Lincus incisus Rolston, 1983

Maciel, Aline S., Garbelotto, Thereza de A., Winter, Ingrid C., Roell, Talita & Campos, Luiz A., 2015, Description of the males of Lincus singularis and Lincus incisus (Hemiptera: Pentatomidae: Discocephalinae), Zoologia 32 (2), pp. 157-161 : 159-160

Lincus incisus Rolston, 1983

Figs. 10-18

Lincus incisus Rolston, 1983: 1 , 3, 4, 9-10, Figs. 8-9 (female holotype from De Mapane, Suriname, deposited in RMNH, not examined, no paratypes); Campos & Grazia, 2006: 153 (list).

Description of the male. The fuscous general color of male and its general morphology, including the anterolateral margins of pronotum expanded in obtuse angle, posterior to pronotal lobes, are as described for females by ROLSTON (1983) (Fig. 10). Genitalia. Pygophore subrectangular. Surface with short setae. Dorsal rim concave, bearing setae lateral to segment X ( Fig. 11 , dr). Posterolateral angles obtuse ( Fig. 11 , pa), depressed, with 1+1 median projections ( Fig. 11 , mp). Segment Xsclerotized, ventrally directed; apex expanded and flattened ( Fig. 11 , X); anal opening circular, and genital opening in longitudinal slit, both at ventral surface ( Fig. 12 ). Ventral rim concave, with setae along the margin, medially carinated ( Fig. 12 , vr). Ventral surface tumescent on disc, with 1+1 lateral sulci following ventral rim ( Fig. 12 , t). Parameres inconspicuous, attached to the articulatory apparatus of phallus, subrectangular and with an apical tuft of setae ( Figs. 13-15 ). Phallus. Phallotheca globose, strongly sclerotized ( Figs. 16-18 , ph). Vesica elongated, medially narrowed, longer than the combined lengths of phallotheca and ductus seminis distalis ( Figs. 16-18 , v); with one globose dorsal projection posteriorly directed ( Figs. 16-18 , dp); 1+1 lateral globose projections, posteriorly directed ( Figs. 16-18 , lp); posterior projection truncated, bearing ductus seminis distalis ( Figs. 16-18 , pp). Ductus seminis distalis antero-dorsally arched toward the projections of vesica ( Fig. 18 , ds).

Measurements (n = 3). Total length 12.55 ± 0.79 (11.86- 13.42); width of abdomen 6.77 ± 0.32 (6.46-7.10); head length 2.18 ± 0.11 (2.06-2.28); head width 2.63 ± 0.06 (2.56-2.68); eye length 0,60 ± 0.03 (0.57-0.63); eye width 0.78 ± 0.03 (0.75- 0.82); interocellar distance 0.70 ± 0.01 (0.69-0.71); interocular distance 1.12 ± 0.05 (1.07-1.15); pronotum length 3.47 ± 0.18 (3.27-3.59); pronotum width 6.01 ± 0.18 (5.82-6.17); length of pronotal lobe 0.41 ± 0.02 (0.40-0.44); pronotal lobe width 0.85 ± 0.02 (0.80-0.84); scutellum length 4.45 ± 0.30 (4.12-4.70); scutellum width 3.65 ± 0.08 (3.55-3.70); length of antennomers: I 0.97 ± 0.04 (0.92-1.00); II 1.12 ± 0.08 (1.07-1.21); III 1.42 ± 0.07 (1.35-1.50); IV 1.38 ± 0.20 (1.2-1.56); V 1.78 ± 0.00 (1.78- 1.78); length of labial segments: I 1.35 ± 0.70 (1.28-1.42); II 2.43 ± 0.14 (2.34-2.60); III 1.97 ± 0.14 (1.85-2.13); IV 1.66 ± 0.05 (1.63-1.72).

Material examined. BRAZIL, Amazonas: 3 females, São Miguel da Cachoeira ( Cachoeira do Tucano – Pico da Neblina ), X.2007, Nogueira & Candiani leg .; Pará: 2 males, Moju ( Fazenda Sococo ) [-2.11; -48.00], 01.XII.1995, P. Lins leg.; 1 male, Tucuruí ( Rio Tocantins ) [-3.7; -49.7], 20.VII.1984, W. França leg.

