Polypedilum (Uresipedilum) simantokeleum Sasa, Suzuki et Sakai

Yamamoto, Nao & Yamamoto, Masaru, 2015, A revised subgeneric position for Polypedilum (Probolum) simantokeleum, with description of a new Uresipedilum species in Japan (Diptera: Chironomidae), Zootaxa 3999 (3), pp. 439-445 : 440

Polypedilum (Uresipedilum) simantokeleum Sasa, Suzuki et Sakai

( Figs. 1–6 )

Polypedilum (Uresipedilum) simantokeleum Sasa, Suzuki et Sakai, 1998: 59 . Polypedilum (Uresipedilum) simantokeleum: Saether et Oyewo (2008: 4) Polypedilum (Probolum) simantokeleum: Saether et al. (2010: 15)

Material examined. Holotype male [NSMT-I-Dip 5227 (No. 360:50)], JAPAN: Shikoku, Kochi Pref., Nakamura, 26. v. 1998, H. Suzuki.

Diagnostic characters. This species is distinguished from other members of the subgenus Uresipedilum by having large and wide superior volsellae and distally expanded inferior volsellae. Each superior volsella and inferior volsella are wider than gonostylus. This species is quite similar to Polypedilum (Uresipedilum) crassiglobum Zhang et Wang, 2004 in the shape of superior volsellae, but distinguished from the latter by having expanded inferior volsellae (while parallel-sided in P. crassiglobum ) and basal portions of the superior volsellae each with 2 inner setae (while 4–5 in P. crassiglobum )

Male (n= 1). Total length 3.64 mm. Wing 2.0 mm long, 0.6 mm wide; wing length/wing width 3.33. Total length/wing length 1.82. Wing length/profemur 2.30.

Coloration. Body entirely pale yellow including scutal vittae, scutellum and postnotum.

Head. Frontal tubercle absent. Vertex with 11 temporal setae. AR 1.87. Palpomere lengths (in Μm): 38, 40, 150, 140, 235; palpomeres with 1, 6, 19, 14, 8 setae, respectively. Clypeus with 12 setae.

Thorax. Lateral antepronotals absent. Dorsocentrals 14 including 2 humerals, uniserial; acrostichals 16, biserial; prealars 4, uniserial. Scutellum with 18 setae, biserial.

Wing ( Fig. 1 ). Without microtrichia and dark markings. Anal lobe moderately developed. VR 1.15. R2+3 nearly parallel to R1 and ended at basal 2/5 between apices of R1 and R4+5. R, R1 and R4+5 with 22, 21, 35 setae, respectively. Squama with 11 setae.

Legs ( Fig. 2 ). Scale of fore tibia triangular, with rounded apex. Fore, mid and hind coxae with 1, 7, 7 setae, respectively; fore, mid and hind trochanters with 11, 7, 6 marginal setae, respectively. Foretarsi both lost. Lengths (in µm) and proportions of legs as in Table. 1 .

*p1–3: front-, mid-, hind-legs. Fe: femur. Ti: tibia. ta1-5: tasomeres 1–5. LR: leg ratio. BV: combined length of femur, tibia and basitarsus divided by combined length of tarsomeres 2–5. SV: ratio of femur plus tibia to metatarsus.

Hypopygium ( Fig. 3–6 ). Tergum IX with cluster of 11 median setae. Anal point long, slender, parallel-sided, with rounded apex. Superior volsella ( Fig. 4 ) with basal portion well-developed, bearing 2 inner setae, nearly rectangular in shape, 50 Μm long, 48 Μm wide, wider than gonostylus (38 Μm wide); with a short beak-like projection (15 Μm) at posterior corner of inner margin, and with a long seta at posterolateral corner of outer margin. Inferior volsella ( Fig. 5–6 ) expanded distally (43 Μm wide), not beyond tip of anal point, with 24 recurved setae on apical 1/4 dorsally, apical one of which is much longer than the others, and with posteriorly extending very long seta originated on subapical portion of ventral side. Sternapodeme narrow. Gonocoxite with 4 –5 uniserially arranged setae on inner margin. Gonostylus long, slender, lunate, with one apical and 9 setae on inner margin. Distribution. Japan ( Kochi Prefecture).

Figures

FIGURES 1 – 6. Adult male of Polypedilum (Uresipedilum) simantokeleum. 1: wing; 2: scale of foretibia; 3: genitalia, dorsal view; 4: superior volsella, dorsal view; 5 inferior volsella, dorsal view; 6: ditto, ventral view.

Tables

TABLE 1. Lengths (in µm) and proportions of legs of Polypedilum (Uresipedilum) simantokeleum. male (n = 4).

Fe	ti	ta1	ta2	ta3	ta4	ta5	LR	BV	SV
p1 870	640	–	–	–	–	–	–	–	–
p2 970	840	500	270	200	110	70	0.60	3.56	3.62
p3 1010	930	700	380	310	190	100	0.75	2.69	2.77