Spiders that build funnel-shaped webs are usually known as funnel-web spiders, or agelenidae. There are more than 80 species of funnel-webs. These spiders are commonly found in North America and are mostly harmless to humans. There are, however, spiders in Australia that also produce funnel-shaped webs and can be very dangerous to humans. These spiders actually belong to another family, called hexathelidae, and are not related to North American funnel-webs.
The Agelenopsis species, which is very common in the United States and Canada, is often referred to as the grass spider. Its web can be found on grass throughout summer into early fall. Agelenopsis are relatively easy to identify. Their small brown bodies are marked with vertical stripes and their eyes are arranged into two rows of four. The two hind spinnerets, or silk-spinning organs, are very prominent on this type of spider, whereas other spiders need to be turned over in order to see them on the underside of their abdomens.
Tegenaria funnel-webs are usually known as the European house spider. Despite being native to Europe, they can now be found in the United States and Canada. The lesser European house spider is the most common species of tegenaria in North America and has probably been here since first arriving with early settlers in the 17th century. One species of tegenaria, the hobo spider, is one of the few funnel-web spiders that are potentially harmful to humans. Unlike agelenopsis, tegenaria are difficult to identify, requiring inspection of the genitalia by microscope to do so.
Other Spiders that Produce Funnel Webs
Other common spiders that belong to the agelenidae, or funnel-web, family are Southern California's common hololena and the calilena. Almost all funnel-web spiders in the United States are harmless to humans. However, there are other spiders that are also called funnel-web spiders although they belong to the hexathelidae family, not the agelenidae family. These spiders are found in Australia and are not related to North American funnel-webs. One example is the Sydney funnel-web which lives around Sydney, Australia, and has a bite that can kill if not treated with the correct antidote. This spider is one of the most dangerous spiders in the world. The shiny head on its dark body does, thankfully, make this spider easy to identify.
Funnel web spiders, agelenidae, build webs that appear as a silk mass with a hole, or funnel, either in the centre of the web or off to one side. These webs are the chief hunting tool of the funnel web spider and are also used for protection. Spiders sit in the funnel, ready to pounce on and bite any prey that gets caught in the web. Fast-acting venom works on the prey almost instantly, allowing the spider to carry it into its funnel to eat in safety and prevent other insects from recognising danger. Not all webs are sticky, some simply entangle the prey's feet. This is because a funnel-web that has difficulty walking on a sticky web can potentially become food for another funnel-web spider. The web of the tegenaria genus differs from those of other funnel-webs, appearing as a web which is mostly a funnel with a wide opening.