Systropus chinensis Bezzi 1905

Systropus chinensis Bezzi, 1905

(Figs. 24–31, 43–45)

Systropus chinensis Bezzi, 1905: 275. Type locality: China (Beijing).

Systropus oestrus Du & Yang C., 2009: 318. Type locality: China (Beijing). Syn. nov.

Diagnosis. Antenna black. Mesoscutum with two pale yellow lateral spots. Metasternum entirely black. Hind coxa black; trochanter brown; femur brownish yellow; tibia black except apical 1/5 yellow; tarsus brown to dark brown except basal part of first tarsomere yellow.

Description. Male. Body length 21–23 mm, wing length 11–12 mm.

Head black except lower frons, face and gena yellowish, ocellar tubercle red brown. Setulae on head yellowish, except lower frons, face and gena with short silvery white pile; upper occiput with black setulae along eye margin. Antenna black; scape and pedicel with short black setulae; first flagellomere flat and bare. Antennal ratio 2.5: 1: 1.5. Proboscis black except basal ventral portion mostly yellowish brown, bare; palpus brown with very short pale setulae.

Thorax black with yellow spots. Setulae on thorax pale and dark brown; yellow areas with pale setulae. Propleuron pale yellow. Postpronotal lobe pale yellow. Mesoscutum with two pale yellow lateral spots, midlateral spot absent. Anterolateral spot transverse and nearly parallel-sided, posterolateral spot triangular. Postalar callus yellow. Scutellum black, with pale pile on posterior border. Anepimeron with anterior portion dark brown and posterior portion gray, with pale setulae on posterior margin. Metasternum black.

Fore leg yellow except second to fifth tarsomeres yellowish brown; 3 dark brown dorsal setulae present at tip of fifth tarsomere. Mid leg yellow except femur yellowish brown. Hind coxa black; trochanter brown; femur brownish yellow; tibia black except apical 1/5 yellow; tarsus brown to dark brown except basal part of first tarsomere yellow. Claws shining black, pulvilli yellow. Setulae on legs mostly short and recumbent, those on black area black while those on yellow area yellowish brown. Hind tibia with three rows of black spinelike setae (7 ad, 5 av and 3 pv); mid and hind tarsi with black spine-like ventral setae.

Wing with pale smoky infuscation; veins brownish. Halter stem yellowish brown; knob brown dorsally.

Abdomen yellow except tergite 1 black with anterior margin wider than scutellum; tergites 2–5 with dark brown mid-longitudinal stripes; tergite 6 to hypopygium dark brown. Petiolus formed from segments 2–4 and anterior part of segment 5; segments 5–8 inflated, ovate. Setulae on abdomen very short, recumbent and black, except tergite 1 with pale postero-lateral setulae, tergites 2–5 with pale setulae on yellow portions.

Male genitalia (Figs. 24–29). Epandrium (Figs. 24–25) as long as wide, rectangular; surstylus blackened at dorsal apical portion and pointed; cercus in posterior view rather elliptical and with large and wide blackened tubercle located along inner margin of cercus. Sternite 10 (Fig. 25) U-shaped and wide. Gonocoxite (Figs. 26–27) longer than wide, narrower posteriorly, with large V-shaped basal incision; gonostylus (Figs. 26–27) wider at base, then narrowed, bluntly pointed at tip, apical part blackened. Midposterior part of dorsal band protruded and blackened at apex; median epiphallic lobe tapering apically; each lateral epiphallic lobe triangular, pointed apically, longer than median epiphallic lobe, blackened at apex.

Female. Body length 20–23 mm, wing length 13–15 mm. Similar to male, apical black part of sternite 8 tapering apically, large and equilaterally triangular (Figs. 30–31).

Material examined. 1 male, 1 female, CHINA: Beijing, Wangershan (40°01’ N; 116° 15’ E), 16. VIII. 1986, Jinping Du. 2 males, 2 females, CHINA: Shandong, Qingdao, Laoshan (36°03’ N; 120° 19’ E), 17. VII. 1986, Qiang Li. 1 male, CHINA: Shandong, Qingdao, Laoshan (36°03’ N; 120° 19’ E), 26. VII. 1986, Qiang Li.

Distribution. China (Beijing, Shandong).

Remarks. Systropus oestrus was established by Du and Yang (2009) according to one male and one female specimens. After examination and comparison of the type series of S. oestrus and S. chinensis, no distinct differences from S. chinensis were found. Consequently, S. oestrus is undoubtedly a new synonym of S. chinensis.