Sirthenea (Sirthenea) nigronitens ( Miller, 1958 )

Chłond, Dominik, 2018, A taxonomic revision of the genus Sirthenea (Hemiptera: Heteroptera: Reduviidae) of the Old World, Zootaxa 4520 (1), pp. 1-85 : 51-54

Sirthenea (Sirthenea) nigronitens ( Miller, 1958)

( Figs. 99–102, 155 , 177 , 204 , Map 9).

Sirtheneana nigronitens Miller, 1958: 72 . Holotype (♀): Rattan Camp : New Guinea: Indonesia; RMNH.

Sirthenea nigronitens: Willemse (1985: 25) .

Sirthenea nigronitens: Chłond (2008a: 385) .

Type material examined: Holotype, ♀: Neth. Ind.–American / New Guinea Exped. / Rattan Camp / 1500m / 04.ii. 1939 L.J.Toxopeus; Type; Sirtheneana / nigronitens / sub.gen.n. sp.n. (holotype) / N.C.E.Miller det. 1956. ( RMNH).

MAP 9. Distribution of Sirthenea nigronitens ( Miller, 1958) .

Diagnosis. This species can be easily distinguished from other representatives from the Oriental Region by the large, dark body, corrugated dorsal surface of antennifers, deep transversal furrow of the head, ridges of proepisternum and proepimeron connected in entire length, and spiracles III–IV placed close to ventral connexival suture. The straight Cu vein is a unique character of this species among other species of Sirthenea .

Redescription. Color: Body dark brown ( Figs. 99, 204 ) with paler clypeus, postocular part of head, basal part of costal vein, coxae (except darker basal part and half of ventral surface), apical part of femur and apical part of tibia. Setae pale (except brown setae on lateral parts of head). Margins of ocelli dark. Intercalar segments paler than other antennal segments. Scutellum darker than pronotum. Pronotum, meso- and metathoracic sterna with black spots. Hemelytron with darker clavus (except basal part) and small, black setae in costal margin. Legs covered by brown setae. Femur brown with pale apical part.

Structure: Body large and slender ( Fig. 99). Head, pronotum, scutellum, and costal margin shiny. Head with relatively long setae and a few visible trichobothrial setae on ventral and dorsal surface ( Fig. 155 ). Anteocular part of head 3 times longer than postocular part. Eyes and ocelli large. Eyes narrower than synthlipsis, with distinct Scurvature on posterior margin in lateral view. Dorsal surface of antennifers corrugated, transversal furrow of head deep, apodeme depression shallow. Scape not reaching apex of head, thickened distally with rather long, erect setae. Pedicel with dense, adherent, short setae; with several, regular arranged, erect setae and 2 long trichobothrial setae ( Fig. 177 ). Second visible labial segment not enlarged basally, reaching middle part of ocelli. Anterior pronotal lobe with distinctive sculpture and hairy (long setae), distinct sulci. Collar absent. Ridges of proepisternum and proepimeron connected in entire length. Apical margin of anterior pronotal lobe granulated. Posterior part of anterior pronotal lobe distinctly depressed medially. Transversal suture of pronotum with distinct, triangular curvature in middle. Posterior pronotal lobe with slightly depressed, longitudinal line in middle part. Metapleura with only one complete ridge. Scutellum with distinctly enlarged lateral margins and circular depressed area between them. Corium dull except shinning costal margin and basal part of hemelytron. Cu vein straight. Membrane distinctly wrinkled. Hemelytron surpassing apex of abdomen. Coxa and femur with rather long setae. Tibia and tarsus with dense adherent setae and spine-like setae (numerous on ventral side of middle tibia). Abdomen with spiracles III–IV placed close to ventral connexival suture. Ventral side of abdomen with various sized setae. Sternite of first visible abdominal segment as well as lateral parts of anterior and posterior margin of each sternite of abdomen with distinct sculpture.

Genitalia: Valvifer I subquadrangular ( Fig. 102 ), on outer side of posterior part with numerous, various sized setae and a few distinctly longer setae. On inner side small setae visible in posterior margin. Styloids with widely rounded ventral margins and dense, robust, long marginal setae ( Fig. 100 ). Distinct, curved depression visible on outer view. Basal part of valvula II with forked process convolute inwardly ( Fig. 101 ). Apical part with forked apex. Internal apex sharp, external apex flat.

Measurements (in mm): Body length: 22.1; maximum width of abdomen: 5.2; head length: 4.1; head width: 2.0; length of anteocular part: 2.4; length of postocular part: 0.8; length of synthlipsis: 0.9; interocellar distance: 0.5; length of antennal segments I:II:III:IV: 1.2: 2.2: missing: missing; length of visible labial segments I:II:III: 1.1: 3.3: 1.7; maximum length of anterior pronotal lobe: 2.9; maximum length of posterior pronotal lobe: 1.6; maximum width of anterior pronotal lobe: 3.6; maximum width of posterior pronotal lobe: 4.1; length of scutellum: 1.6; length of hemelytron: 14.3.

Male: Unknown.

Distribution: Indonesia (New Guinea) (Map 9).

Comments: This species was described based on a single specimen (the holotype) and it was placed into a genus of its own, Sirtheneana ( Miller, 1958) . The main morphological character differentiating this species from the other congeners is the very strongly elongated head which is shorter than length of pronotum (in Miller’s description these parts have same length). No morphological characters were found to justify a generic level differentiation of Sirtheneana and Sirthenea .

Figures

FIGURES 153–155. Head in lateral view: 153—Sirthenea picescens Reuter, 1887; 154—S. kali sp. nov.; 155—S. nigronitens (Miller, 1958).

FIGURES 169–182. Trichobothrial setae on pedicel: 169—Sirthenea africana Distant, 1903; 170—S. flaviceps (Signoret, 1860); 171—S. picescens Reuter, 1887; 172—S. rodhaini Schouteden, 1913; 173—S. caiana Chłond, 2008; 174—S. dimidiata Horváth, 1911; 175—S. flavipes (Stål, 1855); 176—S. kali sp. nov.; 177—S. nigronitens (Miller, 1958); 178—S. nitida Chłond, 2008; 179—S. nigra Cai & Tomokuni, 2004; 180—S. setosa sp. nov.; 181—S. laevicollis Horváth, 1909; 182—S. obscura (Stål, 1866).

FIGURES 201–204. Color figures of habitus: 201—Sirthenea flavipes (Stål, 1855); 202—S. flavipes var. apicalis Horváth, 1909; 203—S. kali sp. nov.; 204—S. nigronitens (Miller, 1958).

FIGURES 100–102. Sirthenea nigronitens (Miller, 1958): 100—styloids, outer view; 101—gonapophysis of VIII segment, inner view; 102—gonocoxite of VIII segment, inner view.