This is Amblycheila halferti which is not in the options
Ironclad Beetle (Zopherus xestus)
United States: Texas: Brewster Co.
Big Bend National Park; Chisos Basin
24-28.Aug.2016
J.C. Abbott #2860
Atascosa county
Found on shoreline of southern kleberg county
15mm long, Nocturnal, found on open rocky slope.