Polypedilum (Pentapedilum) elongatus Tokunaga

Oyewo, Emmanuel Adeoye & Saether, Ole A., 2008, Revision of Polypedilum (Pentapedilum) Kieffer and Ainuyusurika Sasa et Shirasaki (Diptera: Chironomidae), Zootaxa 1953, pp. 1-145 : 53-55

Polypedilum (Pentapedilum) elongatus Tokunaga

( Fig. 15A)

Polypedilum (Pentapedilum) elongatus Tokunaga, 1964: 600 .

Material examined. FEDERATED STATES OF MICRONESIA: Truk, 2 paratype males, 24.v.1946; H. K. Townes ( BM) ; Truk, Meon Island, Mt. Teroken , 80 m a.s.l., paratype male, 29.xii.1952, light trap, J. L. Gressitt (BM-13) ; Truk, Tol Island, Mt. Unibot , 32 m a.s.l., paratype male, 3.i.1953, light trap, J. L. Gressitt ( KYU) .

Diagnostic characters. Among species with strongly haired wing membrane, uniformly colored abdomen, no spur on foretibial scale, and base of superior volsella without microtrichia, P. (Pe.) elongatus can be distinguished by lacking inner setae on the base of the superior volsella, having wing veins RM and M bare, and 21–24 prealars.

Male (n= 4, unless otherwise stated)

Wing length 908–978 (3) ìm. Wing length / length of profemur 2.19–2.60 (3). Thorax brown on postnotum, antepronotum, preepisternum and scutum. Abdomen brown; femur, tibia and tarsi brown.

Head. AR 0.70–0.97, 0.84. Ultimate flagellomere 236–276, 254 µm long. Temporal setae 10 (1). Clypeus with 13 (1) setae. Palpomere lengths (in µm): 16–26 (2), 21 (2), 45–47 (2), 70–72 (2), 106 (1). Fifth palpomere / third palpomere 2.28 (1). Third palpomere with 2–3 (2) sensilla clavata.

Thorax. Acrostichals 8–12 (2), dorsocentrals 9–12 (2), prealars 21–24 (2). Scutellum with 23–30 (3) setae.

Wing. Anal lobe reduced. VR 1.29–1.33 (3). Brachiolum with 1 (1) seta, Sc with 12 (1) setae, R with 16– 18 (2), R 1 with 7–9 (2), R 4+5 with 23 (2), M with 0 (1), RM with 0 (1), M 1+2 with 24 (1)setae; M 3+4, Cu, Cu 1, PCu and An seem to lack setae. Cells m basal of RM, r 4+5, m 1+2, m 3+4, and cu plus an each covered with few macrotrichia. Squama damaged, with 3–5 setae according to Tokunaga (1964).

Legs. Scale on foretibia 12–17 (3) µm long, rounded, without apical spur. Spurs on midtibia 23–28 (2) µm long, on hind tibia 21–24 (2) µm long. Comb on midtibia 9–12 (2) µm long, combs on hind tibia 12–14 (2) µm and 9–12 (2) µm long. Width at apex of foretibia 24–26 (3) µm, of midtibia 27–33 (3) µm, of hind tibia 23–30 (3) µm. Length and proportions of legs as in Table 15.

Hypopygium. Tergite IX with 6 (1) median setae, laterosternite IX with 1–3, 2 setae. Anal point 41–50, 44 µm long, 8–12, 10 µm wide at base, nearly parallel-sided towards 2–4, 3 µm wide apex. Transverse sternapodeme and phallapodeme not clear on slides. Gonocoxite 82–97, 89 µm long. Superior volsella ( Fig. 15A) 31– 44, 40 µm long; broad based with microtrichia and no inner seta, projection very slender apically with 1 dorsolateral seta. Inferior volsella 61–71, 68 µm long; parallel-sided, with 1 prominent apical seta. Gonostylus 104–120, 113 µm long. HR 0.78–0.81, 0.79.

Distribution. Known from the Federated States of Micronesia ( Caroline Islands, Truk).