Dichotomius (Selenocopris) gamboaensis Howden and Young 1981
Creators: name: Valois, Marcely C.
name: Silva, Fernando A. B.
name: Vaz-de-Mello, Fernando Z.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Dichotomius
Dichotomius gamboaensis

description: Dichotomius (Selenocopris) gamboaensis Howden and Young, 1981
(Figures 1 (e), 3(b,d), 4(i,j), 5(g,l) and 6))
Dichotomius gamboaensis Howden and Young, 1981: 128; Krajcik 2006: 54; 2012: 91; Kohlmann and Solís 1997: 362; 364; 366; Vaz-de-Mello and Nunes 2016: 299.
Diagnosis
Dichotomius gamboaensis and D. berthalutzae sp. nov. share the following combination of characters: pronotal disc covered with umbilicate punctures (Figure 1 (b,e)); elytral interstriae with shagreened microsculpture and distinct smooth dots along medial region (as in Figure 3 (i)); dorsal surface of paramera with a longitudinal carina at least as long as onethird of paramera in dorsal view (Figure 3 (c,d,i,j)); and hook-like projections on inferior part of ME separated by a C-shaped emargination (Figure 5 (c,g)). However, D. gamboaensis can be distinguished from D. berthalutzae sp. nov. by the clypeofrontal region with a central, apically bifurcate knob; anterior declivity of the pronotum onefourth as long as pronotal disc; abdominal ventrites narrowed medially (Figure 3 (b)); and male with pygidium rounded at apex.
Redescription (male)
Body length: 13–14 mm. Dorsum black, barely shiny (Figure 1 (e)). Head: clypeal edge bidentate, teeth rounded, separated by a shallow V-shaped emargination. Clypeogenal junction rounded, shallowly nochted. Surface with different-sized ocellate punctures, more sparsely distributed on anterior clypeal region. Clypeogenal suture present. Cephalic process produced into a small central tubercle. Antennal club with light brown tumescence. Thorax: pronotum approximately twice wider than long (Figure 1 (e)). Pronotal disc convex, anteromedian region with a shallow central excavation; surface of the disc with dense ocellate punctures equally spaced by half their diameter, punctures on anterior angle more sparse. Whole surface of hypomera 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. Lateral region of metaventrite with ocellate punctures, disc smooth; on anterior region, punctures usually bearing short setae. Meso-metaventral suture distinct. Anterior region of metaventrite as wide as two-thirds the length of metafemora. Mid-longitudinal sulcus indistinct. Lateral lobes of metaventrite with ocellate punctures larger than those on anterior region. Elytra: slightly convex in lateral view. Humeral callus distinct. Striae thin and with ill defined punctures, spaced by twice their diameter. Interstriae I–VII convex, barely shiny. Legs: protibial spur curved at apical fifth. Metatibial spur deeply emarginate apically. Ventral surface of the profemora covered with coarse setiferous punctures over their entire extension. Ventral surface of the mesofemora with ocellate puncture at apical third, near trochanter. Ventral surface of the metafemora with ocellate punctures at apical half. Meso and metafemora bearing a thin longitudinal groove along posterior margin, wider on apical half. Abdomen: sixth ventrite twice longer than fifth. Ventrites covered with ocellate punctures at lateral regions, punctures at medial region in a single row along anterior edge. Pygidium longer than wide, convex medially. Surface of the pygidial disc with ocellate punctures concentrated along anterior half, and spaced by half their diameter. Apex of the pygidium margined. Tegmen: in dorsal view, paramera rectangular, twice longer than its width medially, apex rounded; inner edges close to each other at basal third (Figure 4 (i)). Apical half significantly narrower than base in lateral view. Dorsal surface of paramera with a strong pre-apical longitudinal carina at approximately apical half; margin of the carina serrate (Figure 4 (i)). Ventral sclerotised membrane between paramera thinner at basal third; angulate at lateral portions (Figure 4 (j)). Endophallus: ME inferior projections separated by a broad C-shaped emargination (Figure 5 (g)). ME with a longitudinal fold at the median superior region (Figure 5 (g)). A and SA endophallites thin, C-shaped in lateral view; SA endophallite with reticulate texture inferiorly (Figure 5 (l)). 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 (l)). SRP endophallite approximately V-shaped (Figure 5 (l)). Female: differs from male by clypeal teeth larger and acute, separated by V-shaped emargination. Pronotum lacking anterior declivity or distinct mid-longitudinal sulcus. Lateral teeth of the protibia larger. Pygidial disc swollen and sparsely punctate. Sixth abdominal ventrite 3 times longer than fifth.
Type material examined
Holotype of Dichotomius gamboaensis ♂ [USNM]: ‘ Panama. Canal Zone / Gamboa /Limbo Hunt Club. 23–24.X.1975 OPYoung. Tapir feces trap’ // ‘ HOLOTYPE Dichotomius (L.) gamboensis sp. nov’.
Additional material examined
PANAMA: Prov. Cerro Azul: (850 m). 17 July 1998. M. Hardy (1♀ CEMT); Cocle: El Valle. H. Campestre. 600 m. 24 May 1999. D. Curoe (1♂ 3♀♀, CEMT).
description: Published as part of 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), pp. 119-147 in Journal of Natural History 56 (1 - 4) on pages 137-139, DOI: 10.1080/00222933.2022.2046887, http://zenodo.org/record/6530252