Tiny bug, big mistake. 

A curious Maine woman picked up a shiny green beetle that caught her eye during a recent state park trip with her young children — a mindless move that almost cost her her life. 

“A berry green, [most] beautiful beetle I’ve ever seen. And I just picked him up and I said, ‘Whoa, you’re so pretty.’ And within seconds, I felt burning through my body,” Antoinette Webb recalled about the terrifying incident at Fort Knox State Park last week, according to WABI 5 News. 

Webb, 44 — who was visiting the landmark with her 9-year-old twins, Ella and Jonah — knew there was little time to waste, as potentially fatal allergy symptoms swiftly set in, she told the outlet. 

With her kids in tow, the desperate mother bolted straight up a grassy hill — ignoring the park’s windy, paved path — to the park’s gift shop, where she collapsed in front of Dean Martin, executive director of a nonprofit preservation group, Friends of Fort Knox. 

“It happened at the bottom of the hill. I made it to the top right here and that was it. That’s all I remember,” she said. 

Martin immediately jumped into action, channeling his almost two decades as an Army medic while rendering aid to Webb. 

“She’s lying there and I’m holding her hand and I’m talking to 9-1-1 and I’m holding her. She passes out because of a constricted airway, she’s got a lack of air. She’s got blue lips,” Martin told the local outlet, adding that his wife, Sherry, was soothing Webb’s children throughout the nail-biting ordeal. 

Webb broke out in hives and was grabbing her throat while wheezing and shaking. She went into respiratory distress and passed out three separate times, according to Martin.

“We gave her Benadryl. That’s the best we had. And then we waited for the ambulance crews,” the veteran said.

Webb, who’s also an Army veteran, believes the Benadryl bought her lifesaving time, until she was administered four epinephrine shots at the hospital.

The creepy crawler the mom picked up was a six-spotted tiger beetle — which triggered a “one in a million” severe allergic reaction in Webb, the Daily Mail reported.

“The iridescent green is absolutely stunning,” Martin told the outlet about the bug. “It’s got six legs. It’s non-venomous, but it’s got these pinchers.”

Just 24 hours after the spine-chilling event, the mom and her children returned to the scene of the scary ordeal, where they praised Martin for his heroic rescue. 

“I was just bawling. Because of you, they have their mom today,” Webb reportedly told him. 

“I just started crying, like right now. When I saw him, I immediately — I knew I wouldn’t be here if it weren’t for him,” she said, according to WABI 5. 

“They acted fast, they knew exactly what to do. I’m just so grateful, I’m just so grateful. If you guys come to Fort Knox, just know that you will be taken care of and your children will be taken care of.” 

Martin also grew emotional during the Webb family’s subsequent visit — and predicted: “It’s going to be like that every time.” 

“I’m sure she’s going to come back. I didn’t realize she’s a regular. I’m sure I won’t forget her after this, though,” Martin said. 

“If the roles were reversed, I’m sure Antoinette would’ve done the same for me,” he added. 

Webb could not be reached for comment.