This unbelievable footage shows the gruesome moment a worm bursts through the dead corpse of a praying mantis in a scene akin to the classic Sci-Fi film .
The video shows the praying mantis walking across the floor while the person holding the camera prods it before killing it with insect repellant.
But seconds later something can be seen moving at the rear of the insect and then a huge worm bursts out and wriggles across the floor.
Experts shown the video by German newspaper Bild said it was clearly a parasite that had been eating alive the praying mantis.
They said it appeared to be a horsehair worm or Nematomorpha.
The praying mantis is a protected insect in Germany where it is extremely rare but it is not clear where the video was shot.
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The video was posted last May but only went viral this week when it was highlighted by the German newspaper's science page.
Some of viewers on You Tube expressed doubts about the authenticity of the video, but Professor Christopher Darling from the University of Toronto said it's a fairly common phenomenon.
He said: "I am pretty sure that this is real, and not a hoax. I have seen and photographed similar things a number of times."
Darling, who is also a senior curator of entomology at the Royal Ontario Museum, said the worm was likely tightly packed inside the abdomen of the insect until the insect died.
"And yes, they do look very long, but they are very skinny," he wrote.
The experts said that nematomorph hairworms do not just colonise the belly of their hosts, they eat them alive causing erratic behaviour that can make the insects to fall into water - perfect for the parasite as they need water to reproduce.
In 2002, researchers investigated anecdotal reports of insects infected with the parasite "committing suicide" by jumping into water.
The researchers compared the behaviour of crickets infected with the worm against uninfected crickets, and found the infected ones were more likely to jump into the water.
Water is fatal for the crickets, but the parasite relies on the water to reproduce.
The worms can grow to two metres long, and the adults live freely in water, but the larvae are parasitic on various insects and crustaceans.
