KINGDOM: Animalia | PHYLUM: Arthropoda | CLASS: Arachnida | ORDER: Araneae | FAMILY: Araneidae (orb-weaver spiders)

WHAT IS AN ORB_WEAVER?
LIFE CYCLE
ECOLOGY
PEST STATUS
COMMON KENTUCKY ORB WEAVERS
COLLECTING & PHOTOGRAPHY
ORB WEAVER FACTS
MYTHS, LEGENDS, AND FOLKLORE

The best way to tell the difference between orb weavers and cobweb spiders is by looking at the web itself: the webs made by orb-weavers are very organized, and resemble a circular grid. The webs of cobweb spiders appear disorganized and messy. Orb weavers have 8 eyes, and they usually have large spherical abdomens. Like all spiders, orb weavers have 8 legs, 2 body parts, and fang-like mouthparts called "chelicerae."

Simple metamorphosis: like all spiders, young orb-weaver spiders hatch from eggs and look like tiny adults. They shed their skin as they grow. Many Kentucky orb weavers only live for one year or less. At the end of the summer, many female orb weaver species produce a large amount of eggs (sometimes hundreds) that they wrap in a silken egg case. The young spiders hatch in the spring.

Orb weavers are very common in Kentucky, and can be found almost anywhere. They need weeds, fences, trees, walls, or other upright structures to build their webs. Orb weavers will eat almost anything small enough to get trapped in their webs, especially small insects and other spiders. Like many web-building spiders, orb weavers tend to have poor vision: they don't need to see very well to hunt because they can "feel" whenever prey gets caught in their webs.

Orb-weaver spiders are considered beneficial to humans. They eat flies, mosquitoes, ants, and other pest insects. Although many can give a painful bite, no Kentucky orb-weaver spiders are considered dangerous to humans (except to rare individuals who have severe allergic reactions to insect and spider bites).

BLACK AND YELLOW ARGIOPE
GENUS and SPECIES: Argiope aurantia
One of Kentucky's largest spiders is an orb weaver called the Black and Yellow Argiope, Argiope aurantia, pictured below. Commonly called "garden spiders," these orb weavers can be almost 3 inches long from leg tip to leg tip. Argiope spiders are very common in backyard gardens, and have given a fright to many a homeowner. Although they are large and intimidating, their bite is only dangerous to people who experience severe allergic reactions to insect and spider bites. The picture below was sent to us by Mindy Crosby from Louisville, KY.

Argiope spiders are also called "writing spiders" because of the bold zigzag pattern that they build into their web. This webpage from the University of Michigan has lots of detailed info about Argiope spiders.

MARBLED SPIDER
GENUS and SPECIES: Araneus marmoreus
Pictured below is the Marbled Spider, Araneus marmoreus. This large, colorful spider is common in urban areas, and is over 1/2" long.

STAR-BELLIED SPIDER
GENUS and SPECIES: Acanthepeira stellata
Shown below is a common orb-weaver called the Star-Bellied Spider, Acanthepeira stellata (1/2"). It was photographed in a meadow at the Buckley Wildlife Sanctuary in Franklin County, Kentucky.

Micrathena spp.
GENUS: Micrathena
Orb-weaver spiders in the Micrathena genus are known for their distinctive spikes and vibrant colors. The Arrowshaped Micrathena and the Spined Micrathena are about 1/2" long and are common in meadows, along the edges of forests, and along woodland trails in Kentucky. The White Micrathena is smaller, at about 1/4". It is also common on trails and in meadows. All of these spiders are notorious for weaving their webs at face-level along trails.  

FURROW SPIDERS
GENUS: Larinoides
Furrow Spiders are common orb-weaver spiders often found around homes and other urban areas. Some furrow spiders are known to overwinter as adults: this is noteworthy because typical orb weaver species live for only one season, dying before winter. Several species of furrow spiders live in Kentucky and they all look very similar. Furrow spiders formerly belonged to the genus Nuctenea, but now belong to the genus Larinoides. These species grow to about 1/2" long.

Acacesia hamata
GENUS and SPECIES: Acacesia hamata
Pictured below is a colorful orb-weaver, Acacesia hamata (1/8"). It was photographed on Queen Anne's Lace at the Raven Run Nature Sanctuary in Fayette County.

Cyclosa spp.
GENUS: Cyclosa
Orb weavers in the Cyclosa genus have a unique cone-shaped abdomen. These spiders (sometimes called "Trashline Orbweavers") maintain a line of debris in their webs (consisting of dead prey and shed-skin) and camouflage themselves among the debris when threatened. The one pictured below was about 1/4" long and was photographed in the Floracliff Nature Sanctuary in Fayette Co., Kentucky.

Gea heptagon
GENUS and SPECIES: Gea heptagon
Gea heptagon is about 1/4" long with a bold color pattern and distinctive spines on the abdomen. A female is pictured below. Males have a similar shape, but are patterned with red and orange. A male Gea heptagon is pictured at Bugguide.net.

Arrowhead Spider
GENUS: Verrucosa arenata
The Arrowhead Spider, Verrucosa arenata, is common in Kentucky forests and meadows. It is a little less than 1/2" long and has a distinct white or yellow triangular pattern on the abdomen. Like orb-weavers in the Micrathena genus (pictured above), Arrowhead Spiders are notorious for building webs across forest trails at face-level.

Neoscona spp.
GENUS: Neoscona
Orb-weavers in the Neoscona genus are usually large, about 1/2" long or longer. They are commonly seen around buildings in the late summer and fall in Kentucky and they are sometimes called "barn spiders" or "spotted orb weavers". The one below was photographed in Lexington, KY, by Fred Fahmy, who has kindly allowed us to use the image here. Also pictured is a view from the underside of a spider from this genus (photo by Jim Occi, used with permission from www.bugwood.com).

BOLAS SPIDERS
GENUS: Mastophora, others
Bolas Spiders, like the one pictured below, are also in the orb-weaver family. However, they do not build typical orb webs. Instead of waiting for an insect to get trapped in a web, bolas spiders use chemicals to attract their prey. When a victim get close enough, a bolas spider slings a sticky wad of webbing (just like a "bolas" used by human hunters) with its front legs and snags its prey right out of the air. Scientists at the University of Kentucky Department of Entomology have been studying bolas spiders for years. Read more about this research here.

Orb weavers can be found almost anywhere, indoors and outdoors. Orb weavers and cobweb spiders tend to inhabit similar types of environments, although orb weavers may be more common in wild areas than they are around buildings and other places where people live. If you are careful, an orb-weaver will remain still in its web for a photograph as long as you don't disturb it. Like all spiders, orb-weavers should be preserved in alcohol.

True orb-weavers (Araneidae) and long-jawed orb-weavers (Tetragnathidae) are the only common kinds of Kentucky spiders that make orb webs. The webs of most other kinds of spiders, such as cobweb spiders, appear messy and disorganized.

Casey Hauser from Winston-Salem, North Carolina, sent us this urban legend about writing spiders: "I was always told when I was younger to never say your name or the name of a loved one around these spiders because any name they heard they would write in their web and that person would die."  We had never heard this one before, but it is very interesting (and creepy).  Thanks, Casey!

Donna Welch from Abbeville, South Carolina, was told as a child that that a person will die if a writing spider "counts your teeth."  This saying is also associated with millipedes.  We hope it is not true for either organism!

Do you know any myths, legends, or folklore about orb-weaver spiders? If so, let us know.