Polididus dimorphopterus

Ishikawa, Tadashi, Sumiartha, Ketut & Okajima, Shûji, 2008, The second representative of the genus Polididus (Hemiptera: Heteroptera: Reduviidae) in Southeast Asia, with partial redescription of P. armatissimus, Zootaxa 1740, pp. 45-52 : 46-50

Polididus dimorphopterus Ishikawa et Okajima, sp. nov.

( Figs. 1–4 , 7–14 )

Diagnosis. Anterior lobe of head dorsally with 3 pairs of long setiferous spines, 1 pair of short setiferous spines and 1 median long setiferous spine ( Fig. 7 ); posterior lobe of head with 2 pairs of long setiferous spines, 2 pairs of medium-sized setiferous spines and several short setiferous spines ( Fig. 7 ); pronotum dark brown to blackish, with a pair of brownish yellow longitudinal stripes on posterior lobe ( Figs. 1, 3 ); humeral setiferous spines simple; setiferous spines on pronotal humeri, scutellum and laterotergites IV to VII blackish in basal half and brownish yellow in apical half; femur of each leg blackish in apical fifth ( Figs. 10, 11 ); femora of mid and hind legs armed with a pair of dorsoapical setiferous spines, and dorsally with 2 rows of about 2 to 4 setiferous spines and several setiferous tubercles; tibiae of mid and hind legs lacking setiferous spine; metatibia with blackish narrow annulation subbasally ( Fig. 11 ); valvifer I nearly straight along posterior margin and rounded at apical angle ( Figs. 12, 13 ); and styloides sclerotized as in Fig. 14 . Body about 8.8 mm long.

Description. Macropterous female (holotype). Body ( Figs. 1, 2 ) mostly brownish yellow, setiferous tubercles often reddish. Head blackish dorsally and laterally and brownish yellow ventrally; dorsum with a pair of lateral longitudinal stripes and 1 median longitudinal stripe brownish yellow. Antennal segments I and II brownish yellow, darkened at both ends of each segment; segments III and IV brownish. Labium pale brownish yellow, with visible segment III brownish. Pronotum ( Fig. 1 ) dark brown to blackish, with a pair of brownish yellow longitudinal stripes on anterior and posterior lobes; humeral spine blackish in basal half and brownish yellow in apical half; other long spines on pronotum brownish yellow. Scutellum blackish, with narrow longitudinal stripe along meson brownish yellow; scutellar spine and a pair of spines on disc blackish in basal half and brownish yellow in apical half. Thoracic pleura blackish on lower half. Legs brownish yellow; femur of each leg blackish in apical fifth ( Figs. 1, 2 , 10, 11 ); tibia of each leg blackish at base and apex ( Figs. 10, 11 ); metatibia with blackish narrow annulation subbasally ( Fig. 11 ); tarsomere III dark at apex. Hemelytra pale brownish yellow and transparent, with veins pale brown to brown. Abdomen ventrolaterally with a pair of broad, longitudinal blackish stripes ( Fig. 2 ) and with a pair of narrow longitudinal blackish stripes along ventral midline of segments III to VII; tergites II to VI with a pair of broad, longitudinal blackish stripes; tergites VI and VII blackish medially; laterotergites IV to VII blackish in posterior half of marginal area, with long setiferous spine on posterior corner blackish in basal half and more anterior setiferous spine blackish ( Figs. 1 , 8 ). Pubescence on body and legs whitish.

Head ( Fig. 7 ) 1.6 times as long as width across eyes, about 0.8 times as long as pronotum, ventrally with 3 medium-sized setiferous spines on each side; anterior lobe dorsally with 3 pairs of long setiferous spines, 1 pair of short setiferous spines and 1 median long setiferous spine ( Fig. 7 ); posterior lobe dorsally with 2 pairs of long setiferous spines, 2 pairs of medium-sized setiferous spines and several short setiferous spines ( Fig. 7 ); anteocular area 0.7 times as long as postocular area; clypeus lacking projection. Eyes about 0.3 times as wide as synthlipsis in dorsal view. Antennal segment I covered with setiferous tubercles, and with short decumbent setae in basal half; longest setae about 3 times as long as width of segment I; segment II sparsely covered with setiferous tubercles, and densely with short suberect setae in apical fifth; segments III and IV covered with short decumbent setae; approximate proportion of segments I to IV 7.2: 3.5: 1: 2.3. Labium ( Fig. 7 ) sparsely covered with erect setae; visible segment I armed with a pair of setiferous tubercles in middle; approximate proportion of visible segments I to III 6: 3: 2.

