One of the most famous species of marine reptiles is the icthyosaurs. With that said, not all early icthyosaurs resembled fish or dolphins. In fact, one species called Cymbospondylus resembled a mosasaur. This giant creature patrolled the Triassic seas, being one of the largest sea reptiles of the time.

Basic info

Meaning of name: Cymbospondylus means "boat vertebrae".

Time of existence: Cymbospondylus lived in the early Triassic, 252.17 million to 237 million years ago.

Diet: Despite it's massive size, Cymbospondylus' jaws weren't really that strong, and therefore it didn't hunt animals much bigger than it. It mostly ate fish, but possibly ate Tanystropheus tails. It possibly even attacked living Tanystropheus, although not much evidence supports this.

Threats: Cymbospondylus wasn't a viable prey option for the majority of animals in the Triassic seas, so it didn't really have anything to fear.

Size: Cymbospondylus was anywhere from 20 to 33 feet long.

Attributes: Cymbospondylus had two major attributes: Their jaws were full of sharp teeth that were perfectly equipped to catch fish, and they also had a very strong tail that propelled it through the water like a strong paddle.

The early icthyosaur Cymbospondylus

Appearances in the Walking with... series

Chased by Sea Monsters

Episode 1-Dangerous Seas

Cymbospondylus briefly appears in the opening synopsis, representing the Triassic sea. Cymbospondylus also makes a very brief appearance on the time map before the Ordivician segment of the episode. Cymbospondylus also makes a brief appearance on the time map before the Triassic segment. It also serves as the final creature that Nigel Marven encounters in the Triassic. Shortly after a Tanystropheus drops its tail and swims away, a Cymbospondylus arrives and rips the tail from Nigel's arms, snapping it up before turning around and heading back towards Nigel, gnashing its jaws. Unlike the other two reptiles Nigel encountered, the inquisitive Nothosaurus and the gentle Tanystropheus, this giant is perfectly willing to make a mean out of him. At first, the giant simply circles Nigel, before snapping at him, a warning shot. The Cymbospondylus begins swimming back towards him, jaws open, but is warded off by the electric prod that Nigel is using. However, the giant makes another approach as Nigel returns to his boat, before transitioning into the time map, where Cymbospondylus makes its final appearance in the episode before the Devonian segment.

Cymbospondylus circling Nigel

Episode 2: Into the Jaws of Death

Cymbospondylus makes a brief appearance in the opening recap, where it is seen circling Nigel before being warded off by an electric prod. Cymbospondylus also makes a brief appearance on the time map before the Eocene segment.

Episode 3-To Hell...and Back?

Cymbospondylus briefly appears in the opening recap, circling and snapping at Nigel.