Beautiful New See-Through Frog Puts Whole Heart on Display

The new-to-science Amazonian glassfrog has skin so transparent that its tiny heart can be seen beating in its chest.

The Amazon rain forest is obviously a magical place, made even more so by the spectacular creatures that make it their home. It's as if Mother Nature and Dr. Seuss got together and set up a test kitchen there to create an impossible assortment of wonderful organisms. We're talking caterpillars that look exactly like snakes, a fungus that eats plastic, and cute little treehoppers straight out of Pokémon, for starters.

And now the latest wonder to be discovered there is a new species of glassfrog, one that has nothing to hide.

L. A. Coloma/CC BY 4.0

Glassfrogs are inherently remarkable, what with their transparent skin that covers their bellies and reveals their organs underneath. Imagine if we had that? Medical diagnosis and understanding digestion woes would be so much easier! This new species, however, from Amazonian Ecuador takes it a step further by fully exposing its heart thanks to the transparent skin stretching all across its underside. It is also unique for its singular spotted pattern as well as a long, signature call.

Discovered by a team of scientists led by Dr. Juan M. Guayasamin from Universidad San Francisco de Quito, the description of the new frog, "A marvelous new glassfrog (Centrolenidae, Hyalinobatrachium) from Amazonian Ecuador," is published in the open access journal ZooKeys. In it, the authors note:

"The new species, Hyalinobatrachium yaku sp. n., is differentiated from all other congenerics by having small, middorsal, dark green spots on the head and dorsum, a transparent pericardium, and a tonal call that lasts 0.27–0.4 s, with a dominant frequency of 5219.3–5329.6 Hz."

Ross Maynard/CC BY 4.0

The frogs were found in several locations; the variety of those places and the distance apart has led the scientists to speculate that the new species has a broader distribution, including areas in neighboring Peru. Though they aren't sure, noting:

"The uncertainty about its distributional range comes from a number of reasons. Firstly, the species' tiny size of about 2 cm makes it tough to spot from underneath the leaves. Then, even if specimens of the species have been previously collected, they would be almost impossible to identify from museum collection, as many of the characteristic traits, such as the dark green marks, are getting lost after preservation."

The species name yaku is the Kichwa word for water. Water is essential for glassfrogs' reproduction; and could also be their undoing. "Water pollution, mainly through oil and mining activities," the authors write, "represents one of the biggest threats for Amazonian amphibians, as well as for numerous other water-dependent species."

Mother Nature would not be pleased.