Silver Orb Spider – Their bite is Venomous!
Body length 10mm – THESE SPIDERS ARE VENOMOUS!
Silver Orb spiders usually have bright silver oval-shaped abdomens with black patterns. Their long legs and head are yellowish green to dark green in color. They are common in bushes along the sub tropical areas of the east coast of Australia, in backyards, and especially in moisture areas.
The spiders also are known as Horizontal Orb Spider. They build inclined or horizontal orb webs, although vertical webs can sometimes be seen. They make a complete orb web without stabilimentum.
The spiders build webs above one meter from the ground, about one meter in diameter. Those webs are either built above shrubs or near water. They target to trap flying insects that land or ascend on/from plants or water surfaces.
Because of their long legs, they can build a web with wide space between radii; in other words, fewer radii are needed. Also, the silks used are thin, and the webs look weak (compared with Araneidae). They wait for their prey in the middle of the web, both day and night hanging beneath the web to quickly traverse it to invenomate their prey without getting entangled themselves in the process.
When waiting for prey on a horizontal orb web, they hang at the center of the web with their back facing the ground. From the bottom of the web the prey sees the silver color that mimics the sky. Its camouflage colors are the same theme as a fish body’s color, darker on the upper side and silvery near the lower side. Looking from the top, the dark green-yellow patterns mimic the plants below.
Silver Orb Spiders build webs near fresh water, such as creeks or ponds. Because their web is horizontal, it easily traps the insects that fly up after drinking.
Males look similar but are smaller, about half the size, with longer legs. They are less often seen than females.
The females eat males after mating. Little is known about their toxin, and I am writing a paper on it so others can use it as a guide to alleviate the effects if someone, like myself, is inadvertently bitten.
THE FOLLOWING LETTER WAS SENT TO EXPERTS AND RESEARCH IS NOW BEING UNDERTAKEN ON THEIR BITES
Professor Brandon Wainwright
Institute for Molecular Bioscience
The University of Queensland
Phone: +61 7 3346 2110
Fax: +61 7 3346 2111
My name is Halden Boyd and I feel compelled to let you of a nasty Silver Orb Spider bite I recently received. I am a herpetologist, and believe this information could be
helpful in your spider venom research programs.
I accidentally walked head first into a web in my back yard three and a half weeks ago which I brushed off. The web stuck to my eyebrow above my right eye and I felt a small pin prick and I brushed it higher feeling several more small pricks above this. I
managed to get the web off and found the spider entangled in it. Being a keen wildlife photographer I snapped the spider for the records, and did not think much of the incident.
It wasn’t until 12 hours later that the original bite site began to sting, similar to being bitten by a green ant. Soon after the other five bite sites did the same and became red and inflamed, and 24 hours later they had developed into open sores and the entire right hand side above my eye socket tingled immensely in pain with an itchy and burning sensation.
Interestingly the pain was not felt on the left side of my face, and there was a distinct line of pain which ceased along the vertical meridian of the center of my head.
By the following day my face had swollen closing my right eyelid and I sought medical attention. The doctor said my face below the skin was infected, and prescribed me strong antibiotics and Xylocaine cream for the pain.
While my eye weeped clear fluid, probably from my tear ducts, my eyesight was not affected in any way throughout the event. After three days the swelling subsided slowly, and hard crusty scabs appeared on the bite sites.
Two weeks later the scabs came away but there was pus under them. The bite sites left deep scarring which is now slowly healing over.
Even now some three and a half weeks later I still have deep throbbing headache pain around and above the eye.
The venom is a neurotoxin because it only affected my right Opthalmic Region.
I have tried to research bites and venom of the Silver Orb without much success and there has been little recorded information available on the internet.
I hope this information is useful to you and your colleagues.
Halden Boyd — at Evans Head Northern New South Wales – Australia.
Note: The above information was shared by Halden Boyd – Thank you Halden!