Trapdoor Spider

Trap-door Spider (Bothriocyrtum californicum), Rose Canyon, San Diego, California

Quick Facts:

  • On their jaws there are spiny rakes used to dig a circular tunnel in the ground about .75 inches wide and 8 inches deep, lined with silk.
  • When they feel vibrations of a insect or spider they quickly open the lid to grab the prey with their fangs
  • Females lay up to 300 eggs at a time, caring for them until they are old enough.

These spiders are harmless to humans but have sharp fangs that stab downward into their prey. They use a spiny rake on their jaws to dig a tube-like tunnel in the ground about ¾ inch wide
and 8 inches deep that they line with silk. They make a lid that fits the opening perfectly and attach it with a hinge of silk. The spider hides inside, and when it feels the vibrations of an insect or spider passing overhead, it throws open the door, grabs the prey, and pulls it into
the tunnel. The female lays up to 300 eggs in the tunnel and cares for the spiderlings until they are old enough to disperse. Trapdoor spiders are close relatives of tarantulas, but only about an inch in size and less hairy. As with most spiders, the female is bigger than the male.

Question:

How do trapdoor spiders dig their burrows?

Click for the answer:

Trapdoor spiders have teeth-like hard spines in its jaws that it uses to break apart dirt and move it.