Pronotum 0.9 times as long as humeral width, with medium-sized setiferous spine on each anterolateral angle; anterior lobe about 0.7 times as long as posterior lobe, deeply sulcate in posterior half along midline, medially armed with 2 pairs of long setiferous spines; spines of posterior pair seven-tenths as long as those of anterior pair; posterior lobe armed with a pair of short setiferous spines anteriorly and a pair of long setiferous spines near posterior margin, and laterally with long setiferous spine at anterior fifth length of posterior lobe (but spine lacking from left side); humeral setiferous spine simple, about one-fourth as long as humeral width, as long as long setiferous spine near pronotal posterior margin. Apical scutellar spine about 1.4 times as long as median paired scutellar spines. Hemelytron slightly exceeding apex of abdomen; corium covered with decumbent pubescence, basally with setiferous tubercles along costal margin. Fore leg armed with short to long setiferous spines and setiferous tubercles on femur and tibia; profemur with a pair of setiferous spines dorsoapically; anterior dorsoapical spine longer than posterior one. Mid leg armed with short to medium-sized setiferous spines and setiferous tubercles on femur, furnished with only setiferous tubercles on tibia; mesofemur dorsally with 2 rows of setiferous projections, and with a pair of dorsoapical setiferous spines; anterior row composed of 2 or 3 setiferous spines and several setiferous tubercles and posterior row of about 4 setiferous spines and several setiferous tubercles (excluding dorsoapical setiferous spines). Hind leg armed with short to medium-sized setiferous spines and setiferous tubercles on femur, furnished with only setiferous tubercles on tibia; metafemur armed with a pair of dorsoapical setiferous spines, dorsally with 2 rows of about 4 setiferous spines and several setiferous tubercles for each row (excluding dorsoapical setiferous spines).

Abdomen ( Fig. 1 ) elongate elliptical, 2.1 times as long as width, covered with short to long setae and setiferous tubercles intermixed with short, decumbent pubescence. Laterotergite II ( Fig. 8 ) with 2 setiferous spines and laterotergites III to VII with 3 or 4 spines marginally; setiferous spine on each posterior corner of laterotergites II to VII about twice as long as other marginal setiferous spines. Tergite VIII ( Fig. 9 ) with 4 medium-sized setiferous spines and 2 short setiferous spines along posterior margin.

Genitalia (paratype). Valvifer I ( Figs. 12, 13 ) weakly oblique along posterior margin, rounded at apical angle, covered with dense, short setae and a few long setae in apical part ( Fig. 13 ); valvula I ( Figs. 12, 13 ) narrow, rounded apically, densely covered with short setae in apical part ( Fig. 13 ). Styloides ( Fig. 14 ) rounded apically, laterally sclerotized as in Fig. 14 , densely covered with short, stout setae along apical margin, and with a pair of long setae apically.

Brachypterous female (paratypes). Almost the same as macropterous form. Pronotum ( Figs. 3, 4 ) relatively narrower than that of macropterous from, as long as humeral width; anterior lobe as long as or a little shorter than posterior lobe; posterior lobe depressed discally. Hemelytron ( Fig. 3 ) small, pad-like, lacking membrane, reaching at most middle of abdominal tergite III. Abdominal tergites II to VII medially armed with 2 pairs of setiferous spines; setiferous spines of anterior pair shorter than those of posterior pair.

Male. Unknown.

Measurements (mm; macropterous form (n=2) / brachypterous form (n=2); holotype in italic). Body length 8.63– 9.10 /8.73–8.75. Head length 1.48– 1.56 /1.52–1.57, width across eyes 0.96– 0.97 /0.95–0.97; synthlipsis 0.59- 0.60 /0.58-0.59; length of anteocular area 0.48– 0.49 /0.46–0.51, of postocular area 0.67– 0.70 /0.64– 0.68; antenna length 6.73– 7.12 /6.94–7.24, lengths of antennal segments I: 3.38– 3.6 8/3.62–3.68, II: 1.67– 1.77 / 1.69–1.84, III: 0.49– 0.51 /0.46–0.51, and IV: 1.16– 1.19/1.17–1.21; labium length 2.07– 2.17 /2.08–2.10, lengths of visible labial segments I: 1.11– 1.12 /1.10–1.12, II: 0.61– 0.63 /0.63–0.64, and III: 0.35– 0.40 /0.34– 0.35. Length of pronotum 1.84– 1.87 /1.60–1.67, width across humeri 2.04– 2.08/1.61–1.62; length of anterior pronotal lobe 0.74– 0.75/0.75–0.77, of posterior pronotal lobe 1.02– 1.10 /0.78–0.86. Hemelytron length 6.00– 6.17 /1.05–1.37. Lengths of foreleg femur: 3.22– 3.32 /3.32–3.48, tibia: 3.10– 3.15 /3.07–3.12, and tarsus: 0.55– 0.56 /0.50–0.56; of mid leg femur: 2.58– 2.65 /2.69–2.74, tibia: 2.57– 2.62 /2.57–2.62, and tarsus: 0.63– 0.67 / 0.63–0.64; of hind leg femur: 3.44– 3.68 /3.62–3.78, tibia: 4.04– 4.18 /4.04–4.06, and tarsus: 0.67– 0.68 /0.67– 0.70. Abdomen length 4.50– 5.25 /5.00–5.13.

