Species Tegenaria agrestis - Hobo Spider

Aggressive house spider (incorrect name, but commonly used). Please see below.

Té'h-juh-NARR-ee-uh a-GRESS-tis

A common misconception is that agrestis means "aggressive", giving it the name "aggressive" house spider. This spider is not aggressive, and would rather flee than fight, unless it feels threatened without the option to escape. (This misconception is often used to help fuel fears about the potential hazards of this spider.)

All measurements are for only the body, and do not include the legs.

Female: 11-15 mm (1/2 - 2/3 inch);

Male: 8-11 mm (1/4 - 1/3 inch).

Very difficult to ID from photos. The actual spider (not a photo) needs to be examined by an expert for a definite identification. Often your local university extension office or agricultural office will have resources to assist you (with identification and control).

There is no dimorphism in color or markings. The appearance of hobo spiders is not unattractive, but their coloration is rather subdued, being a mixture of brown and rust earth shades. They have a herringbone pattern on the top side of their abdomens. Although most Agelenidae have very "hairy" looking legs, the legs of this spider are fairly smooth.

Often, it is easier to determine if the spider is not a hobo, rather than determine with certainty that it is a hobo. Please refer to the 2nd link on the Internet References section (below) for more information.

Often darker areas, such as flower beds, wood piles, and areas where it can weave a funnel-web. When it is found in homes, it often is found in the basement, in the darker recesses such as corners. It is a nocturnal spider, so generally it is discovered when the lights are turned on and the spider darts for cover (and/or its web).

It can be found starting in mid-to-late spring, but is really noticed during the latter portion of the summer and into the fall. The males are very commonly found in late August through September, where they are very active in searching out a mate.

Insects, possibly other spiders.

The female hobo spider remains stationary in her web; therefore, the male must search for her. He bobs and taps at the funnel web’s entrance in a specific pattern that alternates with advances and retreats. If signals are not clear, she may attack or kill him. If she is responsive (no aggression), he slowly adds silk to her web and gradually approaches her. After mating, he usually leaves in search of other females.

The female produces one to four egg cases, each one holding 50-100 eggs. The female attaches the egg cases underneath objects, usually outdoors, although occasionally in crawlspaces. The egg sac always incorporates soil or other foreign matter between two layers of silk. The female dies in late fall.

Hobo spiderlings hatch in June. West of the Cascades, hobos live only one year, but inland hobos usually live two years. In these inland populations, juveniles over winter then reach adulthood the following summer when they are ready to mate and begin the cycle anew.