From a quick read, it's common, but we don't have any IDed here. Typical of a lot of common species, there don't appear to be a lot of photos around. Here's one:
http://www.biosurvey.ou.edu/okwild/misc/flowlong.html

That ID does look good but would hate to throw that label on it without any other peer review.

Agreed. Hope someone heavy weighs in.

It really looks like the other photo but I learned from prior misidentifications, that one little thing may be dignostic and I usually overlook it! :(

...Typocerus sinuatus because it lacks a dark transverse band across the base of the elytra (I think the photo in the 1st comment is also misID'd). Typocerus octonotatus is similar to T. sinuatus (the two are often confused in collections), but it lacks the basal band. It is also a common species in Illinois, whereas T. sinuatus is more of a southern species.

Looks like a pretty good guess. Maybe someone else will confirm your guess.

Apparently, that confirming someone wouldn't be Jim McClarin

BTW, is that the same flower?

...I think it is also Typocerus octonotatus.

I noted your comments under the other photo "ID can be confirmed by noting the presence (sinuatus) or absence (octonotatus) of a discrete sensory pore on the 6th antennal segment.". If I was to enlarge the antennae would that help make a more concrete ID? Now I know you mentioned discrete so this may be a super tiny pore.

...I mean 'separate and distinct' - however, the pores likely cannot be distinguished without a scope unless the light/antennal view are just right. Nevertheless, I am ~95% confident that this is T. octonotatus.