Distribution: Suriname, Brazil (Amazonas and Pará States).

Remarks. Lincus incisus was placed, along with eight other species ( Lincus convexus Rolston, 1983 , Lincus croupius Rolston, 1983 , Lincus fatigus Rolston, 1983 , Lincus operosus Rolston, 1983 , Lincus securiger Breddin, 1904 , Lincus sinuosus Rolston, 1983 , Lincus spathuliger Breddin 1908 and Lincus vandoesburgi Rolston, 1983 ), in the “hatchet-lobed” informal group of species ( ROLSTON 1983). This placement was justified in view of the anterior pronotal angles resembling a hatchet blade in Lincus incisus . Males of L. incisus share some genitalic characters with males of L. convexus , L. securiger , L. sinuosus and L. vandoesburgi , such as the presence of 1+1 median projections at posterolateral angles, ventrally directed; and an elongated phallus bearing apical projections. The ductus seminis distalis bent toward the projections of the vesica is also observed in L. vandoesburgi . Within the hatchet-lobed group, L. incisus and L. vandoesburgi share the pronotal margin posterior to the lobes expanded on each side into an obtuse projection. The incision between each lobe and the anterolateral margin of the pronotum is deepest in L. incisus , reaching half the width of an eye ( Fig. 10 ; ROLSTON 1983, Figs. 1, 8 ). Lincus incisus can also be distinguished from L. vandoesburgi by the more convex apical margin of the posterolateral angles of the pygophore, and by a more developed median projection ( Figs. 11-12 , mp; for L. vandoesbugi see ROLSTON 1983, Fig. 2 ). Among the other species in the hatchet-lobed group with known males, L. incisus differs from L. sinuosus by the median projection below the apical margin of the posterolateral angles of the pygophore ( Figs. 11-12 , mp; for L. sinuosus see ROLSTON 1983, Fig. 17); from L. convexus and L. securiger by the more developed median projection and the ventral opening of the pygophore broader and shallower ( Figs. 11-12 , mp, vr; for L. convexus and L. securiger see ROLSTON 1983, Figs. 23 and 26). Notwithstanding the placement of L. incisus within the “hatchet-lobed” group, it is noticeable that the shape of segment X, with an expanded and flattened apex, is also a feature of some species of the “bigeyed” group ( ROLSTON 1983), such as Lincus lethifer Dolling, 1984 , Lincus substyliger Rolston, 1983 and Lincus subuliger Breddin, 1908 . Lincus incisus is recorded for the first time in Brazil.

Figures

Figures 10-18. Male of Lincus incisus: (10) habitus in dorsal view; (11-12) pygophore: (11) dorsal view; (12) ventral view; (13-15) right paramere: (13) dorsal view; (14) ventral view; (15) lateral view; (16-18) phallus: (16) anterior view; (17) posterior view; (18) lateral view. (dp) Dorsal projections, (dr) dorsal rim, (ds) ductus seminis distalis, (lp) lateral projection, (mp) median projection, (pa) posterolateral angles, (ph) phallotheca, (t) tumescent area, (v) vesica, (pp) posterior projection, (vr) ventral rim, (X) segment X. Scale bars: 10- 12 = 1 mm, 13-18 = 0.5 mm.

Figures 1-9. Male of Lincus singularis: (1) habitus in dorsal view; (2-3) pygophore: (2) dorsal view; (3) ventral view; (4-6) left paramere: (4) dorsal view; (5) ventral view; (6) lateral view; (7-9) phallus: (7) anterior view; (8) posterior view; (9) lateral view. (dp) Dorsal projections, (dr) dorsal rim, (ds) ductus seminis distalis, (lp) lateral projection, (pa) posterolateral angles, (ph) phallotheca, (t) tumescent area, (v) vesica, (vr) ventral rim, (X) segment X. Scale bars: 1-3 = 1 mm, 4-9 = 0.5 mm.