Polypedilum (Pentapedilum) calvescens Freeman

Oyewo, Emmanuel Adeoye & Saether, Ole A., 2008, Revision of Polypedilum (Pentapedilum) Kieffer and Ainuyusurika Sasa et Shirasaki (Diptera: Chironomidae), Zootaxa 1953, pp. 1-145 : 42-45

Polypedilum (Pentapedilum) calvescens Freeman

( Figs 10D–G)

Polypedilum (Pentapedilum) calvescens Freeman, 1958: 300 .

Pentapedilum calvescens Freeman ; Freeman and Cranston (1980: 195). Material examined. SOUTH AFRICA: Cape Province, Berg River, French Hoek , holotype and paratype males, 25.iii.1955 & 20.iv.1955, K. M. F. Scott ( BMNH). GHANA: Northern Region, Sogo, White Volta River, 1 male, 11.ii.1993, light trap, NUFU project ( ZMBN). TANZANIA: Tanga Region, West Usambara Mts. , Mazumbai, Kaputu stream, 2 males, xi.90, ZMBN Tanzania expedition ( ZMBN) .

Diagnostic characters. The species can be separated from other species with less than 100 setae in each of cells m 1+2 and r 4+5 and foretibial scale without spur, by having base of superior volsella without microtrichia and with 2–3 inner setae on base, spatulate anal point and abdominal segments with broad dark bands.

Male (n = 5, unless otherwise stated)

Total length 2.88–3.06 (2) mm. Wing length 1.67–1.96 mm. Total length / wing length 1.57–1.83 (2). Wing length / length of profemur 1.96–3.18, 2.44 (4). Thorax pale brown on postnotum, anteprotum, preepisternum and scutum or completely brown. Abdominal segments with broad dark bands, femur, tibia and tarsi pale brown to brown.

Head ( Fig. 11A). AR 1.12–1.93 (3). Ultimate flagellomere 450–722 (3) µm long. Temporal setae 12 (3) including 2–4, 3 inner verticals, 3–5, 4 outer verticals and 2–4, 3 postorbitals. Clypeus with 10–17, 12 (4) setae. Tentorium 96–145, 129 (4) µm long; 4–7, 5 µm (4) wide at posterior tentorial pit. Stipes 91–160 (3) µm long. Palpomere length (in µm): 30–43, 38 (4); 30–47 (3); 96–109 (3); 100–121 (3); 156–213 (3). Fifth palpomere / third palpomere 1.63–1.95 (3). Third palpomere with 2–3 (3) sensilla clavata.

Thorax ( Fig. 11B). Acrostichals 7–11, 9; dorsocentrals 12–24, 17; prealars 3–5, 4 (4). Scutellum with 6–9 (3) setae.

Wing ( Fig. 10G). Anal lobe well developed, slightly lobed. VR 1.14–1.22, 1.18. Brachiolum with 1 seta; R with 20–28, 23; R 1 with 14–25, 19; R 4+5 with 27–52, 39 setae. Sc 0–3, 1; RM 0–1; M with 0–3, 1; M 1+2 with 31–57, 36; M 3+4 with 0–27, 13; Cu 0–5, 1; Cu 1 0–19, 4; PCu bare, An 0–1. Cell r 4+5 with 46–76, 62 macrotrichia; m 1+2 with 25–51, 42; m 3+4 with about 3–36, 20 setae; cell m basal of RM bare; an plus cu 0–21, 4. Squama with 5–12, 8 setae.

Legs. Scale on foretibia ( Fig. 10D) 16–60, 34 µm long, triangular, without apical spur. Spurs on midtibia 38–61, 51 µm long; on hind tibia 49–70, 58 µm long. Comb on midtibia ( Fig. 10E) 12–25, 18 µm long; combs on hind tibia ( Fig. 10F) 15–25, 21 µm and 7–21, 16 µm long. Width at apex of foretibia 35–52, 45 µm; of midtibia 33–55, 47 µm; of hind tibia 48–61, 55 µm. Length and proportions of legs as in Table 8.

Hypopygium ( Figs 11C–E). Tergite IX with 8–11 (2) median seta, laterosternite IX with 2–3 (3) seta. Anal point 50–53 (2) µm long, 9–10 (2) µm wide at base, gradually tapering to nearly parallel-sided towards spatulate, 6 (2) µm wide apex. Transverse sternapodeme 23–29 (2) µm long; phallapodeme 44–88 (2) µm long. Gonocoxite 110–179 (2) µm long. Superior volsella ( Fig. 11E) 56–63 (2) µm long, projection slightly curved, with 1 dorsolateral seta, base without microtrichia, with 2–3 inner setae. Inferior volsella ( Fig. 11D, E) 84–

107 (3) µm long; parallel-sided with 1 prominent apical seta. Gonostylus 105–145 (3) µm long. HR 1.04–1.23 (2); HV 2.06–2.91 (2).

Remarks. Wing vein M 3+ 4 in the holotype is bare; Cu to An are bare in all specimens examined except that the paratype has setae on Cu, Cu 1, and An. Wing cell an plus cu is bare except for in the paratype which has 21 macrotrichia. Foretibial scale may be pointed in the holotype.

Distribution. Known from South Africa, Zimbabwe, Tanzania, and Ghana ( Freeman & Cranston 1980: 195).