1     Outer margin of connexiva alternating pale and dark; anterolateral margins of pronotum distinctly depressed or angled in middle behind anterior row of teeth; basal abdominal spine robust, protruding between metacoxae; posterior angles of pronotum lacking tooth or spine (S. Texas to northern South America)

-      Outer margin of connexiva entirely pale; anterolateral margins of pronotum straight to slightly convex, no depression or angle behind anterior row of teeth; basal abdominal spine short, not protruding between metacoxae; each posterior angle of pronotum with a small tooth or spine (Montana, Colorado, Arizona, New Mexico, Mexico)