Pseudorthocladius (Pseudorthocladius) ovatus, Ren, Jing, Lin, Xiaolong & Wang, Xinhua, 2014

Ren, Jing, Lin, Xiaolong & Wang, Xinhua, 2014, Review of genus Pseudorthocladius Goetghebuer, 1943 (Diptera, Chironomidae) from China, ZooKeys 387, pp. 51-72 : 60-61

Pseudorthocladius (Pseudorthocladius) ovatus sp. n. Figures 19-23

Diagnosis.

The male imago can be distinguished from the known species of the genus by the following combination of characters: anal point round baring 9 long and strong setae; inferior volsella oval with round margin and bearing 8 long and stout marginal setae; high AR(1.40).

Description.

Adult male (n = 5). Total length 2.90-3.20, 2.98 mm. Wing length 1.43-1.55, 1.47 mm. Total length/wing length 1.88-2.08, 2.00. Wing length/length of profemur 2.26-2.41, 2.35.

Coloration. Head, abdomen, legs brown; thorax with yellow ground with brown preepisternum and brownish black postnotum.

Head. Antenna with 13 flagellomeres. Terminal flagellomere length 410-460, 440 μm. AR 1.31-1.55, 1.40. Temporal setae 8-11, 10, including 3-7, 4 inner verticals, 5-6, 5 outer verticals, and 0-1, 1 postorbital. Clypeus with 8-12, 10 setae. Tentorium 120-132, 126 μm long, 31-33, 32 μm wide. Palpomere lengths (in μm): 31-36, 32; 43-45, 44; 105-108, 107; 155-158, 156; 201-207, 204. L: 5th/3rd 1.81-1.96, 1.91.

Wing (Figure 19). VR 1.19-1.26, 1.21. Anal lobe well–developed. Brachiolum with 1 seta; R with 10-12, 10 setae; R1 with 3-4, 3 setae; other veins bare. Squama 14-18, 16 setae. Costa extension 36-50, 46 μm long. Cu1 slightly curved.

Thorax (Figure 20). Antepronotum with 5-8, 6 lateral setae, dorsocentrals 20-25, 22, acrostichals 8-12, 10, prealars 7-8, 8. Scutellum with 12-17, 15 setae.

Legs. Pulvilli present. Spur of fore tibia 45-48, 46 μm long, spurs of mid tibia both 19-24, 22 μm long; hind tibia with a long spur 48-52, 50 μm long, a short spur 17-24, 22 μm long and comb composed of 12-14, 13 spines. Width at apex of fore tibia 38-43, 41 μm, of mid tibia 31-40, 36 μm, of hind tibia 43-48, 45 μm. Lengths (in μm) and proportions of legs as in Table 8.

Hypopygium (Figures 21-23). Laterosternite IX with 6-7, 6 setae. Tergite IX with round anal point, bearing 9-10, 9 long and strong setae. Phallapodeme 36-40, 38 μm long. Transverse sternapodeme 72-84, 81 μm long. Virga absent. Gonocoxite 153-168, 162 μm long with oval inferior volsella (Figure 23) with rounded margin and bearing 8 long, stout marginal setae. Gonostylus 89-96, 98 μm long, with small crista dorsalis. Megaseta 5-7, 6 μm long. HR 1.70-1.89, 1.75. HV 3.18-3.23, 3.22.

Female, pupa and larva unknown.

Type materials.

Holotype: ♂ (BDN No.26746), China: Zhejiang Province, Wenzhou City, Taishun County, 27°33'N, 119°39'E, 1.viii.2005, Bingchun Ji, light trap. Paratypes (4 ♂♂): 3 ♂♂, Zhejiang Province, Tianmu Mountain, 30°19'N, 119°26'E, 8.ix.1998, Xinhua Wang, light trap; 1 ♂, Zhejiang Province, Lishui City, Qingyuan county, 27°39'N, 119°09'E, 13.vii.1994, Hong Wu, sweep net.

Etymology.

The specific name is from Latin, ovatus, meaning egg–shaped, referring to the oval inferior volsella.

Remarks.

The new species is close to Pseudorthocladius (Pseudorthocladius) matusecundus Sasa & Kawai, 1987 in the structure of hypopygium, but can be separated from the latter on the basis of characters in Table 9.

Distribution.

The new species is known from Zhejiang Province in Oriental China.