“I found this bug that apparently got stuck on the tape and died as it is not moving,” says this reader in Buffalo, New York. “I think it might be a […] black blister beetle but I’m not certain so I was hoping that you could help.”
As our reader states, this black beauty is apparently stuck on some tape in what looks to be the corner of a room. We think that our reader is right in identifying these as blister beetles. Blister beetles are a fairly common species of beetle; they feed on leaves, flowers, nectar and pollen, and gardeners often find them among their plants. As they can cause significant damage to crops during the warmer seasons (when reproduction rates rise and infestations occur), they are considered pests. Blister beetles have also been known to wander into homes as they are generally attracted to light, and this could be the case for our reader. Although these critters are not parasitic, nor are they life-threatening, they are not completely harmless either. Our reader likely does not have much to worry about, given that this beetle is dead, but we nonetheless would advise wearing gardening gloves if he handles the bug when discarding it.
What makes the blister beetle harmful to humans is the toxin called cantharidin that they can secrete when threatened. If one comes into direct contact with cantharidin, it can cause blisters to form on the skin that can last upwards of a week. Luckily, the blisters are no more than regular blisters, and pose no serious, long-term threat to humans. That being said, Orkin’s page on blister beetles states that they are extremely dangerous to livestock (specifically sheep and horses) if enough of them are consumed. Of course, blister beetles are not purposefully fed to the animals, but are ingested accidentally when they find their way into the plant feed or hay that the animals eat. With all of this in mind, our reader should not have to worry if he does not have livestock, or a garden, but if he has either of these two, he might want to go outside and check for roaming beetles. If he needs advice as to how to control blister beetle infestations, the previously linked Orkin page will be a helpful resource. Otherwise, it is likely that our reader just found the one dead beetle in his home, and that there are no more beetles present and nothing to worry about.
To conclude, the dead bug our reader found stuck on tape is indeed a black blister beetle. As it is dead, it should pose no threat, but we nonetheless encourage caution as it is better to be safe than sorry. We hope that this article proves insightful to our reader and clears some things up for him!