16.05.2024

Big eyes, big find – New ichthyosaur species discovered

Science News
Digitale Rekonstruktion des Fischsauriers Argovisaurus martafernandezi
Digital reconstruction of the ichthyosaur species Argovisaurus martafernandezi. (Copyright: Beat Scheffold)

Named after their most striking feature, their unusually large eyes, the ophthalmosaurs (ancient Greek for "eye lizards") were a group of ichthyosaurs that emerged from the few survivors of the mass extinction at the end of the Triassic period around 201 million years ago. The first representatives of these marine reptiles are known from the early Middle Jurassic, around 170 million years ago, from where they developed into the predominant group of ichthyosaurs.

Despite the wide distribution of ophthalmosaurs, their evolution has not yet been sufficiently studied, as only a few sites with vertebrate fossils are known from the Middle Jurassic of Central Europe.

However, a team led by paleontologists Dr. Feiko Miedema and Dr. Erin Maxwell from the Natural History Museum in Stuttgart has now discovered a new species of ophthalmosaur. They described the previously unknown ichthyosaur based on a fossil from the Swiss Jurassic and named it Argovisaurus martafernandezi. The name of the large-eyed marine reptile is derived from the place where it was found in the Swiss canton of Aargau and also honors the Argentinian vertebrate paleontologist Marta Fernández.

The fossil remains of Argovisaurus martafernandezi were found more than 20 years ago, but have now been identified as a new species with the help of modern CT technology. The almost completely preserved skull was scanned and a 3D reconstruction of the animal was created. The examination revealed that this individual was probably an adult animal with a body length of 4.5 to 6 meters, which is comparable to the size of today's great white sharks. Further investigation showed that Argovisaurus martafernandezi is one of the earliest representatives of the ophthalmosaurs and thus represents an important milestone in understanding the evolution of this group of ichthyosaurs.

The original article was published in the scientific journal “BMC Ecology and Evolution”.

 

Original publication