A 430-million-year-old fossil is, in fact, an entirely new species of echinoderm and researchers have chosen to name it Sollasina cthulhu – a reference to Lovecraft’s infamous tentacled monster, Cthulhu.

The now-extinct marine beastie has been described for the first time in a study published in the Proceedings of the Royal Society B.

For the uninitiated, Cthulhu is a fictional character concocted by the late writer H. P. Lovecraft, who first appeared in a short story called The Call of Cthulhu in 1928. Lovecraft described his monster as an extraterrestrial being with "an octopus-like head", "a scaly, rubbery-looking body", "prodigious claws", and "long, narrow wings" that spends his days in deep slumber at the bottom of the Pacific Ocean.

Even in his sleepy state, he is able to control human dreaming. So much so that it has assembled together a global cult that worships him as a god.

_{Despite his troublesome reputation (as a racist and anti-semite), Lovecraft has spawned his own subgenre: "Lovecraftian horror", concerned with the horror of the unknown. Aside from some on the nose references to Cthulhu in cartoons like "South Park" and "Rick and Morty", similar themes have popped up in movies like Netflix's "Bird Box" and DC's "Aquaman". Netflix/YouTube}

Fortunately, this critter is not nearly as terrifying as the notorious Cthulhu. Not only has it been dead for 430 million years, but it is also a wee 3 centimeters (1.2 inches) long. That puts it roughly in the same category (size-wise) as your average house spider. And like a spider, the Sollasina cthulhu was extremely leggy, with 45 tentacle-like tube feet that it used to creep along the ocean floor and catch lunch. 

"In this paper, we report a new echinoderm – the group that includes sea urchins, sea cucumbers, and sea stars – with soft-tissue preservation," co-author Derek Briggs, a Yale palaeontologist, said in a statement. Specifically, an ophiocistioid – a now-extinct group of echinoderms, closely related to modern-day sea cucumbers.

To study the creature's physiology, researchers used a technique called high-resolution physical-optical tomography. This involves grinding away at the fossil, taking photos as each thin layer is removed. The end-product is hundreds of images that can be collated to form a 3D image – or "virtual fossil". 

From this "virtual fossil", researchers were able to figure out the animal's internal water vascular system. And thus, show that it is more similar to a sea cucumber than a sea urchin. 

"The water vascular system operates the tentacle-like structures that they used for locomotion and food capture," Briggs added.

"The tube feet of living echinoderms are naked, but in the ophiocistioids they were plated. Our analysis strongly suggests that ophiocistioids diverged from the line leading to modern sea cucumbers."

We're just glad that this particular Cthulhu has no plans to take over humanity. Or, indeed, run for president.