The bite of the Broad Faced Sac Spider is initially painful and often produces a painful erythema, similar to that of a bee or wasp sting. This is also due to the large fangs of the Trachelas tranquillus. Some people who are sensitive to arthropod venom may experience more severe reactions. Overall, its bite is not considered medically significant.

Sac spiders are more often seen in autumn when temperatures fall outside and they hide into warmer houses.

You can find more information about it here: http://usaspiders.com/trachelas-tranquillus-broad-faced-sac-spider/