The Cambrian explosion is well known for its importance to the history of life on Earth, as it brought forth waves of biodiversity that were never seen before up until that point, like anemones, jellyfish, and sponges. Some animals from that period, like the chordates, went on to become humans and the other animals we know today, but even so, there is still a lot being discovered about what exactly lived during that early point in Earth’s history. 

On September 8th, 2021, paleontologists published a paper in the journal, Royal Society Open Science, describing a new specimen of animal that lived during the Cambrian over 500 million years ago.

According to Sci-News.com, Titanokorys gainesi belongs to a now extinct taxonomic order called Radiodonta, a group of early arthropods. 

Radiodonts can be set apart by the appendages near their mouths, which could have had many functions. Some radiodonts are speculated to have been predators, sediment feeders, or filter feeders like blue whales today. 

Cosmos Magazine says that the most famous of this order was the Anomalocaris genus, whose name means “unlike other shrimp” or “abnormal shrimp”, who were speculated to have been the earliest examples of apex predators.

It is part of a radiodont subgroup called the hurdiids, set apart by a long head and three-part shells that could take many shapes. It had multifaceted eyes, which had lenses like that of an insect or crustacean. 

In Sci-News.com, Dr. Jean-Bernard Caron from the University of Toronto and the Royal Ontario Museum says, “Their limbs at the front looked like multiple stacked rakes and would have been very efficient at bringing anything they captured in their tiny spines towards the mouth.” It is speculated that it used the fins on the sides of its back to swim, like the flaps of a stingray. 

Reconstruction of Titanokorys Gainesi, Image credit: Caron & Moysiuk, doi: 10.1098/rsos.210664.

Dr. Caron states, “The sheer size of this animal is absolutely mind-boggling, this is one of the biggest animals from the Cambrian period ever found.”

With its length of half a meter, Titanokorys was bigger than most creatures in the sea at the time it was alive. It had a large carapace, and the reason it had such a large one is still unknown, but Dr. Caron speculates that, “The huge dorsal carapace might have functioned like a plough.”

Titanokorys gainesi is now the largest known radiodont discovered so far in its own subgroup. 

The Royal Society Open Science, where the paper was published, says Titan refers to the giants in Greek mythology, referencing the size of its carapace, and the animal’s whole name translates roughly to “titanic helmet”. “Gainesi” comes from a collaborator, Robert R. Gaines, who joined the research project in 2008, and was responsible for the co-discovery of the Marble Canyon deposits, and other fossils included in the study. Like with other specimens in its order, it was discovered in the Burgess Shale deposits in British Columbia, Canada.