Dichotomius (Dichotomius) mormon ( Ljungh, 1799 )

10. Dichotomius (Dichotomius) mormon ( Ljungh, 1799) View in CoL species group

Diagnosis: This species group was revised by Arias-Buriticá and Vaz-de-Mello (2024b). The species of the D. mormon species group are recognized by the following combination of characters: (1) medium-sized to large-sized individuals (11.4–28.5 mm). (2) Head oval and twice as wide as it is long ( Fig. 19a, b View Figure 19 ). (3) Clypeus with two inconspicuous clypeal teeth, sometimes imperceptible ( Fig. 19b View Figure 19 ). (4) Ventral clypeal process with triangular appereance with acute or obtuse tip ( Fig. 19c View Figure 19 ). (5) Males with lamellar process in the anterior region of head ( Fig. 19a View Figure 19 ). (6) Females with conical process in the fronto-clypeal region ( Fig. 19b View Figure 19 ). (7) Protibial spur without angle near apex ( Fig. 19d View Figure 19 ). (8) Pronotum with strong excavation in the anterior area, pronotal disc with processes 2-6 pointed in males and 2-4 pointed in females ( Fig. 19a, b View Figure 19 ). (9) Anterior margin of pronotum behind head with a single lobe ( Fig. 19a View Figure 19 ). (10) Elytral striae bicarinate, shallow to distinctly impressed. (11) Pygidium with complete apical margin and evident punctures ( Fig. 19e View Figure 19 ). (12). Aedeagus with widened subgenital plate ( Fig. 19h View Figure 19 ). (13) Parameres subtriangular in lateral view ( Fig. 19f View Figure 19 ), without setae in the apical region ( Fig. 19 View Figure 19 f-h). (14) ME well sclerotized, large, and asymmetrical ( Fig. 19l View Figure 19 ).

Composition: Five valid species: Dichotomius conicollis (Blanchard, 1846) , D. larseni Arias-Buriticá and Vaz-de-Mello, 2024, D. mormon ( Ljungh, 1799) , D. ohausi ( Luederwaldt, 1923) , and D. talaus ( Erichson, 1847) .

Geographic distribution: Boreal Brazilian dominion (Imerí and Napo provinces), South Brazilian dominion (all provinces), and Paraná dominion (Araucaria, Atlantic, Paraná Forest and Southern Espinhaço provinces) ( Fig. 18b View Figure 18 ) .