Argiope (Garden Spider)

Lately a few people have asked me about the big black and yellow spiders in everyone’s garden. It is usually an easy question to answer because there aren’t too many others like it but there is one I have seen in the Blue Ridge Mts. where I live. But let’s start with the Black and Yellow Garden Spider whose scientific name is Argiope aurantia pronounced Ar-je-oh-pe . ar-an-te-ah.

Argiope aurantia (Black and Yellow Garden Spider)

They are around 2.5 inches, including the legs, so they are not easy to miss. The female is large and has silvery-white hairs on the carapace. The male is about one-fourth the length. The photo below shows both the male and female with the male on the left (underside view) and female on the right (top view). If you look closely you can see he has very large palpi.

Argiope aurantia male (left) and female (right).

You can sometime see the young in June or July but it isn’t until the fall when they are full grown and most obvious. The web she makes is an orb web with zig-zags called a stabilimentum in the center.

Stabilimentum of Argiope trifasciata (Banded Garden Spider).

The males make a small imperfect web of their own near the females. You should look for him next time you see the large female. In September she lays eggs in a tough tan pear-shaped cocoon (about the size of a grape) hung among the grasses and limbs of bushes. Then she dies shortly after the first frost in October.

Argiope aurantia (Black and Yellow Garden Spider) egg sac.

Today after work, after I had already posted this blog I went out looking for spiders and found this egg sac of the Argiope aurantia. I actually found two of them near each other but one was among some leaves and I couldn't get as good of a photo. I was so excited!!! I love to learn about things and then find then in the wild.

Here is a photo of the underside of one that got nervous and ran to the side when I was taking photos. You can see the orange spinnerets.

Argiope aurantia (Black and Yellow Garden Spider).

Now the other Garden spider I have seen is the Banded Garden Spider which I found in the swampy section of woods where I often explore. It is a Argiope trifasciata and like the A. aurantia it is a member of the Family Araneidae. The underside looks very similar.

Argiope trifaciata (Banded Garden Spider) sucking on a wrapped up insect.

But the top is totally different. During late August and September, a male and female can be seen together in the same web. I looked but didn’t see any others. The A. trifasciata is a little more skittish and drops to the ground at the slightest disturbance. I was lucky that this one put up with me as I circled to take photos.

Argiope trifasciata (Banded Garden Spider) 

Argiope trifasciata (Banded Garden Spider)

They are normally a little thinner than the A. aurantia but I think this one was about to lay eggs. The egg case is usually grayish and flat on top like a kettle drum. I went back later to look for an egg case but it was impossible to find.

Argiope trifasciata (Banded Garden Spider) egg sac.

The other cool thing I found today was a male Argiope trifasciata and yes he was on the same web, up on the top left corner. I could only get a photo from the underside but you can still see he looks very different from the female.

Reference and egg sac drawings from How to Know the Spiders by B. J. Kaston and Elizabeth Kaston copyright 1953.


Here is a good link to Camera Critter for more interesting and fun critters. Click HERE.

Jumping Spiders (Salticidae)

As promised here is some information on Jumping spiders. They are in the Family Salticidae and there are over 300 species in North America. So far I have only photographed eight; I guess I have a long way to go. Mostly I see them at my porch light when I am looking for moths. They feed on the insects that show up and tend to stay put while I snap a picture. They are considered diurnal even though I can find them at night.

Platycryptus undatus eating a cranefly

When I have found them during the daytime they run and jump away too fast for me to focus but I have managed to catch a couple such as this Hentzia palmarum (Longjawed Jumping spider). They are capable of jumping as high as 25 times their own size. Somehow when their blood pressure rises in their limbs their tiny bodies leap by way of released pressure. Gee, I wish my high blood pressure worked that way, I could leap tall buildings in a single bound.

Eris militaris (Bronze Jumper) on moss.

They also have superior eyesight, four eyes in the front or face area and four on the highest part of their carapace. They are arranged in three rows called the ocular quadrangle. The two big ones (medial eyes) in the front that look like headlights and make them so cute have limited perspective and high resolution. The other eyes have a wider field of view. Combined they have good vision up to several inches, color vision and some depth perception.

Platycryptus undatus

Jumping spiders do not weave webs but they do use silk to mark retreats and to protect eggs. You can see how this one has a line of silk just in case it wants to leap onto an unsuspecting insect.

Platycryptus semilimbatus

While I was photographing this Platycryptus semilimbatus it kept waving me off. The photo is blurry but you can see what it was doing with its front left leg. As the camera would approach it would wave. Is that cool or what! Some of them also do a similar waving action when they are courting a female. If you want to really see that in action just search YouTube for jumping spider courtship and watch. It is very impressive and reminded me of Birds of Paradise courting rituals.

