Dichotomius (Selenocopris) berthalutzae Valois, Silva

Valois, Marcely C., Silva, Fernando A. B. & Vaz-de-Mello, Fernando Z., 2022, A taxonomic revision of the globulus species group of Dichotomius Hope, 1838 (Coleoptera: Scarabaeidae: Scarabaeinae), Journal of Natural History 56 (1 - 4), pp. 119-147 : 129-131

Dichotomius (Selenocopris) berthalutzae Valois, Silva and Vaz-de-Mello sp. nov.

( Figures 1 (b), 3(i–j), 4(c–d), 5(c, i), and 6)

Etymology

Named after Bertha Lutz (1894–1976), a Brazilian diplomat, politician and zoologist, for her contributions to Brazilian science in the early twentieth century.

Diagnosis

Dichotomius berthalutzae sp. nov. is suggested to be closely related to the South American species D. fortepunctatus and the Central American D. gamboaensis . All these species have a distinct pre-apical longitudinal carina on the dorsal surface of the paramera ( Figure 4 (c, d,g–j)), and the ME with two well-developed hook-like projections separated by a broad C-shaped emargination ( Figure 5 (c,f,g)). However, in comparison with D. fortepunctatus and D. gamboaensis , the new species has a shorter longitudinal carina on the paramera, which is approximately one-third of the total length of the paramera in dorsal view, whereas in the other two species the carina is approximately one-fourth ( D. fortepunctatus ) or half ( D. gamboaensis ) of the paramera length. Externally, D. berthalutzae can be distinguished from the other two species by its smaller body size (10–11 mm); surface of head with different-sized ocellate punctures, more sparsely distributed on anterior clypeal region; surface of elytral interstriae shagreened, with dense smooth dots medially ( Figure 3 (i)); mesofemora with a longitudinal groove along the whole posterior margin; sixth abdominal ventrite of male twice longer than fifth ( Figure 3 (j)); and pygidium of male rounded at the apex.

Description (male)

Body length: 10–11 mm. Dorsum black, barely shiny. Head: clypeal edge bidentate, teeth acute, separated by a deep V-shaped emargination. Head with ocellate punctures spaced at most by the diameter of a puncture, except on anterior region of the clypeus, which has ill-defined transverse wrinkles. Cephalic process produced into a small central tubercle. Antennal club with light brown tumescence. Thorax: pronotum approximately twice wider than long. Anteromedian region of the disc with a shallow central excavation. Surface of the disc with dense ocellate punctures equally spaced by half their diameter. Surface of hypomera completely covered with ocellate punctures; anterior and lateral regions with punctures bearing short orange setae. Prosternum filled with ocellate punctures. Mesoventrite covered with ocellate punctures, usually bearing short orange setae. Metaventrite surface with ocellate punctures, except on disc; punctures on anterior region usually bearing short setae. Meso-metaventral suture distinct. Anterior region half the length of metafemora. Mid-longitudinal sulcus feebly marked posteriorly. Lateral regions of metaventrite with ocellate punctures larger than those on anterior region. Elytra: convex medially in lateral view. Humeral callus distinct. Striae thin, punctate; punctures wider than striae, spaced by 3 times their diameter in the elytral disc ( Figure 3 (i)). Interstriae I–VII distinctly convex. Legs: protibial spur curved at apical fifth. Metatibial spur deeply emarginate apically. Ventral surface of the profemora covered with coarse setiferous punctures along entire extension, setae very short. Ventral surface of the mesofemora with coarse punctures at apical third. Ventral surface of the metafemora with coarse punctures, concentrated on apical half; basal half with sparse, scattered punctures. Metafemora bearing a thin longitudinal groove along whole extension of posterior margin, wider on apical half. Abdomen: ventrites covered with ocellate punctures at lateral regions, punctures at medial region restricted to a single row along anterior edge. Pygidium approximately twice wider than long, convex medially. Pygidial disc covered with ocellate punctures, spaced by at least their diameter. Apex of the pygidium margined. Tegmen: in dorsal view, paramera rectangular in shape, twice longer than its width medially, apex truncate ( Figure 4 (c,d)). Longitudinal carina on dorsal surface of paramera serrate along its margin ( Figure 4 (c)). In dorsal view, inner edges close to each other at basal third ( Figure 4 (c)). Ventral sclerotised membrane between paramera thinner at basal half; lateral margins angulate at anterior half ( Figure 4 (d), arrow). Endophallus: inferior projections of ME separated by a broad U-shaped emargination ( Figure 5 (c)). ME with a longitudinal fold at the median superior region ( Figure 5 (c)). A and SA endophallites thin, C-shaped in lateral view; SA endophallite with reticulate texture inferiorly ( Figure 5 (i)). FLP endophallite C-shaped in lateral right view, inferior region shorter than superior one; surface of the C-shaped region with irregular projections ( Figure 5 (i)). SRP endophallite approximately J-shaped ( Figure 5 (i)). Female: differs from male by the clypeal teeth larger and acute. Clypeal surface with distinct transverse ridges. Sixth abdominal ventrite about twice longer than fifth medially and bearing a small central knob. Pygidial disc strongly convex in lateral view.

