Robackia parallela, Yan, Chuncai & Wang, Xinhua, 2006

Yan, Chuncai & Wang, Xinhua, 2006, Robackia Saether from China (Diptera: Chironomidae), Zootaxa 1361, pp. 53-59 : 54-55

Robackia parallela sp. n.

( Figs. 1–4 )

Type material

Holotype male, CHINA: Sichuan Province, Batang County, Zhubalong Town, 2500 m a.s.l., light trap, 11.vii.2001, R. Zhang (BDN no. 20234).

Etymology

From Latin parallelus, referring to the parallel-sided superior volsella.

Diagnostic characters

The species is similar to R. pilicauda in the shape of the hypopygium, but can be separated by having a much lower AR, tergite IX with rounded posterior margin, a parallel-sided superior volsella, and abdomen with dark brown marks.

Description

Male imago (n = 1). Total length 3.33 mm. Wing length 1.85 mm. Total length / wing length 1.80. Wing length / length of profemur 2.61.

Coloration. Thorax yellowish brown, with dark brown vittae, and mid preepisternum; median anepisternum dark brown; anterior 1/2 of postnotum blackish brown. Front legs dark brown; mid and hind legs yellowish brown with tarsi brown. Abdomen ( Fig. 1 ) yellowish brown, tergites VII–IX with longitudinal dark bands, tergites VII–IX and hypopygium dark brown.

Head. AR 1.30. Ultimate flagellomere 480 Μm long. Temporal setae 14, including 4 inner verticals, 5 outer verticals and 5 postorbitals. Clypeus with 13 setae. Tentorium 132 Μm long, 25 Μm wide. Palpomere lengths (in Μm): 30, 50, 128. 130. 175. Palp segment 5 / 3 1.37.

Thorax. Antepronotals absent, acrostichals 7, dorsocentrals 8, prealars 4. Scutellum with 7 setae.

Wing ( Fig. 2 ). VR 1.19, R with 3 setae, R1 bare, R4+5 with 2 median and 2 apical setae. Brachiolum with 3 setae. Squama with 5 setae.

Legs. Front tibia with 2 long subapical setae, 93 and 110 Μm long; spurs of mid tibia 25 and 27 Μm long, comb with 20 teeth, 10 Μm long; spurs of hind tibia 20 and 35 Μm long, comb with 40 teeth, 12 Μm long. Mid and hind legs without sensilla chaetica. Lengths (in Μm) and proportions of legs as in Table 1 .

Hypopygium ( Figs. 3–4 ). Tergite IX with 4 strong dorsal setae at base of anal point and 6 setae on ventral projection. Anal point bearing 12 weak setae. Laterosternite IX with 1 seta. Anal point nearly parallel-sided with rounded apex, 65 Μm long, 20 Μm wide at base, 8 Μm wide in the middle, 10 Μm wide at apex. Anal tergite with rounded posterior margin, tergite bands V-shaped. Phallapodeme 77 Μm long. Transverse sternapodeme 65 Μm long. Superior volsella digitiform, slightly curved, with 1 apical and 1 subapical seta. Inferior volsella covered with microtrichia. Gonocoxite 90 Μm long, with 5 strong ventromesal setae. Gonostylus 180 Μm long, slightly bent, with 12 setae along mesal margin. HR 2.26, HV 3.33.

Figures

FIGURES 1 – 4. Robackia parallela sp. n, male holotype. 1. Abdomen. 2. Wing. 3. Hypopygium, dorsal view. 4. Hypopygium, ventral view.

Tables

TABLE 1. Lengths (in µm) and proportion of legs of Robackia parallela sp. n., male holotype (n = 1).

fe	ti	ta1	ta2	ta3	ta4	ta5	LR
p1 710	500	820	480	340	260	140	1.64
p2 640	610	330	170	140	80	70	0.54
p3 750	790	510	270	200	120	90	0.65