We know that octopuses are among the animal kingdom's master camouflagers, but we didn't know that they were so good that a whole species could be hiding in plain sight.

This new species is called the frilled giant Pacific octopus, and it's been mistaken for the giant Pacific octopus (Enteroctopus dofleini) all this time. Researchers had suspected that there was another giant Pacific octopus species since at least 2012, when Alaska Pacific University and U.S. Geological Survey scientists collected DNA evidence from a "cryptic" species. Regrettably, the team didn't photograph the species to get visual confirmation.

The mysterious nature of this potentially new species attracted the attention of Alaska Pacific undergraduate Nathan Hollenbeck, who decided to investigate the issue for his senior thesis. His adviser, David Scheel, was the lead researcher on the team that discovered "Octlantis" earlier this year.

Searching for a new species

To find out if this mystery octopus was a different species from the giant Pacific octopus, Hollenbeck needed to collect a number of samples. The best way to do that was to go shrimping. Well, to go through shrimpers' bycatch, anyway. (Bycatch is fish or other marine species caught unintentionally during the fishing process.)

Octopuses are a common presence in shrimp bycatch in Alaska and, through this method, Hollenbeck and Scheel caught and collected data from 21 individual octopuses, seven of which were visually distinct from the giant Pacific octopus that we know.

A frilled giant Pacific octopus in a lab's tank Behold, the frilled giant Pacific octopus. (Photo: Alaska Octopus Projects)

It didn't take long, at least on a visual level, for the researchers to determine that they had a new species on their hands. As the name implies, the frilled giant Pacific octopus sports a frill along the length of its body. Even the octopuses' eyes have a little frill atop — a thin, raised major papillae over each of its eyes. Some even had frills around their eyes, sort of like eyelashes, but it was really just more papillae. Additionally, the frilly octopus also has two white spots on its head.

The giant Pacific octopus only has one such spot on its head, but it doesn't have all the frills.

Visual confirmation is only one step of the process, however. Genetic samples had to be collected and analyzed as well to be sure that this dressed-to-the-nines cephalopod was indeed a different species.

Gathering genetic information from octopuses involves taking snips from their tentacles. The process is invasive to be sure, but the tentacles do grow back after a period of time. Hollenbeck and Scheel did perform this process, but Hollenbeck decided to take his thesis project to a level beyond just identifying a new species; he tested a noninvasive process for gathering DNA.

Getting human DNA can involve a few different methods, including swabbing the inside of cheeks. Hollenbeck and Scheel did more or less the same thing with their octopuses. Taking some cotton, they ran it along the skin of the octopus and analyzed what they found. The swabs yielded a 97 percent reliability when compared with the tentacle snipping results.

And those results confirmed the physical characteristics: The octopus was a whole new species, different from Enteroctopus dofleini.

Next steps

The visual identifiers will help researchers pick out the frilled giant Pacific octopus from its cousins, and that will help researchers get a sense of how common it is. Hollenbeck and Scheel found that the frilled giant Pacific octopus resides only from Juneau to the Bering Sea, a smaller range than the giant Pacific octopus, which is found all across the northern Pacific Ocean.

The presence of the frilled giant Pacific octopus also lends some credence to the possibility that, as many scientists have thought for a while now, the name giant Pacific octopus may just be an "umbrella" term of sorts. If it is, there could be a whole range of species that are just waiting to be discovered.

This octopus has been right under our noses
We've suspected there was another species of giant Pacific octopus, and now we know for sure — this one has frills.