Argopistes brunneus Weise

Argopistes brunneus Weise, 1895: 336.

Argopistes sexguttatus Weise, 1895: 336. syn. nov.

Type material examined.

Holotype of Argopistes brunneus ♂: “ Madagasc. / Pipitz // Madagasc / 195 / Pipitz ” [Madagascar, Dr. Pipitz leg.] [handwritten on light blue cards] “ Argopistes / brunneus / m ” [handwritten on white card], “ HOLOTYPUS / Argopistes brunneus Weise / labelled by MNHUB ” [printed on red card], (ZMHB).

Holotype of Argopistes sexguttatus ♂: “ Madagasc. / Pipitz // Madagasc / 193 / Pipitz ” [Madagascar, Dr. Pipitz leg.] [handwritten on light blue cards] “ Argopistes / 6 - guttatus / m ” [handwritten on white card] ”, “ HOLOTYPUS / Argopistes sexguttatus Weise / labelled by MNHUB ” [printed on red card], (ZMHB).

Additional material examined.

1 spec., Madagascar Nord, Antsiranana prov., Amber Gebirge [~ 12 ° 2.20 ' S, 49 ° 15.02 ' E] (ZMHB); 1 spec., Madagascar, Toamasina prov., forêt de Fito, ex Coll. Dr. Breuning, [17 ° 59.99 ' S, 48 ° 50.50 ' E] (RMCA); 2 specs, Madagascar, Tamatave [= Toamasina, 18 ° 8.97 ' S, 49 ° 24.14 ' E] (ZMHB); 2 specs, ibid, Coll. Clavareau (RMCA); 1 spec., Madagascar, Fianarantsoa prov., Ranomafana env. [21 ° 15.76 ' S, 47 ° 27.12 ' E], 28. i – 6. ii. 1995, Ivo Jeniš leg. (BAQ).

Redescription.

Body subrounded in dorsal view, with slightly parallel sides (Fig. 1 A, C), strongly convex in lateral view; total length of body (LB) = 3.82 ± 0.13 mm (3.68 ≤ LB ≤ 3.98 mm) in male, and 3.79 ± 0.06 mm (3.72 ≤ LB ≤ 3.84 mm) in female; maximum pronotal width at the base: WP = 2.33 ± 0.05 mm (2.28 ≤ WP ≤ 2.40 mm) in male, and 2.27 ± 0.07 mm (2.20 ≤ WP ≤ 2.36 mm) in female; maximum width of elytra in the middle: WE = 3.15 ± 0.07 mm (3.08 ≤ WE ≤ 3.24 mm) in male, and WE = 3.19 ± 0.10 mm (3.04 ≤ WE ≤ 3.24 mm) in female; WE / WP = 1.35 ± 0.03 (1.32 ≤ WE / WP ≤ 1.40) in male, and WE / WP = 1.41 ± 0.04 (1.36 ≤ WE / WP ≤ 1.45) in female.

Color of the dorsal integument variable (Fig. 1 A, C): entirely black; entirely brown; with black elytral disc blending in reddish brown towards the pronotum and the elytral margins; with brown head and pronotum, and black elytra with brown patches; antennae (Fig. 1 B) yellowish; hind legs brown or paler; fore- and middle legs generally yellowish (Fig. 1 B); ventral parts mostly brownish (Fig. 1 B).

Head entirely hidden by the pronotum; vertex with very small, irregular punctation and a pair of large setiferous pores; frontal calli barely delimited, not raised; frons moderately elongate, its surface irregular, roughly wrinkled; frontal ridge elongate, thin and sharp; frontogenal sutures distinctly raised; eyes large, elongate, slightly kidney-shaped; interantennal space clearly narrower than antennal sockets. Antennae (Fig. 1 B) filiform, as long as ~ 1 / 2 the body length: LAN = 1.98 ± 0.08 mm (1.88 ≤ LAN ≤ 2.08 mm) in male, and 1.71 ± 0.08 mm (1.64 ≤ LAN ≤ 1.80 mm) in female, and LAN / LB = 0.52 ± 0.01 (0.51 ≤ LAN / LB ≤ 0.53) in male, and 0.45 ± 0.02 (0.43 ≤ LAN / LB ≤ 0.47) in female; segments 1–2 thicker; segments 3–11 slightly and gradually flattened.