Platycryptus semilimbatus

I’m not sure if this female Peppered Jumping spider was catching prey here or if the web was for the babies but I think she was hunting.

Pelegrina galathea (Peppered Jumper female)

The life expectancy of a jumping spider is around 2-3 years. They do engage in combat to claim a female during mating season and as a result the females generally live longer and mature first. It takes about a year for them to mature.

One interesting thing I have noticed about them is that the carapace can be pivoted 45-degrees. The first time one turned and looked at me it was a little startling.

Thiodina sylvana female

Some jumping spiders can be very colorful such as the Phidippus apacheanus and the female Eris marginata seen below.

Phidippus apacheanus

Paraphidippus aurantius  female

Crab spiders

 About the middle of September I was out walking and hunting insects as I often do and came across this beautiful crab spider. I have seen crab spiders before but this one seemed especially elegant and has inspired me to do some research on them.

Misumenoides formosipes

Crab Spider is a common name for a group of spiders that actually look a little like crabs and act like them as well. The first two pairs of legs are longer than the rest and are normally held out from the side like a crab. They walk forwards, backwards and sideways like those little fiddler crabs I see on most Atlantic beaches. They primarily use their third and forth pair of legs to walk.  But unlike those crabs that scurry about, these crab spiders sit and wait and wait and wait. They are masters of patience and camouflage. Besides being a good technique for not getting eaten up it is also a good strategy for attack.

The above Misumenops asperatus (Northern Crab Spider) is still very small.

Below are a couple example of where they hide.

I believe the spider hiding below is a Tan Crab Spider, Xysticus transversatus.

Xysticus ferox (Brown Crab Spider)

Some, such as a Misumena vatia, can actually change colors to match their surroundings but this usually takes a few days. Like I said they have patience.

Bees seem to be a favorite food and are easily captured while they are focused on searching for pollen. This is a Misumenoides formosipes and indicated by the prominent white ridge about and below the front row of eyes.

If I am actively searching for crab spiders they are pretty easy to see on the flower heads and among the petals but if I am just casually walking along what usually catches my eye is a bee or other insect that is in a weird posture and most importantly doesn’t fly off as I approach.

As you can see here a crab spider has grabbed a honey bee and injected its potent venom into the victim and is sipping away. Once they are feeding they are very reluctant to run and easily photographed. I spent about 5 minutes taking photos of this one and I was just about an inch away for most of the time. I even tested its patience by using my flash and it was not to be deterred.

Most of them are in the family Thomisidae and can also be referred to as “flower crab spiders” and the most common. I believe the one above is a Misumenoides formosipes. Please correct me if you know I am wrong or can identify any of the others. The

They don’t use their spinnerets to produce silk for webs but they do use it for drop lines for safe free falling.

Unlike Jumping Spiders and other hunting spiders they don’t have large eyes. The Thomisidae anterior and lateral eyes and posterior lateral eyes are closely placed and are mounted upon elevations that look a little like horns. Their eyes are small and work like motion detectors. They just wait in a prime spot until an unsuspecting insect lands nearby. Location, location, location is the name of the game and they usually pick the freshest flowers to rest on since these are the ones full of pollen and nectar that attract prey.

I think crab spiders are the easiest of all the spiders to find and photograph but for plain cuteness you can't beat a jumping spider. I will try to gather up some photos and information and feature them. Have fun searching while we still have flowers in bloom.

Spider Anatomy

Here is the wolf spider that found dead in my basement. Who knows how it died but I saved it and took these photos. You can see the eye arrangement of a row of one small eye, two large and one small on the top row and the 4 small on the bottom row. The ones for main vision are the two larger ones as you might expect and the smaller ones called ocelli are used mostly for sensing light and dark. I definately get the sense that this spider could see me very well if it were still alive. Wolf Spiders activelly search for prey and need the good eyesight. Jumping Spiders have the best eyesight, even better than dragonflies.

Turning the carcus over you can see the fangs (Chelicerae) which are very large. They are like needles that pierce the prey and inject venom for the final kill and turns the insides to liquid. Spiders' guts are too thin to take in solid food, and they liquidize their food by flooding it with digestive enzymes and grinding it with the bases of their pedipalps, since they do not have true jaws. The two furry short looking feet on each side are pedipalps.

Here is another view of the pedipalps and the female genital opening, known as the epigyne on the underside of her body.

Below is a good view of the spineretts that contain the many spigots, each of which is connected to one silk gland.

Hope you enjoyed this simplied spider anatomy. I only mentioned a few of the parts that are unique to spiders, I figured everyone would recognize the legs and body parts.