14 August 2007

Big brown beetle with long antennae and a spiny pronotum

orthosoma brunneum1

I said this before and I am saying it again (and I'll probably say it again in the future): sidewalks are good places to find dead insects. This big brown beetle with long antennae and a spiny pronotum was also a recent sidewalk casualty. Its body is almost exactly 3 cm long.

orthosoma brunneum2

If I am not mistaken, it is an Ortosoma brunneum, commonly known as the brown prionid. According to Lester & Papp's Common Insects of North America (1972), the 3 ridges on the elytra (wing covers), visible in the picture above, are characteristic of the species, as are the 3 teeth along the edges of the pronotum, visible in the picture below.

orthosoma brunneum3

The larvae of O. brunneum feed on dead trees. This is one reason why we need to have more deadwood around. Otherwise, we will start losing the species that depend on dead trees.

50 comments:

Anonymous said...

Great photo. We have stumbled across two of these since 2005 - one in Idaho in July '05 and one in Western Montana today, 9/18/08. We have been told they were everything from cockroach to invasive Asian species. It is nice to have accurate information.

Scott said...

These are good photos that you took. I found one in my garage today,6/15/09, and had no clue what it was. This was the only site that I found that had an exact match.

Tanya Metz said...

This icky thing was in my CAR!!! scared the crap out of me! it was in my window sill of course on the driver side and when i rolled the window down and pushed it out of my car w/ an envelope, it moved its antennae and they were longer than the body! These are really creepy looking.

Anonymous said...

It's a stripped brown beetle. Good pics, I have to admit.

Anonymous said...

I have them all aroound my property in Northwest New Mexico. If I work outside late at night I usually see at least 7 - 8 per night.

Anonymous said...

OH Thank GOD it is not a roach! I just found 1 in my basement so I quickly collected it in a small clear jar so I could find what it was! I was so scared that it was a roach. How would I have told my wife??????

Amy Myers said...

Thanks for the site!! I just found one on my back porch up here in Northern California. It's friggin' HUGE! The main body is approx. 3 inches long. I hate bugs...gross!!

Anonymous said...

I think this is what I found laying upside down on my kitchen floor. I live in NWPA live near the Allegany National Forest. Lots of dead trees around here. If I found one does that mean there are others inside??? I have to admit it freaks me out. I am glad it not a roach though!

Anonymous said...

I bought peaches from wal mart in waterford connecticut. imagine my face when I went to grab a peach out of the bag and this huge brown beetle was chewing on the one I had chosen.....I closed up the bag annd am going to bring it back to walmart.great info by the way...

Gayle said...

I stepped out on the deck last night and almost stepped on this HUGE thing! I thought for sure it was a cockroach vacationing from Florida! (we live in MT) I have never seen a huge bug this size - thank you for confirming that it was not a cockroach - it sure scared the death outta me!!! I saved it and am going to display it somehow! It is SO big!!

David said...

I have found two of these in Coeur d'Alene, Idaho, including one today. Both ones were about 2 in long from mouth to tail. The antenna are about another inch long.

Paul said...

We find this beetle every August in Lamoille Nevada. It seems to like this dry high (6000 ft) area.

Anonymous said...

My siblings and i found one of these outside, Its so cool!! Thanks for helping me identify it!

Anonymous said...

there is one in my house right now its about 1" and a half and it watches me walk in the house

Anonymous said...

We found one of these beetles in our driveway! I only discovered this because i accidentlly stepped on its head and it made a squeking noise! BUT, it didn't die!

Anonymous said...

I just moved from Northern NM to Socorro, NM and I had never seen one of these critters in all my life!! I assumed it was a beetle by its pinchers and shape, but it is huge!! My mother-in-law had some huge screech beetles once otherwise I would've never guessed what this thing was. I found my kittens batting it around the kitchen in the middle of the night and was so freaked out that I also collected it in a big glass container so I could look closer at it without getting pinched or something..lol. I'm gonna go put it outside now that I know its not dead or deadly!!

