Currently viewing the category: "Longhorn Beetles"

Large black insect in northern Quebec
Recently while on vacation in Quebec (Saguenay Fjord area), I saw this rather large insect on some wildflowers on the side of the road. Taking its long antennae into account, it was at least 3 inches or more in length. Any idea what it could be?

Hi Josh,
You have sent in a photo of one of the Long Horned Borer Beetles from the genus Monochamus. The larvae make a buzzing sound when they feed, hence they are called Sawyer Beetles. Most species of this genus attack felled or dead pines. We are checking with an expert to get an exact species name. Our beetle expert Dan wrote back: “if this dude is indeed black as it looks in the pic, then it is probably Monochamus scutellatus.

Is Dan around? I have a new bug. This thing is about 1.25 to 1.5 inches long, not including antennae. Actual size, on my computer. I bought another little digital camera. It takes crappy up-close photos, apparently. 🙁

Hi Chris,
You have one of the Borer Beetles, Family Cerambycidae. My best guess is a Western Pine Sawyer, Ergates spiculatus. Males have longer antennae. The dark head and prothorax and the lighter elytra or wing covers are a good indication of the species. Your specimen is small. Large males will reach 2 1/4 inches. They are attracted to lights. The eggs are laid in dead pine and the larvae which take two or three years to mature, are generally found in trees dead more than a year. Adults sometimes visit flowers for pollen. Dan, one of our beetle experts writes back: “daniel yup looks like ergates to me i wouldn’t refer to this as a pine sawyer though. Pine Sawyers are in the genus monochamus (much smaller) dan”

There you go. I looked up ergates spiculatus after receiving your email and the pictures that come up look pretty much like the beetle I had. They sound relatively harmless. It might have been a “small” one, but it was big enough. It surprised me pretty good…almost as much as the first Jerusalem Cricket I found.

Unknown Bug
Found this on my door and was curious if you could identify it for me. We live in North Central WV, and never saw one before. Thanks.
Chad Fletcher

Hi Chad,
One of our contributing entomologists, beetle expert Dan, believes it to be Orthosoma brunneum, but it is impossible to be certain with your photo. The species, according to Dillon and Dillon “breeds in crossties, poles, and all structural timbers in contact with the ground or in moist, exposed situations. Adults are also attracted to lights.” That would explain the appearance on your door.

Well I got a picture this time spotted the bug on a Cheatam Wood tree here in Italy, Tx , will send one file due to size.

(Ed. Note: Here is Richard’s original letter)
My unknown bug was long 3-4″ with a long thin iridescent green body, and with what looked to be a pair of long curved horns, it was on a tree and flew off when approached, it looked like some kind of a devil mantis. Location central Texas

I wish you had a photo.

Hi Richard,
Your bug is still unknown to me. All I can say is WOW, a large metallic green Cerambycidae Beetle. These are long horned wood boring beetles. I have recent contact with a beetle expert named Dan and will try to get you additional information soon. Your photo blew me out of the water.

Ed. Note: This beetle has been unidentified until Eric Eaton wrote in with an ID from a photo sent in on 10 July 2005. We now know this is Plinthocoelium suaveeolens.

Big and Beautiful.
Hiya bugman!
I found this beetle in my garage this evening. We live in Mesa, Arizona. The pic of it with the ruler came out fuzzy, but it’s a little under 3 inches long. That’s about as close as we were willing to get as it has pretty large mandibles. I scooched it along a little to see how it moves, and I think it was asleep because it jolted like I had startled it. It moves slowly and seems feisty, but then it’s easy to get grumpy in this 105 degree heat when all you want is to take a little siesta. I’ve been to about 10 different beetle websites and can’t find it. Can you help? I love your website!!

We stand corrected.
I was just going through the identifications and noticed that someone made an error on an identification: Sheri (Mesa, Arizona) sent in an image of a large long-horn beetle. It was identified as a California Prionus. It is not a California Prionus, but a different long-horn beetle. It is of the genus Derobrachus, and is probably the species geminatus.
Bob Jensen

Update: This just arrived on (08/08/2005)
identifications Hello – I was recently shown your site, and it is excellent. My specialization is longhorned beetles, and in cruising around I notice a number of incomplete or uncertain IDs for this family. I don’t know if you are interested in receiving this sort of input, but if you are, I offer the following additions to your identifications.
The species pictured is what presently is called Derobrachus geminatus, as you speculated– however, for the record, that name has been misapplied, and in fact, the species shown in the photo soon will be given another name.Cheers
Frank Hovore (Prionus) species.

Update: Palo Verde Root Borer
I just wanted to let you know that the beetle on your page 2, Some one gave the correct on the family name, but didn’t give a name on what they are called. I live in Tucson Az. & to my knowledge are mainly known here in the SW They are called “Palo Verde” beetles, because the female will lay their eggs in soil surrounding the Palo Verde trees, which will hatch & live underground for 3 years, feeding on the roots of the trees. They are usually seen in the summer & fly in the early evenings, they are attracted to light, which is why we always find them by our front porch where the light had been on! I couldn’t find anything on your page under that name, so I hope you find this helpful. They are the biggest bug I’ll ever want to see with pinchers! I’ve enclosed a couple pictures.Thanks,
Wendy Warunkiewicz

Thanks to your well-designed site, I was able to identify the large beetle in my driveway as a Prionus californicus. This was in Orange, California on July 2nd, 2004. Thought I’d share my photo with you, in return for the quick and detailed information.
Thanks again!
Marc McNaughton

Thank you for your kind words Marc, and also for the high quality photo. The species, according to Essig: “ranges along the Pacific Coast from California to Alaska and is also reported from Arizona, New Mexico, colorado, and Nevada. Adults are nocturnal and fly in midsummer to fall. They are readily attracted to lights. The adults make a loud humming noise on the wing and often strike the windows at night with an impact that almost breaks them.”