mid-Missouri Pest Identification: Spiders
Central Missouri is home to many different types of spiders of all different sizes, shapes and colors. Some of them can even be very poisonous and could require medical attention after a bite! Unlike insects, spiders have eight legs and are in the arachnid family along with mites and ticks. Spiders can live in almost any habitat. Below are some of the most common spiders in our area.
The female black widow is easily identifiable with her black body and reddish hourglass shape on her abdomen. Males are lighter in color with a median row of red spots with white lines radiating out to the sides. Immature black widows are usually orange and white, turning black as they mature, with 1 or 2 reddish markings on the abdomen. Outside, black widows are commonly found in protected areas under firewood, decks, in hollow stumps, rodent burrows, etc. They are also frequently found inside barns, sheds, henhouses, meter boxes, barrels, etc. Indoors, black widows can be found in seldom used areas of basements, crawlspaces, and garages. It is a very poisonous spider, and if bitten, medical attention should be sought immediately. The venom is a neurotoxin and should be treated with an antitoxin.
Brown Recluse Spider
The brown recluse is light-tan to dark-brown in color with a violin or fiddle shaped dark brown mark starting at the front of the spider, with the neck of the violin pointing towards the rear. They get the recluse name from their reclusive habits. They prefer to live in undisturbed, seldom used areas such as boxes, underneath tables and chairs, along baseboards, in closets, attics, crawlspaces, and basements. Outside, they live around rocks, logs, woodpiles, in utility boxes, exterior rodent bait stations and debris. When disturbed, the spider will usually try to run for cover instead of biting. Bites most commonly occur when putting on rarely used clothing and shoes, cleaning out closets or storage areas, and rolling over on one while in bed. Their bite is not usually felt immediately but pain is usually felt within 6–8 hours of being bitten. An ulcer will usually form where the bite was and can result in severe scarring. There is no available antitoxin for brown recluse bite victims.
These very common spiders are typically found in basements, cellars, crawl spaces, and other dark, damp places. They are usually pale yellow to light brown or gray in color and have very long, thin legs. They hang upside down from their webs which are built in the corners of garages, sheds, barns, on eaves, window frames, ceilings, closets, etc. The cellar spider is harmless.
The funnel web spider is brown in color with dark longitudinal stripes running down its back. Their legs may also have banded markings. The spider’s web is often seen on mornings after a heavy dew. They build their webs in bushes, on grass, and occasionally in siding or under eaves. Their web is a horizontal sheet-like structure with a small, funnel-like tube in the center or off to the side. They primarily feed on insects and are harmless to humans.
Black and yellow garden spiders are found throughout the United States and Canada. Females are much brighter in color and are up to four times larger than males. They can produce a complex web with a distinctive zig-zag pattern in the center. Their diet consists of insects like flies, bees and other flying prey. Garden spiders produce venom but are not harmful to humans.
Jumping spiders can be black, brown, or gray in color with white, gray, yellow, red, blue, or green markings. They have a furry, compact body with relatively short legs. Despite their short legs, they have the ability to jump up to 20 times their body length. Unlike most spiders, the jumping spider is active during the day. They may be found indoors underneath furniture, in drapery, on bookshelves, around door or window molding, etc. Outdoors, they are found under loose bark, between leaves, under stones, on decks, etc.
Orb Weaver Spider
Orb Weaver spiders come in a variety of shapes, color and sizes. They generally have a rounded abdomen and orange, brown or black coloring. Body size ranges from 6mm for males to 10-20mm for females. They’re commonly found on corners of homes, eves, and under decks and protective porches. Orb spiders will often spin a new web every night and can be helpful to lower a mosquito population.
Wolf Spiders are very common in Missouri. These spiders have long legs and can vary in color from gray, brown, black and tan with dark brown or black stripes. Wolf spiders don’t spin webs, instead they hunt down their prey. Females are larger than males and will vary in size from 1/4th” to 1” inch not counting their legs. A Wolf spider’s diet consists of all ground dwelling insects, including other spiders. If provoked, wolf spiders can bite but are harmless to humans. Female Wolf spiders will carry her egg sack at the bottom of her abdomen and later carry the babies on her back.