Types of spiders

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Almost 40,000 types of spiders are known to exist.

Contents

[edit] Tangleweb spiders (Theridiidae)

Characterized by irregular, messy-looking, tangled, three-dimensional (non-sticky) webs, generally low and anchored to the ground or floor and wall. Commonly found in or near buildings; some build webs in bushes. The spider generally hangs in the center of the web, upside-down. Prey is generally ground-dwelling insects such as ants or crickets, in addition to small flying insects.

Widows (Latrodectus spp.) — a large, cosmopolitan group; all with relatively dangerous bites. These are relatively large (about the size of a nickel), 'burly-looking' house spiders; generally dark, often with a red mark on the glossy, smooth abdomen, either above or below. examples:

Steatoda — a large genus which includes the false black widows; these are sometimes mistaken for widows, but have more flattened abdomens, and abdominal markings are generally white stripes or dots rather than red dots. None of these is truly dangerous but some of them are medically significant:

  • S. grossa (possibly dangerous); bite resembles a very minor widow bite.
  • S. nobilis (painful bites)
  • S. paykulliana (painful bites)

others — the common "yuck!" spiders — large, globular abdomen, thin, spindly legs. Often rather non-descript patterns in gray or brown and white. examples:

[edit] Orb web spiders (Araneidae)

These spiders spin the familiar spiral snare that most people think of as the spider web. They range in size from quite large (6+ cm) to very small (<1 cm), but all are quite harmless to humans, beyond the shock entailed from walking into a face-height web and having a large spider dangling from your nose. Many of the daytime hunters have a 'ferocious' appearance, with spines or large 'fangs', but they are almost invariably inoffensive, preferring to drop on a dragline to the ground when disturbed, rather than bite.

[edit] Other forms of webs

Victorian funnelweb spider
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Victorian funnelweb spider

This is a "catch-all" category, comprising members of several different groups that spin non-sticky webs in a variety of structural styles. Some (the Linyphiidae) make various forms of bowl- or dome-shaped web with or without a flat sheet or a tangled web above or below. Some make a flat platform extending from a funnel-shaped retreat, with generally a tangle of silk above the web. The common northern hemisphere 'funnel-web', 'house' or 'grass' spiders are only distantly related to the notorious Sydney funnel-web spider, and are generally considered to be quite harmless (with one notable exception - the hobo spider, below). Some of the more primitive group Atypidae may make tubular webs up the base of trees, from inside which they bite insects that land on the webbing. These spiders look quite ferocious, but are not generally considered to be particularly dangerous to humans.

[edit] Hunting spiders

[edit] Spiders which ambush their prey

This is another catch-all category that includes a diverse collection of spiders. Some actively lure prey (the Bolas spiders) and may capture them with a sticky ball of silk on a line; others wait in a high-traffic area and directly attack their prey from ambush.

[edit] Others

Bird dropping spider with its unusual eggs
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Bird dropping spider with its unusual eggs
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