The first birth of a red ruffed lemur at the San Diego Zoo in 13 years took place last month, the park reported Wednesday.
The male born May 18 now weighs 6.6 ounces, and gains an average of around 10 grams a day.
The zoo said the unnamed lemur was born to Morticia, a first-time mother, and lets keepers take him out for daily weigh-ins in exchange for fruit. The zoo's lemurs are currently off-exhibit while the new Africa Rocks attraction is built.
Despite the recent lemur birth drought, more than 100 have been born at the zoo since 1965.
The species, found in the wild only in the Masoala Peninsula in Madagascar, is listed as critically endangered by the International Union for Conservation of Nature.
The zoo also announced that a Tasmanian devil named Nick was released back into his exhibit at the Conrad Prebys Australian Outback Wednesday, almost three weeks after being given a pacemaker.
Nick was found to have an abnormal heart rhythm during a routine veterinary examination in January, and further testing confirmed that he had a heart disease that caused his heart to beat slowly. The device was placed in his abdomen, with an electrode sutured to the heart -- only the second time the procedure has been performed on this type of animal, according to the zoo.
The IUCN lists the animals as endangered. Their main health problem is not heart disease, but a fatal form of cancer that has ravaged their population on the island of Tasmania, off Australia.