A very well preserved fossil of a now-extinct turtle species was found by paleontologists in Madagascar. The newly discovered species, which has been named Sahonachelys mailakavava (meaning “quick-mouthed frog turtle” in the Malagasy language), lived during the Cretaceous Period.
The paleontologists were quite surprised to find the almost-complete turtle skeleton as they were initially searching for dinosaur and crocodile bones. In an interview with Live Science, Walter Joyce, who is a paleontologist at the University of Fribourg in Switzerland and the lead author of the study, described the remains, “The specimen is absolutely beautiful and certainly one of the best-preserved late Cretaceous turtles known from all southern continents,” adding that it is “an exceptionally rare find”.
While it’s unclear as to when it first appeared on Earth as well as when or why it became extinct, Joyce said that it “likely survived the big extinction event that killed the dinosaurs” about 66 million years ago.
This odd-looking turtle had a face similar to a frog and feasted on its prey by sucking them into its mouth along with water. The freshwater species had a flat skull, a rounded mouth, big tongue bones, and had a shell that measured approximately 10 inches long.
As for its suction characteristic, Joyce explained it in further detail, “This is a specialized mode of underwater feeding, during which the animal quickly opens its mouth and expands its throat to quasi-inhale a large volume of water, including the desired prey item.” They would have feasted on tadpoles, fish larvae, and plankton, among other things.
The history of the Sahonachelys mailakavava is quite interesting as they were part of the Pelomedusoidea family that includes today’s species of Madagascan and South American river turtles. It is believed that the Sahonachelys mailakavava was the first ever Pelomedusoid that evolved the suction feeder “to such an extreme”.
There are several species of modern turtles that do suction feed and the majority of them are part of the Chelidae family. As a matter of fact, when Joyce first viewed the skull, his initial reaction was that it was a Chelid, but the shell revealed that it was instead a Pelomedusoid. Even though Chelids and Pelomedusoids are distant relatives, they both evolved the ability to suction feed separate from each other. “It highlights that distantly related animals will converge upon the same shape when adapting to similar lifestyles,” he noted.
An image of what the Sahonachelys mailakavava would have looked like and a photo of the skull bones can be seen here.
The study was published in the journal Royal Society Open Science where it can be read in full.