Atlantic octopus seen imitating flounder

WOODS HOLE, Mass., March 3 (UPI) -- U.S. scientists say they've documented for the first time an Atlantic octopus mimicking a flounder -- only the fourth report of cephalopod mimicry.

Marine Biological Laboratory senior scientist Roger Hanlon and his colleagues say they've observed the camouflage capabilities of the Atlantic longarm octopus, Macrotritopus defilippi, whose strategy for avoiding predators includes expertly disguising itself as a flounder.

While Hanlon and others have documented two other species of octopuses imitating flounder in Indonesian waters, they said their new report marks the first of flounder mimicry by an Atlantic octopus.

Comparing still photographs and video footage from five Caribbean locations, Hanlon -- along with graduate students Anya Watson and Alexandra Barbosa -- observed what they described as uncanny similarities between the small and delicate octopus and the peacock flounder, one of the most common sand dwellers in the Caribbean.

They compared not only coloration, which in each animal resembled the sandy seafloor, but swimming speed and form.

Just like flounder, the octopi contoured their bodies to hug the wavy seafloor, tapering their arms behind them. They also swam with the same fits, starts and speeds as flounder.

The research is reported in the February issue of The Biological Bulletin.