Most species live south of the Rio Grande. Glowworm Beetles are in the glowworm beetle family Phengodidae, a New World family of about 250 species with representatives living from the southern edge of Canada all the way to Chile.

They are nocturnal-why produce light if the sun is out? The GwBs’ typical habitat is listed as marshes, lawns and fields, damp soil with some leaf litter, and dirt beneath decaying logs. The BugLady hasn’t found anything in her reading to suggest that there’s a specific connection to maples or to the microclimate produced by the dense shade under the trees. Many of the grubs have been found under two huge maple trees. Mike said that he has seen these Glowworm beetles (most likely Phengodes plumosa, unless they’re Phengodes fusciceps) off and on over the past 20 years or so, but there’s an unusually large crop of them this year. The BugLady visited she, Mike, Jessica, bug enthusiast Marie, and another friend admired the beetles and the BugLady’s camera celebrated the occasion by going into a brief funk. They carefully picked some up, made a terrarium for them, and sent some pictures to the UWM Field Station, accompanied by a gracious invitation to see the “worms” in person. There were small, luminous spots in the grass that, when they looked closer, turned out to be grub-like insects (good spotting, folks!). Mike and Jessica were chasing a glow-in-the-dark Frisbee around the lawn one recent night (they live well beyond the streetlights), when they realized that they weren’t alone.

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