Chinavia difficilis (Stål), Stal

Genevcius, Bruno C., Grazia, Jocelia & Schwertner, Cristiano F., 2012, Cladistic analysis and revision of the obstinata group, genus Chinavia Orian (Hemiptera: Pentatomidae), Zootaxa 3434, pp. 1-30 : 24-25

Chinavia difficilis (Stål)

( Figs. 1 , 7b , 12a , 23a , 24b , 25b , 26 and 27 ; Tables 1 , 2 and 4 )

Rhaphigaster difficilis Stål, 1860: 23 ; Walker, 1867: 360.

Nezara difficilis ; Stål, 1872: 42; Distant, 1887: lxiii; Lethierry & Severin, 1893: 165. Nezara (Acrosternum) difficilis ; Kirkaldy, 1909: 118.

Acrosternum difficilis ; Link & Grazia, 1983: 124.

Acrosternum (Chinavia) difficile ; Rolston, 1983: 106, 123-124; Frey-da-Silva & Grazia, 2001: 110 Acrosternum difficiles [sic]; Link & Grazia, 1987: 117.

Chinavia difficilis ; Schwertner & Grazia, 2006: 243; 2007: 422, 426.

Diagnosis. Body without black spots on pronotum, cicatrices, scutellum, basal angles or connexivum ( Fig. 27 ). The spiracles are dark and the medial spine of third urosternite never surpasses the mesocoxae; these characters distinguish C. difficilis and C. napaea from C. obstinata . Antennae entirely green, anterolateral margins of pronotum without submarginal dorsal depression, and gonocoxites 8 not strongly convex separate C. difficilis from C. napaea .

Coloration. Body predominantly green, except for a thin yellowish longitudinal band on the ventral lateral margins of urosternites.

Head. Margins of juga with a slight concavity in front of eyes, apex of head broadened and semicircular ( Fig. 27 ). Proportion of antennal segments: I<II<III<IV≈V. Rostrum surpassing the mesocoxae and sometimes reaching the posterior coxae. Proportion of rostrum segments: I≈II>III>IV.

Thorax. Anterolateral margins of pronotum without submarginal dorsal depression. Hemelytra with costal angles of corium slightly obtuse. Sutural membrane convex.

Abdomen. Medial spine of third urosternite never surpassing mesocoxae. Spiracles black.

Male genitalia as in Fig. 23a and 24b . Posterolateral angles of pygophore well projected, extending beyond the posterior margin of segment X, tapering at the apex. Median excavation of the ventral rim slightly concave. Genital cup moderately excavated. Flaps of the ventral rim moderately infolded over the genital cup.

Female genitalia ( Figs. 25b and 26 ). Gonocoxites 8 flat. Pars intermedialis conical; diameter of capsula seminalis twice the diameter of pars intermedialis. Processes of capsula seminalis subequal in length and subrectilineal, three times the length of pars intermedialis ( Fig. 26 ).

Distribution. Brazil: Rio de Janeiro, São Paulo and Santa Catarina.

Material examined. Rhaphigaster difficilis Stål, 1860 , holotype: BRASIL: Rio de Janeiro (♀, NRM). Additional material. BRAZIL: Rio de Janeiro [ Guanabara ]: RJ, 1955, Zajciv (1♀, MNRJ); Rio de Janeiro [ Guanabara ]: RJ, X.1963, M. Alvarenga (131♀, NMNH); Rio de Janeiro [ Guanabara ], Represa Rio Grande I.1969, F.M. Oliveira (13, AMNH); Rio de Janeiro [ Guanabara ], Represa Rio Grande , M. Alvarenga & F.M. Oliveira, I.1972 (13, AMNH); Rio de Janeiro [ Guanabara ]: Represa Rio Grande VII-VIII.1972, M. Alvarenga (131♀, AMNH); Rio de Janeiro, Silva Jardim , March 1974, F.M. Oliveira (131♀, AMNH); Rio de Janeiro [ Guanabara ]: Represa Rio Grande , XII.1977 (233, AMNH); Caraguatatuba, SP, 2.IV.1962, Reichardt & Silva (1♀, DZRS); Rio nov ., PR Uhler collection (1♀, NMNH); Criciuma , SC, 28.IX.2007, Bianchi, F.M. (13, DZRS); Criciuma , SC, 8.XI.2007, Bianchi, F.M. (1♀, DZRS); Criciuma , SC, 23.XI.2007, Bianchi, F.M. (1♀, DZRS); Criciuma , SC, 7.II.2008, Bianchi, F.M. (13, DZRS).

Figures

FIGURE 1. Distribution of obstinata group. Green, Chinavia difficilis; red, C. obstinata; yellow, C. napaea. Dark gray, Brazilian Atlantic Forest; light gray, Pampa biome.

FIGURE 7. Yellowish dots (yd) on the scutellum basal margin: well marked in Chinavia rinapsa (a), slightly marked in C. difficilis (b).

FIGURE 12. Shape of gonocoxites 8 (gc8): flat in C. difficilis (a), convex in C. napaea (b).

FIGURE 23. Ventral view of pygophore: C. difficilis (a), C. obstinata (b), showing flaps (fl) and genital cup (gc).

FIGURE 24. Posterior view of pygophores: C. obstinata (a) and C. difficilis (b), showing “V-shaped” median excavation (me).

FIGURE 25. Ventral view of female genitalia: C. obstinata (a), C. difficilis (b) and C. napaea (c), showing gonocoxites 8 and 9 (gc8 and gc9), laterotergites 8 and 9 (la8 and la9), segment X (X), sutural angles (sa) and excavations (ex) on the posterior margins of gonocoxites 8 of C. napaea (c).

FIGURE 26. Ectodermic ducts (internal female genitalia): C. difficilis, showing posterior and anterior annular flanges (paf and aaf), pars intermedialis (pi), capsula seminalis (cs) and processes of capsula seminalis (pcs).

FIGURE 27. Dorsal and ventral view of C. difficilis (Holotype, ♀).