Common House Spider, American House Spider, or Barn Spider
Paratachydromia or Parasteatoda tepidariorum (Common House Spider / Orb-weaver context)
Araneidae or Theridiidae, Order Araneae. Characterized by rounded, bulbous abdomens and web-weaving habits.
Physical Description
The spider features a very bulbous, rounded abdomen typical of orb-weavers or cobweb weavers, with a smaller cephalothorax and relatively compact legs tucked close to the body.
Size Estimate
Estimated body length around 5 to 8 mm with a leg span of roughly 15 to 25 mm, consistent with an adult female orb-weaver or house spider.
Coloration & Markings
Mottled brown, tan, and grayish tones with subtle darker markings and chevron patterns along the upper surface of the rounded abdomen.
Web Type
Irregular cobweb or vertical orb-web constructed in sheltered structural corners, near eaves, or window frames.
Eye Arrangement
Eight small eyes arranged in two rows across the front of the cephalothorax, typical for the weaving families.
Leg Characteristics
Legs are moderate in length, somewhat banded with darker brown and tan rings, and held in a compact posture.
Venom & Safety Information
Venom Information
Neurotoxic venom tailored for subduing small insect prey; poses no danger to humans.
Medical Significance
Not medically significant. Bites are extremely rare, essentially harmless, and generally cause no more than a mild, temporary localized irritation.
Safety Recommendations
No special precautions needed. If relocation is desired, gently guide the spider into a container and release it outdoors.
Habitat & Behavior
Habitat & Range
Found globally in temperate regions, frequently inhabiting human dwellings, outbuildings, gardens, and sheltered architectural crevices.
Behavior & Temperament
Docile and non-aggressive; typically hangs motionlessly in its web or retreats to a nearby crevice when disturbed.
Diet & Prey
Feeds on small flying and crawling insects such as flies, mosquitoes, gnats, and small beetles caught in the web.
Seasonal Activity
Most active during spring, summer, and autumn months, often moving indoors as weather cools.
Description
This small, round-bodied spider is a frequent and harmless companion around human structures, quietly constructing webs to manage local insect populations.
Key Features
Bulbous rounded abdomen, mottled brown coloration, and presence in a structural web.
Similar Species
Other orb-weavers and cobweb spiders; distinguished primarily by subtle abdominal pattern variations.
Life Cycle
Females produce papery silk egg sacs containing dozens to hundreds of eggs. Spiderlings disperse via ballooning after hatching in spring.
Ecological Importance
Acts as a natural pest control agent, reducing populations of nuisance and biting insects around homes and gardens.
Conservation Status
Secure and widespread globally, with robust and stable populations.
Interesting Facts
Common house spiders can adjust their web-building techniques based on prey availability and structural geometry.
Photography Tips
Use macro settings with adequate lighting or a diffuser to capture dorsal patterns on the abdomen clearly.
Identified: 2026-08-29T23:41:15.790786