The mimic octopus is a stealthy swimmer (and a furious lover) but it's not the only master of disguise in the ocean. While swimming off of the coast of Indonesia last July, diver Godehard Kopp noticed that a black-marble jawfish was surreptitiously hitching a ride with the mimic octopus.
The mimic octopus can ape other venomous sea fauna — such as lionfish — so predators tend to avoid it. By matching the octopus' color and pattern, this vulnerable fish, which normally occupies a cozy burrow, was able to blend in with the cephalopod's mass. Furthermore, the octopus didn't appear to mind its fleeting sidekick.
For a good 15 minutes, this black-marble jawfish took the mollusk express, presumably to find food beyond its burrow. As nifty as the fish's behavior is, the researchers suspect that this isn't an everyday interaction. From the recent paper in the journal Coral Reefs, "Opportunistic mimicry by a Jawfish":
Since the Black-Marble Jawfish is distributed from Japan to Australia, whereas the Mimic Octopus is restricted to the Indo-Malay region, we think this is a case of opportunistic rather than obligate mimicry.