Orthocladius (Orthocladius) manitobensis Saether, 1969

Kong, Fanqing, A. Saether, Ole & Wang, Xinhua, 2012, A review of the subgenera Euorthocladius and Orthocladius s. str. from China (Diptera: Chironomidae), Zootaxa 3537, pp. 76-88 : 82-83

Orthocladius (Orthocladius) manitobensis Saether

( Figs 10–13)

Orthocladius (Orthocladius) manitobensis Saether, 1969: 69 ; Soponis 1977: 68.

Material examined. CHINA: Zhejiang Province, Tianmushan Natural Reserve Area , 2 males, 12.xi.1998, light trap, H. Zhou .

Diagnostic characters. The species can be separated from other members of the subgenus by having small triangular superior volsella, virga present, inferior volsella with dorsal part short and broad, and crista dorsalis long and low.

Description. Male (n = 2).

Total length 3.25–3.38 mm. Wing length 2.00– 2.05 mm. Total length / wing length 1.63–1.67. Wing length / length of profemur 2.33–2.56.

Coloration. Head and thorax dark brown. Antenna, legs and abdomen yellowish brown.

Head. AR 1.36–1.72. Ultimate flagellomere 610–670 µm long. Temporal setae 8–10, including 2–4 inner verticals, 3 outer verticals and 3 postorbitals. Clypeus with 7–9 setae. Cibarial pump, tentorium and stipes as in Fig. 10. Tentorium 143–167 µm long, 35–41 µm wide. Stipes 168–181 µm long, 65–73 µm wide. Palpomere lengths (in m): 30–35, 48–70, 97–125, 92–112, 165–175. Length ratio of palpomeres 5/3 1.40–1.70.

Wing ( Fig. 11). Anal lobe well developed. VR 1.05–1.08. Costal extension 20–30 µm long. R with 8–9 setae, other veins bare. Squama with 11–23 setae.

Thorax. Antepronotum with 4–7 setae. Dorsocentrals 10–13, acrostichals 6–10, prealars 3–6. Scutellum with 10–11 setae.

Legs. Spur of fore tibia 45–61 µm long, spurs of mid tibia 22–23 µm and 18–22 µm long; of hind tibia 48–50 µm and 19–23 µm long. Comb of 8–10 setae, shortest seta 22–29 µm, longest seta 37–46 µm. Width at apex of fore tibia 35–48 µm, of mid tibia 32–44 µm, of hind tibia 40 µm. Pseudospurs present on ta 1 and ta 2 of mid and hind leg, 20–24 µm long. Lengths (in µm) and proportions of legs in Table 4.

Hypopygium ( Figs. 12, 13). Tergite IX including anal point with 13–17 setae. Laterosternite IX with 6–10 setae. Anal point 52–66 µm long, 30–33 µm wide. Phallapodeme 80–83 µm long; transverse sternapodeme 108– 150 µm long, oral projections well developed. Gonocoxite 205 µm long, superior volsella small and triangular, inferior volsella with ventral part fully covered by dorsal part. Virga present, 35 µm long. Gonostylus ( Fig. 13) widest medially, 100–120 µm long; crista dorsalis long and low; megaseta 10 µm long. HR 1.71–2.05, HV 2.81– 3.25.

Remarks. The specimens from China have higher length ratio of palpomeres 5/3 and slightly longer anal point than illustrated for the Nearctic specimens. However, other characters are in accordance with the original description and according to Soponis (1977); the length of the anal point is variable.