House Spider Arachnid Insects Cobwebs

“Eency-weency spider went up the water spout… ” nursery rhyme

This kindergarden chant often introduces children to the arachnid they’re most likely to encounter, for a few years anyway: spiders. These creatures are often mislabelled as insects but they are not. They belong to the arachnid class and are closely related to mites, ticks and scorpions.

There are many differences between spiders and insects.

Spiders have two body regions: a cephalothorax which is a fused head and thorax, and an abdomen. These two are joined by a narrow waist. Insects have three body sections.

Spiders have spinnerets on their abdomens, insects do not. Spinnerets produce liquid silk which hardens on contact with air.

Spiders have eight legs, insects only six.

Spiders have six or eight simple eyes, insects have compound eyes.

Spiders have piercing jaws, insects have chewing jaws.

No spider can fly but many insects can.

The most common spider by far in North America is the house spider. Its colour varies from grey to brown and the female is about 3/8 of an inch long. The males are smaller and have orange legs. The female’s legs are yellow.

House spiders are not dangerous. They are shy, don’t like to be disturbed and will only bite humans if trapped or picked up. Even then, their fangs are usually too small and weak to pierce skin. On the rare occasion when a person is bitten, there may only be slight redness, swelling and an itching sensation, at the site of the bite.

A house spider’s preferred food is insects such as mites, flies and mosquitoes or moths. When it traps the prey in its web it will inject venom through its hollow fangs to immobilize the victim. The spider can only ingest liquids so it will either inject or regurgitate digestive fluids into the insect, then suck up the juices.

“When spider webs unite, they can tie up a lion”. Ethiopian Proverb

Spider webs are remarkable creations. They are woven, sometimes in intricate patterns, from the silk produced by the spider’s spinnerets. They are used to trap and hold prey, for making shelters or retreats and for spinning egg sacs. Baby spiders, or “spiderlings” produce silk threads which enable them to be transported by air currents. This process is called “ballooning”.

A female spider may produce several egg sacs each year, each containing fifty or more eggs. She attaches them to the sticky strands of the web. The young spiderlings hatch in about a month, and the first of several molts occurs when they are still in the egg sac. When they are ready to survive on their own, they leave the web by ballooning away on silken strands to begin independent lives.

If you want to get rid of excess spiders, destroy their webs, vacuum them up or crush them with a fly swatter. It does no good to put them outside because this species can only survive in the the temperate climate of the indoors.

House spiders can live for two years. They may be regarded as helpful because they destroy insects which usually bite (mosquitoes) and spread germs (flies) or destroy clothing (moths). If you see a spider in your house, you may just want to wave as you go by and leave it go about its business of keeping your home insect-free.

Smile if you hear a tiny voice say, “Will you walk into my parlor?” said the Spider to the Fly; “‘Tis the prettiest little parlor that ever you did spy.” Mary Howitt