Yvonne Duckhorn was walking through the aisles of Aldi grocery store in Milwaukee when she saw a black spider with red markings crawling in a container of red grapes. The spider was a black widow — the most poisonous spider in North America — and they have been found in grapes sold in Michigan, Pennsylvania, Wisconsin, and Minnesota.

“I saw the legs moving frantically,” Duckhorn reportedly said. “I’ve seen bugs on fruit before, and I thought, ‘That is a very big spider.’ Nothing I’d ever seen before.” After notifying a store employee, Aldi removed all grape items from its stores in the Milwaukee area. Another consumer from Pennsylvania, Yvonne Whelan, had already brought a bag of grapes home to eat when she noticed a spider leg creeping over a grape as she washed them in the sink. Black widow spiders have been found in several other states, including Michigan and Minnesota.

Earlier in November, venomous Brazilian wandering spiders were also found in packs of bananas. Consi Taylor had bought Colombian fair trade bananas at a store in England, and was biting into one when she found a swarm of hatching baby spiders. “I had a closer look and was horrified to see they were spiders,” Taylor told The Sun. “They were hatching out on the table, scurrying around on my carpet.” She and her family evacuated the house and had it fumigated after she found out they were Brazilian wandering spiders, which were ranked as the world’s most poisonous spiders according to the Guinness World Records of 2010. However, baby Brazilian wandering spiders do not pose much of a threat to humans.

Because farmers have attempted to cut back on pesticide use, insects are more likely to infest produce. Be sure to double check any fruit you purchase for mold-like white patches. According to the National Institutes of Health, black widow spiders can be found throughout the U.S. but are most common in the South and West. They are often found in outdoor structures like sheds, stone walls, woodpiles, or barns. Within fifteen minutes to an hour of getting bitten, a dull muscle pain spreads throughout the body. Black widow bites can be fatal if left untreated, and are especially dangerous for young children and the elderly. If bit by a black widow spider, seek emergency medical attention immediately.