Bornean flat-headed frog

The Bornean flat-headed frog (Barbourula kalimantanensis) is a species of frog in the family Bombinatoridae. For many years, it was thought to be the only frog with no lungs. However, micro CT scanning revealed that, like all other known frog species, the Bornean flat-headed frog has lungs, though they are tiny.

Djoko Iskandar, an Indonesian zoologist, first described the Bornean flat-headed frog based on a single specimen. However, he did not think the frog was lungless until he was in the field with David Bickford's expedition. Bickford et al. dissected some of the specimens and were unable to see the lungs, leading them to incorrectly conclude that no lungs were present.