1	Left mandible with strong tooth (Fig. 62E); labrum outwardly arcuate; ends of anterior submarginal pronotal stria recurved straight back about one-third pronotal length (Fig. 62B)	Operclipygus plicicollis (Schmidt)
–	Left mandible with small or no tooth; labrum truncate to emarginate; ends of anterior submarginal pronotal stria shorter or recurved obliquely posterolaterad, or both	2
2	Anterior submarginal pronotal stria with ends curving posterolaterad from pronotal margin (Fig. 62D); left mandible with small basal tooth (Fig. 62F); labrum very short, transverse, not emarginate apically	Operclipygus cephalicus sp. n.
–	Anterior submarginal pronotal stria with ends bent straight posterad, very short, extending less than one-sixth pronotal length; left mandible completely untoothed (Fig. 62G); labrum short but distinctly emarginate apically (Fig. 62G)	Operclipygus longidens sp. n.