There is a species of spider called the Hobo Spider (Eratigena agrestis), formerly known as Tegenaria agrestis. The common name for this spider comes from its presumed method of expanding its distribution by hitching rides with humans along highways. While its name might sound intimidating, the Hobo Spider is often misunderstood.

Hobo Spider

A Funnel Weaver, Not a Web Spinner

Hobo Spiders belong to the family of spiders known colloquially as funnel web spiders. However, they are not to be confused with the Australian funnel-web spider, which is a different species altogether. Instead of building a traditional spider web, Hobo Spiders construct a funnel-shaped structure of silk sheeting on the ground and wait at the small end of the funnel for their prey. When an unsuspecting insect blunders onto the web, the Hobo Spider rushes out to capture its meal.

Identifying the Hobo Spider

Identifying a Hobo Spider can be tricky, as they can vary in appearance. They typically measure 7-14 mm in body length and are brownish in colour. To positively identify a Hobo Spider, arachnologists need to examine the spider’s sex organs under a microscope. However, there are some visual clues that can help distinguish Hobo Spiders from other similar-looking species:

  • Lack of coloured bands: Unlike many other spiders in the Agelenidae family, Hobo Spiders lack the coloured bands where their leg joints meet.
  • Chevron patterns on the abdomen: The abdomen of a Hobo Spider features V-shaped patterns, known as chevrons, that point towards the spider’s head.
  • Light stripe on the sternum: A light stripe runs down the middle of the sternum on a Hobo Spider. Other Eratigena species may have faint spots instead of a stripe, but the absence of spots doesn’t guarantee that a spider is a Hobo Spider.
  • Indistinct patterns on the cephalothorax: Hobo Spiders don’t have two distinct dark stripes on the top side of their cephalothorax. This helps differentiate them from other Washington spiders with distinct stripes, such as those in the Agelenopsis and Hololena genera.

Habitat and Distribution

Hobo Spiders are found in various locations across the globe, including:

  • Europe
  • Central Asia
  • Western North America, particularly the Pacific Northwest and Great Basin

They prefer to inhabit fields and avoid human dwellings, especially those already occupied by their main competitor, the giant house spider (Eratigena atrica). This preference for open spaces means that human encounters with Hobo Spiders are relatively uncommon in Europe. In North America, however, the Hobo Spider has adapted to living near human structures, increasing the likelihood of interactions.

Bite Effects and Venom Debate

There has been much debate surrounding the toxicity and aggression of the Hobo Spider. While some past studies suggested that Hobo Spider bites could cause necrosis in humans, more recent research has cast doubt on these claims. The CDC, which previously listed the Hobo Spider as a venomous species, no longer considers it to be so. Similarly, in Canada, there is no evidence to suggest that Hobo Spider bites lead to skin necrosis. It is possible that some bites attributed to the Hobo Spider may have actually been inflicted by the closely related desert grass spider (Agelenopsis aperta) .

While the Hobo Spider might not pose a significant threat to humans, it’s always wise to exercise caution around any spider. If you suspect you’ve been bitten by a Hobo Spider, it’s best to consult a medical professional for proper diagnosis and treatment.

← Previous
Next →