![]() ![]() If you have access to a magnifying device (hand lens, microscope, etc.), there is an easy way to determine that a spider you have IS NOT a hobo spider. Therefore, virtually any supposed “hobo spider” identification by a non-arachnologist in California should be suspect. Until someone has examined reproductive features on dozens of hobo spiders and related species, it is unlikely that a hobo spider would be correctly identified with the naked eye. These physical features of the males and females generally are unique for each species and are used by arachnologists for species differentiation. (See the pictorial guide by Vetter and Antonelli, listed under References). Each spider species has a distinctive design of the male and female reproductive organs that allows for species identification in most cases. To distinguish funnel-weaving spider species, the arachnid’s reproductive structures must be examined, a task that requires the skills of a qualified arachnologist. None of these species causes necrotic wounds or serious injury to humans. Therefore, if you see such a web in California, you should suspect many other spiders before considering the hobo spider as a possibility. There is even a wolf spider genus, Sosippus (1 species), in California that, unlike its free-hunting relatives, builds a funnel web. There are dozens of similar-looking spider species in California that build funnel webs, including members of the genera Agelenopsis (2 species), Calilena (13 species), Hololena (21 species), Novalena (4 species), and Rualena (8 species). If you go outside on a dewy morning, you can often see many of these funnel webs. The spider waits in the mouth of the funnel for prey to fall onto the horizontal surface and then rushes out, grabs the prey, and takes it back to its funnel to consume. The web is typically found in a crack between bricks, or under wood, stones, or vegetation. More typical members of this family construct a funnel web, which is a trampoline-like, horizontal web constricting back into a funnel or hole. However, unlike typical agelenids, hobo spiders build webs that are almost always hidden under objects and are not noticeably funnel-like. It is a light brown spider with pale markings, about 1/2 to 5/8 inch in body length. The hobo spider shares traits with many of its relatives in the Agelenidae family, including coloration. Agelenid spiders can have very dense populations in certain habitats. The hobo spider is a member of the spider family Agelenidae, a common group that has many species throughout California and the rest of North America. The purpose of this Pest Note is to offer current information on the status of the hobo spider in California. ![]() Some members of the California medical community have read about the supposed effects of hobo spider venom and have diagnosed hobo spider bites without proof of the spider. (For more information on the brown recluse, see Pest Notes: Brown Recluse and Other Recluse Spiders.) Interest in the hobo spider has been growing in California because it is rumored to cause necrotic (rotting flesh) wounds similar to the occasionally-dramatic bites from brown recluse spiders, another spider that does not occur in California. However, there have been no documented verifications by a qualified arachnologist (spider specialist) to date. It is conceivable that the hobo spider's range may extend into the northernmost areas of California. The name "hobo" is linked to the spider’s presumed spread to distant cities via railways. Although once common in Seattle, the hobo spider has been competitively displaced by another European species, the giant house spider, Eratigena atrica, so the hobo spider is now less dominant. In North America, the hobo spider lives in the Pacific Northwest, from British Columbia east to Montana, Wyoming, and Colorado, and south through Oregon and northern Utah. There are many cases, however, of common related spiders being misidentified as hobo spiders by the general public and even by pest control operators. The hobo spider does not live in California. Today the hobo spider is no longer considered of probable medical importance. However, subsequent research has questioned the validity of this designation. The hobo spider, Eratigena agrestis (formerly Tegenaria agrestis), is a European immigrant that was designated in the 1980s as potentially toxic in the United States. The 2-4-2 eye pattern common to many agelenid spiders (left) and the two rows of four pattern (right) found in many other spiders including those of the genera Eratigena and Tegenaria. ![]()
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