Parorthocladius unicentrus, Liu, Yuedan & Wang, Xinhua, 2005

Liu, Yuedan & Wang, Xinhua, 2005, (Diptera: Chironomidae: Orthocladiinae), Zootaxa 802, pp. 1-8 : 5-7

Parorthocladius unicentrus sp. nov. ( Figs. 5–6 )

Male imago (n = 5, except when otherwise stated).

Total length 2.40–3.34, 2.73 mm. Wing length 1.21–1.45, 1.31 mm. Total length/wing length 1.96–2.47, 2.04. Wing length/profemur length 1.85–4.70, 1.98.

Coloration: Head yellow brown with dark brown frontal vertex. Thorax yellow with darker vittae, median anepisternum II, postnotum, and preepisternum. Abdominal segments brown with pale posterior margins. Legs brown. Wings light brown.

Head: Terminal flagellomere 380–460, 410 m long. AR 1.19–1.39, 1.28. Temporal setae (n = 4) 3–4, 3; 1–2, 1 inner verticals, 1 outer vertical and 2 postorbitals. Clypeus with 6–10, 8 setae. Tentorium 138–163, 152 m long. Palpomere lengths (m): 31—39, 34; 35– 39, 38; 105–125, 115; 134–158, 145; 173–195, 181. Segment 3 larger than other segments.

Thorax: Antepronotum with 2–4, 3 lateral setae. Dorsocentrals 6–8, 7, prealars 2–3, 3. Scutellum with 3–4, 3 setae.

Wing ( Fig. 5 ): Anal lobe protruding. VR 1.14–1.20, 1.17. R2+3 ends 1/3 distance between R1 and R4+5. Costal extension 30–37, 34 m long. Brachiolum with 1–3, 2 setae; R with 1–6, 3 setae; remaining veins bare. Cu1 slightly curved, end slightly recurved. Squama with 13–19, 16 setae.

Legs (n = 4): Spur of front tibia 29–48, 44 m long, spurs of middle single, 30–40, 36 m long, of hind tibia single, 32–38, 35 m. Hind tibial comb with 10–11, 11 setae. Middle and

hind tibial spurs with denticles. Two pseudospurs on tarsi I–III of middle and hind legs ( Table 3 ).

Hypopygium ( Fig. 6 ): Anal point 63–93, 76 m long, 28–34, 30 m wide at base, truncated apically. Anal point length/width 2.41–2.68, 2.53, with 9–12, 11 lateral setae. Tergite IX broad and bare, with 14–16, 15 long setae; laterosternite IX with 2–5, 3 setae. Phallapodeme broad, 58–75, 65 m long; transverse sternapodeme 98–110, 106 m long; oral projection well developed. Gonocoxite 178–209, 190 m long. Gonostylus slightly arched, 68–73, 70 m long, with 3 stout setae on inner side. Inferior volsella double, dorsal part sclerotized with sharp triangular apex, with 3–6, 4 long dorsal setae, ventral part semicircular, with about 25 long setae. Megaseta 13–15, 14 long. HR 2.54–2.82, 2.71, HV 3.53–4.77, 3.83.

Female and immature stages: Unknown.

Holotype: Male, P. R. CHINA: Guizhou Province, Maolan Natural Conservation (25° 23 N, 108° 0 4 E), alt. 420 m, 29. VII 1995, light trap, W. Bu, slide no. 0 8894.

Paratypes: 3 males, data as for holotype; 1 male from Guangdong Province, Fengkai County, Heishiding Natural Conservation (23° 27 N, 111° 30 E), alt. 450 m, 20. IV 1988, light trap, X. Wang.

Etymology: From Latin, unus, single and centrum, spur, referring to the single spur on each of the middle and hind legs.

Distribution: The specimens were collected with a light trap in a subtropical mountain area in two oriental Chinese provinces.

Remark s: Among the recorded species of the genus, this new species is similar to P. toyamajekeus (Sasa) from Japan, but can be separated by its double­layered inferior volsella and double pseudospurs on tarsomere III of the middle and hind legs.

Figures

FIGURES 5 – 6: Parorthocladius unicentrus sp. nov.: 5, wing (Holotype) (scale = 0.5 mm); 6, hypopygium (Paratype No. 08920) (scale = 0.2 mm).

Tables

TABLE 3. P. unicentrus sp. nov. Lengths (m) and proportions of leg segments.

	fe	ti	ta1 ta2
P1	530–710, 660	600–660, 630	430–500, 460(3) 290–350, 310(3)
P2	590–670, 640	510–590, 550	210–290, 260 140–180, 160
P3	590–700, 660	620–710, 670	360–420, 380 210–250, 230