Maki is among the oldest of the primates housed in the zoo's Lipman Family Lemur Forest, which is home to seven different species of lemurs.

San Francisco Police Department officers, who responded to a report of a burglary, say Maki was last seen in his enclosure on Tuesday. They are investigating a possible break-in at the habitat and are calling on the public to help with any information leading to the animal's whereabouts.

"We understand that lemurs are adorable animals, but Maki is a highly endangered animal that requires special care. We are asking the public for help in his return," said Dr. Jason Watters, Executive Vice President of Animal Behavior and Wellness at the zoo, ABC 7 reported.

"As one of our oldest lemurs, Maki requires a specialized diet. Of the 19 lemurs here, at 21.5 years, he has exceeded median life expectancy of 16.7 years, but is also one of the slowest, and we believe, likely, the easiest to catch."

The ring-tailed species is among the best known and most easily recognized, according to the zoo's web site, which states that the enclosure is the largest outdoor lemur habitat in North America.

"At the Zoo on a sunny day, you can often see the ring-tailed lemurs catching some rays from the sun in a yoga-like sitting position. They sit with their arms outstretched and heads back to maximize sun exposure," the site says.

Lemurs are banned as pets in the state of California.

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