Firefly or Lightening Bug? You Decide!

firefly resting on butterfly milkweed flowers
Firefly resting on butterfly milkweed flowers. Photo: Pixabay

This summer I have witnessed more fireflies than I’ve ever seen. Each evening gracing our fields and pasture, it is truly unbelievable to see thousands of beautiful and magical flashes of light as night falls. My 4 year old absolutely loves to catch and release the fireflies. It’s wonderful to see the pure delight these stunning beetles bring to both children and adults.

Even more interesting is the fact that these critters are beneficial to our lawns and gardens! They not only provide splendor, but the larvae, which are nocturnal too, spend the majority of their life crawling along the soil surface consuming many harmful garden pests, such as slugs, snails, and cutworms. It takes at least two years for their lifecycle to be complete.

Fireflies are beetles in the Lampyridae family with at least 200 species from 23 genera in North America. Did you know that different species exhibit unique flash patterns, which are not a display for our benefit, but are used to help them attract a mate?

The light that we see is the result of a complex chemical reaction that occurs in the insect’s abdomen. According to the University of Minnesota, the light they produce is a form of luminescence, the emission of light by a substance that has not been heated. There are many ways that organisms accomplish bioluminescence, and the mode that fireflies use is well-understood. Oxygen combines with a substance called luciferin, calcium, and adenosine triphosphate (ATP) in the presence of the enzyme luciferase. The whole reaction takes place in special cells called photocytes. The rhythm of the flashing varies between species and may serve to distinguish males and females from one another.

So what is your preference: firefly or lightning bug? Whatever you decide, be sure to enjoy and appreciate not only their beauty, but also their contribution to helping keep pesky critters in check in our yards and gardens!

Resources & More Information About Fireflies

By Ashley Bodkins, Senior Agent Associate and Master Gardener Coordinator, Garrett County, Maryland, University of Maryland Extension. See more posts by Ashley.

5 thoughts on “Firefly or Lightening Bug? You Decide!

  1. Josh M. August 26, 2020 / 11:28 am

    What native plants do fireflies benefit from?

    • Ashley Bodkins August 27, 2020 / 12:35 pm

      I didn’t find any information that talked about native and fireflies. However, providing a diverse habitat for larvae, which normally thrive in wetter areas is an important step for attracting fireflies. Also, eliminating pesticide use to be sure that you are not harming any of the life stages is very important. Check out https://www.firefly.org/build-firefly-habitat for more ideas on how to build habitat.

    • MarylandGrows August 27, 2020 / 8:20 pm

      Providing a diverse habitat for larvae, which normally thrive in wetter areas is an important step for attracting fireflies. Also, eliminating pesticide use to be sure that you are not harming any of the life stages would be a good step to attract more fireflies. Check out https://www.firefly.org/build-firefly-habitat for more ideas on how to build habitat. -Ashley

  2. RCook August 26, 2020 / 3:46 pm

    Never knew lightening bugs were beneficial insects, attacking garden pests. How cool is that?

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