I key it out to O. nitens with this key: http://cjai.biologicalsurvey.ca/bnkmm_12/keys/genus/c1.html
Any confirmation would be appreciated. I can't find a record of it in Webster's 2016 NB checklist or in Bousquet's Canadian checklist.
First image you can measure on your screen - elytra at middle shorter than pronotum
Second shot - lateral setae restricted to anterior half of temple
Third shot is maxillary palp - elongate and rectangular
Nasonworth - May 2, 2018
Found burrowing down into sphagnum on edge of woods.
Nice! Following this discussion and would love to hear what the conclusion is, but I cannot help with ID.
I've gone through the key 3 times now, and compared to images on BugGuide.
I was so sure of the ID that I posted them to BugGuide. Then I found out it hadn't been recorded here (or in Canada?) so I panicked and removed my BugGuide pics. I'd be more sure of myself if it had already been recorded here.
I sent an email to Reggie Webster, and will repost to BugGuide at a different level.
Hopefully Boris or Reggie come through with a confirmation.
It is known from Canada, and parts of Maine - https://bdj.pensoft.net/articles.php?id=11012 .
Looking at your shots and the key - seems to be a match ?
Thanks x 2 Danny.
I must have an earlier copy of Bousquet's checklist. I also should have checked BugGuide for distribution as they have a record from Ontario. Fingers still crossed for a first for N.B. though.
Being told by Reggie that it is Tasgius melanarius (most likely) or T. ater.
I can't make it fit to either based on what info I find in the key.
I'll add more pictures.
Boris Büche from BugGuide/iNat says O. nitens.
When I looked at the key earlier, I thought it looked more like T. winkleri than T. melanarius based on the pronotal shape. The solid red colour of the antennal base in your latest pic would suggest that as well. But that means the pronotal length vs elytral length as being diagnostic, is incorrect, or your shot distorts the actual lengths. In your photo it clearly appears to fit O. nitens; harder to discern the palp shape from your photo. Have the drink and go back at it :-)
I have several T. melanarius, but cannot see the dentition because the mandibles are tightly closed. These shots show the mandibles are quite different. Definitely a stronger case for O. nitens.