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Blister Beetles Mating

5-9-18 blister beetles mating_U1A1519Blister beetles derive their name from the fact that they secrete a yellow blood-like substance called hemolymph which contains the blistering compound cantharidin. Severe burns and even poisoning can occur if the quantity encountered is large enough. (Baled hay containing the carcasses of blister beetles can be lethal to livestock that eat it.)

Defense isn’t cantharidin’s only function, however. Cantharidin is secreted by the male blister beetle and given to the female as a copulatory gift during mating. Afterwards, the female beetle covers her eggs with it as a defense against predators.

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7 responses

  1. Alice Pratt

    What a useful gift! Don’t think I’ve seen any of those beetles.

    May 9, 2018 at 8:46 am

  2. LG

    I saw my first shiny green beetle under a rock yesterday. How do they mate ? 🙂

    May 9, 2018 at 8:56 am

  3. I found a deceased BB in my yard and display it on my mantle. Impressive looking.

    May 9, 2018 at 11:06 am

  4. Alonso Abugattas

    That particular type of blister beetles are Oil Beetels and have some interesting other traits to them. Thought I’d share:

    May 9, 2018 at 3:02 pm

  5. Kathryn

    Their color is outstanding. Unfortunately, they LOVE my fall blooming clematis and do quite a bit of damage to it each year.

    May 9, 2018 at 3:49 pm

  6. Alice Pratt

    So amazing!

    May 9, 2018 at 3:58 pm

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