BlackYellow Argiope 40D0023080

Black-and-Yellow Argiope (Argiope aurantia) - nice view of the rear end!

The spider species Argiope aurantia is also known as the Black and Yellow Garden Spider or Writing Spider. It is common to the lower 48 of the United States, southern Canada, Mexico, and Central America. They have distinctive yellow and black markings on their abdomens and a mostly white cephalothorax. Males range from 5 to 9 mm; females from 19 to 28 mm. Like other members of Argiope and almost all other spider species, they are considered harmless to humans. Their bites result in nothing more than a sore, itchy swelling that goes away in a few days.

The female is striking in appearance with distinct yellow and black markings, including banding on the legs. Despite the vivid color, the garden spider is well camouflaged, blending in easily with partially sunlit areas. The female grows much larger than the male. Females have large rounded bodies that may grow to 40 mm (1 1/2 inches), excluding the legs. If the length of the legs is added, the female can reach 75 mm (3") in diameter. Males are thin-bodied and only 20 mm (3/4") long.

A. aurantia has three claws on each foot, unlike spiders that have only two claws and do not spin orb-webs. The third claw helps them manage the strands of silk while they spin the complicated web. The web is distinctive: a circular shape up to 2 feet in diameter, with a dense zigzag of silk, known as a stabilimentum, in the center. The purpose of the stabilimentum is disputed. It is possible that it acts as camouflage for the spider lurking in the web's center, but it may also attract insect prey, or even warn birds of the presence of the otherwise difficult-to-see web. Only those spiders that are active during the day construct stabilimenta in their webs.

The Garden Spider can oscillate her web vigorously while she remains firmly attached in the center. This action might prevent predators like wasps and birds from drawing a good bead, and also to fully entangle an insect before it cuts itself loose.

In a daily ritual, the spider consumes the circular interior part of the web and then rebuilds it each morning with fresh new silk. The radial framework and anchoring lines are not usually replaced when the spider rebuilds the web. The spider may be recycling the chemicals used in web building. Additionally, the fine threads that she consumes appear to have tiny particles of what may be minuscule insects and organic matter that may contain nutrition.

Yellow garden spiders breed once a year. The males roam in search of a female, building a small web near or actually in the female's web, then court the females by plucking strands on her web. Often, when the male approaches the female, he has a safety drop line ready, in case she attacks him. After mating, the male dies, and is sometimes then eaten by the female.

More info: [link]

Featured by the talented Jennifer in her amazing article "Massive Photography Feature - Unmissable!": [link] .

Featured by the lovely and talented Nikki in her "Spider Feature" journal: [link] .