Dichotomius (Dichotomius) carolinus ( Linnaeus, 1767 )

5. Dichotomius (Dichotomius) carolinus ( Linnaeus, 1767) View in CoL species group

Diagnosis: The species of the D. carolinus species group is recognized by the following combination of characters:(1) Large-sized individuals (23.7–32,1 mm). (2) Head long that wide, subtriangular to oval in males and subtriangular in females ( Fig. 11a, b View Figure 11 ). (3) Clypeus without clypeal teeth and with strong and well-defined transverse wrinkles ( Fig. 11a, b View Figure 11 ). (4) Ventral clypeal process conical with obtuse to acute tip ( Fig.11c View Figure 11 ). (5) Males with one or two cephalic processes; when they have a single process, it is a transverse bicuspid carina or a widened bicuspid horn in the fronto-clypeal region. If they have two in addition to the previous one, another simple one in the clypeus.(6) Females with a four-pointed process between the eyes ( Fig. 11b View Figure 11 ). (7) Protibial spur not angled or slightly angled near the apex ( Fig. 11d View Figure 11 ). (8) Both sexes with excavated pronotum in anterior third, with pronotal disc with a large central lobe as wide as the head, with triangular to rounded shape, the lobe continues on each side to the lateral region where it forms two minor processes on the lateral fovea ( Fig. 11a, b View Figure 11 ). (9) Elytral striae bicarinate shallow to distinctly impressed, with shagreened surface and ocellate punctures. Elytral striae from 1st to 5th widened in the apical area ( Fig. 11a, b View Figure 11 ). (10) Pygidium with incomplete apical margin and evident puncture ( Fig. 11e View Figure 11 ). (11). Aedeagus with subgenital plate ( Fig. 11h View Figure 11 ). (11) Parameres subtriangular in lateral view ( Fig. 11f View Figure 11 ), with very long setae in the apical area ( Fig. 11 View Figure 11 f-h). (13) ME medium to large, subquadrangular with two extensions on the right and setae present throughout the surface. ( Fig. 11l View Figure 11 ).

Composition: Eigth valid species: Dichotomius amicitae Kohlmann & Solis, 1997 , D. annae Kohlmann & Solis, 1997 , D. camargoi Martínez, 1956 , D. carolinus ( Linnaeus, 1767) , D. coenosus Erichson, 1848 , D. colonicus ( Say, 1835) , D.longiceps ( Taschenberg, 1870) , D.maya Peraza and Deloya, 2006 , and D. nevermani ( Luederwaldt, 1935), and one undescribed species.

Geographic distribution: Mexican transition zone (all provinces), Brazilian subregion Mesoamerican dominion (all provinces), Pacific dominion (Chocó-Darién, Guajira, Guatuso-Talamanca, Magdalena, Puntarenas-Chiriquí, Sabana, and Venezuelan provinces), Boreal Brazilian dominion (Guianan Lowlands, Guianan, and Pará provinces), South Brazilian dominion (Madeira, Rondônia, and Yungas provinces), Chacoan subregion Southeastern Amazonian dominion ( Xingu-Tapajós province ), Chacoan dominion ( Cerrado province ), Paraná dominion ( Araucaria Forest , Atlantic, and Parana Forest provinces), and South American transition zone (Páramo and Puna provinces) in the Neotropical region .This species group reaches to the Nearctic region in the Western subregion ( Rocky Mountain dominion, Chihuahuan province ) and Alleghany subregion ( Escalante et al., 2021) ( Fig. 12a View Figure 12 ) .