Deltochilum trisignatum

Silva, Fernando A. B., Louzada, Júlio & Vaz-De-Mello, Fernando, 2015, A revision of the Deltochilum subgenus Aganhyboma Kolbe, 1893 (Coleoptera: Scarabaeidae: Scarabaeinae), Zootaxa 3925 (4), pp. 451-504 : 461

trisignatum group

Description. Body. Small or medium (11–16.5 mm), weakly or strongly convex, with opaque or bright coloration in shades of black, brown, coppery, green or violet. Head. Elongate. Dorsal interocular distance approximately nine or ten times eye width (Fig. 60). Thorax. Pronotal margin, between anterior and lateral angles, oblique and slightly curved outward. Margin between lateral and posterior angles approximately straight or curved outward. Anterior and posterior portions of hypomera with dense foveiform punctures; anterior punctures rounded, posterior punctures mostly elliptical. Elytra. With punctate striae. Striae conspicuous or not. Foveiform punctures distributed evenly along the interstriae. Basal carina of seventh interstria prominent or not. Apices of interstriae 2, 3, 4, 5, 6 and 7 with tubercle or carina (that of second interstria sometimes weak or absent in D. kolbei ). Apical tubercles of 2nd, 3rd and 4th interstriae of approximately equal size and shape. Length of apical carinae of 5th and 6th interstriae approximately equal and slightly longer than apical carinae of 2nd, 3rd and 4th interstriae. Apical carina of 7th interstria longer than carina of 6th interstria. Ninth interstria completely longitudinally carinate. Elytral lateral margin completely bounded by the carina of ninth interstria (Fig. 62). Pseudepipleural carina complete (Fig. 62). First interstria usually brighter than rest of elytra. Abdomen. Punctuation of abdominal sternites concentrated anterolaterally (Fig. 73). Length of sixth ventrite, measured at midline, equal to or less than that of fifth ventrite (Fig. 73). Pygidium often acuminate at apex (Fig. 73), or rounded, with large transverse elliptical punctures. Legs. Most punctures on ventral surface of meso- and metafemora either transverse or oblique elliptical in shape (Fig. 64). Protibia abruptly expanded (Fig. 66) or not along inner margin. Metafemur clearly much wider in middle and apex than at base (Fig. 64). Apical one-third of metatibia slightly (Fig. 68) or strongly (Fig. 67) curved inward, with five or six clearly visible longitudinal carinae. Lateral carina of metatibia with a row of medium-size setae denser in apical half. Metatarsus much shorter or approximately two-thirds of metatibia length. Secondary sexual characters. Head of male sometimes slightly more triangular than that of female. Male abdomen usually slightly concave at lateral view, that of female usually convex. Male ventrites more flattened antero-posteriorly than that of female. Abdominal suture separating 6th from 5th ventrite usually curved in male (Fig. 73) and nearly straight in female. Apical margin of pygidium usually distended in male. Protibial spurs generally vary in shape and size between male and female of some species. Aedeagus. Parameres symmetrical, short, simple, without ornamentation or setae, and wider at base than at apex ( Figs 4–9 ). Endophallus: with lobe in submedial portion. Lamella copulatrix: left lobe "J" shaped, right lobe “baton” shaped (Figs 33–35). Superior right peripheral sclerite (SRP): circular shaped, cable "n" shaped, and ring with margin "thread" shaped (Figs 42–44). Fronto-lateral peripheral sclerite (FLP): two irregular sclerites, with a sclerotized cover that surrounds it (Figs 50–52). Complex of axial and subaxial sclerites (A+SA): several superposed and elongate sclerites (Fig. 59). Genital segment: with lateral sclerotized arms in roughly a scalene triangle; central portion approximately "M" shaped, showing portions with different degrees of sclerotization; superior margin well delimited, with conspicuous sclerotization (Figs 25, 26, 27).

Diagnosis. Compared to the valgum group, the diagnostic characters of trisignatum group are: Dorsal interocular distance approximately nine or ten times eye width (Fig. 60); apical tubercle of the 2nd, 3rd and 4th interstriae with approximately equal size and shape (that of second interstria absent or weak in D. kolbei ); length of apical carinae of 5th and 6th interstriae approximately equal to or slightly longer than apical carinae of 2nd, 3rd and 4th; ninth interstria completely longitudinally carinate (Fig. 62); elytral lateral margin bounded by the carina of ninth interstria (Fig. 62); ventral surface of meso and metafemora with transverse or oblique elliptical punctures (Fig. 64); lamella copulatrix (LC): left lobe “J”-shaped and right lobe baton-shaped (Figs 33–35); cable of superior right peripheral sclerite (SRP) "n"-shaped, and ring with margin “thread”-shaped (Figs 42–44); superior margin of genital sclerite well-defined, with conspicuous sclerotization (Figs 25–27).

Figures

FIGURES 4 – 11. Aedeagus in Deltochilum (Aganhyboma). 4. D. titovidaurrei new species. 5. D. cupreicolle. 6. D. viridescens new status. 7. D. viridicatum new species. 8. D. amandaarcanjoae new species. 9. D. trisignatum. 10. D. cangalha new species. and D. alpercata new species. 11. D. finestriatum new species. Figures scale = 1 mm.