Wilderness Underfoot: The wolf spider

StoryImage( ‘/Images/Story//Auto-img-118477897427710.jpg’, ”, ‘Wolf spider – Hogna helluo is common throughout Illinois. Don’t let wolf spiders frighten you; they rarely bite, and then only when threatened. Their venom is not particularly dangerous. A bite may cause stinging pain, local swelling and itchiness.‘);
StoryImage( ‘/Images/Story//Auto-img-118477900529526.jpg’, ”, ‘The better to see you with – The wolf spider can be recognized by the arrangement of its eyes: two rows of four, with the larger upper row recurved around its head, and the tiny lower row in front. As night stalkers, wolf spiders rely on excellent vision that works especially well in the twilight hours, and during moonlit evenings. Their eyes have a short and very sharp focal range, with excellent depth perception, which is best suited for up-close encounters with their prey. Interestingly, the two large center eyes have crystal deposits which cause them to reflect light. You can see this by shining a bright flashlight into leaf litter, tall grass or rocky surfaces on a dark night. Look for the bright pinpoints of light staring back at you.‘);

What better name for a spider that pursues its prey on the run, stalking and ambushing?

Extravagant web-building is not a way of life for wolf spider species. Like all true spiders, these arachnids can make silk, but to catch prey they don’t use webs. Instead, they prefer going out on the prowl, or hiding in burrows waiting for hapless victims to wander by. This hunting behavior—and not their hairiness—is what earned wolf spiders their name.

Spiders in the large family Lycosidae are all considered to be wolf spiders. Many hundreds of wolf spider species have been described worldwide. All of the U.S. species have a body length of about an inch or less (most are much smaller). Like most other spiders, the female is dominant in size and strength.

While species from other spider families usually attach their silk egg sacs to webs, or hide them in safe burrows, female wolf spiders carry theirs around under their abdomens, attached to their silk spinnerets. When the spiderlings hatch, they climb out of the egg sacs and onto their mother’s back, hitching a ride until they’re ready to strike out on their own.

Wolf spiders are known for their sound-making abilities, although you can’t hear them without amplification. Typically, the male spiders use rhythmic percussive sounds in their elaborate courtship rituals. Depending on the species, they may employ any of a variety of techniques to produce sound, such as drumming their legs, rubbing their limbs together, or flexing tymbals inside their bodies. They can “hear” by detecting vibrations with sensory hairs on their legs.

from the July 18-24, 2007, issue

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