There's a type of octopus called the Giant Pacific. It's pretty big, arguably the biggest on our planet. They can be found in the coastal North Pacific—places like Japan, Korea, Russia, California, British Columbia, Washington, and Oregon. But it's recently been found out that what we've been calling the Giant Pacific octopus actually includes two different species. 

Enter Alaska Pacific University undergraduate student Nathan Hollenbeck, who, while working on his senior thesis on shrimp fishing bycatch, made the discovery. After setting shrimp traps, some giant octopuses, who were probably looking for a good meal, got themselves stuck in the contraption, Earther reports

Hollenbeck noticed that one of the animals was a Giant Pacific, but realized that a second octopus looked markedly different, with frill on its body and two white spots on its head. To confirm that the frill octopus was different, Hollenbeck took samples. He cut off pieces of the animal's arm (which sounds horrible—and lightweight is—but they do regenerate) and took some skin samples to peep the whole DNA situation. 

After studying the samples, Hollenbeck concluded that the two octopuses were indeed different species. He and his advisor David Scheel published the findings  in the American Malacological Bulletin in a paper called "Frilled giant Pacific octopus." 

"I’ve been thinking: why would an octopus have a ledge coming off its body like that? Maybe we’re seeing differences in their habitat selection and ecology reflected by differences in their body," Scheel​ told Earther

While Earther reports that scientists have long suspected the Giant Pacific octopus was an "umbrella name" that encompassed other species, it's a cool discovery nonetheless.