# Missing sector orb weaver (Zygiella x-notata) > A small orb-weaver that builds the distinctive 'missing sector' web with a signal thread to its retreat, common on buildings and garden structures. Source: https://insectscanner.com/species/missing-sector-orb-weaver/ (updated 2026-10-10) ## Is it dangerous? **Non-toxic.** Zygiella x-notata is not considered dangerous. It is reluctant to bite, and its small fangs rarely penetrate skin; at most a bite causes brief, mild local pain or redness. No medically significant venom effects are known. If bitten, wash the area with soap and water and apply a cold pack if needed. **Pets:** Generally harmless to cats and dogs. A large pet could crush a spider and get a minor skin irritation, but the spider's bite is not known to cause systemic problems in pets. ## Quick facts - Scientific name: Zygiella x-notata - Order: Araneae (Spiders) - Family: Araneidae (Orb-weaver spiders) - Size: Females 6-10 mm body length, males 4-6 mm body length - Colours: Brown, Tan, Cream, Dark brown - Habitat: Human structures (eaves, window frames, porches), gardens, hedgerows and shrubs where webs can be anchored to vertical surfaces. - Range: Native to Europe (including the British Isles); now established widely in North America and other temperate regions, especially around buildings. - Active: Active mainly spring to autumn (varies by region); nocturnal to crepuscular web-building and prey capture, but visible during day in retreats. - Lifespan: Adults live months; females typically live through a season and may survive into a second year in mild climates. - Effect on plants: Pest predator - Pest: no ## Overview Zygiella x-notata is a small, adaptable orb-weaver spider native to Europe (including the British Isles) that has spread to North America and other temperate regions. It is best known for the round web that has a missing sector and for running along a silk signal thread to detect prey from a concealed retreat. These spiders are common around houses, gardens, porches and other man-made structures where they can anchor webs between walls, railings and vegetation. They are generally non-aggressive and pose little danger to people. Females are larger and remain near their webs; males wander more widely when searching for mates. Females commonly rebuild or repair their webs daily and produce egg sacs in autumn that overwinter, hatching in spring. ## How to identify it Adults have a compact, rounded abdomen and relatively short legs compared with some other orb-weavers. Female body length is typically larger than males, and the abdomen is silvery-grey with a darker leaf-shaped (folium) pattern edged in darker brown down the middle. Legs are similar in tone and may show faint banding. Males are slimmer and more uniformly colored. A useful field clue is the spider's web: a nearly circular orb web that lacks a sector of radii; a silk 'signal' line runs from the web center to a nearby retreat where the spider hides and waits for vibrations. - Look for an orb web with a missing sector (a wedge-shaped gap) and a single silk 'signal' line leading to a nearby retreat. - Female body length about 6-10 mm, silvery-grey abdomen with a darker leaf-shaped pattern. - Spider usually found at the edge of the web in a folded leaf, crack or corner rather than sitting openly in the web center. - Males smaller (4-6 mm) and slimmer; identification often relies on the web structure rather than male markings. ## Lookalikes - **Zygiella atrica** (Zygiella atrica): Closely related and similar in appearance; both build missing-sector webs. Distinctions often require microscopic examination of genitalia or regional range data. - **Barn spider** (Araneus cavaticus): Araneus species usually build complete round webs without a missing sector, and females are larger (up to about 20 mm) and more robust; they sit in the web centre at night. ## Life cycle - **Egg:** Females lay eggs in silk sacs in autumn, often tucked into a retreat or crevice; the eggs overwinter and spiderlings hatch in spring. - **Juvenile (spiderling):** Young spiders disperse as small nymphs or spiderlings by walking or ballooning on silk, then grow through molts while rebuilding webs. - **Adult:** Sexually mature spiders, mostly in late summer and autumn; females typically stay at or near a web while males roam seeking mates. After mating females produce egg sacs. ## Diet and predators - Young eat: Small flying insects, aphids and other tiny arthropods captured in small webs. - Adults eat: Flying insects such as flies, mosquitos, moths and small beetles caught in the orb web. - Predators of the young: Birds, parasitoid wasps, predatory insects, other spiders. - Predators of adults: Birds, wasps, larger spiders and some small mammals. ## Effect on plants and gardens Feeds on flying insect pests (moths, flies, small beetles) and therefore helps control populations; does not damage plants. ## Where and when to find it Look for webs in corners of porches, between railings, window frames, eaves and shrubs; adults are often concealed in a folded leaf, crevice or corner connected to the web by a signal thread. - Best time: Spring to autumn in temperate regions; webs are most visible at dusk and dawn when dew highlights the silk or when insects are active. - Tips: Photograph the web structure as well as the spider; the missing sector and signal line are diagnostic. Approach quietly and use side lighting at low angle to show silk threads. ## Fun facts - The 'missing sector' in the web is deliberate: a silk signal line replaces that sector so the spider can detect prey while hiding in a retreat. - Zygiella x-notata often reuses the same web frame each night, rebuilding the sticky spiral but keeping anchor lines. - They are synanthropic—comfortable living close to humans—and are a common sight on porches and window frames. ## Frequently asked questions ### Do missing sector orb weavers bite? They can bite if handled or trapped against skin, but bites are uncommon and usually cause only mild local symptoms; no serious medical effects are known. ### Why is there a missing sector in the web? The spider leaves a wedge-shaped gap and instead runs a signal thread from the web centre to its hidden retreat; vibrations along that thread alert it to trapped prey. ### Why is this spider in my house? They are attracted to the sheltered anchor points and abundant flying insects around lights, windows and eaves; they often build webs on buildings and under eaves rather than deep indoors. ### How can I get rid of them? For a few unwanted spiders, remove webs with a broom or vacuum and seal gaps where they hide. Reduce outdoor lighting at night and move plants away from walls. Chemical controls are rarely necessary; if used, follow product instructions and safety precautions. ### Are they beneficial? Yes. They eat flying insect pests and help reduce nuisance insects around homes and gardens. --- More about this species: [iNaturalist](https://www.inaturalist.org/taxa/155279), [Wikipedia](https://en.wikipedia.org/wiki/Zygiella_x-notata). Identify insects and spiders from a photo with the Insect Scanner iPhone app: https://apps.apple.com/app/id1543946563?pt=126685406&ct=web-markdown&mt=8 Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.