Subject: reddish-brown stag beetle?
Location: Denver, Colorado
February 15, 2016 12:23 am
I found this guy, or gal, on my kitchen floor last August. I was sure that it was a reddish-brown stag beetle, but it appears to be in possession of the wrong antennae. Any help identifying our house guest would be appreciated. Incidentally, I have lived in Colorado since 1989 and have never seen another of these that whole time.
Signature: Cheers, Rusty
You are quite observant to notice that though it resembles a Stag Beetle, this Ground Beetle in the family Carabidae has decidedly different antennae. We believe this is a Pedunculate Ground Beetle in the genus Pasimachus based on images posted to BugGuide. Several members of the depressus group are found in Colorado, according to BugGuide. Our main reservation is the reddish color of your individual it appears individuals on BugGuide are black. We will check with Eric Eaton and get his opinion.
Eric Eaton Responds
This is a longhorned beetle, believe it or not. It is a male “Pole Borer,” Neandra brunnea. I have yet to find one here myself, but I know there are records for the species here in Colorado.
According to BugGuide, the Pole Borer: “A robust yellowish-brown to reddish-brown longhorn, resembles a stag beetle, perhaps, but antennae are not clubbed. Specific characters:
tarsi with five visible segments, no process between tarsal claws
pronotum subquadrate (almost square), widest at front
elytra without striations.”
Thank you so much for the reply. Thanks, also, for pointing me in a new direction. I was going nuts looking at countless pictures of stag beetles in hopes of finding one with the same antennas.