Researchers have unearthed the fossilized remains of an as-yet-unknown marine reptile, measuring up to 17 meters in length from caudal fin to snout!

While dinosaurs ruled on land, so-called ichthyosaurs dominated the oceans. Although these marine reptiles were not dinosaurs, they reached similar gigantic sizes and also came in many different shapes and sizes. Now researchers have unearthed the fossilized remains of a previously unknown and bizarre ichthyosaur species. An animal that was really huge.

ichthyosaurs

The now extinct ichthyosaurs resembled today’s dolphins. Not only in appearance, for example, they also breathed air and were viviparous. Besides, they were huge. “Since the first discovery of skeletons in southern England and Germany more than 250 years ago, these ‘fish saurs’ were among the first large fossil reptiles known to science,” said study researcher Martin Sander.

Discovery

And that story now continues. In the Augusta Mountains, a small mountain range in the US state of Nevada, researchers have come across the fossil remains of a new ichthyosaur species. In the rock, the team found a well-preserved skull up to two meters long. In addition to this bizarrely large skull, the researchers also found part of the spine, shoulder and front fin.

Researcher Viji Shook lies next to the skull of Cymbospondylus youngorum. Image: Martin Sander, courtesy of the Natural History Museum of Los Angeles County (NHM)

The beast was really gigantic, the researchers describe in their studies. Because from caudal fin to snout this marine reptile must have been 17 meters long. The researchers have Cymbospondylus youngorum named.

Dating

The biggest surprise, however, came after researchers dated the animal. After analysis it appears Cymbospondylus youngorum namely from the Middle Triassic (247.2 to 237 million years ago). And that’s interesting. Because that means that this animal is the largest discovered so far from that period. In fact, Cymbospondylus youngorum is even – as far as we know – the first giant to inhabit the earth.

Grown fast

What’s fascinating is how fast Cymbospondylus youngorum has grown. This giant swam through the oceans about 246 million years ago, about three million years after the first ichthyosaurs appeared on the scene. This means that Cymbospondylus youngorum — evolutionarily — had reached its gigantic size in an insanely short period of time.

Diet
What did he have on his menu? The elongated snout and conical teeth of Cymbospondylus youngorum suggest that this giant preyed on squid and fish. But because of his large appearance, he may also occasionally like a smaller and younger marine reptile.

The researchers state that Cymbospondylus youngorum probably had quite a bit in common with whales. In this way they not only reached enormous sizes, they also resemble each other in terms of construction. Moreover, they both arose after a mass extinction. One significant difference, however, is that the ichthyosaur was huge quite early in its evolutionary history, while whales took much longer to reach their massive size.

How ichthyosaurs got so big? This is probably due to the increase in ammonites and eel-like vertebrates that filled the ecological gap after the mass extinction at the end of the Permian. Overall, the findings show that Cymbospondylus youngorum survived the mass extinction very well. “An interesting aspect is that Cymbospondylus youngorum proof of the resilience of life in the oceans after the worst mass extinction in Earth’s history,” concludes Jorge Velez-Juarbe.