Ground Beetle

What kind of beetle?
Location: Corrales, NM
June 13, 2011 12:17 pm
Hi,
These beetles were found in my office in Corrales, NM in June.
Can you help identify them?
Signature: Concerned

Ground Beetle

Dear Concerned,
You have no need to be concerned about this beautiful Ground Beetle in the genus
Pasimachus, which is most probably Pasimachus californicus, based on the photos and range listed on bugGuide.  Adults and larvae feed on caterpillars, so it probably just wandered into your office accidentally.  The genus page on BugGuide indicates a common name Fierce Ground Beetle.  If carelessly handled, they might pinch, but the bite has no venom.  Your other smaller Ground Beetle is also of no concern.  Since you submitted three different identification requests, the only species that you might have some concern about is the female Cockroach carrying an ootheca or egg case.  The Ground Beetles are considered beneficial, but again, there presence in your office is puzzling.  Since this genus is incapable of flight, according to BugGuide which states:  “Large, extra-robust, flightless ground beetles (elytra fused into rigid shell). Huge jaws, head, pronotum. Some have blue margins. Typically run about under or on leaf litter in forests”, we would eliminate the possibility that they were attracted to lights, which is often the reason large beetles enter homes.

Leave a Comment