White cobweb-weaver spider

2009 February 7

I was down in the basement last August trying to decide which of the many spiders down there to catch and photograph, when this little lady caught my eye. Where most of them were dark brown to black, she was practically white!

She’s clearly a cobweb-weaver, family Theridiidae – she had a cobweb-style web (a loose, disorganized 3-dimensional mess of threads), and her body shape is typical for cobweb-weavers: somewhat spindly legs,and a bulbous abdomen.

For once, I actually got a picture of her underside, although it did come out a bit blurry:

One thing about light-colored spiders is that it is much easier to see their eyes than in the dark-colored spiders. Hers stand out very well, and you can clearly see all of them. I think she technically has eight eyes, but the ones on the sides (the lateral eyes) have fused so that they look like one big oval-shaped eye instead of two round eyes.

We get to see a bit of fang here, too: she was opening up her chelicerae just a bit and showing them to me. I think she might have been slightly peeved by this point.

I tried to identify this further myself, but I still don’t know enough to interpret the ID keys in the spider guide. So, I went to BugGuide, and Lynette Schimming suggested it was probably in the genus Enoplognatha, which I can certainly go along with. Specifically, I think it is Enoplognatha ovata. Now, those of you who checked that last link are probably saying at this point, “What, are you nuts? Those have huge red stripes on them, they don’t look anything like this one!” This is true, but it turns out that this species doesn’t always have the red stripes. They are highly variable in color, sometimes the stripes are very pronounced, and sometimes they are practically invisible. You can still see them in this specimen, but they are very faint:

The other thing that makes me think this is Enoplognatha ovata, though, is that it is an introduced European species. As soon as I read that, I rolled my eyes and said to myself, “Well, of course it would be.” By and large, I’m finding that the introduced species are very likely to be the most common species around here.

About this time, it may have occurred to you that Black Widow Spiders are also cobweb-weavers, which leads to the obvious question of whether this one is sufficiently venomous to be dangerous to humans. That’s an easy one to answer: No. Their venom is nothing significant, and they are such little spiders anyway (her body is only 8 mm long) that I doubt they could manage much of a nip in the first place.

14 Responses leave one →
  1. February 10, 2009

    I love spiders! Great photos. Never seen this species before.

  2. February 10, 2009

    I’m not sure if I’ve seen them before or not, but I’m pretty sure I’ve never seen the color phase with the prominent red stripes.

  3. Richard permalink
    July 26, 2009

    I caught a spider similar to this one, the abdomen has two green lines on the dorsal side and a wide green line on the ventral side of its abdomen. It is in a jar, and leaves disorganized webs on the top. I caught a wasp (about 1.5 inches long, the spider is just a bit bigger then the wasps head), and put it in the jar, since the spider had already killed and eaten a small wasp about its own size. The spider hit it once then retreated, and in less then a minute the wasp was convulsing and died. I noticed when I caught it, the spider was actively hunting a fly, it dropped down from the wall above it and bit, so I decided to catch it and try to identify it, since it was hunting rather then waiting for prey to get caught in its web, and then after killing the wasp in around 45 seconds, I wanted to see how venomous it might be. I also found it outside, near my mother’s flowers, not inside, or in a dark area.

  4. Muhammad Smith permalink
    August 22, 2009

    I found a small spider that was very white with a red stripe down each side of his back. If anyone can identify such a spider please post it on this website.

  5. Arthur permalink
    June 17, 2010

    I found a small almost neon green spider with the tail portion being a solid white, and the top of the white part looks like a skull face. Does anyone know what type that might be?

  6. June 17, 2010

    Arthur: Spider ID is notoriously difficult, but did it look anything like this spider?

  7. Jon permalink
    June 20, 2010

    Do their bodies come in different colors? I found a spider last night with a big white abdomen but it’s body was the color of a recluse. Also it had killed a much larger spider than itself. Any thoughts??

  8. Marshall Lucas permalink
    July 16, 2010

    Your specimen actual resembles a lineata more than an ovata.

  9. July 17, 2010

    When I just checked on BugGuide, it looked like they were saying that the species name was “ovata”, and that “lineata” was one of three subspecies of “ovata”.

  10. September 4, 2010

    I killed two of them outside my house in Bradenton, Fl. Their web was strong enough to capture a rhino beetle and have him for a meal. And they made a web between two trees (6′) in my backyard. Had to kill them they made a mess with the tree leaves blowing around my house.

  11. Jessica permalink
    June 29, 2011

    We have a whole bunch of these little ones at my work. It is a pool and they live high up in the crevise of the building. Cute!

  12. TANYA permalink
    August 3, 2011

    Thanks I believe i just found one of these. truly fascinating. thanks

  13. Kylie permalink
    October 20, 2011

    I found a very tiny spider that looks like this one hanging out in my hair, i left it there and would let it crawl on my fingers, it didnt bite me, ive been trying to identify it. The underside of its abdomen had what appeared to be a white arrow. It looked like a speck of white in my hair.

  14. Kitty permalink
    September 3, 2014

    We have these in our garden where they seem to really love to nest in our curly kale plants. I knew they were some sort of cobweb spider very similar to the trianulosas (sp?) we have in the house, but I’d not seen this very light green to white cobwebber in a garden before. We normally have the big Orb Weavers, this year these little gals. Lovely little spider, delicate and elegant.
    interesting to watch and very protective of their egg sacks.
    I try to save as many as I can while cleaning kale in the sink, and put them back outside.
    We are in Portland OR

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