Pseudosmittia subtrilobata (Freeman)

Ferrington Jr, Leonard C. & Saether, Ole A., 2011, A revision of the genera Pseudosmittia Edwards, 1932, Allocladius Kieffer, 1913, and Hydrosmittia gen. n. (Diptera: Chironomidae, Orthocladiinae) 2849, Zootaxa 2849 (1), pp. 1-314 : 262-264

Pseudosmittia subtrilobata (Freeman)

( Fig. 99 )

Smittia subtrilobata Freeman, 1956: 357 .

Pseudosmittia subtrilobata (Freeman) ; Lehman 1979: 45, Freeman & Cranston 1980: 186.

Material examined: D. R. CONGO: Katena, Luio , 1 male, 26.x.1957, det. P. Freeman ( BMNH) ; Kalengo , 2 males, 27.viii.1972, 9.i.1973, J. Lehmann ( ZSM) . TANZANIA: Tanga, West Usambara Mountains, Mazumbai , Malaise trap, 3 males, xi.1990, ZMBN's Tanzania Expedition ( ZMBN) .

Diagnostic characters: The species differs from P. trilobata in having 0–3, 2 setae on vein R 1, LR 1 0.45–0.46, LR 2 0.59–0.61 and LR 3 0.60–0.62, relatively shorter gonocoxite giving HR of 1.95–2.38 and more narrow and proportionately longer volsellae.

Male imago (n = 5–6, except when otherwise stated)

Total length 1.55–1.93, 1.73 mm. Wing length 0.97–1.18, 1.07 mm. Total length/wing length 1.53–1.71, 1.61. Wing length/length of profemur 3.06–3.38, 3.30. Coloration black.

Head ( Fig. 99 B ). AR 1.01–1.30, 1.17. Terminal flagellomere 325–405, 362 µm long. Temporal setae 5–9, 6, consisting of 2–4, 3 inner verticals, 3–4, 3 outer verticals and 0–2, 0 postorbitals. Clypeus with 8–11, 9 setae. Cibarial pump and stipes as in Fig. 99 D . Tentorium 94–105, 102 µm long, 18–25, 21 µm wide. Stipes 91–103, 93 µm long, 23–32, 29 µm wide. Palpomere lengths (in µm): 21–25, 23; 30–37, 34; 59–82, 69; 73–88, 81; 103–125, 113 (4). Third palpomere ( Fig. 99 C ) with 2–3 (3) sensilla clavata at apex.

Thorax. Antepronotal lobes slightly reduced medially, antepronotum with 1 (4) lateral setae. Dorsocentrals 9–13, 11; acrostichals 2; prealars 4. Scutellum with 4–6, 6 setae.

Wing ( Fig. 99 A ; Lehmann 1979, fig. 131). VR 1.40–1.49, 1.46. Anal lobe weak. Costal extension 11–30, 20 µm long. R 4+5 ending proximal to apex of M 3+4; Cu 1 distinctly sinuate. Brachiolum with 1 seta, R with 0–3, 2 setae, other veins bare.

Legs. Spur of front tibia 39–48, 41 µm long, spurs of middle tibia 16–21, 18 µm (4) and 14–17, 15 µm (4) long, of hind tibia 41–46, 43 µm and 16–21, 18 µm long. Width at apex of front tibia and middle tibiae each 18–25, 22 µm, of hind tibia 29–32, 31 µm. Comb of 11–12, 11 setae, shortest setae 18–23, 21 µm long, longest setae 32–41, 35 µm long. Lengths and proportions of legs as in Table 73.

Hypopygium ( Fig. 99 F ; Freeman 1956, fig. 13m; Lehmann 1979, fig. 130). Anal point absent; tergite IX with 4– 6, 5 setae; laterosternite IX with 2–3, 3 setae. Phallapodeme 69–81, 76 µm long; transverse sternapodeme 43–55, 47 µm (4) long, no oral projections. Virga ( Fig. 99 E ) 18–27, 22 µm long. Gonocoxite 98–123, 111 µm long; superior volsella 27–32, 30 µm long, median volsella 34–39, 37 µm long, with sharply pointed apical lamella; inferior volsella 14–23, 20 µm long. Gonostylus 48–55, 54 µm long; megaseta 5–8, 6 µm long. HR 1.95–2.38, 2.19; HV 3.18–3.51, 3.23.

Female, pupa and larva

Unknown.

Remarks

This species may be considered as a subspecies or even a form of P. trilobata . The differences in the mid leg ratio, however, seem to be significant when considered with respect to other differences among the two species. For instance, the hypopygium appears to be different in proportions, with a shorter gonocoxite and more narrow volsellae. However, some Palaearctic specimens of P. trilobata are highly variable and approach being intermediate in some of these characters.

Distribution

The species is only known from South Africa, Tanzania and D. R. Congo.

Figures

FIGURE 99. Pseudosmittia subtrilobata (Freeman), male. A—wing; B—head; C—third palpomere; D—cibarial pump and stipes; E—hypopygium, left dorsal aspect, right ventral aspect; F—virga.