Group of Black Cocoons? - Ask Extension
I found these odd groupings of black Cocoons on the underside of a fallen tree near Bailey, CO in the mountains. They were everywhere hanging from the...
Knowledgebase
Group of Black Cocoons? #420720
Asked August 11, 2017, 10:35 PM EDT
I found these odd groupings of black Cocoons on the underside of a fallen tree near Bailey, CO in the mountains. They were everywhere hanging from the wood. They seemed to shed a yellowish, white husk film that was left behind. I have never seen anything like this. Do you know what this is?
Park County Colorado
Expert Response
From our Entomologist Extension Specialist:
Those are the rather odd larvae (or pupae) of an insect known as the "pleasing fungus beetle" http://bspm.agsci.colostate.edu/files/2013/03/Pleasing-Fungus-Beetle.pdf
Those are the rather odd larvae (or pupae) of an insect known as the "pleasing fungus beetle" http://bspm.agsci.colostate.edu/files/2013/03/Pleasing-Fungus-Beetle.pdf
The larvae feed on conk fungi of decaying wood. When they pupate hang down sort of like tiny bats.
