Large, black, furry jumping spider

2012 May 2

I found this unusually large jumping spider on one of the roof support pillars on our front porch on July 18, 2011. He was a big, black, furry, sinister-looking specimen, over a centimeter long.

Normally, jumping spiders are kind of cute, but this one has more the air of the insect murderer that he actually is.

In this closeup of his face[1], we see that he’s got iridescent green chelicerae (his mouthparts), so he’s probably one of the Phidippus jumping spiders.

Jumping spiders use all four of their rearmost legs for jumping. In this next picture, you can see the very hind pair shaped something like a grasshopper’s hind legs, all ready to push backwards. The pair in front of that are oriented a little bit differently, so that when he jumps they will pull forward rather than pushing backwards.

To show how this works, here’s a short video I found on YouTube that was shot with a high-speed camera[2].

I think the use of four legs for jumping rather than just two gives him far more control than most small jumping arthropods have. And he needs precision very much. Things like grasshoppers, leafhoppers, and fleas are using their jumping abilities to escape from predators, so they don’t care about fine directional control. They just want to get away. Jumping spiders, on the other hand, are using their jumps to intercept. They don’t have to jump far, but they do have to have pinpoint precision.

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[1] In the picture, it looks like he has human-like eyes. That’s an artifact of the way my Cone Macro Flash Concentrator directs light from the camera flash. The white “iris” is a reflection of the posterboard cone that most of the light from the flash is bouncing off of; the black “pupil” is the circular end of my camera lens; and the glowing-white spot in the middle that makes him look demonical is the light that traveled directly from the on-camera flash and bounced back from his eye. And what looks like a baggy lower eyelid is a reflection of a corner of the white sheet of paper he’s standing on. It’s just a coincidence that it all lined up to look like human eyeballs, I swear!

[2] There is a note on YouTube from the person who posted this video that the slow light-dark strobing of the background brightness was due to being shot under fluorescent lights, which flicker either 100 or 120 times per second, depending on whether they are powered by 50 or 60 cycle AC. So since the brightness strobes about five times in the course of the jump, that means the jump only took about 1/20th of a second – too fast to see with the naked eye.

17 Responses leave one →
  1. sandy permalink
    May 2, 2012

    Assassin!

  2. Carole permalink
    May 2, 2012

    WOW!

  3. Kathleen permalink
    May 3, 2012

    He was beautiful- I hope you didn’t him.

  4. Kathleen permalink
    May 3, 2012

    Left out ‘hurt’- I hope you examined him and let him go.

  5. May 3, 2012

    Oh, certainly. He was completely unharmed by the experience, and went right back into the yard to go about his business when we were through. I like having jumping spiders around.

  6. May 3, 2012

    I love the close-up shot of the eyes. Freaky. Like it’s channeling Cthulhu.

  7. Brian permalink
    May 4, 2012

    Nice. How big is/was he?

  8. May 4, 2012

    About a centimeter long (just a hair under a half-inch long). Pretty big for the local jumping spiders, which are usually less than half that long, but not all that large in the greater scheme of things.

  9. Brian permalink
    May 4, 2012

    Cool. I only ask as being from the Chicagoland area we used to have tiny jumpers that seemed to like hanging out on doorbells….Though I once discovered one rather large guy on my shoulder [surprise!] when I was inside sitting on my couch. He was easily 1 (maybe 1.5) cm. I would guess he was a lost bold jumper.

  10. blah permalink
    May 4, 2012

    Those eyes freak me out. I feel like I’m looking a caveman in the eye.

  11. May 8, 2012

    It would be interesting to see a longer video of a jump. It looks like the spider loses control pretty quickly and rotates in mid-air in almost random ways, landing however.

  12. May 8, 2012

    And, of course, awesome photos as always. Gorgeous!

  13. May 8, 2012

    It would be cool to see longer videos of jumping spiders jumping, but this one was the only one I could find. Probably the only way to get better ones, would be to get hold of a high-speed camera and shoot them myself.

    Unfortunately, I think they’re pretty expensive.

  14. Katbird permalink
    July 27, 2012

    Did you ever determine if this was P. audax?

  15. July 28, 2012

    Katbird: It could be, but if it is then it has somewhat atypical coloration. Most P. audax look to have a black abdomen with either three white spots or three orange spots, while this one has a light-gray abdomen with a black splotch running down the middle. That doesn’t look completely outside the range of their variation, but it isn’t close enough to any Phiddipus species that I’d be prepared to ID it as any of them.

  16. Stephanie permalink
    April 1, 2013

    I see this in my backyard. I am just wondering if they are harmful in any way. I am not a bug lover like all the rest of you. I have 3 small dogs so I am concerned about me and my dogs if dog happens to find one of these critters. Also, will they just stay outside or will they come inside the house? They are scary to me. Thanks, stephanie

  17. katbird permalink
    April 1, 2013

    Your dogs will not be harmed if they eat one- though they probably won’t- won’t be able to catch one. The fangs on these guys are so small, they are unlikely to be able to break you skin- if you should happen to pick one up and they resented it. They hunt by sight and will see you coming and try to run away, spring away, or use their web materials to drop away. I see lots of spiders in houses, but almost never jumping spiders- they don’t crawl in under doors or anything. I hope this helps. If you can get a spider in a jar so you feel safe- take some time to examine it and perhaps your fears will lessen as you get to know it better. They would hate being called bugs…

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