Dicrotendipes nudus, Qi, Xin, Lin, Xiao-Long & Wang, Xin-Hua, 2012

Qi, Xin, Lin, Xiao-Long & Wang, Xin-Hua, 2012, Review of Dicrotendipes Kieffer from China (Diptera, Chironomidae), ZooKeys 183, pp. 23-36 : 23-24

Dicrotendipes nudus sp. n. Figs 1−5

Diagnosis.

R1 and R4+5 without seta; tergite IX without median seta; anal point with basal peduncle and bulbous ventral extension, 6−9 dorsal basal setae and 6 lateral setae.

Description.

Male imago (n = 18)

TL 2.65−3.20, 2.95 mm. WL 1.65−2.00, 1.82 mm. TL/WL 1.58−1.94, 1.72. WL/Pfe 2.14−2.43, 2.31.

Coloration.Head, thorax and abdominal tergite VI−IX brown, abdominal tergite I−V pale yellow; legs yellowish-brown.

Head. AR 1.85−2.12, 2.02. Temporal setae 10−16, 13. Clypeus with 12−19, 16 setae. Tentorium 100−163, 146 µm long, 20−35, 28 µm wide. Palpomere lengths (in µm): 34−42, 35; 43−55, 48; 40-45; 108−130, 121; 130−148, 138; 163−215, 179. L: 5th/3 rd 1.35−1.67, 1.58. Frontal tubercle 10.20−17.50, 14.20 µm long, 5.00−7.50, 6.20 µm wide.

Wing (Fig. 1).Wing transparent, without markings. VR 1.11−1.16, 1.13. B 1−3, 2 setae; R with 7−11, 9 setae; R1 and R4+5 without seta. Squama with 4−6, 5 setae.

Thorax.Dorsocentrals 8−11, 10; acrostichals 4−5, 4; prealars 3−4, 4. Scutellum with 4−9, 7 setae.

Legs. Fore tibia with rounded scale lacking spur. Spurs on mid tibiae 23-25, 24 µm and 18−25,20 µm long, including combs 26-32, 30 µm and 26-32, 30 µm long; spurs on hind tibia 22-32, 26 µm and 18−20,19 µm long including combs 24-28, 26 µm and 22-25, 23 µm long. Width at apex of front tibia 53−58, 55 µm, of mid tibia 50−55, 53 µm, of hind tibia 55−65, 59 µm. Lengths (in µm) and proportions of legs in Table 1.

Hypopygium(Figs 2−5). Anal point 40−60, 50 µm long, with basal peduncle and bulbous ventral extension, 6−9 dorsal basal setae and 6 lateral setae. Tergite IX without median setae; laterosternite IX with 3−4, 3 setae. Phallapodeme 95−103, 97 µm long; transverse sternapodeme 40−50, 45 µm long, laterally narrowed, medially broad, inverted U-shaped. Gonocoxite 142−165, 156 µm long. Superior volsella 83−92, 85 µm long, 23−27, 25 µm wide; digitiform with short ventral extension; with numerous micro setae and 3−4 short apical setae (Figs 4−5). Inferior volsella 128−155, 142 µm long; elongate, apex bulbiform, with 6−9, 8 apical setae in 2 rows. Gonostylus 150−195, 172 µm long; slightly curved medially, with 5−7, 6 apical setae along inner margin. HR 0.73−1.17, 0.82; HV 1.82−1.88, 1.85.

Type materials.

Holotype: 1♂, China, Hebei: Chicheng County, 40°54.16'N, 115°54.08'E, 21.vii.2001, Guo YH, light trap. Paratypes (17): Hebei: 2♂♂, Chicheng County, 40°54.16'N, 115°54.08'E, 21.vii.2001, Guo YH, light trap; Xinjiang: 5♂♂, Hebahe County, 48°04.30'N, 86°24.47'E, 15.vii.2002, Tang HQ, light trap; Zhejiang: 3♂♂, Ningbo City, 29°48.36'N, 121°34.53'E, 10.v.2010, Qi X, sweeping method; 1♂, Sanmen County, 29°05.55'N, 121°23.45'E, 28.vii.2010, Lin XL, sweeping method; 6♂♂, Tiantai County, Huading Mountain, 29°14.51'N, 121°06.31'E,13.iv.2011, Lin XL, light trap.

Etymology.

The species name is from Latin, nudus, meaning bare, referring to R1 and R4+5 without seta, which is unique within the genus.

Remarks.

Dicrotendipes nudus closely resembles Dicrotendipes nervosus , but can be separated by R1 and R4+5 of Dicrotendipes nudus without seta; while in Dicrotendipes nervosus , R1 with 11−20, 15 setae, R4+5 with17−28, 22 setae.

Distribution.

The species is known from Hebei, Zhejiang Province and Xinjiang Uygur Autonomous Region of China.