CLEVELAND, Ohio -- A local graduate student and her husband have found a shape-shifting frog in Ecuador that changes its skin texture from spikey to smooth in mere minutes.
It is believed to be the first vertebrate identified that can do that, said Katherine Krynak, who is working toward a PhD in biology at Case Western Reserve University.
The new critter is called Pristimantis mutabilis (mutable rain frog) but Katherine and Tim Krynak call it punk rocker frog because of the spiked texture that it can present.
Tim, a project manager with the Cleveland Metroparks, said they first encountered the marble-sized amphibian in 2006 when they walked the trails of the Andean cloud forest in Ecuador.
"We were trying to document species of amphibians and saw the frog sitting on a moss-covered leaf," Tim said. "We took a photo of the small frog, but it wasn't until the photograph was enlarged on the computer that we could tell this frog was very different."
On a 2009 trip, they found what appeared to be the same species. "Katherine grabbed it and put it in a cup with a lid so we could take a picture later," he said.
At the field station, Tim looked at the captive frog through his camera and said "Katherine, that's not our frog, this frog has smooth skin."
But when they placed the frog in moss, the spiney skin texture returned. To document the phenomenon, they took the rough-skinned frog and put it on a smooth white surface to photograph. Its skin became smooth again, in three to five minutes.
Both said it is too early to tell whether the shape shifting is a defense mechanism. Anything could trigger it, including something in the environment that humans cannot perceive.
The Krynaks are part of a team describing the discovery in an article in the Zoological Journal of the Linnean Society that is scheduled for publication this week.
The primary author is Juan M. Guayasamin, of the Universidad Tecnologica Indoamerica, Ecuador. He used genetic and morphological analyses to establish that P. mutabilis was a unique species that had never been described in the scientific literature.
Co-author Carl R. Hutter, of the University of Kansas, studied the frog's calls, noting three songs that differentiate it from other species.
In 2011, Hutter found a frog while looking for P. mutabilis. He joined Guayasamin, and co-author Jaime Culebras on research establishing that his frog was a relative of the Krynaks' frog called Pristimantis sobetes that also can alter its skin texture. The unique shape-changing ability of both species is supposed to be described for the first time today.
The Krynaks said that aspects of the discovery illustrate the importance of using multiple techniques to describe new species.
Taxonomy, the science of classifying all living things, has traditionally relied on appearance to differentiate life forms, establishing eight major ranks that include species, genus, family, order and class.
Color, shape and size have always been important taxonomic criteria.
But what would have happened if the only known example of P. mutabilis had been preserved and this unique shape-shifting ability not noted?
"Behavioral observation is very important for new species descriptions and the creation of field guides, but is not always possible. Amphibians are declining so rapidly that scientists are now often limited to describing new species from museum specimens because the animals have recently gone extinct in the wild." Katherine Krynak said.
Researchers still need to establish the size of the P. mutabilis population and how many other species share the shape-shifting ability.
Katherine Krynak said the new species also bolsters the argument for preserving habitat.
As it happens, the frogs the Krynaks saw in the wild were on a private 1,000-acre reserve owned by Dr. Jane Lyons, a conservationist with an expertise in birds.
But nations, especially less developed ones like Ecuador, want to establish better economic conditions and struggle with the tensions between conservation and development, they said.
Locals near Lyons' reserve enjoy diverse economic benefits by working there, Tim Krynak said. Eco tour guiding and the jobs associated with the business provide opportunities for economic growth and also depend upon the protection of habitat.
The preserve is called Reserva Las Gralarias, Katherine said, noting that she and Tim work for a private, nonprofit foundation in Ohio to support it.
While the Cleveland Metroparks supports conservation efforts around the world, the Krynaks' research in Ecuador is independent.