Polypedilum (Pentapedilum) muscicola (Kieffer) Oyewo & Saether, 2008

Oyewo, Emmanuel Adeoye & Saether, Ole A., 2008, Revision of Polypedilum (Pentapedilum) Kieffer and Ainuyusurika Sasa et Shirasaki (Diptera: Chironomidae), Zootaxa 1953, pp. 1-145 : 79-81

Polypedilum (Pentapedilum) muscicola (Kieffer) comb. n.

( Fig. 25)

Pentapedilum muscicola Kieffer, 1924: 36 .

Not Polypedilum (Pentapedilum) tritum (Walker) ; Edwards (1929: 376).

Material examined. BELGIUM: Locality and date not stated, holotype male, M. Goetghebuer ( IRSN) .

Diagnostic characters. The species has numerous setae on the wing membrane, uniformly colored abdomen, foretibial scale with spur, base of superior volsella without microtrichia and projection almost straight as in P. (Pe.) intuber and P. (Pe.) botasaneanui, but differs from both by lacking seta on the projection of the superior volsella.

Male (n= 1)

Total length 3.42 mm. Wing length 2.08 mm. Total length / wing length 2.59. Wing length / length of profemur 1.64. Thorax, abdominal segments, femur, tibia and tarsi pale brown.

Head ( Fig. 25A). AR 1.80. Ultimate flagellomere 743 µm long. Temporal setae 14, including 6 inner verticals, 4 outer verticals, and 4 postorbitals. Clypeus with 24 setae. Tentorium ( Fig. 25B) 150 µm long, 7 µm wide at posterior tentorial pit. Stipes not measurable. Palpomere lengths (in µm): 49, 50, 162, 143, 245. Fifth palpomere / third palpomere 1.51. Third palpomere with 3 sensilla clavata.

Thorax ( Fig. 25C). Acrostichals 14, dorsocentrals 26, prealars 11. Scutellum with 16 setae.

Wing. Anal lobe moderately developed. VR 1.07. Brachiolum with 7 setae, R with 69, R 1 with 83, R 4+5 with 140, Sc with 63, RM with 4, M with 18, M 1+2 with 86, M 3+4 with 58, Cu with 52, Cu 1 with 19, PCu with 57, An with 55 setae. Cell m basal of RM with 42 macrotrichia. All other cells with more than 100 macrotrichia. Squama with 13 setae.

Legs. Scale on foretibia ( Fig. 25D) 62 µm long, with 12 µm long apical spur. Spurs on midtibia 57 µm long, on hind tibia 57 µm long. Comb on midtibia 19 µm long, combs on hind tibia ( Fig. 25E) 23 µm and 23 µm long. Width at apex of foretibia 55 µm, of midtibia 58 µm, of hind tibia 63 µm. Length and proportions of legs as in Table 30.

Hypopygium (uncleared). Tergite IX with 11 median setae, laterosternite IX with 2 setae. Anal point ( Fig. 25F) 43 µm long, 12 µm wide at base, tapering towards 10 µm wide globule-shaped apex. Transverse sternapodeme 60 µm long, phallapodeme 67 µm long. Gonocoxite 188 µm long. Superior volsella ( Fig. 25G, H)

81 µm long, base bare with 3 inner basal setae, projection without lateral seta. Inferior volsella ( Fig. 25I) 150 µm long, parallel-sided, with prominent apical seta. Gonostylus 171 µm long. HR 1.10, HV 2.00.

Remarks. The redescription of the holotype does not fit the description by Kieffer (1924: 36), especially concerning the superior volsella. The projection lacks a lateral seta and there are three inner setae as opposed to five. The superior volsella is similar to Polypedilum (Polypedilum) ephippium Freeman , but lacks microtrichia on the base. The species cannot be a synonym of Pentapedilum tritum since it lacks a lateral seta on the superior volsella and there are also differences in the number of setae on the wing, especially on veins R, R 1, R 4+5, Sc, RM, and M. The brachiolum bears 7 setae; in P. (Pe.) tritum the number never exceeds 4. Further, the shape of the superior volsella is different. The number of prealars and setae on the scutellum is higher than in P. (Pe.) tritum ; and the species is much larger than P. (Pe.) tritum .

Distribution. Known from Germany and Belgium.