1	Outer subhumeral elytral stria more or less complete, may be interrupted or slightly fragmented toward base	2
–	Outer subhumeral stria shorter, absent from basal half	3
2	5th dorsal elytral stria complete(Fig. 58D)	Operclipygus quinquestriatus sp. n.
–	5th dorsal elytral stria present only in apical half (Fig. 58E)	Operclipygus campbelli sp. n.
3	4th dorsal elytral stria arched mediad at base toward, sometimes reaching, elytral suture(Fig. 58A)	4
–	4th dorsal stria not arched mediad at base, more or less parallel to 3rd stria	5
4	Anterior and lateral submarginal pronotal striae continuous across front of pronotum(Fig. 59F); Central America	Operclipygus propinquus sp. n.
–	Anterior submarginal pronotal stria detached from lateral, briefly recurved posterad behind eyes; southeastern U.S.A., northern Mexico(Fig. 58A)	Operclipygus geometricus (Casey)
5	Lateral submarginal pronotal stria obsolete in basal half or more	6
–	Lateral submarginal pronotal stria reaching base, may be fine and close to margin, rarely interrupted at middle	9
6	Lateral submarginal pronotal stria meeting pronotal margin near midpoint(Fig. 59G), diverging strongly toward front, nearly meeting anterior submarginal stria, which is strongly arcuate, ends oblique, not recurved directly posterad; propygidium and pygidium lacking microsculpture	Operclipygus intersectus sp. n.
–	Lateral submarginal pronotal stria not meeting pronotal margin at midpoint, nor diverging so strongly from margin toward front, may be continuous with anterior submarginal; at least propygidium with conspicuous microsculpture	7
7	Body distinctly bicolored(Fig. 58F)	Operclipygus dybasi sp. n.
–	Body unicolored	8
8	Anterior and lateral submarginal pronotal striae continuous across front; males with narrow depression along anterior half of the lateral submarginal stria, this depression delimited posteriorly by a fine, parallel secondary stria which abruptly bends to margin at middle(Fig. 59B); Central America	Operclipygus impressicollis sp. n.
–	Anterior submarginal stria detached from lateral, ends recurved posterad(Fig. 59H); males and females both with weak, indistinct depression behind submarginal stria, not delimited by secondary stria; Venezuela	Operclipygus troglodytes sp. n.
9	Pronotum lacking coarse lateral punctures(Fig. 60A); marginal pygidial sulcus weak, fragmented apically, may be absent(Fig. 60B)	Operclipygus montanus sp. n.
–	Pronotum with conspicuous lateral punctures; pygidial stria varied	10
10	Anterior submarginal pronotal stria detached from lateral, forming an even arch across anterior one-third of pronotum(Fig. 56C)	Operclipygus arquus sp. n.
–	Anterior submarginal pronotal stria either continuous with lateral, or if detached, recurved perpendicularly posterad, not forming a smoothly curved arch	11
11	Marginal pronotal stria descending to hypomeron about one-fourth behind anterior pronotal corner, conspicuously disrupting margin(Fig. 56F); propygidium and pygidium with conspicuous microsculpture(Fig. 56B); frontal stria usually complete; northern Central America, southern Mexico	Operclipygus hamistrius (Schmidt)
–	Marginal pronotal stria not disrupting margin, rarely descending to hypomeron closer to anterior corner; other characters varied	12
12	Outer subhumeral stria absent; marginal mesoventral stria(Fig. 58C) complete along anterior margin; not displaced by mesometaventral stria; pygidium lacking microsculpture	Operclipygus rubidus (Hinton)
–	Outer subhumeral stria present in apical half of elytron; marginal mesoventral stria interrupted at middle; pygidium with microsculpture or not	13
13	Propygidium and entire pygidium with conspicuous microsculpture; anterior submarginal pronotal stria detached from lateral stria, ends recurved posterad (Fig. 59C); pronotum with conspicuous ground punctation, especially toward sides; head broad; labrum wide, emarginate(Fig. 4D)	Operclipygus nubosus sp. n.
–	Pygidium with microsculpture at most along basal margin, frequently entirely lacking; anterior and lateral submarginal pronotal striae continuous along anterior margin	14
14	Marginal pygidial sulcus well-impressed around apical half; lateral submarginal pronotal stria very close to margin, complete(Fig. 49A)	Operclipygus rufescens sp. n.
–	Marginal pygidial sulcus weak, fragmented near apex; lateral submarginal pronotal stria more distant from margin, may be interrupted at middle	15
15	Ground punctation of pronotum conspicuous(Fig. 59D); frontal stria complete; northern Central America	Operclipygus chiapensis sp. n.
–	Ground punctation of pronotum fine, sparse(Fig. 58G); frontal stria interrupted at sides; Ecuador	Operclipygus pichinchensis sp. n.