Open Up And Say "Ah!"

One of the best things about the underwater world is that there are so many species that have more than one fascinating feature hidden up their sleeves. Creatures that exhibit one amazing physical ability or type of behaviour will often boast another one as well.

Such is the case with the Slingjaw Wrasse (Epibulus insidiator). Found in the shallow tropical waters of the Indian and Pacific Oceans, the Slingjaw is, as the name suggests, blessed with some of the most impressive mouthparts in the ocean. This marine marvel’s jaws are designed to extend nearly half the length of its own body, allowing it to snatch its prey out of otherwise inaccessible nooks, crannies and crevices in the reef.

Its amazing lower jaw is almost free-floating, and together with a fiendishly complex array of other bones and tendons, it can extend the whole lot like an otherworldly extra from a science-fiction movie. Luckily the Slingjaw is too small to pose a threat to humans and is content to snatch up small fish, crabs and shrimp in under one 30th of a second.

Its reproductive behaviour is perhaps even more impressive however; as it is a “protogynous hermaphrodite”, meaning that each wrasse begins life as a female and gradually becomes a male as it grows older and larger. Individuals will also change their appearance greatly as they change sex, so that females are either light brown or yellow, while males are much more brightly coloured with bits of white, yellow, brown and orange and a distinctive dark stripe behind their eyes.