Gibboryctes waldenfelsi ( Endrödi 1977 )

Alvarez, Héctor Jaime Gasca, da, Claudio Ruy Vasconcelos, Fonseca & Ratcliffe, Brett C., 2008, Synopsis of the Oryctini (Coleoptera: Scarabaeidae: Dynastinae) from the Brazilian Amazon, Insecta Mundi 2008 (61), pp. 1-62 : 16-18

Gibboryctes waldenfelsi ( Endrödi 1977)

( Fig. 21-25 )

Strategus waldenfelsi Endrödi 1977: 335

Gibboryctes porioni Dechambre 1981: 124 (synonym)

DESCRIPTION. Length: 22.6 mm, given as 26.0-30.0 in Endrödi (1985). Width: 14.6 mm. Color: Dark reddish brown.

Males. Head: Frons shiny, concave. Surface punctate and rugose, with a conical tubercle ( Fig. 22 ). Eye canthus with apex truncate to almost quadrangular. Clypeus with apex truncate, reflexed, surface shiny. Antenna with 10 segments, club subequal in length to segments 2-7. Mandibles broadly exposed, with 2 large, subequally rounded lobes. Pronotum: Surface smooth, with micropunctures. Prominence broad, bifurcate, forming a subtriangular, deep fovea. Projections rounded. Anterior horn long, recurved, apex strongly dilated and weakly bilobed. Base with marginal bead. Elytra: Surface with rows of punctate striae; punctures deep, ocellate. Humerus smooth. Lateral margins punctate. Pygidium: Surface strongly punctate, setigerous, convex in lateral view; punctures deep, ocellate; setae long, fine. Legs: Protibia quadridentate. Posterior tibia with apex crenulate. Posterior tarsus with apex of first tarsomere expanded. Venter: Prosternal process short, broad, apex rounded. Parameres: Long, slender, slightly contracted towards apex. Apex convex, setigerous medially ( Fig. 23-24 ).

Females. As males except in the following respects: Head: Frons with surface coarsely rugose. Tubercle long with apex rounded. Clypeus with apex broadly rounded. Pronotum: Horns absent, fovea not deep. Sides with surface punctate. Fovea and anterior angles rugose. Pygidium: In lateral view, surface weakly convex.

DIAGNOSIS. Gibboryctes waldenfelsi can be distinguished by the deep broad almost triangular fovea on the pronotum, the form of the pronotal horn that is slender and emarginate in the males, and by the bilobed mandibles.

DISTRIBUTION. Gibboryctes waldenfelsi is found from southern Panama to the eastern slopes of the Andes in central Peru, the Amazon region of Brazil, and the Guianas. Ratcliffe and Dechambre (1983) noted records for Manaus and Taracuá ( Fig. 31 ). It is rare in research collections.

LOCALITY RECORDS. ( Fig. 25 ) 1 specimen examined (1 male). A specimen was seen from the following collection : CZPB

AMAZONAS (1). Novo Airão ( Ramal do Olimpo ) .

TEMPORAL DISTRIBUTION. January (1).

NOMENCLATURAL REMARKS. Endrödi (1977) described this species in the genus Strategus . After examining the holotype, Ratcliffe and Dechambre (1983) concluded that is was a species of Gibboryctes , and they transferred it to that genus.

BIOLOGY. Gibboryctes waldenlfelsi is very rare in collections, and there is little biological information about its natural history. Adults are attracted to lights ( Ratcliffe 2003). In Brazilian Amazonia, this species is associated with semi-humid ombrophilous forests, and areas of seasonal whitewater inundation forest (várzea).

Figures

Figure 25. Distribution of Gibboryctes waldenfelsi in Brazilian Amazonia.

Figure 21-24. Gibboryctes waldenfelsi. 21) Habitus. 22) Male head and pronotum (scale line: 5 mm). 23) Parameres frontal view. 24) Parameres lateral view (scale line: 1 mm).

Figure 29-31. Heterogomphus eteocles. 29) Metatarsus. 30) Parameres frontal view. 31) Parameres lateral view (scale line: 2 mm).