The mimic octopus is known to impersonate toxic flatfish, lionfish and even sea snakes by creatively configuring its limbs, adopting undulating movements, and displaying bold brown-and-white colour patterns, a new study says.
Thanks to these brazen habits, it can swim in the open with relatively little fear of predators. Conversely, the small and timid jawfish spends most of its adult life close to a sand burrow, where it will quickly retreat upon sighting a predator.
During a diving trip in Indonesia in July 2011, Godehard Kopp of the University of Gottingen, Germany, filmed an unexpected pairing between the two animals.
Like a lackey clinging on to the big man on campus, the black-marble jawfish was seen closely following a mimic octopus as it moved across the sandy bottom.
The jawfish had brown-and-white markings similar to the octopus, and was difficult to spot among the many arms. The octopus, for its part, did not seem to notice or care.
Kopp sent the video to Rich Ross and Luiz Rocha of the California Academy of Sciences, who identified the jawfish species. Since this association had not been recorded before, they published their observations online last month in the scientific journal Coral Reefs.
The authors surmise that the jawfish hitches a ride with the octopus for protection, allowing it to venture away from its burrow to look for food-a case of "opportunistic mimicry".
"This is a unique case in the reefs not only because the model for the jawfish is a mimic itself, but also because this is the first case of a jawfish involved in mimicry," said Luiz Rocha, assistant curator of ichthyology at the California Academy of Sciences.
"Unfortunately, reefs in the Coral Triangle area of southeast Asia are rapidly declining mostly due to harmful human activities, and we may lose species involved in unique interactions like this even before we get to know them," added Rocha.