Dichotomius (Dichotomius) diabolicus ( Harold, 1875 )

8. Dichotomius (Dichotomius) diabolicus ( Harold, 1875) View in CoL species group

Diagnosis: The species of the D. diabolicus species group is recognized by the following combination of characters: (1) Medium-sized individuals with opaque appearance (15.5–20.4 mm). (2) Head oval as long as it is wide ( Fig. 16 View Figure 16 a-c). (3) Clypeus margined with two inconspicous clypeal teeth and with strong and transverse wrinkles ( Fig. 16 View Figure 16 a-c). (4) Ventral clypeal process with triangular appereance with obtuse tip ( Fig. 16d View Figure 16 ). (5) Males with cephalic process on clypeal area from lamellate to conical ( Fig. 16a, b View Figure 16 ) and females with conical to carinate process on fronto-clypeal area ( Fig. 16c View Figure 16 ). (6) Protibial spur not angled or slightly angled near the apex ( Fig. 16e View Figure 16 ). (7) Anterior angles of pronotum acute ( Fig. 16 View Figure 16 a-c). (8) Lateral pronotal margin at the level of the media-lateral fovea with an invagination ( Fig. 16 View Figure 16 a-c). (9) Males and females with strong excavated pronotum in anterior third, with pronotal disc with a large central process with “Y” shape, or one to four points ( Fig. 16 View Figure 16 a-c). (10) Elytral striae bicarinate, shallow impressed. (11) Elytral interstriae shagreened, giving the appearance of opaque (not corrugated). (12) Pygidium with complete apical margin and evident punctures ( Fig. 16f View Figure 16 ). (13) Aedeagus with slender subgenital plate ( Fig. 16i View Figure 16 ). (14) Parameres with subquadrangular shape in lateral view ( Fig. 16g View Figure 16 ) and without setae in the apical region ( Fig. 16 View Figure 16 g-i). (15) ME well sclerotized with two extensions on the right ( Fig. 16m View Figure 16 ).

Composition: Three valid species: Dichotomius bicornis ( Waterhouse, 1891) , D.diabolicus ( Harold, 1875) and D. dynastus Gandini and Aguilar, 2009 , and four undescribed species.

Geographic distribution: South Brazilian dominion (Rondônia and Yungas province), and South American transition zone ( Puna Province ) ( Fig. 15b View Figure 15 ) .