Recent surveys show that this rare and poorly studied small fat-tailed mouse opossum is concentrated in the Cerrado savannas. Scientists were surprised, since it was previously described from the Caatinga, a dry forest region in northeastern Brazil.

"It is actually a Cerrado species," Conservation International biologist Cristiano Nogueira said.

The body of the opossum is about three inches (eight centimeters) long. It packs on fat in its tail each rainy season to burn when food is scarce in the dry season.

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