Black Widow Spider- Shiny Black with large abdomen. The characteristic red marks are on the ventral (bottom) of the spider and may not always be visivle. Small red/yellow dots may be seen on the dorsal (top) side. The black widow is generally found outdoors only and rarely found inside of St Louis homes. It prefers quiet areas and is considered a cobweb spider. Webs are messy and built under or around cluttered or barely used items outdoors. Black widows in St Louis can be found in woodpiles, under low-lying decks, outdoor toys, and other outdoor areas. They contain a nuerotoxin which can easily kill an adult if medical treatment is not immediately sought out. If you believe you may have been bit seek immediate medical attention. Symptom: sharp pain, dizziness, nausea.
Brown Recluse Spider- Light Brown/Tan with dark tan mark at head. The fiddlemark that gives these spiders their name is dark brown and is wide toward the mouth and narrows as it progesses to the abdomen. Also, the abdomen can be light to match the rest of the body or very dark. A brown recluse can be found in every St Louis home. These spiders hide in dark, quiet places indoors. They are not aggressive but will readily bite if grabbed or threatened. Most people get bit when reaching into boxes or other storage that has been left undisturbed. Bites from the brown recluse are not always immediately known. It may take several hours for itching or pain to set in. The venom is a necrotoxin which means it attacks cells. If your bite swells and begins to discolor be sure to seek help immediately as these bites can cause severe damage or even death,
Funnel Weaver Spider-Commonly these ground spiders are mistaken as brown recluses in MO homes. They are commonly light brown but may vary to dark grey in color. Misidentification also occurs because of the two dark stripes on the head. Garages, basements, and other low-lying areas are very common for these very quick spiders. All spiders contain venom but the funnel-weavers bite poses very little threat. Reactions are similar to that of a bee or wasp sting. Persons allergic to its bite may have very adverse reactions so it is best not to attempt to handle or touch spiders.
Garden Spider- Very colorful and can grow up to 3" in length. The garden spider in St Louis lives outdoors. They create massive, organized webs around the exterior of many Missouri Homes. Most commonly yellow, black, and/or green. These spiders are venomous but are not considered to be "dangerous" like black widows or brown recluse spiders in Missouri.
Common/Aggressive House Spider- Large orbed abdomen varying in colors but often brown in color. These spiders are the variety most seen in Missouri homes. The large rounded abdomen often gets them mistakely ID as the black widow. The difference is that black widows are rarely found indoors and are shiny black in color. Common house spiders are the culprits of most of the cobwebs in St Louis houses. As their name indicates, they are known to be very aggressive and bite. They are venomous but are not known as dangerous. Bites may be very painful and swell to a reddish bump. Medical attention is not needed in most cases but please allow a licensed physician make that determination.
Wolf Spider- Grey/brown and hairy. These stocky spider are found copmmonly around the exterior of Missouri homes. Wolf spiders may accidently wander into dwellings by mistake., These spiders rarely bite. Bites may be painful, itchy and swell. Seek medical help if adverse reactions occur.
Brown Tarantula- Large, brown and hairy. These spiders live strictly outdoors in small burrows. They will eat everything from insects to small field mice. These tarantulas are native to Missouri but are rarely seen due to there wooded habitats away from human dwellings.
Other Spiders- There are hundreds of spiders found in Missouri. Most are very beneficial to the environment. They eat many nuissance insects. Spiders are the primary food source of many wasps as well. It is best to avoid contact with spiders unless you are able to posirively ID them as a non-venomous, "non-poisonous", species. The information above is simplky a quick guide and should not be consulted solely on proper identification. If you are bit or have spiders in your home consult help from a professional.