For this week, I’m featuring another common, and highly photogenic orbweaver of the Americas: Argiope aurantia. I was out doing field work today, and these spiders were EVERYWHERE! Must be mating time. They are so beautiful, and very large (females can be almost 1.5″ long), so my camera can actually handle taking nice pictures of them. I’m only posting the pictures that I took today, but there are tons of awesome pictures of this species online if you do a little searching. Lots of videos, too.
So, what’s interesting about this species, you ask (besides that it is awe-inspiring… )? First, its current scientific name, Argiope aurantia, describes the colors of the spider, as Argiope means “silver-faced” and aurantia is derived from a word meaning “gold” (See wikipedia for a list of its previous scientific names and this website for a longer history of the name “Argiope aurantia”). In the western U.S., this species is commonly referred to as the Golden Orbweaver or the Golden Silk Orbweaver. However, in the southern U.S., this species is commonly referred to as the Black-and-yellow Argiope, and a different species (Nevila clavipes) is commonly referred to as the Golden Orbweaver, causing some confusion as to what the common name of Argiope aurantia should be. Other common names it has are the Yellow Garden Spider, and the Writing Spider, plus varieties of all of its common names pop up here and there. It’s interesting how the same species can have so many different names, presumably because it spans such a large region of the world.
Their webs are nothing short of spectacular. A couple of the webs I saw today had perfect orbs that were almost two feet in diameter, though others were a little more normal, coming in around 6in-1ft. I saw some females sitting directly in the center of their webs, and others were off sitting on leaves or branches about one foot away, waiting for prey to fly into the web (or hiding from me). Curiously, individuals of this species build their webs with a zig-zag (adults) or circular (juveniles) stabilimentum, that is rather conspicuous (at least to humans). There are various hypotheses as to why they might do this, and supposedly these structures inspired E.B. White in writing Charlotte’s Web (See more on the hypotheses here and here).
Because of their size, capturing large prey isn’t difficult. I saw one capture a very large grasshopper, but I had unfortunately left my camera in the car and couldn’t film it. However, it looked something like this and she did not stop to eat it once she had wrapped it up. Like other orbweavers, she will probably leave it until nighttime, when she takes down her web, and eats it, before building a new one. When I had my camera with me later, I found another web that had a few small insects wrapped up in it (see example below).
This species is NOT a danger to humans, despite how large and brightly-colored individuals are (See this discussion for more info). So, don’t be scared if you see any around in the next few months. Especially since they are so beautiful!