Deltochilum valgum
Creators: name: Silva, Fernando A. B.
name: Louzada, Júlio
name: Vaz-De-Mello, Fernando
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Deltochilum
Deltochilum valgum

description: valgum group
Description. Body. Dorsal surface with foveiform punctures of variable size and density. Head, pronotum, elytra and ventral surface with a black, copper or red coloration, with or without reddish, brownish, greenish sheen or copper tones. Length 12 to 16.5 mm. Head. Surface with strong, deep and dense punctures (Fig. 61), almost confluent in some species. Foveiform punctures of head with well-defined margin (Fig. 61). Margin of head, near clypeal teeth, straight and followed by a small tooth slightly pronounced (Fig. 61). After this tooth, margin slightly curved inward until the junction of clypeus with gena. Dorsal interocular distance approximately three or four times eye width (Fig. 61). Thorax. Margin between anterior and lateral angles elongate and oblique (Fig. 85), approximately straight, with visible row of setae in dorsal view. Margin between lateral and posterior angles straight or slightly rounded (curved outward). Posterior margin, after the posterior angle, slightly curved outward. Pronotum surface with deep and dense foveiform punctures. Punctures smaller and more dispersed near the anteromedial portion of pronotum (Fig. 85). Hypomera with foveiform punctures denser on anterior portion and somewhat more dispersed on posterior portion (Figs 81–83). Elytra. Oval shape, irregular surface (slightly rugose) and lateral margins ranging from semi-parallel to convex. Striae thick and well delimited (Fig. 75) or narrow and almost inconspicuous (Fig. 74). Interstriae ranging from distinctly convex to flattened, with uniform punctures along the width (Fig. 75), or more punctate on the sides, close to striae (Fig. 86). Interstriae of most species with ocellate punctures (microtubercles), or shiny and glossy zones poorly defined amid foveiform punctures (Figs 74–77). Basal carina of seventh interstria short or elongate. Basal carina of ninth interstria, when present in threequarters of elytra, can reach the anterior limit of apical carina of seventh interstria. Basal carina of ninth interstria never traverses the entire length of elytra (Fig. 63). In some species, basal carina of ninth interstria reaches no farther than mid length of elytra (Fig. 80). Posterior part of elytral lateral margin formed by the pseudepipleural carina (Fig. 80). Apices of interstriae 2, 3, 4, 5, 6 and 7 with tubercle or carina. Apical carina of second interstria absent in some species. Apical carina of third interstria can be more evident than apical carinae of second and fourth interstriae (Fig. 88); species which this carina is more evident, it presents a rounded form, resembling a tubercle. Length of apical carina of sixth interstria longer than or equal to that of apical carina of fifth interstria. Pseudepipleural carina complete, visible entire length of epipleuron in most species (Fig. 63); in some species this carina may be interrupted at basal third, reappearing next to one-half of elytral length (Fig. 80). Abdomen. Punctures large and conspicuous on lateral portion of ventrites; sparser or absent along midline. Punctures reduced on medial portion to one row on anterior margin. Length of sixth ventrite, measured at midline, longer than that of fifth ventrite. Pygidium with dense rounded punctures over entire surface. Apex of pygidium acuminate. Legs. Most foveiform punctures of the metafemur rounded and dense (Fig. 65). Anterior edge of profemur completely emarginate. Protibia not abruptly widened, with dense foveiform punctures from base to first tooth. Medial lateral tooth of protibia closer to apical tooth than to basal tooth. Metafemora just slightly narrowed at base (Fig. 65). Apical third of metatibia strongly curved inward (as in Fig. 67). Inner margin of metatibia without longitudinal row of small tubercles, or tubercles inconspicuous. Metatarsus with approximately one-half of metatibia length. Secondary sexual characters. Male abdomen more longitudinally flattened than that of female. Males with a small tubercle at medial portion of abdomen between first and second ventrites. Protibial spur broader and more curved in male. Inner margin of metatibia usually with a longitudinal row of small tubercles more conspicuous in male. Aedeagus. Parameres symmetrical, simple, without ornamentation or setae, elongate or short (Figs 10–23). Endophallus: lobe in submedial portion. Lamella copulatrix (LC): subrectangular or subtrapezoidal sclerites (Figs 36–41). Superior right peripheral sclerite (SRP): circular shaped, sub-straight cable and a small sclerotized appendix. Ring with margin usually narrow, but never "thread"-shaped (Figs 45–49). Fronto-lateral peripheral sclerite (FLP): two irregular sclerites with a sclerotized cover that surrounds it (Figs 53–58). Complex of axial and subaxial sclerites (A+SA): several superposed and elongate sclerites. Genital segment: lateral arms sclerotized in a scalene triangle shape; central portion “M”-shaped; superior margin weakly bounded, with weak sclerotization (Figs 28–32).
Diagnosis. Compared to the trisignatum group, the diagnostic characters of valgum group are: Presence of small clypeal teeth external to central teeth (Fig. 61); foveiform punctures of pronotal disc smaller than that of lateral portion; posterior part of elytral lateral margin formed by the pseudepipleural carina (Figs 63, 80); lamella copulatrix: subrectangular or subtrapezoidal sclerites (Figs 36–41); ring of superior right peripheral sclerite (SRP) with thick and regular margin, never similar to a “thread” (Figs 45–49); SRP with a small appendix (Figs 45–49).
description: Published as part of Silva, Fernando A. B., Louzada, Júlio & Vaz-De-Mello, Fernando, 2015, A revision of the Deltochilum subgenus Aganhyboma Kolbe, 1893 (Coleoptera: Scarabaeidae: Scarabaeinae), pp. 451-504 in Zootaxa 3925 (4) on pages 470-471, DOI: 10.11646/zootaxa.3925.4.1, http://zenodo.org/record/244795