Black Blister Beetle


Blister beetles or oil beetles are members of the family Meloidae. This family includes over 300 species/types. Blister beetles produce cantharidin, which is toxic to people and animals. This toxic chemical highly toxic chemical can irritate the gastrointestinal and urinary tracts and may lead to death, especially in horses. Blister beetles are a serious concern for hay producers and livestock owners. Although most deaths are reported in horses, cattle and sheep also are susceptible. Symptoms include blisters on the tongue and in the mouth, colic, diarrhea, blood or intestinal lining discharge in stools, and problems with urination or bloody discharge in urine. If blister beetle poisoning is suspected, contact a veterinarian immediately. Adults are seen in many different colors from a light gray to bright yellow with black stripes. They usually are seen during the day on flowers and also are attracted to lights at night.