Type material examined

Holotype: COLOMBIA: Valle Del Cauca. La Fragua . Valle R[io] Cajambre C.N.F. 28 August– 01–September 1993. L.C. Pardo Locarno (1♂ CEMT).

Paratypes [79♂♂ 32♀♀]: COLOMBIA: Chocó: Acandí, Corregimiento de Capurganá . Jardín Botánico. Bosque Húmedo Tropical. 8.628°N, - 77.353°W, 30 m. 16–18 January 2008. Pitfall with human faeces. J. Arias, P. Delgado and A. González (43♂♂ 41♀♀ CEMT). Same data but (10♂♂ 10♀♀ ECC). Same but Sapzurro. Bosque Húmedo Tropical. 8.639°N, - 77.354°W. 63 m. 15–17 January 2008. Pitfall with human faeces. J. Arias, P. Delgado and A. González (20♂♂ 20♀♀ CEMT). Same data but Corregim, Capurganá Camino ‘ Al Cielo’ . 10 m. 6 January 1999. A. Vitolo (1♂ 1♀ CEMT); PNN Enseada de Utria . 10 June–3 July 1997. Llanos-Jurado (1♂ CEMT); Lloró . R. Atrato C.N.F. 5–8 January 1993. L. C. Pardo Locarno (1♂ CEMT); same data but 90 m. 5.500°N, - 76.5166°W. 02–May. J. Noriega (1♂ CEMT); Valle Del Cauca. La Fragua. Valle R[io] Cajambre C.N.F. 28–August–01–September–1993. L.C. Pardo Locarno (1♂ CEMT); Amazonas: Leticia . 70 m. October 2005. J. Noriega (1♂ CEMT) .

Figures

Figure 1. Dorsal habitus of male. (a) Dichotomius benesi; (b) D. berthalutzae sp. nov.; (c) D. femoratus; (d) D. fortepunctatus; (e) D. gamboaensis.

Figure 3. Detailed morphology of the species in the globulus group. (a) Ventral view of male, Dichotomius femoratus; (b) ventral view of male, D. gamboaensis; (c) male head, D. fortepunctatus; (d) female head, D. gamboaensis; (e) pronotum of male, D. femoratus; (f) pronotum of male, D. fortepunctatus; (g) elytral striae of male, D. fortepunctatus; (h) elytral striae (Estria) of male (ShMicro, shagreened microsculpture), D. femoratus; (i) elytral striae of male, D. berthalutzae sp. nov.; (j) male abdominal ventrites in ventral view, D. berthalutzae sp. nov.; (k) male abdominal ventrites in ventral view, D. femoratus; (l) female abdominal ventrites in lateral view, D. femoratus.

Figure 4. Tegmen, dorsal and ventral views,respectively. (a,b) Dichotomius benesi; (c,d) D. berthalutzae sp. nov.; (e,f) D. femoratus; (g,h) D. fortepunctatus; (i,j) D. gamboaensis. Scale bar: 500 µm

Figure 5. Endophallites. (a) Dichotomius benesi, endophallus with endophallites, dorsal view. Medial endophallite: (b) D. benesi; (c) D. berthalutzae sp. nov.; (d,e) D. femoratus; (f) D. fortepunctatus; (g) D. gamboaensis. Accessory endophallites: (h) D. benesi; (i) D. berthalutzae sp. nov.; (j) D. femoratus; (k) D. fortepunctatus; (l) D. gamboaensis. Abbreviations: FLP, fronto-lateral peripherical endophallite; A +SA, subaxial and axial endophallites; SRP, superior-right peripheral endophallite.