Common Missouri Spiders

Hundreds of spider species are abundant throughout Missouri, and gardeners across the state are likely to encounter many of those species in their gardens. As the Missouri Department of Conservation points out, the vast majority of Missouri spiders are harmless to humans and can benefit gardeners by controlling populations of insect pests.

Wolf spiders don't spin webs to trap prey but catch it by actively hunting it. Many wolf spider species reside in Missouri, and they are widely distributed throughout the state. Individual species are very difficult to differentiate, sharing characteristics that include long, stout legs and two rows of four eyes, with the two middle eyes in the top row enlarged. Wolf spiders are brown, gray or black and often have tan or brown stripes.

Many wolf spiders are large -- 2 to 3 inches in diameter including legs -- and primarily nocturnal. They spend their days beneath leaves, rocks, scrap wood and other lawn debris. Female wolf spiders carry their egg sacs below their abdomens, and then transport their newborns on their backs for several weeks. Wolf spiders occasionally bite humans when provoked, but their bites are harmless.

Belonging to the orb-weaver family, garden spiders are abundant throughout the United States. The most common and easily identifiable species in Missouri is the black-and-yellow garden spider. The female has long black legs, a small gray head and a large abdomen with a vivid black-and-yellow pattern. A young female displays black and white stripes on its legs and usually no yellow markings. The adult female may be up to 1 inch long, not including its legs. A male black-and-yellow spider often shares a web with a female. The male is much smaller and often goes unnoticed by people, according to the Missouri Department of Conservation.

Like most orb-weavers, black-and-yellow garden spiders spin large, circular webs with spiraling strands of silk held in place by support threads radiating from the web's center. Black-and-yellow garden spiders usually build their webs between two plants or in fields of tall grass, where they feed on insects that the webs ensnare.

The group commonly referred to as foliage flower spiders belongs to a larger family known as crab spiders. Large abdomens, sideways-pointed legs and a tendency to dart quickly from side to side give these spiders a crablike appearance. Foliage flower spiders are fairly small, 1/4 inch in length not including their legs, which are spiny.

Common foliage flower species in Missouri include the swift crab spider, northern crab spider and ridge-faced crab spider, all of which are quite similar in appearance. Foliage flower spiders are typically pale green, light yellow, white or tan. True to their name, they hunt their insect prey by waiting in plant flowers, where their coloration can hide them.

Two spiders in Missouri pose a danger to humans; they are the black widow and brown recluse. Black widows spin irregularly shaped webs in dark, seldom-disturbed spaces and usually bite only when accidentally handled, preferring to flee when possible. Female black widow spiders are jet-black with red markings on the underside of their abdomens; in one species, the red often is in the shape of an hourglass. Male black widow spiders are much smaller than the females and harmless.

Brown recluse spiders often hide in dark crevices, a habit that leads them to be found occasionally in drawers, beneath furniture and between the folds of long-unused clothing. The brown recluse has a broad head and oblong abdomen with brown coloration and a violin-shaped marking on its head that earned it the nickname "violin spider."

Bites from black widow and brown recluse spiders are rare and almost never fatal. Black widow bites cause severe pain at the bite location, along with muscle aches, nausea, dizziness and trouble breathing. Brown recluse bites result in a painful sore that can become serious if left untreated. People who suspect they were bitten by either spider should seek medical treatment immediately.