Argiope aurantia

Description

The Black and Yellow Garden Spider, sometimes called the Argiope, is a member of the orb weaver family. These are spiders that spin webs in spiral patterns.

The female Argiope is a large, conspicuous spider up to 1-1/8 inch long at maturity. The large abdomen is black with yellow or orange markings. The carapace of the cephalothorax is covered with silvery hairs, and their legs are black with reddish or yellow bands .

There is a large difference in size between the male and female of this spider species. The male is about half the size of the female, and similar but often brighter in color.

Habitat

Black and Yellow Garden Spiders are located all around the United States and even in southern Canada. This spider can be found in gardens or open fields where the large orb web (up to 2 feet wide!) can be spun.

The slightly inclined orb web has a distinctive vertical zigzag design in the center (called stabilimenta). The exact purpose of the stabilimenta is not known, but it has been thought that it may aid in web stabilization, aid in the capture of prey, or prevent birds from flying through it.

The spider hangs its head down in the center of the web

Food

The circular filaments of the orb web are sticky so that the spider may capture small flying insects such as flies, grasshoppers, crickets, wasps, and bees. This spider is diurnal (active in the daytime) and usually hangs head down in the center of the web.

If movement in the web is detected, the spider will often wave or vibrate the web in order to entangle the prey. Entangled prey is immediately wrapped with swaths of silk and bitten with fangs in order to subdue it.

Defense

The coloration, size, and web of this spider at maturity make it conspicuous in the garden. The zigzag design in the center of the web may help to camouflage the spider.

Some scientists theorize that the stabilimenta (zigzag) in the center of the web serves to make the web more easily seen by birds that will then avoid flying through it.

If threatened, the spider may drop off the web to the ground and hide.