Horsehair Worm facts: not for the squeamish | Animal Fact Files

Horsehair worms are an entirely parasitic animal phylum. As adults, these worms live in streams, ponds, rivers... your toilet(!), but horsehair worm larvae live inside arthropods. Preferably terrestrial arthropods. Which means for the adults to return to water they have to mind control their hosts back into the water. It can be a gruesome affair. Thankfully, horsehair worms want nothing to do with us!

Scientific Name: Phylum - Nematomorpha
Range: worldwide except Antarctica
Size: an inch (2.54cm) to more than 6.5 feet (2m) in length
Diet: absorb nutrients from arthropod hosts
Lifespan: a few months to a few years

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[angelicanjelika]

I thought he was going to reassure us by saying " dont worry our stomach acids will kill it " but nah he said it will literally just come out my nose . This made it 100× worse .

[ElementofKindness]

_". . . . you don't have to really worry. In fact, if you accidentally swallowed an adult horse hair worm, it would likely crawl out your nose or mouth."_
*THAT'S NOT HELPING!!!!*

[archangel]

I really appreciate you covering the Horsehair Worm. Several years ago I killed a beetle or a cricket, I can’t remember exactly but it was one or the other, and immediately after I killed it a thin worm like creature crawled out of it. The entire experience totally creeped me out and at the time I didn’t know what I had just witnessed. Thanks to this video I now know what it was.

[TheTrueMariWho]

Gives “creepy pasta” a whole new meaning 😆

[niklash]

“Don‘t worry if you eat one, it will make its way out of you nose or mouth”. I am still worried

[misterhanley]

don't worry if you eat one, it will come out of your mouth or nose! I imagine sitting down at dinner and a long strand coming out of my nose/mouth. I understand nature works in strange ways and there is a place for everything but parasitoids and these types of parasites are gross.

[bizichyld]

Praying mantis: *exists*

Horsehair worm: “it’s free real estate!”

[michaelslater]

Thank you. When I was younger, I used to see a lot of horse hair worms in mud puddles. My dad always called him horse hair worms but I wasn’t sure if that was the official name for them.

[Cruddy]

So if they were eatan by humans, they... literally find their own way out of our mouths....?

My god thats like something from a body horror movie

[TheSunBringsJoy]

“Horsehair worms are harmless to vertebrates, because they can't parasitize people, livestock, pets, or birds. They also don't infect plants. If humans ingest the worms, they may encounter some mild discomfort of the intestinal tract, but infection never occurs.”

[itsdalu]

Cricket: comes by
Hairworm:oh boy the u haul is finally here

[ez]

I remember finding one of these when I was like 8. I was out camping and I found a cool blue praying mantis that was moving sluggishly and wasn’t aggressive. I sprayed some water on it just to see what it would do (because I was a dumb kid and had a bit of a mean streak for bugs) and it falls to the ground and starts convulsing, and lets out this massive wriggling brown thing. No one believed me and I eventually thought I had dreamt it up so it’s nice to have that experience validated

[eatwhatukiii]

I have seen these in puddles and leaf litter around here (and I also have horses) and these worms do indeed look and feel just like a horse’s thick tail hair. The big difference is they MOVE. Heebee jeebee factor of 10!

[ShennyIsLive]

I watched this video while eating a bowl of spaghetti, because I'm a crazy asshole.

[alfiemcfarland]

Horse hair that becomes them after being exposed to water. Sounds like a yokai.

[avoqado]

Calm matpat telling me if I eat this, it will jump back out of my mouth or nose. Thanks.

[FungusApe]

It seems that crawling out of some orifice in the human body is definitely better causing some mayhem from the inside out and taking over the brain turning you into a mindless titan

[syrenet]

"Dont worrry, itt'll escape your body trough your nose"
Oh thanks.

[matttheginger]

Several years ago I was in WV and happened to see a cricket acting strangely outside in the rain. When I got closer I saw a horsehair worm crawling out of the cricket. It was bizarre, and I ended up keeping the worm in a jar

[moimeme-vu]

As a child from Québec, me, my brother and cousins find something really similar at the crystal beach. It was floating on the water and I remember that we place it in our hands and find it very strange to see it move ! ! We never saw this before ! After that day, my brother found out it was maybe a " cheveu de mer" in french.