Polypedilum (Cerobregma) huapingensis Liu & Lin, 2021

Liu, Wen-Bin, Yao, Yuan, Yan, Chun-Cai, Wang, Xin-Hua & Lin, Xiao-Long, 2021, A new species of Polypedilum (Cerobregma) (Diptera, Chironomidae) from Oriental China, ZooKeys 1011, pp. 139-148 : 139

Polypedilum (Cerobregma) huapingensis Liu & Lin sp. nov. Figures 2 , 3 , 4

Type material.

Holotype: male (NKU & BOLD sample ID: LSHP43), China, Guangxi Zhuang Autonomous Region, Guilin City, Lingui County, Huaping National Nature Reserve, 25.563°N, 109.942°E, 1271 m a.s.l., 10-20.VI.2020, Malaise trap, S.G. Zhao.

Etymology.

The specific name refers to the Huaping National Nature Reserve, where the holotype was collected.

Diagnostic characters.

According to the morphological characters of the adult male, the new Polypedilum species keys to the subgenus Polypedilum Cerobregma , and can be distinguished from other known species of the subgenus by the following combination of characters: tergites III-VI brown with dark brown spots at middle; wing pale brown with a large black spot on entire basal area of wing; superior volsella with basal microtrichia and two inner setae; anal point strong, contracted in middle, a large inflated globe apically with candle-like spine.

Adult male

(n = 1). Total length 4.29 mm. Wing length 2.71 mm. Total length/wing length 1.58. Wing length/length of profemur 1.57.

Coloration (Fig. 2 ). Head brown. Antenna yellow. Thorax ground color brown with dark brown stripes on scutum, laterally under parapsidal suture, postnotum and on preepisternum. Tergites III-VI brown with dark brown spots at middle; tergites I, II, VII, and VIII and hypopygium largely dark brown. Most of femora and tibiae dark brown, all tarsomeres yellow. Wing pale brown with a large black spot on entire basal area.

Head (Fig. 3A ). Antenna with 13 flagellomeres; ultimate flagellomere 425 µm long; AR 0.44. Temporal setae 27, including 7 inner verticals and 20 outer verticals. Clypeus with 79 setae. Tentorium 132 µm long; 45 µm wide. Stipes 112 µm long, 24 µm wide. Lengths of palpomeres 1-5 (in µm): 52.5, 97.5, 192, 170, 232. Palpomere ratio (5th/3rd) 1.21.

Thorax (Fig. 3B ). Acrostichals 31; humerals 38; dorsocentrals 104; prealars 16. Scutellum with 86 setae.

Wing (Fig. 3C ). VR 1.15. Brachiolum with 13 setae; R with 36 setae; R1 with 32 setae; R4+5 with 36 setae; M with 22 setae; remaining veins bare. R2+3 distinct. Squama with 16 setae. Anal lobe moderately developed.

Legs. Spur of mid tibia 28 µm long, mid tibia including 55 µm long comb, un-spurs comb 35 µm long; spur of hind tibia 36 µm long including 78 µm long comb, un-spurs comb 40 µm long. Apical width of fore tibia 60 µm; of mid tibia 76 µm; of hind tibia 80 µm. Lengths (in µm) and proportions of legs as in Table 2 .

Hypopygium (Fig. 4 ). Anal tergite with 46 median setae. Laterosternite IX with seven setae. Anal point as in Fig. 4D , strong, contracted in middle, as a large inflated globe apically with a single candle-like spine, tapering, 143 µm long. Transverse sternapodeme 93 µm long; phallapodeme 168 µm long. Gonocoxite 320 µm long. Superior volsella 143 µm long, with basal microtrichia and two inner setae (Fig. 4E ). Inferior volsella 164 µm long, finger-shaped, divided into two lobes apically, with 24 long setae. Gonostylus 310 µm long. HR 1.03; HV 1.38.

Female and immatures unknown.

Discussion.

The characters of the anal point and superior volsella of the new species place it within the subgenus Polypedilum Cerobregma . The morphology of the new species resembles that of Polypedilum heberti Lin &Wang, 2019, but it can be separated from it on the basis of the following: 1) tergites III-VI brown with dark brown spots at middle in the new species, versus tergites III-VI with dark brown bands at middle in P. heberti ; 2) thorax of the new species (acrostichals 31; humerals 38; dorsocentrals 104) with much more setae than in P. heberti (acrostichals 8; humerals 5; dorsocentrals 20); 3) anal point strong and tapering in P. heberti , versus constricted in middle, with a large inflated globe apically with candle-like spine in the new species.

Figures

Figure 2. Polypedilum (Cerobregma) huapingensis Liu & Lin, sp. nov., holotype male.

Figure 3. Polypedilum (Cerobregma) huapingensis Liu & Lin, sp. nov., holotype male A head B thorax C wing. Scale bars: 200 µm.

Figure 4. Polypedilum (Cerobregma) huapingensis Liu & Lin, sp. nov., holotype male A hypopygium, dorsal view B hypopygium, ventral view C abdomen D superior volsella E anal point. Scale bars: 100 µm.