The parasite appears to be over 15 times longer than the spider's body and around the same size as the arachnid's abdomen.
The parasite appears to be over 15 times longer than the spider's body and around the same size as the arachnid's abdomen.
From their hairy bodies to their rippling legs, spiders can strike terror into even the the most seasoned nature lover.
Now a new video showing a giant parasitic worm bursting from the body of a huge Australian arachnid may push arachnophobes over the edge.
The disgusting spectacle was filmed by YouTube member BaskWith2 in Australia, who was shocked to see the writhing worm after spraying the spider with insecticide.
His video seems to show a giant parasitic nematode, or roundworm, erupting from the dead spider's body in a spiral shape, before unfurling to look like a strand of wriggling wholemeal spaghetti.
It appears to be over 15 times longer than the spider's body and around the same size as the arachnid's abdomen.
Once the parasite is wriggling in a foamy sea of insecticide, the disgusted cameraman blasts it with more poison, as the video cuts out.
BaskWith2 writes on his YouTube page: "Ok so I was just editing my latest montage and this huge spider came out, so I sprayed it and killed it, then this f*****n alien worm came out of it!"
Comments include: "Just what in the sweet, holy, blessed reaches of sacred heaven is this???!!" and "Kill it with fire".
There is some conjecture as to exactly what the parasite is.
Dave Clarke, Head of Invertebrates at ZSL London Zoo told MailOnline: "This is a Mermithid nematode worm, a parasite of arthropods.
"The worm would have emerged at some point soon anyway but was obviously annoyed by the spraying of the spider.
"The size of the worm is shockingly large in proportion to the body size of the host."
The worm has also been identified as a hairworm, which looks similar to the untrained eye and can also infects spiders.
Mermithidae is an old family of nematode worms that live in arthropods such as crabs and spiders.
A specimen is even preserved in a 40-million-year-old piece of amber.
The worms are wire-like and smooth, with a tubular digestive tract with openings at each end.
The unfortunate spider likely ate its larvae, which then feasted on its host's body fluids, digestive glands, sexual organs and muscles to grow into a sizeable worm, ABC reported.
The spider would have become less mobile but because its vital organs were not eaten, probably remained alive, despite the parasite filling its abdomen and cephalothorax (mid-section).
Even without the insecticide, the spider would likely have met a grisly end, because the Mermithid nematode worm would have burst out of the creature's body, killing it.
Ingeniously, the aquatic parasite may also have taken control of its host's nervous system, causing the probably thirsty spider to seek out water and possibly drown in it, so that the parasite could continue to survive in liquid.
The video may prove even more unpalatable for some, because humans can be infected with thousands of tiny nematodes too.
Dr Brian Farrell, an entomologist at Harvard University, told The Huffington Post: "Most have no obvious effect on us, and we are mostly unaware of their presence, but a few are large enough to cause diseases such as trichinosis."
People can get roundworm, for example from swallowing microscopic eggs in food and water, or by touching contaminated soil.
