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Stag beetle 3rd Instar larva - male

Stag beetle 3rd Instar larva - Male
Madison, Dane County, Wisconsin, USA
May 29, 2023
Lucanus placidus or L. capreolus? Stag beetle larvae found in or beneath rotting hardwood (oak/hickory), trying to determine species. Segregated by gender, these are the males.

Location is a garden plot that was originally stripped of topsoil; remediation began in 2020 when logs with some decay were imported from bottom layer of a woodpile, along with some fresh logs. Logs were buried partially into clay, then covered in decayed wood chips, straw, and wood-rot from an old-growth wood. May 12, 2023, rearranging the garden rows revealed approximately 40 of these grubs beneath or inside the hardwood logs that had acquired white-rot fungi such as Trametes ssp.

Images of this individual: tag all
Stag beetle 3rd Instar larva - male Stag beetle 3rd Instar larva - male Stag beetle 3rd Instar larva - male

Moved from Lucanus.

Moved from ID Request.

Lucanus species differentiation?
Any way to determine which species of Lucanus these are?

I put the photos into "ID Request" rather than landing them in Genus Lucanus because I was hoping someone has the expertise to determine the species prior to maturity. Is it possible to look at the development of the pincers at this stage, or some other feature, to make that determination?

Not sure if it's possible with the larvae
If someone knows Lucanus really well they'll look under the genus. It could be possible to ID to species based on setal patterns, but I'm not sure.

Then back to ID, please?
Could we put this back into ID request, then, to see if there is someone who knows Lucanus really well? No offense, but that's why I started the original ID Request clearly stating that I wanted to determine which *species* of Lucanus I had.

It's up to you
Only you and Editors can move your photos. In general, specialists on X taxa are going to check within their area of specialty more often than in the ID Request tab, where everything is jumbled together. Some specialists certainly do check ID Request, but you tend to get better results once pics have been moved out of there. Which is why I moved them.

That said, I'm not sure who the lucanid experts are who are on BG. I see that MJ Paulsen is around, so if she sees it she may be able to weigh in. It may be better placed at Lucanidae if that's the case since that seems to be where most unIDed lucanids were moved from. Species-level ID may not be possible without rearing the larvae out, but I haven't dug too deeply into the literature to find out.

Thanks, Tyler! This is my fir
Thanks, Tyler! This is my first ID request post, and I appreciate you taking the time to explain how this works.

Not a problem! And welcome to BugGuide!
It can be a bit confusing sometimes, so the other editors and myself are happy to help where we can!

Did you want your photos moved up to Lucanidae for the next time MJ comes by to look at things?

That would be great, yes! Int
That would be great, yes! Into Lucanidae, please.

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