One of the prionid beetles. Due to the very wide thorax and somewhat rounded body, a tentative ID would be Broad-necked Root Borer - Prionus laticollis. Certainly a prionus, many to choose from, bugguide.net lists over 30 different species of subfamily Prioninae beetles.

In general, to call it a root-borer beetle would be accurate.

Note the partially missing extremities (one or both antennae, one rear foot). This can happen when more than one of these beetles encounter each other, their mandibles are very strong.

Thank you very much :)