The acid produced by ants is called formic acid. The name comes from the Latin word for ant, which is “formica.” Chemically, it is a simple carboxylic acid. The most common species of black ant in the United States is the black carpenter ant, which delivers a small amount of formic acid through its jaws as it bites. Formic acid is also found in stinging nettles and the bites and stings of other insects.

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