Chlorops trisetifer, Cui, Yusi & Yang, Ding, 2011

Cui, Yusi & Yang, Ding, 2011, Species of Chlorops Meigen from Palaearctic China (Diptera, Chloropidae), Zootaxa 2987, pp. 18-30 : 24-26

Chlorops trisetifer sp. nov.

( Figs. 16–20 )

Diagnosis. Ocellar triangle brown, smooth, nearly as long as frons, with yellow lateral margins and posterior margin, with a black medial sulcus and a yellow sulcus on each side of triangle, and also with a yellow spot on each lateral margin of ocellar tubercle; ocellar tubercle black. 1st and 2nd antennal segments yellow, 3rd antennal segment slightly longer than high, black entirely; arista white, with yellow basal segment. Katepisternum with reddish-yellow lower portion, which has the black upper margin.

Description. Male. Body length 3.0– 3.2 mm. Wing length 2.1–2.2 mm.

Head yellow, nearly as long as high; frons about 0.9 times as long as wide, projecting only slightly in front of eye; gena broad, about 1.5 times as high as 3rd antennal segment, vibrissal angle obtuse. Ocellar triangle brown, smooth, nearly as long as frons, with yellow lateral margins and posterior margin, with a black medial sulcus and a yellow sulcus on each lateral margin, and also with a yellow spot on each lateral margin of ocellar tubercle; ocellar tubercle black. Setae on head black, and setulae yellow. Oc proclinate and divergent; vte and vti developed. Eyes covered mini setulae sparsely. 1st and 2nd antennal segments yellow, 3rd antennal segment longer than high slightly, black entirely; arista white, with yellow basal segment. Proboscis yellow with white setulae; palpus yellow with yellow setulae.

Thorax nearly as wide as head, yellow. Thoracic pleuron shinning yellow except for each postpronotum and region below prothoracic spiracle with a brown to brownish spot; anteroventral region of anepisternum with a black spot; katepisternum with reddish-yellow lower portion, which has the black upper margin; katepimeron with a black spot on lower margin, covered with tiny pale setulae; postnotum black; scutum nearly as long as wide, yellow anteriorly and reddish posteriorly, covered with short setulae and pale pollen, with 5 black stripes; scutellum yellow, but reddish medially, about 2.0 times as wide as long. Setae and setulae on thorax black. Legs long and thin, yellow, except for fore-femora brownish medially, tarsomeres brown and tarsomeres 4–5 black, setulae on leg black, short and strong. Wing hyaline, veins dark brown. Relative lengths of costal sections 2nd: 3rd: 4th = 15: 20: 15. Squama yellow with yellow setulae. Halteres bright yellow.

Abdomen yellow to brownish dorsally, yellow laterally and ventrally. Some specimens with blackish posterior margin on each tergum. Setulae on abdomen black.

Male genitalia ( Figs. 18–20 ): epandrium yellow with black setulae; surstylus long, nearly 0.5 times as high as epandrium, with posterior region long finger-like and curved forward, dark, with 2 processes; mesolobus heartlike; hypandrium relatively narrow in lateral view; pregonite longer than gonostylus; gonostylus broad medially, with 3 setulae posteriorly on each one; distiphallus oviform.

Female. Body length 3.7–4.0 mm. Wing length 2.7–2.9 mm. Similar to male.

Type material. Holotype 3, CHINA: Xinjiang: Habahe, 27. VII. 2007, Shan Huo. Paratypes 3, 2 Ƥ, same as holotype; 2 3, 2 Ƥ Jimusaer, 11. VIII. 2007, Shan Huo; 2 3, 3 Ƥ, Fukang, 11. VII. 2007, Wanzhi Cai.

Distribution. China (Xinjiang).

Remarks. The new species is somewhat similar to Chlorops stigmatella Becker, 1911 from Australia, China ( Taiwan), and Japan in the ocellar triangle brown, smooth, with the yellow lateral margins and posterior margin, with a black medial sulcus and a sulcus on each side of the triangle, and also with one yellow spot on each lateral margin of the ocellar tubercle; ocellar tubercle black. But it can separated from the latter by the palpus short, not projecting beyond peristoma, shorter than 0.6 times of the vertical diameter of an eye, without a concavity on the outer dorsolateral surface; the pregonite longer than the gonostylus; and the gonostylus broad medially, with 3 setulae posteriorly on each one. In C. stigmatella Becker , the palpus are long, projecting beyond peristoma, about 0.6 times as long as the vertical diameter of an eye, with a longitudinal concavity on the outer dorsolateral surface; the pregonite is as long as the gonostylus; and the gonostylus is broad anteriorly, and with many setulae posteriorly on each one ( Kanmiya, 1978).

Etymology. The species is named for the gonostylus with 3 setulae posteriorly.

Figures

FIGURES 16 – 20. Chlorops trisetifer sp. nov. Male. 16. Head, dorsal view; 17. antenna, lateral view; 18. epandrium, posterior view; 19. epandrium, lateral view; 20. hypandrium and phallic complex, ventral view. Scale bar of 16 = 0.50 mm, 17 = 0.33 mm, 18 – 19 = 0.25 mm, 20 = 0.22 mm.