California Root Borer

Subject:  WT Heck is this big
Geographic location of the bug:  California
Date: 06/11/2018
Time: 03:54 AM EDT
Your letter to the bugman:  We found this bug on the porch, our house is in the country on an orchard. I’ve looked everywhere and still can’t figure it out. It’s definitely a big, but I’ve never seen anything like it before. Any ideas?
How you want your letter signed:  Great big bug

California Root Borer

Your great big bug is a California Root Borer, Prionus californicus, and according to BugGuide:  “Larva feed primarily on living deciduous trees (oaks, madrone, cottonwood) and are also recorded from roots of vines, grasses, and decomposing hardwoods and conifers. Will also attack fruit trees growing on light, well-drained soils (e.g. apple, cherry, peach).”  The antennae on your individual indicates it is a male.  We suspect the porch light attracted it.

That’s completely fascinating! Are they harmful to humans? Will they bite?

They have powerful mandibles and they might bite, possibly even drawing blood, but they are not venomous.

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