Polypedilum (Tripodura) enshiense Song & Wang

Yan, Chuncai, Song, Chao, Liu, Ting, Zhao, Guangjun, Hou, Ziyuan, Cao, Wei & Wang, Xinhua, 2017, Two new and one newly recorded species of Polypedilum Kieffer 1912 with DNA barcodes from Oriental China (Chironomidae: Diptera), Zootaxa 4238 (1), pp. 109-118 : 110-112

Polypedilum (Tripodura) enshiense Song & Wang sp. n.

( Figure1A–G , GenBank accession number KY370969 )

Type material. Holotype: ♂ (BDN No. CH 39) . China: Hubei Province, Enshi autonomous prefecture, Qizimeishan National Nature Reserve , 109.82°E, 30.06°N, 10. VII. 2016, Song C, Sweeping net; Paratypes: 2♂♂, data as holotype .

Etymology. Named after the type locality, Enshi autonomous prefecture.

Diagnosis. The male adult can be separated from the previous recorded species of the subgenus by the following combination of characters: wing patterns (numbers and locations of wing plots), strong and long lateral projection of anal point and subrectangular superior volsella with one apical outer seta.

Description. Male adult (n = 3).

Total length 2.17–2.84, 2.50 mm. Wing length 1.50–1.60, 1.56 mm. Wing length /length of profemur 2.31– 2.48, 2.40.

Coloration. Head, thorax and abdomen dark brown, except hypopygium yellowish. Wing with five spots. Legs yellowish except basal 2/3 of fermora brown ( Figure 1A ).

Head. Frontal tubercles absent. AR 0.81–0.90, 0.86. Ultimate flagellomere 355–390, 380 µm long; temporal setae 8–11 including 4–6 inner verticals, 2–4 outer verticals and 2–3 postorbitals. Clypeus with 11–13 setae. Tentorium 92–98 µm long, 23–26 µm wide. Palpomere lengths (in µm): 25; 28–30, 29; 48–63, 55; 65–83, 74; 110– 115, 113. Length of palpal segment 5th/3rd 1.74–2.40, 2.07.

Wing ( Figure 1B ). Anal lobe developed. VR 1.22–1.25, 1.23. Brachiolum with 1 seta, R with 12–16, 14; R1 with 7–10, 9; R4+5 with 9–13, 11 setae. Squama with 4–5 setae. 1 spot locates in basic part of cell r4+5, 1 in middle of cell m1+2, 1 in basic portion of cell m3+4, 1 in distal of cell cu adjacent to spot in cell m3+4 and 1 in middle of cell an.

Thorax. Dorsocentrals 8–12; acrostichals 5–8; scutellum with 1–3 setae; prealars 4–4, 4 setae.

Legs ( Figure 1C ). Terminal scale ( Figure 1D ) of front tibia pointed, 25–37, 29 µm long. Spur on median tibia 45–47, 46 µm long with comb including 6–7 lateral teeth; un-spurred comb including 15–16 lateral teeth; spur on posterior tibia 45–48, 47 µm long with comb including 6–8 lateral teeth, un-spurred comb including 24–28 lateral teeth. Lengths (in µm) and proportions of legs as in Table 1.

Fe Ti Ta1 Ta2 Ta3 Ta4

P1 605–690, 650 390–430, 410 700–770, 740 410–465, 440 320–350, 330 230–250, 240 P2 700–760, 730 515–560, 540 275–290, 280 155–170, 160 100–125, 110 65–75, 70

P3 750–810, 790 635–700, 670 400–440, 420 230–250, 240 200–225, 215 130–135, 133 Ta 5 W. Ti BR LR BV SV

P1 125–135, 130 32–35, 34 3.13–3.57 1.79–1.82, 1.80 1.56–1.58, 1.57 1.41–1.45, 1.43 P2 50–65, 60 35–35, 35 5.00–5.00 0.51–0.56, 0.52 3.69–4.69, 3.89 4.19–4.65, 4.50 P3 85–85, 85 35–35, 35 5.89–6.89 0.63–0.63, 0.63 2.76–2.80, 2.78 3.43–3.46, 3.45 Hypopygium ( Figure 1E–G ). Anal tergite with 4–5 median setae, laterosternite with 2–3 setae. Anal point with rounded apex in dorsal aspect, 32–40, 35 µm long; lateral projection 25–30, 28 µm long, covered with michrotrichia. Transverse sternapodeme 30–35, 33 µm long. Superior volsella ( Figure 1G ) 32–45 µm long, subrectangular shape, covered with microtrichia and apical portion with some long setae and one strong apical outer seta. Inferior volsella slender, 90–95, 92 µm long with 7 strong setae. Gonostylus 112–130, 118 µm long, 4–6 strong setae along distal inner margin. HR 0.98–1.02, 1.01; HV 1.85–2.37, 2.07.

Female and immature unknown.

Remarks. Wing spots pattern of the new species resembles P. (T.) tobaundecima Kikuchi & Sasa, 1990 , P. (T.) nudiprostatum Zhang & Wang, 2006 and P. (T.) unifascia ( Tokunaga, 1938) , but it can be distinguished by the ringed legs, long lateral projection of anal point. The structure of hypopygium in new species is similar with P. (T.) rectangulum Hazra, Sanyal & Brahma, 2016 , but with different wing patterns (numbers and locations of spot) and broad anal point.

In addition, the COI sequence of holotype was blasted using the identification function in BOLD (BOLD, http://www.boldsystems.org; Ratnasingham & Hebert 2007) on Oct 22, 2016 and returned with a neighbor joining tree ( Figure 2 ) based on Kimura 2 Parameter distance model. Obviously, the species formed a distinct clade and supported it differentiated from barcoded Polypedilum species.

Distribution. The species is known from its type locality, Qizimeishan National Nature reserve, Enshi autonomous prefecture, Hubei province, China. The specimens were collected by sweeping net near an alpine wetland.

Figures

FIGURE 1 A – G. P. (T.) enshiense Song & Wang sp. n. A—Body in dorsal view; B—Wing; C—Legs; D—Scale of front tibia; E—Dorsal view of hypopygium; F—Ventral view of hypopygium; G—Superior volsella.

FIGURE 2. Neighbor joining sub-tree, with Kimura 2 parameter generated from BOLD, scale represents K 2 P genetic distance.