Harposceles Burmeister, 1847

Moore, Matthew R., Cave, Ronald D. & Branham, Marc A., 2018, Synopsis of the cyclocephaline scarab beetles (Coleoptera, Scarabaeidae, Dynastinae), ZooKeys 745, pp. 1-99 : 56

Harposceles Burmeister, 1847

Type species.

Harposceles paradoxus Burmeister, 1847: 35, by monotypy.

Valid taxa.

One species.

The monotypic genus Harposceles was erected for the species H. paradoxus . This striking, relatively large cyclocephaline occurs in lowland forests in Brazil, Ecuador, French Guiana, Peru, Suriname, and possibly Colombia ( Burmeister 1847, Harold 1869b, Arrow 1937b, Blackwelder 1944, Endrődi 1966, 1985a, Endrődi and Dechambre 1976, Lachaume 1992, Couturier and Kahn 1992, Andreazze 2001, Andreazze and da Silva Motta 2002, Touroult et al. 2010, Ponchel 2011, Saltin and Ratcliffe 2012, Ratcliffe et al. 2015) (Fig. 60). Males display dramatic, and unique, characters of the protibia. Harposceles paradoxus males have elongated, arcuate protibia with the protibial spurs fused to the base of the tibia. Females are much less common than male specimens in collections, and males are readily attracted to lights at night, especially between midnight and 4 am ( Andreazze 2001, Andreazze and da Silva Motta 2002, Touroult et al. 2010, Saltin and Ratcliffe 2012). The immature stages of H. paradoxus are associated with the palms Astrocaryum chonta Mart. and A. carnosum F. Kahn & B. Millán ( Arecaceae ) ( Couturier and Kahn 1992). The larvae and pupae were found in the organic litter accumulated between leaf sheaths of A. carnosum ( Couturier and Kahn 1992). The immature stages are undescribed.

Harposceles species can be recognized by the following combination of characters: 1) dorsal coloration dark piceous to black; 2) body dorsoventrally flattened; 3) clypeus rounded in dorsal view; 4) frontoclypeal suture incomplete medially; 5) apical margin of mentum truncate; 6) anterolateral margin of mandible lacking tooth; 7) mandibular molar area with surface lacking circular pits, with large, disorganized, canal-like invaginations; 8) galea of maxilla dorsoventrally flattened; 9) galea on inner surface at base with large, flattened, blade-like, tooth (less produced than in Surutu species); 10) galea on inner surface with 7 teeth in 2-1-1-1-2 arrangement from base to apex; 11) apical and basal beaded margins of pronotum complete at middle; 12) anterior membrane of the pronotum interrupted before lateral pronotal margins; 13) males with protrochanter with ventrally produced tooth; 14) protibia with 3 teeth in both sexes; 15) males with protibia elongated and arcuate; 16) protibial spur straight to weakly reflexed; 17) males with protibial spur fused to protibia, not articulated at its base; 18) males with inner protarsal claw thickened and not cleft at apex; 19) mesocoxae not widely separated, nearly touching; 20) metacoxae with lateral edge perpendicular to ventral surface; 21) apices of the meso- and metatibiae with a corbel; 22) anterior edge of hindwing distal to apical hinge lacking membranous border; 23) anterior edge of hindwing distal to apical hinge with decumbent setae surrounding vein and originating away from apical hinge; 24) vein RA with single row of pegs proximal to apical hinge.

The relationship of Harposceles to other cyclocephalines has not been elaborated upon in the literature. However, H. paradoxus shares some characters with Surutu that may be indicative of a close relationship between the two genera. The rounded shape of the clypeal apex in H. paradoxus is like the clypeal form in S. dytiscoides . The single row of RA pegs in H. paradoxus is shared between Ancognatha and Surutu , though Ancognatha species lack setae on the anterior edge of the hindwing distal to the apical hinge. The decumbent setae of the hindwing leading edge (distal to apical hinge) found in H. paradoxus is also found in Surutu species and the " Cyclocephala cribrata species group" (which included species previously placed in Mononidia and Surutoides ) ( Dechambre 1997). These groups also all share corbeled meso- and metatibial apices and entirely black coloration. Harposceles paradoxus shares other interesting characters with Surutu species. These shared characters include: 1) body strongly dorsoventrally flattened; 2) dorsoventrally flattened maxillary galea; 3) a seven-toothed maxillary galea in a 2-1-1-1-2 arrangement from the base to apex; 4) an incomplete frontoclypeal suture; and 5) the apical pronotal membrane interrupted before the lateral margins of the pronotum. The large basal tooth of the maxillary galea is much smaller and less produced in H. paradoxus than in Surutu species. Several male characters of H. paradoxus are autapomorphic in Cyclocephalini : 1) the protibial spur fusion to the protibial; 2) the arcuate, elongated protibia (seen also in some Dynastini ); and 3) the ventrally produced protrochanter teeth.