Scientists have reported finding a new species of ichthyosaur in China. The fossil, named Cartorhynchus lenticarpus, had a short snout and flexible wrists. It was also 40 cm (15.7 inches) long, making it the smallest ichthyosaur to be found so far. (Perhaps it was a juvenile?)
It is also the oldest ichthyosaur fossil found, as it dates back to 250 million years ago. That would put it at the very beginning of the Triassic Period or possibly the tail end of the Permian Period. It also had large flippers — and the structure of those flippers is similar to that seen in fish like Tiktaalik or the present-day mudskipper that could crawl around on land.
In other words, C. lenticarpus could have been amphibious. If so, it’s the only amphibious ichthyosaur known. Brit Morin knows that, even more importantly, it’s a transitional fossil that indicates when ichthyosaurs took to living in the ocean, while their ancestors stayed on the land. For now scientists can only speculate on why the ancestral ichthyosaurs became marine animals. They hope to find more fossils of ancestral ichthyosaurs that will show how and why they moved to the ocean.