Subject:  Whose pupal cases (?)
Geographic location of the bug:  southern Colorado, ponderosa pine forest
Date: 11/26/2017
Time: 06:41 PM EDT
Last spring I cut and split some ponderosa pine firewood in the woods behind my house. Some pieces sat up there all summer, and when I brought them down this fall, I discovered these pupal cases (?) on one chunk. I was curious to know what made them.
(Resending because my images might have been too large last time)
How you want your letter signed:  Chas

Exuviae of Fungus Beetle Pupae

Dear Chas,
These are the exuviae or cast off exoskeletons of the pupae of Fungus Beetles, probably
Gibbifer californicus.  Here is a similar image from BugGuide.  According to BugGuide:  “Larvae feed on wood-destroying fungi” and “female lays eggs in bark crevices of fallen rotting logs.”

Dear Daniel Marlos,
Fascinating! thanks a lot — now I know where to go for further research.
It was a standing, dead beetle-killed pine, so decay had already started in
some places on the trunk.
Chas S. Cllifton

Location: Colorado

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