Omolabus

Key to north and central American Omolabus View in CoL species

1 Pronotum with irregular coarse punctures throughout, interspaces rugosely strigate; maleswithpaireddenticlesonheadandantero­venterofpronotum(subgenus Thyreolabus ) ....................................................................................................... O. spinipectus n. sp.

­ Pronotal punctures small, shallow; interspaces smooth, shiny; males without head den­ ticles or antero­ventral pronotal denticles .................................................................... 2

2 Eyes protuberant, sometimes only weakly so ............ (subgenus Omolabus View in CoL ) …......… 3

­ Eyes not protuberant, more or less flush with the surface of the head (figs. 69, 71, 73 & 75) ............................................................................................................................ 113

3 Eyes strongly protuberant (Figs. 30, 32, 42, & 44) ...................................................... 4

­ Eyes moderately to weakly protuberant (Figs. 46, 48, 50 & 52) ................................. 6

4 Elytra with dorsal posthumeral hump­like protuberances............. O. quadratus (Sharp) View in CoL

­ Elytra without dorsal posthumeral hump­like protuberances .................................... 5

5 Humeri simple, rounded, moderately protuberant .................. O. laesicollis (Gyllenhal) View in CoL

­ Humeri obliquely angled, denticulate; denticle prominent, bluntly tipped.............................................................................................................................. O. ligulatus (Sharp) View in CoL

6 Humeri obliquely angled, denticulate; denticle small, acute .... O. angulipennis (Sharp) View in CoL

­ Humeri simple, protuberant, rounded or obliquely angled ......................................... 7

7 Body entirely black; pronotum bifoveate, foveae sometimes only weakly impressed ...................................................................................................... O. corvinus (Gyllenhal) View in CoL

­ Body not entirely black; pronotum with or without foveae ........................................ 8

8 Body black with large reddish humeral maculae; frons concave with weak median carina ................................................................................................... O. heterocerus (Sharp) View in CoL

­ Body not black with reddish humeral maculae ........................................................... 9

9 Pronotum bifoveate..................................................................... O. longiclava (Sharp)

­ Pronotum smooth, without foveae ............................................................................. 10

10 Body pale reddish­brown; female with pair of setose patches on sternites 1–3; male with pair ofsmall postlabial bump­like projections ....................... O. fasciventris n. sp.

­ Body dark reddish­brown throughout; female without setose patches on sternites 1–3; male with pair of acute postlabial denticles...................................... O. sedatus (Sharp) View in CoL

11 Elytra with dorsal posthumeral hump­like protuberance ........................................... 12

­ Elytra without dorsal posthumeral hump­like protuberance ..................................... 13

12 Body black throughout, legs reddish­black; frons bisulcate; sulci extending on dorsal rostral base to antennal insertions .................................................. O. callosus (Sharp) View in CoL

­ Body reddish­brown throughout; frons with single median shallow channel confined to upper frons and lower vertex...................................................... O. megalomus n. sp.

13 Vertex and frons with wide shallow median channel; rostrum densely punctured beyond antennal insertions............................................................ O. conicollis (Sharp) View in CoL

­ Vertex weakly convex; frons bisulcate, weakly convex between sulci; rostrum sparsely punctured beyond antennal insertions.......................................... O. veracruensis n. sp.