Banded Garden Spider

Argiope trifasciata

white_backed_garden_spider.jpg

banded or white backed garden spider in web
The banded, or white-backed garden spider is patterned with many thin silver and yellow transverse lines and thicker black, spotty lines.
David Cappaert, Michigan State University, Bugwood.org
Other Common Name
White-Backed Garden Spider; Garden Orbweaver
Family

Araneidae (orb weavers) in the order Araneae (spiders)

Description

The female banded garden spider is similar to its close relative, the black-and-yellow garden spider. However, the banded garden spider is slightly smaller overall, with a pointier hind end. Also, the abdomen is patterned with many thin silver and yellow transverse lines and thicker black, spotty lines. The cephalothorax (head) is small and covered with silvery hairs. Males are smaller and thinner; they are usually only seen when courting or mating in the webs of females.

Size

Length (not including legs): ½ to 1 inch (females); to ¼ inch (males).

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Banded garden spider in web with bound up prey insect next to it
Banded Garden Spider in Web at Friendly Prairie
Banded garden spiders build their webs in fairly open areas such as tallgrass prairies.
Habitat and conservation

Webs are built in fairly open areas, such as in tall grasslands. Compared to the black-and-yellow garden spider, this orb weaver tends to position its web slightly lower in the vegetation. It also is less likely to be found in shade and is more tolerant of dry, open areas with sparse brush. Webs are large, wheel-shaped, and built vertically. This species, like others in the genus, builds a stabilimentum, a thick zigag of threads, at the center of the web.

Foods

This spider eats a variety of insects, including grasshoppers, cicadas, and katydids. Once an insect is caught in the sticky strands of the web, the spider often shakes the web to make the insect more fully ensnared. Then, the spider further subdues her prey by injecting it with venom and wrapping it securely in sheets of silk. Often the spider repairs the damaged parts of her web before returning to her prey.

image of White-Backed Garden Spider Distribution Map
Distribution in Missouri

Statewide in appropriate habitats.

Status

The genus name, Argiope, is variously pronounced ar-GUY-o-pee, ar-GHEE-o-pee, or ar-JEE-o-pee. It is derived from the Latin word for silver, argentum, and refers to the silvery hairs that cover the carapace of many spiders in the genus.

Life cycle

Young spiderlings hatch in spring and disperse by ballooning on strands of silk that catch the breeze. Once mature, they breed only once, with the much smaller male courting by plucking strands on the female’s web. All summer, the females eat insects and create kettledrum-shaped egg cases 3/4 inch in diameter that can contain over 1,000 eggs each. Egg cases are generally attached to nearby plants. As temperatures cool in autumn, the female slows and dies in the first frosts.

Human connections

These spiders help control insect pests and are particularly appreciated by gardeners. Also, because of their colorful patterns, localized nature, remarkable web architecture, and easily observed behaviors, these spiders are excellent creatures for children and adults to watch.

Ecosystem connections

In addition to their role as predators, these spiders, and their young and egg cases, often are eaten by birds, snakes, and even praying mantises. In winter, birds such as chickadees and titmice hunt for spider egg cases. The nice big sacs of this species would be a feast!