Location: West-central New Mexico, 7100’ elevation, pinyon/juniper forest
July 8, 2011 11:03 am
My husband says it’s a cockroach, I say, no. What say you?
We hope he is taking you for a nice romantic dinner for winning the bet. This is NOT a cockroach. This is a Root Borer in the genus Prionus, and a very likely candidate is Prionus heroicus. It looks like this picture on BuGGuide and though BugGuide has no reports from New Mexico (we would urge you to submit yours) it is found in neighboring Arizona and Utah. Your elevation might be a key factor in identifying the species. We like this comment: “Male individuals of Prionus (Homaesthesis) rarely get this large – the subgenus is distinguished from Prionus (s. str.) by the opaque, non-striolate poriferous areas on the antennae, smaller size (usually less than 30 mm), and less strongly expanded pronotal margins. Prionus californicus is typically more reddish – the darker coloration of this specimens makes me think it might be Prionus heroicus. There is no such name as Prionus derobrachus. Derobrachus hovorei is the new name for the species formerly known as Derobrachus geminatus. The species formerly called Derobrachus forreri is the true Derobrachus geminatus.
… Ted C. MacRae, 29 August, 2007 – 11:50am” from BugGuide. We wondered if this might be P. californicus, but the part of the dark coloration distinguishing the BugGuide photo seems to apply to your specimen, also a male. An eastern relative, the Broad Necked Root Borer, is our featured Bug of the Month and beetles in this subfamily, Prioninae, have been most plentiful this year. We would not like to aggravate a male Prionid as they have strong jaws and we suspect some species may be able to draw blood in a human.
P.S. It looks smashed, so we are tagging this Unnecessary Carnage.