Smallest frog leaps into limelight.

While hunting for a rare woodpecker in the Cuban rain forest, a team of biologists halted to listen to an unfamiliar chirping coming from the forest floor. Although their avian quarry eluded them, they returned with a member of what they now report is the smallest frog species in the Northern Hemisphere. Shown here at 3.5 times life size, the frog rests on a Cuban coin the size of a U.S. nickel.

"We got down on our hands and knees to find them," says S. Blair Hedges of Pennsylvania State University in State College. Hedges credits his colleague Alberto R. Estrada of the Institute of Forest Investigations in Havana with finding the first of the new species, which they informally call the eleuth frog after its genus, Eleutherodactylus. The scientists will give the species a formal Latin name in an upcoming issue of Copeia.

"This frog is probably at the limit of how small they can get," says Hedges. Less than 10 millimeters long, it shares the title of world's smallest frog with a distantly related Brazilian cousin.

The eleuth frog shows many traits typical of miniaturized species, says James Hanken of the University of Colorado at Boulder. For example, it produces only one egg at a time. Moreover, it lays its eggs out of the water and they hatch into developed frogs instead of tadpoles. "This allows tiny species to avoid predation in ponds and streams as larvae," he says.

Hedges plans to return to Cuba this summer. The island sports many other tiny species, including a bee hummingbird, the smallest bird.