Pronotum (Fig. 1 A, C) distinctly transverse: LP = 1.06 ± 0.06 mm (1.00 ≤ LP ≤ 1.12 mm) in male, and 1.05 ± 0.04 mm (1.00 ≤ LP ≤ 1.08 mm) in female, and WP / LP = 2.20 ± 0.07 (2.14 ≤ WP / LP ≤ 2.28) in male, and 2.16 ± 0.05 (2.09 ≤ WP / LP ≤ 2.20) in female; lateral margins strongly convergent anteriorly, weakly curved to straight, very weakly expanded, not visible in dorsal view; basal margin arcuate and moderately sinuate; surface smooth, sparsely micropunctate, with very dense, small punctation; surface barely raised parallel to the lateral margins, near the posterior angles; a large setiferous pore at the anterior angles. Scutellum small, subtriangular.

Elytra (Fig. 1 A, C) distinctly curved but slightly parallel in the middle third, moderately longer than wide, jointly rounded apically; lateral margins finely bordered, visible in dorsal view; surface smooth to sparsely micropunctate; main punctation mostly confused, very dense, small, slightly shallower than on pronotum but more impressed laterally; 9 (+ 1 sutural) regular lines are visible in paler specimens due to the blackened punctures (Fig. 1 A); LE = 3.38 ± 0.10 mm (3.24 ≤ LE ≤ 3.50 mm) in male, and 3.43 ± 0.09 mm (3.32 ≤ LE ≤ 3.52 mm) in female; WE / LE = 0.93 ± 0.2 (0.91 ≤ WE / LE ≤ 0.95) in male, and 0.93 ± 0.03 (0.89 ≤ WE / LE ≤ 0.98) in female; LE / LP = 3.19 ± 0.09 (3.09 ≤ LE / LP ≤ 3.32) in male, and 3.27 ± 0.16 (3.07 ≤ LE / LP ≤ 3.40) in female. Humeral calli moderately raised. Macropterous.

Prosternum with posteriorly open procoxal cavities and large intercoxal prosternal process. Mesosternum very short. First abdominal sternite approx. as long as fifth (Fig. 1 B); its central area bordered by ridges is quite narrow and subrhomboidal. Anterior and middle legs without modifications. Posterior femora greatly swollen (WF / LF = 0.68 ± 0.01), elongate-subtriangular; posterior tibiae thick, distinctly shorter than femora, apically widened and prolonged into a spur-like process on inner side; outer side of hind tibia apically toothed; apical spur of hind tibiae simple, lanceolate; first metatarsomere moderately enlarged in male.

Median lobe of the aedeagus (Fig. 1 D) with smooth surface; in ventral view is tapered towards the apex, slightly sinuate laterally; in lateral view moderately curved, with sinuate ventral outline and straight apex; dorsal ligula formed by a medially incised central lobe, and two thinner lateral lobes; its base at apical ~ 1 / 3; LAED = 1.41 ± 0.04 mm (1.36 ≤ LAED ≤ 1.48 mm); LE / LAED = 2.40 ± 0.08 (2.30 ≤ LE / LAED ≤ 2.50).

Basal part of the spermatheca (Fig. 1 E) subcylindrical, dorsally enlarged; distal part curved, elongate, uniform in thickness, with collum generally not distinguishable from the apical part; ductus subapically inserted and oriented, thin, quite short, uncoiled; LSPC = 0.38 ± 0.01 mm (0.36 ≤ LSPC ≤ 0.38 mm); LE / LSPC = 9.14 ± 0.39 (8.74 ≤ LE / LSPC ≤ 9.61).

Remarks.

Argopistes brunneus is distinguishable from the other Malagasy Argopistes species by the slightly parallel sides in dorsal view (Fig. 1 A, C), and the first abdominal sternite, whose central surface bordered by ridges is narrow and convergent posteriorly (Fig. 1 B). The median lobe of the aedeagus and spermatheca (Fig. 1 D, E) are also diagnostic. Argopistes sexguttatus Weise is here synonymized with A. brunneus, simply representing one of its chromatic forms.

Distribution.

Northern, eastern, and central Madagascar (Antsiranana, Toamasina, and Fianarantsoa provinces; Fig. 8 A). Malagasy chorotype.

Ecological notes.

Host plant unknown. Collection localities fall within areas characterized by the vegetation divisions of ‘ Malagasy Evergreen & Semi-Evergreen Forest’ and ‘ Malagasy Dry Deciduous & Evergreen Forest & Woodland’.