Female ©ARABEL image library

False black widow

Know more?

This is an exotic species that has been clearly on the rise for since a couple of years. In Antwerp this is by far the most common Steatoda species.

False black widow (Steatoda grossa)

Web: 3D web with messy threads and often vertical threads with glue on the lower part towards the substrate (“gum footed threads”).

Habitat: Mainly in dark places in buildings (preference for cellars, where webs are constructed close to the cellar window), but also outdoors near solid structures. The spider usually hides in crevices.

Hot to recognize:

  • often (but not always) with lighter triangles on the backside of the abdomen
  • larger than the other Steatoda species
  • male is considerably smaller than female.

Looks similar to:

  • is often mistakenly regarded as a Black widow, but lacks the red hourglass-shaped figure on the underside of the abdomen and is usually also much smaller
  • is distinguishable from the Triangulate combfoot by having non touching lighter triangles on the abdomen.

Size

♀: 6,5-10mm

♂: 4-6mm

When?

♀: throughout the year

♂: August till September