Synopsis of the cyclocephaline scarab beetles (Coleoptera, Scarabaeidae, Dynastinae) Author Moore, Matthew R. Author Cave, Ronald D. Author Branham, Marc A. text ZooKeys 2018 745 1 99 http://dx.doi.org/10.3897/zookeys.745.23683 journal article http://dx.doi.org/10.3897/zookeys.745.23683 1313-2970-745-1 16F1AE595650485F9D8C6149E962D461 Acrobolbia Ohaus, 1912 Type species. Acrobolbia macrophylla Ohaus, 1912, by monotypy. Valid taxa. One species. The northern South American genus Acrobolbia is known from Peru, Ecuador, and possibly Venezuela ( Ohaus 1912 , Machatschke 1972 , Jameson et al. 2002 ) (Fig. 51). Acrobolbia has a complicated classification history. Ohaus (1912) described A. macrophylla based upon a single male specimen collected in Peru. Ohaus (1912) compared Acrobolbia to Cyclocephala , but he ultimately classified the genus in the subtribe Areodina ( Rutelinae : Rutelini ). Ohaus (1918) later transferred the genus into its own subtribe, Acrobolbiina , within Rutelini . Acrobolbia triangularis was the second species to be described into the genus, but this species was later treated as a synonym and a "variant" of A. macrophylla ( Benderitter 1922 , Ohaus 1934a , b ). Figure 51. Country-level distribution of Acrobolbia macrophylla in South America. Numbers indicate taxa per country. The presence of A. macrophylla in Venezuela is based upon a single specimen without further label details. Based on the elongated antennal club of the male in Acrobolbia , the genus was transferred into the ruteline subtribe Oryctomorphina ( Dechambre and Ponchel 1999 ). Most recently, Acrobolbia was reviewed and transferred into Cyclocephalini by Jameson et al. (2002) . Acrobolbia is hypothesized to be related to Ancognatha based upon characters of the clypeus, mentum, pronotum, prosternal process, protarsus, and mandibles ( Jameson 1998 , Jameson et al. 2002 ). Specimens of Acrobolbia are rare in collections, and almost nothing is known of their biology ( Jameson et al. 2002 ). Acrobolbia macrophylla adults are attracted to lights at night, though specimens do not land or rest at light traps ( Jameson et al. 2002 ). Specimens have been collected from 400-1,200 m in elevation ( Jameson et al. 2002 ). The immature stages are undescribed and unknown. Acrobolbia species can be recognized by the following combination of characters: 1) dorsal coloration varying from all black with variable reddish brown margins of the elytra and elytral suture, or with the elytra partially testaceous; 2) body not anteroposteriorly compressed or dorsoventrally flattened; 3) clypeal apex acuminate in dorsal view; 4) frontoclypeal suture distinct, but incomplete medially; 5) mandibles long, sickle-shaped, with pointed apex; 6) mandibular molar area with rows of circular micropunctures; 7) apical margin of mentum weakly emarginate to nearly straight; 8) galea of maxilla reduced to small, rectangular mound in dorsal view; 9) galea on inner surface with teeth greatly reduced to peg-like projections at the middle and apex; 10) galea on inner surface lacking teeth at base; 11) males with antennal club (segments 8-10) elongated, nearly twice as long as antennomeres 1-7; 12) pronotum with broadly incomplete beaded basal margin; 13) males and females with 3 protibial teeth, basal tooth reduced, removed from the apical 2 teeth, and oriented laterally; 14) protibial spur straight to weakly deflexed; 15) males with inner protarsal claw enlarged and narrowly cleft at apex; 16) mesocoxae touching, nearly contiguous; 17) meso- and metatibiae with distal, divided carinae; 18) metacoxae with lateral edge perpendicular to ventral surface; 19) anterior edge of hindwing distal to apical hinge lacking setae and with produced, membranous border; 20) vein RA with 2 rows of pegs extending distally nearly to margin of apical hinge.