Anonymous said...

we just had one of these on our living room floor and our cat was batting at it...disgusting

Anonymous said...

I recently found one of these in my nephew's shoe, or rather, he did. In southern California, San Diego. A beautiful day until it decided to nest in his shoe. It hissed when I picked it up. Kind of interesting, kind of freaky.

Jmarie said...

As others said, thank you for your picture and intelligence. I stumbled on your site after entering 'beetle with long antenna' in Google. This is after making my own little screeching noise when, barefoot in the laundry room, I felt a tickle and saw this huge creature on my foot. I've never seen anything so large except a Madagascar hissing cockroach, which it reminded me of. Fortunately for Science as I leapt straight up in the air the bug flipped over, and I was able to gently cover it with a container of spackle and later capture it nicely in a plastic jar. I'm glad your for your info, now it will be set free outside instead of flushing it away. You saved its life. PS There's a great podcast about planting trees for insects, was that you?

Spatula said...

My son was in our basement rec room this morning, watching tv, when he was BITTEN by a bug that looks very similar to this one. The differences: our beetle has smaller looking teeth things on the mouth, and the middle section between the head and elongated wing section do not have the thorny things like your does. It is still 2 inches long, and very slight stripes down the wings (yours are more pronounced.) Otherwise, everything else is the same. I wish I could post a picture here, as well as a pic of the bite, it has raised only slightly so I don't think the beetle is poisonous. He isn't having a reaction yet, thank goodness! P.s... We live in Georgia! Any ideas?

Spatula said...

My son was in our basement rec room this morning, watching tv, when he was BITTEN by a bug that looks very similar to this one. The differences: our beetle has smaller looking teeth things on the mouth, and the middle section between the head and elongated wing section do not have the thorny things like your does. It is still 2 inches long, and very slight stripes down the wings (yours are more pronounced.) Otherwise, everything else is the same. I wish I could post a picture here, as well as a pic of the bite, it has raised only slightly so I don't think the beetle is poisonous. He isn't having a reaction yet, thank goodness! P.s... We live in Georgia! Any ideas?

Spatula said...

I was wrong. It does have the thorns on it, and thanks to your blog I researched all over and we definitely have your same Orthosoma Brunneum here. Every thing I have read says they enjoy decaying woods and wet places, but this guy sank his teeth in my 8 year old's armpit, on the sofa. We are guessing he got inside when my husband left the downstairs door open while painting. Your pictures are wonderful, thanks for your post.

AYDIN ÖRSTAN said...

This has become a very popular post. That's probably mostly because of the title, which seems to be the 1st thing people think of when they encounter this insect. Thanks everyone for their comments. However, I'm afraid I can't answer specific questions, because I'm not an entomologist.

katlin said...

I live in an Dallas apartment complex. The other night had pizza delivered to the pool. I later took box inside. When I opened the box, he was munching on the pizza. Jumped on the floor, and immediately smashed it on the floor. I was freaked! Just now I picked up a pair of jeans, and found another. Didn't want smushed bug on carpet, so chased him out the door. Wow they are fast! Trying to get out of heat?

Anonymous said...

uggh. just found this on the side of my house, but it's more like 3inches long. We left the lights on out on the porch tonight and have a million moths and a few strange looking beetles not seen during the day!
Lisa in Stormville, NY

katlin said...

I found one more under my keypad.

Anonymous said...

We just found one out in our mulch near our front porch. Our dog actually heard it and got it out of the mulch! Thank you for your post! I was so scared it was a cockroach!!

Diane Sigler said...

My husband just took the dogs out and one of these ugly critters was flying around the light and hit the side of the garage. It landed and started hissing at the dogs. I'm glad I wasn't out there! We are in northern Cali, outside of Redding.

Britta said...

found one of these nasties on my front door when I came home this evening ... I live in central Massachusetts.

grosses me out!

Anonymous said...

