Rare Frogs Give Birth to Live Tadpoles

Photo

A male, left, and female of Limnonectes larvaepartus, a species that was discovered in the rain forests of Indonesia’s Sulawesi Island. Credit Jimmy A. McGuire 

A tiny frog discovered in the rain forests of Indonesia’s Sulawesi Island is the only frog known to give birth to live tadpoles.

Of the roughly 6,000 frogs known in the world, about a dozen species fertilize their eggs internally. A handful give birth to froglets, and a few lay fertilized eggs.

The newly described frog, named Limnonectes larvaepartus, was first discovered in 1998 by Djoko Iskandar, a zoologist at the Bandung Institute of Technology in Indonesia. The frog weighs just two-tenths of an ounce, or about as much as a nickel. At the time, Dr. Iskandar noticed that the frogs appeared to be laying tadpoles, but he was not able to identify the species. “We now have a lot of museum specimens to help identify coloration, texture and webbing,” said Jimmy A. McGuire, a herpetologist at the University of California, Berkeley, and a co-author, with Dr. Iskandar and Ben J. Evans, of a paper describing the frog in the journal PLOS One.

The frog belongs to a group known as fanged frogs because of two projections from their lower jaws used for fighting. Although the researchers know of at least 15 other species of fanged frogs on Sulawesi, Limnonectes larvaepartus is only the fourth to be formally described.

“It wasn’t until we could use molecular data that we could start to sort these frogs into piles,” Dr. McGuire said.