Found under a lighted wall. I believe only males have horns. (Corrections welcome, of course.) Captured and posed. See guide page for identification references.
Bolboceras liebecki, since that is the species mentioned for the Piedmont of South Carolina in Harpootlian's
Scarab Beetles of South Carolina (1). See comments for confirmation--thanks Phil!
This image is currently used on the title page for family
Bolboceratidae at the
Tree of Life.