More than 500 million years before Matt Groening and “The Simpsons” introduced us to Blinky, a mutated fish with an extra eye swimming through Springfield’s Old Fishin’ Hole, a three-eyed predator chased prey through seas of the Cambrian Period. Once it caught its quarry, a pair of spine-covered grasping claws and a circular mouth covered in teeth would finish the job.

Known as Mosura fentoni, this creature is a worthy addition to the bizarre bestiary preserved in the Burgess Shale, a substantial fossil deposit in the Canadian Rockies. However, the animal’s anatomy, described Wednesday in the journal Royal Society Open Science, reveals that Mosura may not be as alien as it looks.

The first Mosura specimen was unearthed more than a century ago by the paleontologist Charles Walcott, who discovered the Burgess Shale in 1909. Over recent decades, paleontologists at the Royal Ontario Museum in Toronto have uncovered dozens of additional Mosura fossils, which they nicknamed “sea moths” because of flaps on the critters that help them swim and that look similar to wings.

They were not fish, but it was clear that sea moths were related to radiodonts, a group of ancestral arthropods that dominated Cambrian food chains. But a closer inspection of the animal would not happen until a trove of Mosura specimens were unearthed in 2012 in Marble Canyon, a Burgess Shale outcrop.

“Having this collection of both old and new specimens kicked us into gear to finally figure this animal out,” said Joseph Moysiuk, a paleontologist who studied the Marble Canyon fossils as a doctoral student.

Dr. Moysiuk teamed up with his adviser at the Royal Ontario Museum, Jean-Bernard Caron, to examine some 60 sea moth specimens. Like other Burgess Shale creatures, many Mosura specimens were well preserved, retaining features like digestive tracts and circulatory systems. Some even possessed traces of nerve bundles in each of the creature’s three eyes.