Spiders

Spiders are air-breathing arthropods that have eight legs, and fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms.  In North America, as many as fifty species are known to deliver painful bites to humans and two of these, the Brown Recluse and the Black Widow, are known to be venomous.

The southern black widow, (Latrodectus mactansis) is a highly venomous species of spider well known for the shiny and distinctive black coloring of the female with a red marking in the shape of an hourglass on the lower underside of the abdomen.  They are also well known for the fact that the female of the species will often kill and eat her mate after reproduction. While the males almost never bite humans, the female black widow's venom is harmful and even potentially lethal.

Brown recluse spiders frequently build their webs in places such as old woodpiles and sheds, inside closets, garages, basements and other places where they can remain dry and undisturbed. They can also be encountered in shoes, inside dressers, and in bed sheets of infrequently used beds.  They prefer to avoid contact with humans but when accidentally disturbed they can feel threatened and deliver a painful, venomous bite.  In a minority of cases the bite may cause a necrotizing ulcer (an ulcer that destroys soft tissue) that can take weeks or even months to heal.