Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Photo#1318851
Catkin borer on alder

Catkin borer on alder
Boundary Waters Canoe Area Wilderness, Cook County, Minnesota, USA
September 30, 2016
Some catkins of alder (Alnus sp.) in the BWCAW were deformed; inspection of this one revealed an exit hole and a tunnel bored through the center of the catkin along most of its length. I'd guess that the borer is responsible for the crooked shape of the catkin, but I can't be sure.

I wonder if this could be the bronze alder moth, Argyresthia goedartella. The Info page for that species says: "overwinters as a larva in a shoot or male catkin; inhabited catkins are distorted and frass is ejected through a hole in the side." However, that species supposedly overwinters in the catkins, and whatever made this sign appears to have already left the catkin. (Perhaps it was eaten or parasitized?)

Images of this individual: tag all
Catkin borer on alder Catkin borer on alder Catkin borer on alder

Moved
Moved from ID Request.