Type series. Holotype: macropterous Ψ ( Figs. 1, 2 , 7–11 ), “[ INDONESIA] Wolobobo, Ngada, Flores, 8°50’16”S, 120°59’13”E, 1440m, alt., 28.viii.2006, T. Ishikawa et al.” (TUA). Paratypes: 1 macropterous Ψ ( Figs. 12–14 ), 2 brachypterous Ψ (one shown in Figs. 3, 4 ), same data as holotype (1 brachypterous Ψ in TUA﹐ ΟɭhɵrS in UU).

Distribution. Indonesia ( Flores).

Etymology. From the Latin, dimorphopterus , referring to the wing dimorphism, macroptera and brachyptera, which appears in this new species; an adjective.

Remarks. Polididus dimorphopterus sp. nov. is the first representative showing wing dimorphism in the genus Polididus . Wing dimorphism or polymorphism appears to be very rare in the subfamily Harpactorinae while some congeners of the genus Coranus Curtis, 1833 , as far as known to us, exceptionally show the dimorphism. The present discovery of the dimorphism in Polididus is rather remarkable.

This new species is similar to Polididus australis Distant, 1903 , described from northwestern Australia and P. armatissimus Stål, 1859 occurring widely in Southeast Asia, but is separable from the latter two by the pronotum dark brown to blackish with a pair of brownish yellow longitudinal stripes ( Fig. 1 ) (in P. australis and P. armatissimus , brown in the anterior lobe and yellowish brown in the posterior lobe without stripes, Fig. 5 ), setiferous spines on the pronotal humeri, scutellum and laterotergites IV to VII blackish in the basal half and brownish yellow in the apical half ( Figs. 1, 3 , 8 ) (vs. yellow to brownish yellow with the brownish or reddish base, Fig. 5 ), the femur of each leg blackish in the apical fifth ( Figs. 1–4 , 10, 11 ) (vs. reddish to blackish in the apical half in the pro- and mesofemora and in the apical third in the metafemur, Figs. 5, 6 ), and the valvifer I not projected posteriad at the apex ( Figs. 12, 13 ) (vs. roundly projected posteriad at the apex, Figs. 20, 21 ).

Habitat. This new species was collected in dry vegetation such as silver and blady grasses in Flores. All the specimens examined were found on the ground covered with vegetation.

Figures

FIGURES 1 – 6. Polididus dimorphopterus sp. nov. (1 – 4) and P. armatissimus (5 – 6), 1 – 2, macropterous female (holotype), dorsal (1) and lateral (2) views; 3 – 4, brachypterous female, dorsal (3) and lateral (4) views; 5 – 6 male, dorsal (5) and lateral (6) views. Scale bars: 2.0 mm.

FIGURES 7 – 14. Polididus dimorphopterus sp. nov. (pubescence omitted; setae omitted for Fig. 12), 7, head, lateral view; 8, abdominal segments II to VII, left ventrolateral view; 9, apical part of abdomen, ventral view; 10 – 11, apical part of femur and basal part of tibia, mid leg (10) and hind leg (11), lateral view; 12 right valvifer I and valvula I, ventral view; 13, apical part of valvifer I and valvula I, ventral view; 14, styloides, dorsal view. Scale bars: 0.5 mm for Figs. 7 – 12; 0.2 mm for Figs. 13 – 14. Abbreviations: m, median long setiferous spine; pl, paired long setiferous spines; pm, paired medium-sized setiferous spines; ps, paired short setiferous spines; s 2, segment II; s 3, segment III; s 4, segment IV; s 5, segment V; s 6, segment VI; s 7, segment VII; s 8, segment VIII; vf 1, valvifer I; vv 1, valvula I.

FIGURES 15 – 22. Polididus armatissimus (setae omitted for Figs. 15, 16, 20), 15, pygophore, lateral view; 16, apical part of pygophore, dorsal view; 17, left paramere, lateral view; 18 – 19, phallus (endosoma retracted), lateral view (18) and dorsal view (19), phallobase inclined basad and ventrad for 19; 20, right valvifer I and valvula I, ventral view; 21, apical part of valvifer I and valvula I, ventral view; 22, styloides, dorsal view. Scale bars: 0.5 mm for Figs. 15, 16, 18 – 20; 0.2 mm for 17, 21, 22. Abbreviations: rs, rod-like sclerite; st, struts; tsp, triangular sclerotized projection; vf 1, valvifer I; vsl, ventral sclerotized lobe; vv 1, valvula I.