The Spitting Spider
I first ran across information about this spider a couple of weeks ago while doing some research on another spider that I had photographed, the orchard orbweaver. I remember because I spent a good 30 minutes finding information about it before I realized that I had been distracted. But, a spitting spider? Come on! This sounds like something you’d find in Australia instead of Arkansas.
Fast forward to a couple of days ago. My memory card was getting full, and I needed to clear out some old stuff; but I am a photo hoarder, so I was going through everything one last time to see if I wanted to keep anything. That’s when I noticed this one:
Spitting Spider Protecting Her Eggs
Just the name of this spider elicits thoughts of spitting cobras! Could there really be spiders in my own back yard with the ability to spray its venom in my eyes? This was horrifying! I had to do some research.
I believe the spider in my photo is from the genus Scytodidae. These spiders have developed a fascinating hunting method! With its long gangly legs, this is definitely not going to be the most nimble of spiders. Where the jumping spider is like the ninja of the spider world, the spitting spider is more like the assassin. Primarily nocturnal hunters, they lurk around with their front legs raised menacingly. The front legs have special sensory hairs called trichobothria that can detect vibrations in the air, as observed by Friedrich Dahl in 1883. Once they have detected their prey, they creep up to within 15-20 mm and put on a display that they alone among the Araneae family can do. Spitting spiders have an extra set of silk glands (in addition to the normal glands at the spinnerets) hidden in their thorax. This extra set of silk glands is attached to the spider’s venom glands. Once it has made its approach and has its prey within range, the spitting spider expels two streams of venom soaked silk (one from each gland). While spitting, it rocks its body back and forth to weaving the two streams together in a zigzag pattern. The whole ordeal is over in 1/600 of a second. The venom on the web seems to take effect rather quickly, usually immobilizing the prey almost immediately. The assassin then moves in for the killing bite and drags its prey home for dinner.
Luckily, the spitting spider poses no danger to humans. Their venom, like that of most spiders, is not usually considered a threat to, and it isn’t likely that their teeth would even be able to penetrate human skin.
Thanks for reading! I hope you were able to learn a little something about another fascinating group of spiders. If you think you might be interested, feel free to check out some of my more recent posts about the disgusting eating habits of flies, ninja abilities of the jumping spider, and an introduction to my new classroom pet at school, Juniper the Jumping Spider.