For always being such a good behind the scenes ID "Wizard of Oz" for us all on BugGuide :-) Very much appreciate your obtaining det. from P. E. Skelley himself! And, of course, my gratitude goes to the good Dr. S. as well. (Not only for his gracious BugGuide ID's ... but also for the formidable labor and problem-solving behind all the systematics he does :-)

Also...regarding a question in my (long) response to Blaine's previous move/comment below...I guess I now know "what the (D.) stands for": (Dellacaseillus? :-) I don't know how I missed that earlier, should have been visible at top of the web page when I started writing my response to Blaine (you know, late this morning = about a few millenia ago:-). Even if I weren't a certifiable slow-poke, I still wouldn't be able to keep up with you guys!

but the shape of the clypeus and teeth did not look right compared to that in Skelley's monograph.

But I gotta say...I'm very happy to have access to the Generic Guide to New World Scarab Beetles. It's a fantastic resource. Maybe try to see how this guy comes out there...after I get some lunch! :-)

Thanks again, Blaine.

I forgot to mention that this beetle went to subgenus Didactylia in the key for Aphodiinae on pg 400 in "old" (1968) Arnett(1). Is that what the "(D.)" stands for in A. (D.) fucosus, etc. ?

Here are the couplet numbers & choices I took:

1) Mandibles concealed beneath clypeus;
2) Thorax without transverse swellings; tarsal segments not triangularly expanded; apical spur of hind tibia acute;
3) Middle and hind tibiae with tranverse carinae (Tribe Aphodiini);
5) Hind and middle tibiae expanded from base to apex; anterior tibiae of male slender, two-toothed, of female three-toothed; middle sternites connate (subgenus Didactylia)

However, upon receiving your comment and reviewing my steps in the overall keying process, I discovered (to my dismay) two problems:
A) I neglected the character in blue in couplet 5 (after believing I'd verified the others)...perhaps this is no biggie/non-fatal; but...
B) Big Error! It seems I experienced a "couplet derailment" in the key to subfamilies of Scarabaeidae at the end of couplet 3 (pg. 398)...misreading the small print #'s for the subsequent lead (8 -> 5!! :-). If I try to go through that key again (not so unambiguous for me anymore :-) I end up at subfamily... Melolonthinae! May Beetles & June Bugs? Oops...something went wrong, they have "Dorsal surface often conspicuously setose or scaled" according to Generic Guide to New World Scarab Beetles.

Thing is, I think subfamily Aphodiinae is probably right, and I can't figure out if I made a mistake, or there's an error in the Arnett(1) key at couplet 3 on pg 398. (I know, that's a lot of hubris for a bumbling amateur like me to muster :-)

And I know this comment is getting awful long! But if you (or anyone else) has had the fortitude to read this far, and also has access to the "old" Arnett"(1), I'd be much relieved if you could check out couplet #3 on pag 398 and set me straight in regards to the above remarks!

PS:
1) I wonder what the names of the various relevant taxa are in Gordon & Skelley(2)?;
2) Maybe I'll try to key this using this online Generic Guide to New World Scarab Beetles. (Looks great! Didn't know about it until searching about the web, after reading your comment. Ugh! :-)