A giant new Cambrian-era creature has eclipsed almost everything else in the sea

The Cambrian era, when animal life exploded into astonishing diversity 541-485 million years ago, once again surprised biologists. The latest discovery is Titanokorys sheaths, a creature which would be remarkable today for its form, but which was then distinguished by its enormous size, compared to the small animals of its time.

Titanic Choir was discovered in the famous Burgess Shale, a site in the Canadian Rockies that gave us the first detailed glimpse of the staggering diversity of shapes that appeared around 508 million years ago. Many of them were so strange that some were named after trips on acid and most were never seen again.

Despite all their diversity, however, most of the species buried in the Burgess Shale were smaller than a credit card. Titanokorys, on the other hand, was half a meter long (20 inches), an article published in the Royal Society Open Science reports.

“The size of this animal is absolutely staggering, it is one of the largest animals from the Cambrian period ever found,” Dr. Jean-Bernard Caron of the Royal Ontario Museum said in a statement.

Although it has only been scientifically described now, Titanic Choir has been known to part of the general public for two years, with its discovery appearing in the CBC documentary First animals.

Titanic Choir was a radiodon, a group of primitive arthropods whose most famous member was Anomalocaris. Radiodons are identified by their multifaceted eyes, cone-shaped mouth filled with toothed plaques, and nightmarish claws that appear to come straight out of the head to grab prey. They swam across the Cambrian oceans pushed by shutters. Originally identified in the Burgess Shale, radioodonts have been found at other sites of similar age, indicating their Cambrian success status.

“Titanic Choir is part of a subgroup of radiodonts, called hurdiids, characterized by an incredibly long head covered with a three-part shell that has taken on a myriad of shapes. The head is so long in relation to the body that these animals are really little more than swimming heads, ”said the co-author and PhD student at the University of Toronto. Joe Moysiuk.

What exactly the shell was used for, let alone why they came in so many different forms among the radiodon species, is a mystery. However, the authors believe Titanokorys the large, flattened carapace, which lies midway between long and short-shelled species, indicates a species that lived near the seabed.

“These enigmatic animals certainly had a significant impact on the ecosystems of the Cambrian seabed. Their limbs at the front looked like multiple rakes stacked up and would have been very effective in bringing whatever they caught in their tiny thorns back to their mouths. The huge back shell could have functioned like a plow, ”Caron said.

Ecosystems can only support a small number of large predators. Although 12 (mostly fragmentary) Titanic Choir specimens were found, it was much rarer than the smaller radiodon, Cambroaster falcatus, who lived in similar places and may have competed with Titanic Choir for prey.