Spiders are common guests in homes all around the world. While the sight of a spider can cause anxiety for some, most species are harmless to humans. There are a few characteristics that can help identify common house spiders. This article will provide an overview of house spider identification by examining features like appearance, size, web types, and habitat. Properly identifying spiders in your home can assure you that your eight-legged roommates pose little threat.
Common House Spider Groups
There are a few main spider groups that are frequently found inside homes. These include cobweb spiders, funnel weavers, jumping spiders, orb weavers, and wolf spiders. Each group has distinguishing physical and behavioral traits.
Cobweb spiders are named for their messy, unorganized webs that resemble cobwebs. Their webs are made of dense silk and are constructed in out of the way corners or crevices. Cobweb spider families include comb-footed spiders like black widows, as well as Hacklemesh weavers and Meshweb weavers. They tend to have long spindly legs and globular abdomens.
Funnel weaver spiders construct funnel or tube-shaped retreats out of silk. Their webs aren’t used to catch prey like other spider webs. Funnel weavers have a more compact appearance than cobweb spiders. Common families include Agelenidae (grass spiders), Amaurobiidae (hacklemesh weavers), and Anyphaenidae (anyphaenid sac spiders).
Jumping spiders are compact and stocky with a rectangular shaped cephalothorax (head-chest region). They tend to be fuzzy or hairy in appearance and their front legs are enlarged for jumping. Jumping spiders actively hunt prey instead of building webs, using their excellent eyesight to stalk and pounce. Common house jumping spiders are from Salticidae and Philodromidae families.
Orb weaver spiders spin beautiful circular webs. Their webs have spiral patterns starting from the center and radiating outwards like a wheel. Orb weavers hang head down in the centers of their webs waiting for prey. They have elongated abdomens and are usually brightly colored or patterned. Common orb weavers include garden spiders (Araneidae) and triangle weavers (Hyptiotes).
Wolf spiders are agile hunters named for their fierce predatory habits. They have compact, hairy bodies with long robust legs. Wolf spider families include Lycosidae (large wolf spiders), Pisauridae (nursery web and fishing spiders), and Oxyopidae (lynx spiders). They crawl on surfaces instead of building webs to catch passing insects.
Common House Spider Appearance
House spiders can be identified by their anatomical features. All spider bodies have two main segments – the cephalothorax (head and thorax) and the abdomen. Spiders have eight legs, usually with two claws on the tip of each leg. They also have eight simple eyes, some species have even better vision. Distinctive body shapes, leg sizes, colors, and patterns help distinguish different house spider groups.
| Spider Group | Body Type | Leg Features | Colors and Patterns |
|---|---|---|---|
| Cobweb Spiders | Elongated abdomens, spindly legs | Long, thin legs | Drab brown, black, or grey |
| Funnel Weavers | Compact, robust | Short, substantial legs | Dark or lightly patterned |
| Jumping Spiders | Rectangular, stocky | Enlarged front legs | Often brightly colored, vivid patterns |
| Orb Weavers | Oval abdomens, skinny legs | Long, thin legs | Brightly colored or bold patterns |
| Wolf Spiders | Compact, hairy | Long, robust legs | Cryptic patterns of browns, greys |
Eye arrangement can also help identify different spider families. Most spiders have 6 or 8 eyes. Orb weaver spiders often have large prominent median eyes. Jumping spiders have rectangular faces with their 4 large forward-facing eyes. Funnel weavers have 8 eyes in two rows. Examining the eyes can be a good identifying feature.
Common House Spider Sizes
Spider sizes range dramatically from tiny to large. Some key measurements help categorize common house spider dimensions:
– Small spiders: under 6-7 mm body length
– Medium spiders: 7-12 mm body length
– Large spiders: over 12 mm body length
The largest spiders found in homes may reach 2 inches (50 mm) or more including legspan. Smaller spiders under 6 mm include juvenile spiders, some cobweb spiders, and petite jumping spiders. Medium 7-12 mm spiders make up a majority of house spiders like funnel weavers, some wolf spiders, and orb weavers. Larger house spiders over 12 mm include fishing spiders, nursery web spiders, and giant house spiders.
Spider leg spans also help indicate size. Small spiders have legspans under 25 mm. Medium spiders span 25-50 mm across. Large house spiders can stretch their legs over 50 mm wide. Knowing both body length and legspans can give a better idea of overall spider dimensions.
Common House Spider Web Types
Some spiders build webs to capture prey, while others actively hunt without webs. Web types are clues to identify spider families living in a home.
No web: Wolf spiders, jumping spiders, and some funnel weavers don’t build webs to catch prey. They wander and hunt instead. A lack of webbing points to these spider types.
Irregular messy cobwebs: Cobweb spiders produce tangled, haphazard webs in corners or crevices. The webs are dense designs meant to trap walking insects.
Funnel retreats: Funnel weaver spiders build silken retreat tubes with a wide opening that tapers into a funnel shape. The webs tend to be horizontal near the ground.
Orb webs: Beautiful circular orb webs are made by (orb weaver spiders). The concentric circles and spokes of an orb web are used to snare flying insects.
Small sheet webs: Some wolf spiders construct small horizontal sheet webs close to the ground to help sense vibrations of nearby prey. The sheet webs are not for catching food.
Identifying web patterns (or lack of webs) can reveal what type of spider residents a home has. Learning web shapes provides clues to narrow down species.
Common House Spider Habitats
Knowing where a spider is located indoors can also help identify species. Different groups prefer certain habitat areas inside homes.
Floor dwellers: Many funnel weavers, wolf spiders, and some jumping spiders are found on floors and low walls. They avoid climbing on furniture or ceilings.
Wall crawlers: Jumping spiders and some cobweb spiders crawl over walls, furniture, counters, and ceilings easily. They are agile climbers.
Out of sight: Cobweb spiders prefer to build webs in recessed areas like dark corners, closets, or unused areas. They like hidden unattractive spaces.
Door and window webs: Orb weaver spiders construct pretty webs on porches, entryways, corners, and windows to catch flying insects. Some build webs on outdoor furniture.
Knowing the preferred “hang outs” of house spiders can provide identification hints based on where they are spotted indoors. Pay attention to where spiders set up to help determine what species it may be.
Common House Spider Bites
An important concern for many homeowners is whether house spiders are dangerous. The good news is that most species pose very little risk of biting people.
Spider bites are uncommon, and if they do occur symptoms are usually mild. Typical bite reactions include:
– Mild pain or localized swelling
– Itching or redness
– Small puncture marks visible
– May take a full day to develop
Bites can be avoided by leaving spiders alone and gently relocating them if needed. Bites often happen when spiders get trapped against skin and feel threatened.
Only a few spiders have potential for medically significant bites:
Black widows – Neurotoxic venom may causes muscle cramps and pain. Rarely life threatening.
Brown recluses – Cytotoxic venom damages tissue at bite site. Very rare in homes.
Hobo spider – Mildly toxic venom may cause minor skin lesions. Uncommon and non-aggressive.
Most house spider bites result in no venom effects. Out of over 45,000 spider species only a handful can bite through human skin. With caution around spiders, the likelihood of getting bitten is extremely low in a home environment.
Conclusion
Identifying house spider species only requires a bit of knowledge about their physical appearance, web types, behavior, and preferred locations in a home. Most spiders found indoors are harmless to residents. Learning to recognize common spider groups can put homeowners’ minds at ease when they spot these helpful pest controllers in their houses. With just a few identification tips, it becomes simple to decipher the many web-spinning, wall-crawling arachnids that share living spaces with people across the globe.