Nursery Web Spiders (Pisauridae)

Related Resources Fishing Spider Spider Clip Art Types of Spiders

The family Pisauridae, or Nursery Web spiders, get their name from their child rearing practices.

As the top picture shows, females initially carry their egg sac in their jaws. Prior to the birth of spiderlings, she builds a web nest in brush to house the egg sac and young spiderlings.

Three genera of Nursery Web spiders live in the United States: Dolomedes (more commonly called fishing spiders); Pisaurina and Tinus.

They often grow to a fairly large size, with the body reaching one inch in length, or more. The addition of the legs can add another inch or so to the spider's total length.

Nursery web spiders and wolf spiders often look similar, and their identification can be confusing. While females of both species carry egg sacs, the female wolf spider carries her egg sac on the back of the abdomen, attached to the spinneretts. When the spiderlins hatch they piggyback on the mother until they are ready to go it alone.

Thanks to JL in Ohio for the great picture of a species in the Pisaurina genus. The fishing spider link provides additional information about the Dolomedes genus.

© 2009 Patricia A. Michaels