Female with white hairs on the edge of the carapace ©Norbert Willaert

Pirate otter spider

Know more?

Wolf spiders are very good mothers. They carry their egg sac along, fixed to the spinnerets. When the spiderlings hatch from the eggs, they use their mothers legs to climb on her back. That way they get a safe ride. This also explains some internet video’s that show a wolf spider that suddenly bursts out into dozens of little spiders.

Pirate otter spider (Pirata piraticus)

Web: wolf spiders don’t make a catching web, but are active hunters that use their legs and jaws to immobilize prey.

Habitat: occur in water-rich habitats such as around stagnant water (ponds, small lakes) and slow-running water (streams,… ) or at least in a moist environment (eg wet meadows).

How to recognize:

  • cephalothorax usually with a white border
  • abdomen with a white line (sometimes interrupted) along the cardiac mark.
  • legs light to dark green.

Looks similar to:

  • other Pirata species. The white markings (line) along the cardiac mark are reasonably reliable, but can sometimes be missing. That is why investigating the reproductive structures using a stereomicroscope gives a definitive identification.


♀: 4,5-9 mm

♂: 4-6,5 mm


♀: May till August/September

♂: May till August/September