...I can't see how it could be anything other than Archodontes melanopus serrulatus. It's holding the mandibles more horizontally than I would expect for this species but otherwise has the general appearance of that species, with the pronotal shape matching subspecies serrulatus (known from the southern U.S. west of the Mississippi River west to Arizona). The short 3rd antennomere excludes Strongylaspis (which is restricted in the U.S. to southern Florida), and the lack of carinae on top of the mandibles and obtuse antennal tubercles exclude the widespread Mallodon dasystomus, Nothopleurus (west Texas to Arizona and southern California), Neomallodon (Arizona), and Stenodontes (southern Florida). Utah is an interesting distributional record - to my knowledge none of the Macrotomini have been recorded from the state. I don't suppose you have the specimen?

a detail from the only other shot I have of this individual, although I don't imagine it gives you any new information.

Would these images best be placed at species, genus, or subfamily level?