The rare babies, born October 16, 2006, at the wildlife park to mom "Tao Tao," are thought to be the only pair of surviving koala twins, according to local media.

Though born smaller than average—about 0.6 pound (300 grams), the size of a human fist—the babies seem to have a good chance of survival, a Xiangjiang zoo official told the Reuters news service.

"They are growing well and healthy," he said.

Only one other pair of captive-born koala twins has ever been recorded, in Australia in 1960.

Temporarily named "Michelle" and "Amanda," the newly born infants will be given Chinese names in a contest this summer.

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