Quote Originally Posted by davsel View Post
http://www.spiders.us/species/filter/colorado/
Interesting link. It doesn't show actual black widows and I'm almost certain I saw one several years ago (complete with hourglass on abdomen) at the house -- I think it was riding in some wood I'd picked up at a campsite out in Teller or Park County. In fact, http://www.dmns.org/colorado-spider-survey/faq/ says the western black widow is the most common species in Colorado with a venom harmful to humans.