Thanks for putting this photo online! I just spent an hour trying to ID this bug and your site is the only one that has it, out of at least 8 others!
Found it dead in the corner of the living room, here in Baltimore.

nohuiam said...

Took two really good pics of this kind of beetle just now. Please contact me if you'd like them.

stefidragonfly said...

perhaps look up stag beetle. he may have been pinched instead of bitten.

Anonymous said...

Just found the same bug, a little over 2 inches, dead in my kitchen sink in a bowl ow water. Freaked me out. This is the only website I could find for an accurate identifaction. Thank you.

Anonymous said...

we were in Northern Wisconsin this weekend... they attacked the screen tent we were in at night when we turned the lights on...
they are huge and evil looking...

Anonymous said...

I thought a bird was dive-bombing me in my bathroom! Covered with a plastic container, it's still alive more than 24 hours later. Now that I've identified it, I'll set it free here in the woods of Massachusetts. Thanks for your great photos.

Kelsey said...

Today I was walking in my kitchen and i stepped on one, and it clamped onto my foot and bit the sh** out of me. I had a large bubble around it, and the bubble is numb. Am i going to die?

AYDIN ÖRSTAN said...

Yes. Nobody is immortal.

Alicia p. said...

In Chelan WA at lake chelan state park and one flew towards our latern. Scared the crap out of everyone!

Tyler Pomeroy said...

Found this bug in the basement today 7/25/12 in Boise Idaho. Glad to know it's not a Roach.

Anonymous said...

Just founf one of these on my basement stairs. (Ontario, Canada) It was on it's back and couldn't get right side up again.

Anonymous said...

Last night my son & I was at a friend"s house BBQing & making store's. Having a good time. My son came up to us very calmly to tell us there was a bug a us. I looked & ask my son where? He said "not you mom, her". So my friend tried to brush it off. She turned her back left shoulder towards me to brush it off for her. When I saw that huge beetle on her, I screamed & ran lol. Scared the crap out me lol. Made her screamed & yelled to get it off of her. The other 2 girls screamed as well lol. I've never a huge bug living in Southwest Idaho. I've seen bigger cockroaches in Phoenix Az, but not that kind of beetles in Southwest Idaho.

Anonymous said...

Great pic I found one in my pool and was happy to identify it

John Egan said...

Thanks for the pic and ID. We've had 2 of these in the last week. Each was about 2"+ not counting the antennae. Seemed harmless. We live in the foothills of California between Sacramento and Reno at about 2600 feet in a forested area. Temperatures have hit the 100s, so I'm guessing they were trying to make it to the refrigerator for a beer.

Anonymous said...

Thanks for the great ID photo. I found one haplessly trying to escape from my kitchen sink this AM in New Paltz, NY. I looked all thru the NY State bug ID site and it wasn't there! But it sure IS here. I wish it were dead so I could add it to my bug collection, but I never collect live specimens, only dead ones I happen to find. So I shall put it out on a dead log and wish it Godspeed...
NY Gardener

Anonymous said...

this is an Elm root beetle. Derobrachus geminatus. also known as root borer, or prionid beetle. its a longhorn beetle. the adults have a short life, live mostly as grubs for a few years eating your tree roots, and harming the trees. the grubs are rather nasty looking in my opinion.

Anonymous said...

I live in eastern Ohio, and I caught 2 of these in our pool skimmer. They are over an inch long from nose to end of abdomen. Crazy big!

Anonymous said...

Just found one of these guys in my basement! I, like others on here thought it was a roach! What a relief!! Mountains of NC

Anonymous said...

I just found one that's 2 inches long right outside my window! It was huge-2 inches! Found it in Western Canada.

oogy83 said...

One almost flew into our House through an open window on our deck, whizzing past my head! Its about 3 inches lint and very aggressive, hiding, screeching and flying all over (and in the pot I caught it in. Thanks for the info, it scared the crap out of me! My husband thought it was a cockroach too, but its underside was slightly hairy. S. Oregon

Anonymous said...

I keep getting these. In my garage Colorado