What's That Bug? does not endorse extermination

Very small thin long white worm found in garden.
Fri, Nov 14, 2008 at 1:57 PM
I was gardening and found this very thin and small in diameter, long, almost string like. Looked like a piece of sewing thread. I was digging up dirt and happen to see it and it began moving. Wondering what this is and if its harmful to me or my pets.
Paizly Contreras
Woodland, Ca, United States

Unknown White Worm

Unknown White Worm

Hi Paizly,
We didn’t think this hairlike or threadlike worm would be that difficult to identify, but the exact identification is proving quite elusive for us. We believe this is a Nematode Worm of some type, but we are not certain. We feel confident that one of our readers will be able to properly identify your White Worm.

Hi Paizly
Free living soil nematodes are usually very small, typically less than 1 mm in length. This could be a displaced parasitic nematode, but I am inclined to think it may be a juvenile nematomorph (a.k.a. Gordian worm or horsehair worm). As juveniles, nematomorphs are parasites of insects and other arthropods. When mature, they exit their host when the host is in or near water, and they then complete their life cycle as free-living, non-feeding aquatic adults. I have seen several instances, and it is probably not unusual, where one has prematurely left a host that has died (e.g., squished on a sidewalk). If this is a nematomorph, perhaps its host died; maybe you got it with a garden implement. They are fascinating creatures and definitely harmless to humans.
There are some pictures very similar to yours at: http://www.matthewbolek.com/Nematomorphs%20for%20web%20page/Nematomorphaindex.html
KK

What's That Bug? does not endorse extermination
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2 Responses to Unknown White Threadlike Worm may be immature Horsehair Worm

  1. kkroeker says:

    Hi Paizly

    Free living soil nematodes are usually very small, typically less than 1 mm in length. This could be a displaced parasitic nematode, but I am inclined to think it may be a juvenile nematomorph (a.k.a. Gordian worm or horsehair worm). As juveniles, nematomorphs are parasites of insects and other arthropods. When mature, they exit their host when the host is in or near water, and they then complete their life cycle as free-living, non-feeding aquatic adults. I have seen several instances, and it is probably not unusual, where one has prematurely left a host that has died (e.g., squished on a sidewalk). If this is a nematomorph, perhaps its host died; maybe you got it with a garden implement. They are fascinating creatures and definitely harmless to humans.

    There are some pictures very similar to yours at: http://www.matthewbolek.com/Nematomorphs%20for%20web%20page/Nematomorphaindex.html

    KK

  2. Angela Hottinger says:

    I was so freaked out when I look down and saw what looked to be a piece of white thread material in my grass, MOVING….WHAT? I yelled to my husband for him to view and see if he knew what this “moving white thread” was. When he said no…my reply was let’s Google it…and here I am. There are horses by my yard, therefore I believe this may just be my answer. I am very relieved to know that they are not harmful to the children or pets, or myself for that matter. Anyway…thank you for your answer it was very useful.

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