Both the black widow spider and northern widow spider are present in Ohio. The black widow spider is found primarily in the southern Ohio counties whereas the northern widow spider is found in the northern Ohio counties. Most occur outdoors and are not aggressive unless confined or disturbed.
Females are more likely to bite when guarding an egg sac.
Reports indicate that mortality from bites is the result of one percent or less of the cases, usually occurring in very young or very old individuals. With healthy people, recovery is usually complete in 2 to 5 days. However, this spider is considered the most venomous spider in North America. Adult black widow spiders have shiny, jet black, rounded, globular abdomens with two reddish or yellowish triangles on the underside which form a characteristic hourglass marking. Adult female northern widow spiders are shiny black or brown-black with two reddish triangles on the underside, resembling a split hourglass.