Giant arthropod fossil shaped like a spaceship is discovered – SoScientific

Radiodons are a group of arthropods that developed during the Cambrian explosion, between 541 and 530 million years ago. Radiodon species occupied all oceans and exhibited a variety of forms and behaviors. This group includes, for example, filter feeders, benthics, swimmers, as well as super predators, implying that the multiple species in this group occupied different ecological niches.

A study published in the journal of Royal Society Open Science just reported a description of a giant arthropod fossil. A new species of giant radiodon, called a Titanokorys Gainesi. The fossil was found in Canadian Rocky Mountain formations in Kootenay National Park, British Columbia.

reconstruction of Titanokorys Gainesi. Top to bottom: dorsal, ventral, side and front views. Image: Lars Fields, Caron and Moysiuk, 2021

The name of the genus Titanokorys refers to the term titan, due to the large size of the central element of the carapace of this species, and korys means helmet in Greek. T. gainesi belongs to the Hurdiidae group, which is the most morphologically diversified group of radiodons.

The arthropod fossil was a voracious predator

Like other radiodons, T. gainesi it has an oral cone composed of several toothed plates, a pair of front appendages, and lateral flaps along the body’s supporting gills. This species also has an anterior spine. Its long head is covered with a three-part carapace. According to one of the authors of the study, Joseph Moysiuk, the head in this species is so large in relation to the rest of the body that the individuals were “little more than swimming heads”.

the carapace of T. gainesi it is, however, wider and flatter than the average of other species of radiodon, resembling a spacecraft. This format leads the authors to believe that this species was nectobenthic, that is, that it swam close to the bottom of the sea.

“At a time when most animals were the size of your little finger, this would have been a very large predator and probably near the top of the food chain,” said Moysiuk.

T. gainesi it belonged to a time when the first recognizable ecosystems were taking shape. More than half a billion years ago, the oceans were teeming with soft-bodied organisms that fed on microbial mats. With the evolution of the first predatory animals, ecosystems became more complex and many of the main groups of animals that still live today appeared for the first time: a geological rotation called the “Cambrian explosion”.

a colossus from the bottom of the sea

The fascinating aspect of this discovery is the size of T. gainesi. The authors explain that this species is one of the largest Cambrian animals ever discovered. This arthropod could actually measure up to 50 centimeters in length.

This may not seem like much at first glance, but this predator is no match for Anomalocaris (also a radiodon), which was close to three feet long and is considered to be one of the oldest super predators.

Image: Royal Ontario Museum

According to the study’s paleontologists, the enigmatic T. gainesi it certainly had a great influence on the Cambrian benthic ecosystem. the colossus T. gainesi, whose shape seems strange among modern animals, shared the Cambrian environment with other species with equally curious morphologies.