New lizard ties for ‘world’s smallest’

A newly discovered species joins a close relative in sharing the title of world’s smallest lizard. Sixteen millimeters long from the tip of its snout to the base of its tail, the new species, Sphaerodactylus ariasae, darts through moist leaf litter in a small area of the Dominican Republic. Its discoverers, S. Blair Hedges of Pennsylvania State University in State College and Richard Thomas of the University of Puerto Rico in San Juan, proclaim their new find to be a sister species of the tiny Sphaerodactylus parthenopion that Thomas found in the British Virgin Islands in 1965.

Hedges

When it comes to length, “they’re in a dead heat,” says Hedges. He and Thomas found the new lizard on the southernmost tip of Hispaniola and on nearby Beata Island.

Biologists have explored the region for decades, but no one had recorded tiny lizards there. Even familiar places still hold biological surprises, says Hedges.

The new species belongs to a group of lizards that lay a single egg at a time. In their Lilliputian context, that egg is huge, almost the width of the mother’s body. It hatches into a baby lizard about three-quarters the size of an adult.

The researchers describe their find in the December Caribbean Journal of Science.

Hedges has found dozens of new species in the Caribbean. In Cuba, he discovered a frog that ties for the world’s smallest. “People probably think I have a little box in the lab that shrinks animals,” he says.

Susan Milius is the life sciences writer, covering organismal biology and evolution, and has a special passion for plants, fungi and invertebrates. She studied biology and English literature.