The mimic octopus (Thaumoctopus mimicus) eluded formal description until 2005.

Perhaps it was this banded cephalopod's incredible impersonation abilities that kept it from science for so long. Its many guises and odd behaviors have been caught on video, but a new specimen, captured off the coast of Thailand, gives researches new evidence of the octopus's range.

Beyond the clever color and textural camouflage of its cousins, the mimic octopus actually impersonates other animals. It can flatten all of its arms together and wave its way along the bottom like a sole. It can also splay its arms to glide through the water like the poisonous lionfish. Or, my personal favorite, it has been observed burying six of its arms in the sand and extending only two opposing arms to look like the venomous banded sea snake. These tricks apparently work. The mimic octopus seems to have evolved a strong pattern of these behaviors.

The species has been observed in Indonesia, where it was first described, as well as Malaysia and the Philippines. But it has rarely been seen farther north, in Thai waters. The new catch, landed in the upper Gulf of Thailand, was described last month in the Phuket Marine Biological Center Research Bulletin [pdf].

The small female octopus in question had been hanging out on the soft sea bottom about 65 feet down. Her body was just shy of two inches long, and she weighed just more than an ounce. All but one of her long, spindly arms seemed to have been damaged, and the tips might have been voluntarily cast off at some point—perhaps in battle or to distract a predator.

The mimic octopus is also fairly unusual in its hunting habits. Most octopuses are active at dawn, dusk or night. But the mimic octopus—perhaps emboldened by its quick disguise tricks—searches during the day. "The origins and affinities of the mimic octopus are unclear," note the paper's authors. "Lifestyle and habitat preferences might have evolved through a habitat shift from an ancestor that was active during the day, or they could have evolved from an ancestor that was active on soft sediment at twilight or during the night."

The new find suggests a larger range for this wily cephalopod. But, as the authors of the new description note, "there is still much to be learned about the biology and life history of this species."

To read more about the the amazing octopus, check out Octopus! The Most Mysterious Creature In the Sea.

Illustration courtesy of Ivan Phillipsen