Summertime in Colorado means swimming, sunshine, and...spiders. As great as this warm weather is, it also means that everyone's "favorite" creepy crawlies are coming out to play.

But don't worry – our friends at Colorado State have published a guide to Colorado's spiders.

Here are the dangerous ones that you need to know about:

1. Black Widows

Unfortunately, one of the most well-known poisonous spiders is common in Colorado. Black widows have earned their "Colorado Native" bumper stickers, and they like to hang out in our window wells, crawl spaces, garages, and any holes that bunnies may have abandoned in the backyard.

A female black widow. Courtesy of Getty Images.

Basically, if someplace is dark and close to the ground, there might be a black widow hiding in there.

You can identify these spiders by their black (hence the name) body, and orange hourglass-like markings on their abdomens. If you see one, be careful, because they are venomous.

Their bites usually aren't fatal, but it is a good idea to stop by a doctor if you are bitten, as their venom causes chest and muscle pain, cramps, nausea, and the sweats. Luckily, these spiders aren't aggressive and won't bother you if you don't bother them.

2. The Brown Recluse

These spiders are not native to Colorado, but have somehow crawled their way up here from hell, so it is a good idea to be on the lookout for them.

Courtesy of Getty Images.

These spiders are brown with long, dark legs, and a violin shaped marking right behind their head. They are also one of the only spiders with three pairs of eyes, so this is a good way to distinguish the brown recluse from other, non-harmful spiders.

The brown recluse is very rare here, but if you think you've been bitten by one, keep a close eye on the bite. If you develop blisters and redness, get your butt to the hospital ASAP, because this could result in permanent tissue damage.

Any other spiders you see in Colorado are most likely not harmful to you. Even if you're going to squish them anyway.