A new ancestor of amphibians has been discovered, which lived 270 million years ago and was called Kermitops gratus in honor of the frog Kermit from the Muppets: its fossil skull is in fact equipped with large oval-shaped eye sockets which recall the wide eyes of the famous puppet created by Jim Henson in 1955. The identikit of the new species, useful for reconstructing the evolutionary tree of modern amphibians, is published in the Zoological Journal of the Linnean Society by researchers from Washington University and the Field Museum of Natural History in Chicago.
The fossil skull, just over two centimeters long, was found in 1984 by paleontologist Nicholas Hotton during an excavation in Texas.
The remains of ancient reptiles, amphibians and ancestors of modern mammals have been found among the red sedimentary rocks known as 'Red Beds', which date back to the Lower Permian age.
Many of the fossils collected then remained deposited in the Smithsonian collection awaiting more in-depth studies.
This was also the case for the skull of Kermitops gratus, re-examined only in 2021. The researchers were struck by its particular mix of traits that make it different from the most ancient tetrapods, the ancestors of amphibians and other modern four-legged vertebrates.
The region of the skull behind the eyes, for example, was much shorter than the elongated, curved snout.
These proportions helped the animal (which probably resembled a somewhat stocky salamander) to capture small larvae-like insects.
The researchers identified the fossil as belonging to the temnospondyl group, primitive relatives of amphibians that lived for over 200 million years from the Carboniferous to the Triassic.
However, considering that the animal's skull presented unique characteristics, the scholars established that it belonged to a completely new genus which they called Kermitops, a name that derives from Kermit, the Muppets puppet, combined with the Greek suffix '-ops', which means face.
The term gratus which identifies the species was instead chosen to underline the researchers' gratitude towards the paleontologists who originally found the fossil.
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