Well this is truly disgusting. Watch as one of nature's most efficient killing machines slowly chows down on the face of a fly as it writhes helplessly in its arms. It's the sound that really got to us…

We've seen some pretty gross behaviour from invertebrates of late. A worm-eating leech sucking its prey up like a vacuum cleaner. A maggot's body liquify inside its pupa so it can morph into a fly, what it looks like when various animals eat each other. And now the praying mantis is back for more.

This footage shows a European mantis (Mantis religiosa) catch a bee-mimicking fly in its arms - which happen to be covered in tiny spines for extra grip - and start eating away at its face. First the mantis eats the fly's mouthparts, then it moves on to its brain. If you can stick it out to the end of the video, you'll see it clean out the fly's head cavity, devour both eyes, and then move on to the body, because the entire head is now gone. Every morsel.

In the wild, praying mantises will basically eat anything that they can catch. For the larger species, this includes scorpions, lizards, frogs, birds, snakes, fish, and even mice. They're equipped with several different mouthparts designed to slice, rip, grind, and suck at their prey, and they'll do this over and over again across their 10 to 12-month lifespan. Lock your doors, and come out for no one if you know what's good for you, flies…

Source: SPLOID