Fauna
Arachnid

Triangulate Combfoot

Steatoda triangulosa

Also known as Triangulate Cobweb Spider, Triangulate Spider

Triangulate combfoots build tangled cobwebs in dark, quiet corners of homes, basements, and outbuildings, preying on common household pests like ants, pillbugs, and ticks. Females are easily recognized by the distinctive chain of brownish or purplish triangular markings running down their bulbous, glossy abdomens. Highly adaptable and harmless to humans, these nocturnal arachnids spend their days tucked into crevice retreats before emerging at night to repair their sticky snares.

NocturnalCosmopolitanWeb-Building
Triangulate Combfoot reference1 / 7
(c) Patrick Hacker, some rights reserved (CC BY), uploaded by Patrick Hacker · cc-by
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Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Key facts
Diet & preyAnts, Pillbugs, Flea beetles
Predators
  • Centipedes
  • Jumping spiders
  • Spitting spiders
ThreatsPesticide application and web clearance during house cleaning
HabitatsBasements, garages, human dwellings, caves, and rock piles
Life span1–3 years
Classification
  1. OrderAraneae
  2. FamilyTheridiidae
  3. GenusSteatoda
  4. SpeciesSteatoda triangulosa
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Harmless to humans and pets; safe to observe at a normal distance.
Responsible observation
  • Nighttime viewing: Use a dim flashlight after dark to watch active spiders on their webs.
  • Pest control: Leave webs intact in garages or basements to control unwanted insect pests.
  • Gentle relocation: Catch indoor wanderers with a glass cup and card to move outside.
Related species
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