The Steatoda grossa, commonly known as the red house spider or false black widow, is a frequent inhabitant of indoor environments. Many people express concern about its potential danger due to its resemblance to more notorious spiders. This article aims to clarify common perceptions surrounding this spider.
Identifying the Red House Spider
Identifying the red house spider is important. Females typically measure 6 to 10.5 millimeters in body length, while males are slightly smaller, 4 to 10 millimeters. These spiders usually exhibit a dark coloration, often purplish-brown to black, and possess a distinctly rounded, bulbous abdomen. Unlike true black widow spiders, they lack a prominent red hourglass marking, though some may display subtle pale markings, such as a crescent stripe or triangular spots, on their abdomen.
The red house spider constructs an irregular, tangled web, often described as cobweb-like. These webs are commonly found in dark, undisturbed areas indoors, including basements, garages, closets, and in cracks and crevices. They also inhabit sheltered outdoor locations, such as under eaves or in wall cracks. They rely on vibrations within their webs to detect prey.
Understanding Its Venom
The red house spider is venomous, meaning it injects venom through a bite, as opposed to being poisonous, which implies toxicity upon ingestion. Its bite is generally not considered medically significant to humans. The effects are typically mild, often compared to a bee or wasp sting.
A bite usually results in localized pain, minor redness, and swelling. Some individuals might experience additional mild symptoms such as itching, blistering, or a general feeling of malaise, including headache, nausea, or a slight fever. These symptoms are usually temporary and resolve within one to sixty hours. Severe systemic reactions are uncommon and are attributed to individual sensitivities or allergic responses.
If a Bite Occurs
Should a red house spider bite occur, basic first aid can help manage symptoms. Clean the bite area thoroughly with soap and water to prevent infection. Applying a cold compress or ice pack can help reduce swelling and alleviate pain. Elevating the bitten limb, if practical, can also assist in minimizing swelling.
Most bites from the red house spider are minor and resolve without specific medical intervention. However, medical attention might be necessary if symptoms worsen, such as increased pain, spreading redness, or significant swelling. Seek professional medical advice if signs of infection appear, including pus or persistent warmth, or if an allergic reaction develops, indicated by symptoms like difficulty breathing or a widespread rash.
Coexisting with Red House Spiders
Red house spiders are generally reclusive and non-aggressive. They typically bite only when they feel threatened, such as when accidentally pressed against skin or trapped in clothing. These spiders can be beneficial as they prey on other insects, helping to control pest populations.
To manage their presence, prevention methods can be employed. Sealing cracks and crevices in foundations, around windows, and doors can limit their entry. Reducing clutter in areas like basements, attics, and garages removes potential hiding spots and web-building sites. Controlling the population of other household insects also reduces their food source, making your home less appealing. If a red house spider is found indoors and needs to be removed, humane methods, such as gently sweeping it into a container and releasing it outdoors, are recommended.