1	Head with small horn or tubercle mesad of each eye (Figs 35, 36). Costa Rica to Ecuador	Pucaya Ohaus, 1910
–	Head without horn or tubercle mesad of each eye (Ancognathacastanea Erichson has frons with low, median knob or elevated, transverse tubercle)	2
2	Apex of labrum chitinized (thickened). Labrum extends past the apex of the clypeus in dorsal view (Fig. 8). Asia	Peltonotus Burmeister, 1847
–	Apex of labrum not conspicuously thickened. Labrum does not extend past the apex of the clypeus in dorsal view	3
3	Mandibles broad, nearly as wide as long (Fig. 9). West Africa	Ruteloryctes Arrow, 1908
–	Mandibles narrow, distinctly longer than wide	4
4	Propygidium mostly covered by elytra, with long, dense setae that protrude from beneath elytral apices; propygidium often elongated, so that pygidium appears moderately to extremely shortened. Body noticeably tapered at both ends. Protarsus in males with tarsomeres 4–5 and claw enlarged. South America, West Indies	Chalepides Casey, 1915
–	Propygidium lacking long, dense setae; length of propygidium normal. Body not noticeably tapering at both ends. Protarsus in males with tarsomeres and claw enlarged or not	5
5	Body form strongly flattened, relatively large (24–44 mm). Color black. Clypeus with apex narrowly to broadly parabolic (Figs 10, 11)	6
–	Body form not flattened, size smaller (6–29 mm, and some larger individuals of Ancognatha). Color variable, including patterns. Clypeus with apex variable, parabolic or not	7
6	Eyes large, interocular width equals 2.0 or less transverse eye diameters. Males with protibia slender, strongly curved, with distinct tooth on inner margin near base (Fig. 12); anterior trochanter with large, anteriorly projecting tooth. Northern South America	Harposceles Burmeister, 1847
–	Eyes smaller, interocular width usually 3.0 or more transverse eye diameters. Males with protibia “normal”, not curved strongly, lacking tooth on inside near base; anterior trochanter lacking anteriorly projecting tooth. South America	Surutu Martínez, 1955
7	Clypeus with sides slightly wider than base before abruptly narrowing to acuminate apex (Fig. 13). Males with antennal club almost twice as long as antennomeres 1–7 (Fig. 13). Meso- and metatibiae at apex with spinose process on external edge. Northwestern South America	Acrobolbia Ohaus, 1912
–	Clypeus with sides tapering from base to apex (rounded, parabolic, subtriangular, or sharply acuminate), or with sides divergent from base to apex, but with apex never abruptly acuminate (Figs 14–24). Males with antennal club slightly longer than, subequal to, or shorter than antennomeres 2–7. Meso- and metatibiae at apex without spinose process on external edge	8
8	Lateral margins of clypeus near base raised into a subacute crest, evident in posterodorsal view (Fig. 25). Clypeus thickened along the frontoclypeal suture. Frontoclypeal disc concave (Fig. 25). Specimens with double tubercles or faint declivity near anterior margin of pronotum. Costa Rica to Peru and Brazil	Parapucaya Prell, 1934
–	Lateral margins of clypeus near base flat or faintly raised into a round crest, evident in posterodorsal view (Fig. 26). Clypeus flat or weakly thickened along the frontoclypeal suture. Frontoclypeal disc convex or concave (Fig. 26). Specimens without double tubercles or faint declivity near anterior margin of pronotum	9
9	Clypeus trapezoidal or subtrapezoidal, with marginal or apical bead (Fig. 27–28)	10
–	Clypeus with apex rounded, truncate, subquadrate, or emarginate, simple, with or without marginal bead (Figs 14–24)	11
10	Frontoclypeal suture distinct, usually broadly depressed just before suture. Males with protarsomeres simple, not enlarged. Pronotum with anterior margin normally arcuate, not produced forward at middle (Fig. 27). Meso- and metafemora and meso- and metatibiae strongly flattened. Central and South America	Stenocrates Burmeister, 1847
–	Frontoclypeal suture a finely impressed line but not with deep and broad impression before it. Males with anterior claw and usually protarsomeres 4–5 enlarged. Pronotum on anterior margin produced anteriorly at middle (Fig. 28). Meso- and metafemora and meso- and metatibiae not strongly flattened. North, Central, and South America, West Indies	Dyscinetus Harold, 1869
11	Body form short, suboval, stout; elytra nearly as wide as long. Clypeus subquadrate, about twice as wide as long, apex broad, subtruncate, broadly reflexed (Fig. 14). Size 14–16 mm. Brazil, French Guiana	Arriguttia Martínez, 1960
–	Body form usually elongate, not short or suboval or stout; if so, then length less than 14 mm (usually 9–12 mm). Clypeus with apex rounded, broadly parabolic, subquadrate, or emarginate (Figs 15–24)	12
12	Clypeus with sides usually divergent (sometimes only slightly) from base to apex, apex broadly rounded (Fig. 16). Maxilla lacking well-developed teeth (when teeth present they are minute and obscured by setae), apex penicillate (setae usually long and dense). Mexico to Argentina	Aspidolea Bates, 1888
–	Clypeus with sides parallel or convergent from base to apex (never divergent), apex rounded, subtruncate, or emarginate. Maxilla armed with distinct teeth, apex rarely penicillate (a few species of Cyclocephala)	13
13	Elytra distinctly, irregularly punctate, punctures not in regular rows; surface with or without weak metallic sheen. Clypeus with apex nearly semicircular, margin beneath apex distinctly thickened (Fig. 15). Venezuela, Peru, Bolivia, Brazil	Augoderia Burmeister, 1847
–	Elytra smooth or distinctly punctate, some punctures in regular rows; surface never with metallic sheen. Clypeus with apex variable, semicircular or not, margin beneath apex not distinctly thickened	14
14	Clypeus subquadrate, sides weakly converging to broad apex, apex truncate or emarginate (Figs 17, 18). Interocular width 6.0 or more transverse eye diameters (Figs 17, 18). Males protarsus and claw simple, not enlarged. Central and South America	Erioscelis Burmeister, 1847
–	Clypeus not subquadrate, instead with sides converging from base to rounded, parabolic, subtriangular, or emarginate apex (Figs 19–24). Interocular width 5.0 or less transverse eye diameters (Figs 19–24). Males protarsus enlarged, with bifurcate median claw	15
15	Mentum with apex distinctly (often deeply) emarginate, surface at center furrowed in apical third (Fig. 29). Mandible elongated, apex extended to or beyond clypeal apex. Frontoclypeal suture obsolete medially. Length usually more than 18 mm, rarely as small as 15 mm. North, Central, and South America	Ancognatha Erichson, 1847
–	Mentum with apex truncate or weakly emarginate (Fig. 30). Mandibles not elongated. Frontoclypeal suture more or less complete. Length variable, 6–35 mm. Canada to Argentina, West Indies (one species introduced to Australia, one species introduced to Hawaii)	Cyclocephala Latreille, 1829