Key to species of Hybochaetodus

1. Pronotum with posterior margin sinuous or with a distinctive medial projection; pronotal posterior angles nearly right­angled................................................................ 2

1’. Pronotum with posterior margin rounded; pronotal posterior angles rounded (Fig. 8).. .......................................................................................................... H. obscurus Arrow

2. Elytron with four distinctive, smooth, continuous carinae (including sutural carina); carinae extended from elytral base to declivious apical area (Figs. 3–4)........................ ............................................................................... H. erugocarinatus Ocampo sp. nov.

2’. Elytron without distinctive, continuous, smooth carinae .............................................. 3

3. Elytral shape globose; elytral disc convex; all five elytral carinae distinctively interrupted (Figs. 1, 2) ............................................................ H. disruptus Ocampo sp. nov.

3’. Elytral shape elongate; elytral disc nearly flat; one lateral, discal carina; carina continuous, not interrupted (Fig. 7) ................................................................ H. flaco Ocampo