Pray this mantis doesn't find you...
In this instalment of "Swim a mile in their seas" I will be looking at perhaps the most vibrant marine crustacean found in the Indian and Pacific Oceans. For those of you that are shrimp lovers, you may want to stray away from this one!
Odontodactylus scyllarus, otherwise known as the "mantis shrimp" is a part of the order Stomatopoda and is in fact not a shrimp. They are carnivorous marine crustaceans and have been around for more than 400 million years! That makes them older than dinosaurs! These creatures are typically solitary (live alone) and spend their time hiding in rocks or burrowing underground. This particular crustacean is unlike others, they will sometimes hunt down and kill prey instead of acting solely as ambush predators. I bet you're wondering how a tiny shrimp can possibly inflict any damage on other organisms...well...a typical mantis shrimp can grow to around 4 inches long, however, some have been recorded at over 15 inches!
Another interesting fact about the mantis shrimp is its eyesight. Humans are only able to detect three channels of colour (red, green and blue), the mantis shrimp can detect 12 channels of colour as well as UV (ultraviolet) and polarised light. This species is thought to have the most complex eyes in the animal kingdom. The mantis shrimp itself has a variety of colours from brown to more vivid colours as seen below.
So what makes this species so adapted for killing and hunting its prey?
In one word, claws. Mantis shrimp can be distinguished by their ability to kill prey. They have a second pair of appendages that have been adapted to do one of two things. The first involves the shrimp impaling their prey with spear-like structures on the ends of their limbs. They are known as "spearers" and have spines that have barbed tips that they used to stab and snag their soft-bodied prey, primarily worms and fish. The other type are known as "smashers" whereby they have a club-like appendage used to smash their meals apart. It is thought that the force of this 'punch' is equivalent to the force of a bullet from a .22 caliber rifle.
The ability of this mantis shrimp to punch its prey is a unique adaptation seen in the marine world. Studies have shown that for a split second after their 'punch', cavitation bubbles are formed, they are superheated bubbles with a small flash of light as well as causing the surrounding water to reach temperatures of 4,400oC for a split second, that is almost as hot as the sun! These punches also prove difficult for aquariums as they are strong enough to punch holes in the glass.
If you are ever fortunate to come across this organism bear in mind that its nickname is "thumb-splitter" in some cultures...so approach with caution...