Dichotomius (Dichotomius) bitiensis ( Gillet,1911 )

1. Dichotomius (Dichotomius) bitiensis ( Gillet,1911) View in CoL species group

Diagnosis: The species of theD. bitiensis species group are recognized by the following combination of characters:(1) small-sized to medium-sized individuals (12.1–20.2 mm).(2) Head oval to subtriangular in males, and subtriangular in females ( Fig.5 View Figure 5 a-d). (3) Clypeus with inconspicuous clypeal teeth, sometimes not perceptible by the clypeal projection ( Fig. 5 View Figure 5 a-d). Clypeal surface with well-defined transverse wrinkles. (4) Ventral clypeal process conical with obtuse tip ( Fig. 5f View Figure 5 ). (5) Both sexes with a cephalic process in the fronto-clypeal region, which may be a transverse carina, or a conical process with simple or bicuspidtip ( Fig.5 View Figure 5 a- d). (6) Protibial spur abruptly angle downward near the apex ( Fig. 5e View Figure 5 ). (7) Pronotum from simple and convex at most with two very weak and transversal concavities to strongly excavated with pronotal processes of four humps that can be the two largest central or the four of equal size ( Fig. 5 View Figure 5 a-d). (8) Elytral striae bicarinate, from shallow to distinctly impressed, though the latter with deep punctures along their entire extension. (9) Pygidium with complete or incomplete apical margin and variable surface punctures ( Fig. 5g View Figure 5 ). (10).Aedeagus with subgenital plate, with widened plates ( Fig.5j View Figure 5 ). (11) Parameres subtriangular in lateral view ( Fig. 5h View Figure 5 ), with short to long setae in the apical area ( Fig. 5 View Figure 5 h-j). (12) ME subquadrangular,semi-sclerotized in the central area and well sclerotized around it, with two projections and two lobes that have raspules on the surface in different extensions that vary among species ( Fig. 5n View Figure 5 ).

Composition: Five valid species: Dichotomius bitiensis ( Gillet, 1911) , D. costaricensis ( Luederwaldt, 1935) , D. latilobatus Boilly and Vaz-de-Mello, 2021, D. motai ( Pereira, 1942a) , D. nitidissimus ( Waterhouse, 1891) and one undescribed species.

Geographic distribution: Pacific dominion (Guajira, Sabana and Puntarenas-Chiriquí provinces), Boreal Brazilian dominion (Guianan lowlands and Roraima provinces), South Brazilian dominion (Madeira, Rondônia and Yungas provinces), Chacoan dominion (Cerrado and Chaco provinces), Paraná dominion (Parana forest province), and South American Transition zones ( Páramo province ) ( Fig. 6a View Figure 6 ) .