Seven New Diamond Frog Species Found Hiding in Madagascar's Leaf Litter

An international team of researchers has identified seven previously undescribed species of Madagascar's diamond frogs (Rhombophryne), adding evidence that this secretive amphibian group is far more diverse than scientists had realized. The researchers combined field observations, museum specimens and DNA analysis to sort out the frogs' identities and resolve a taxonomic problem that had remained unsettled for years.

"Diamond frogs have been hiding their diversity beneath our feet," said Dr. Mark D. Scherz, curator of herpetology at the Natural History Museum Denmark and lead author of the study. "Many species spend most of their lives beneath the leaf litter, and even when they emerge they can look deceptively similar."

Diamond frogs are among Madagascar's most distinctive amphibians: some are extremely round and resemble rain frogs found in mainland Africa, spending much of their time hidden beneath the forest floor, while others have long legs and live among moss. Most look brown at first, but several species carry vivid markings, including bright orange flashes or bold white and black patterns, that stay hidden until the frogs move; researchers think these markings may help startle predators.

The research effort began more than 12 years ago, when scientists repeatedly encountered frogs that appeared to represent undescribed species but were difficult to identify because older species names did not clearly match the genetic lineages found in modern specimens. A breakthrough came from museomics, the sequencing of DNA from historical museum specimens, including original type specimens, which researchers compared with DNA from newly collected frogs alongside external features, skeletal anatomy and frog calls.

"Museum collections are far more than archives of the past - they are essential scientific resources for understanding biodiversity today," said Dr. Alice Petzold of the University of Potsdam, who led the museomics work. The study was carried out through cooperation among scientists and institutions in Madagascar and Europe, in forests that are becoming increasingly fragmented by deforestation.