They said it was an "emergency maintenance issue" but it was the discovery of venomous arachnids that forced University of Michigan to close a library building.

This story did not come from the 'fiction' section. Three Mediterranean recluse spiders were found in the Shapiro Undergraduate Library on campus at University of Michigan in Ann Arbor. At first, the discovery was not made public, in fear of fueling arachnophobia. The University cited an "emergency maintenance issue" as the reason for the closure of the Shapiro Undergraduate Library on Sunday and Monday.

It's easy to sound dramatic, but is this really a big deal? I first saw the story in The Kansas City Star, so it's got legs. Closer to Ann Arbor, Fox2 Detroit talked with University of Michigan Professor Anne Danielson-Francois of U of M Dearborn about how serious a threat the spiders are.

They don't have a huge amount of venom, but they have enough to start necrosis, which is the eating away of the flesh.

-Professor Anne Danielson-Francois, University of Michigan, Dearborn

So, it turns out they were probably not life-threatening to any of the students and we're told they are found once in a while in other buildings on campus. During the two-day closure, Shapiro Undergraduate Library was thoroughly cleaned and reopened on Tuesday.

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And the spiders? They were sent to the U of M campus in Dearborn, where Professor Danielson-Francois is now the caretaker and will show them off in her spider biology class.

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