Brown Prionid

what is it
I was just looking thru your site to try and identify this beetle I found tonight. It looks like the California long horn beetle. But I am in NH on vacation. Should I not release this insect. Is it not native to this area. I am sending the picture I took, but not very good since the beetle is in a vile for safe keeping until I hear that it is safe to release it.

We must confess that we were sure you had one of the Long-Horned Borer Beetles, but we were unsure of the genus and species. We asked Eric Eaton to try to clarify some identification points for us, which he did. However, in identifying your beetle, we now have an entirely new genus to consider. Here is Eric’s response: “This appears to be a female Orthosoma brunneum, the Brown Prionid. Just what you needed, eh, another critter to get confused by:-) Ergates are large, western mountains mostly, with FINE teeth on the edge thorax. Derobrachus are HUGE, almost exclusively southwestern (though range throughout the souther tier of states I am told). Prionus usually tend to be very squat, males with very thick antennae (almost comb-like or dentate in some species). An overall more robust critter than the others. Orthosoma is the most slender of all, and always a bright brown in color. Hope that helps, but getting Doug Yanega’s book on northeast longhorns would be your best bet (less than $20). Eric “

12 thoughts on “Brown Prionid”

  1. Ah! That is definitely him. I was looking at Hardwood Root borers and Pine Sawyers, which were all similar, but none looked 100% like the one I’d found. This one certainly is!

    Not to worry about the state of the prionid, I released him into the remains of a fallen tree an hour or so after sending this in and taking measurements. He’s safe and sound. It’s good to know he’s a native species, so I’m glad I saved him from my mother’s angry boot that night.

    Thank you! 🙂

  2. Just had one fly up to our porch!! (Southwestern Wisconsin) I’ve never seen one before. SO BIG!!
    I caught it in a glass and let it go about 3 blocks away 🙂

  3. Awoke at 530 am to this guy and when I got close he chirped and flew off. I have a child here so I spent 2 hours looking for him to no avail. I fell back asleep and bam just woke at 830 to him flying around my room. Finally found what he was in here thanks. Mansfield, Ohio it’s been in the 90’s here.

    Why is there barely any info on them out there??

  4. There are here in Idaho too. Biggest beetle I know of around here.

    I just got done picking one up, but buy the shell, they look like they have some fierce mandibles!

  5. Thank you.

    The beetle I saw last night looked just like the one in the photo above, and was 2in or more long not including the antennae.

  6. We live just outside of Philadelphia. Sitting in my office doing some work and my cat is going crazy near the desk shelves. I finally look and here’s one of these beetles! Now that I can identify it. Buzzing around. Captured it in a napkin and let it go outside. How did it even get in the house? Would it have been harmful to me or my cat?

  7. i have a tarp on the underside of my top deck for rain protection. while i was out feeding the feral cats i saw this giant brown bug on it but it was dark out..first thing when i got a flashlight and my glasses for better view i thought it was a palmetto bug since living in fla many years ago you never forget those things lol…anyway the face/head area wasnt the same and the antenna looked different but i just couldnt get a close look because i was afraid it would drop on me lol…thought id do a search of beetles in ct and this one came up right away and i believe it is what it is…i noted the head area was not the same as a palmetto before i came in to look online and when i saw a photo of this one i knew it was it…im in waterbury ct..and i also just learned that palmettos are not beetles..and why is it that i feel better knowing this is not a palmetto bug and just a giant beetle add a photo but i also have raccoon babies hanging around and when they hear the screen door they come running up looking for cat food. 🙂 thanks for posting everyone..its very helpful for someone like me who likes to research things i dont know 🙂

  8. I found one in my house last night (Stockbridge VT). It was laying on its back, kicking its legs trying to get back up. My first impressions is that it was a huge cockroach. Until I got up close and witnessed those scary/nasty looking pinchers as a mouth. I assume he was attracted to the light and squeezed into my house through the sides of a window unit air-conditioner. My wife would have had a heart attack if she found it. Will be sealing those open areas asap!


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