Phyllomyza obliquusa, Xi & Yin, 2018

Xi, Yuqiang & Yin, Xinming, 2018, Four new species of Phyllomyza Fallén (Diptera: Milichiidae), with an updated key from China, Zoological Systematics 43 (3), pp. 309-316 : 313-314

Phyllomyza obliquusa sp. nov. ( Figs 9–12 )

Diagnosis. This new species is somewhat similar to P. angustigenis Xi & Yang , but differs from the gena approximately one-ninth of eye height; knob of halter with the upper half brownish black and the lower greyish white; the surstylus with upper blade of bifurcated extremely swollen. In P. angustigenis , the gena approximately one-eleventh of eye height; knob of halter white; the surstylus with upper blade of bifurcated slightly swollen (Xi & Yang, 2013).

Description. Male. Body length 1.6 mm; wing length 1.6 mm.

Head ( Fig. 9 ) black with grayish microtomentum. Orbital plate subshiny black with microtomentum, ocellar triangle black without microtomentum; lunule strap-shaped, dark yellow with brownish yellow margin. Posterior eye margin ventrally diverging from head margin, eye 1.3 times as high as long, gena approximately one-ninth eye height. Setae and setulae on head black; ocellar triangle with 2 long ocellar setae and 3 short setae; frons with 3 orbital and 2 frontal setae on darkish brown stripe, orbital setae lateroclinate and frontal setae medioclinate, 4 interfrontal setae; postocellar setae cruciate. Lunule with 2 setae. Vibrissal angle relatively blunt, vibrissa strong and located at level of lower eye margin. Antenna blackish brown with brownish microtomentum; pedicel with short black setae at middle and margin, longest one about 4 times longer than others; first flagellomere with pubescence, irregularly circular; arista black, distinctly pubescent, 3.5 times as long as first flagellomere. Proboscis short and folded, darkish yellow with short sparse black setulae. Palpus darkish brown, thick rodlike with blunt apex, basal thicker than apical in lateral view, about 0.4mm, 5 times longer than wide, margin with short sparse black setae.

Thorax darkish brown with grey microtomentum, except mesonotum shiny blackish brown with sparse black microtomentum; scutellum darkish brown with gray microtomentum. Setae and setulae on thorax black; 1 h, 2 dc, 1 prsc, 2 npl, 1 prs, 1 sa, 1 pa, 1 kepsts (a row setulae at forward position); scutellum 2 times wider than long, with pair of asc and bsc, asc 3 times longer than bsc. Legs slender, coxae and femora darkish brown, tibiae dark brown except fore tibia darkish yellow with yellowish both ends, tarsi yellowish. Setae and setulae on legs black. Mid tibia with 1 black preapical dorsal seta. Wing ( Fig. 10 ) hyaline; veins brown; Sc strong; M 1 between r-m and dm-cu much longer than dm-cu. Calypter yellowish, with dense brownish microtrichae and margin with long setulae. Knob of halter with the upper half brownish black and the lower greyish white.

Abdomen darkish brown with gray microtomentum. Setae and setulae on abdomen black; T2–T5 with setae, marginal setae longer than others; sternites with sparse black setulae at posterior 3/4. Posteromedial triangular projection of T1 into T2 strong; S2 approximately trapezoid-shaped, apical margin 2 times wider than basal margin, S3 and S4 generally trapezoidal, the apical margin 1.5 times wider than basal margin, S5 horizontally rectangular, the apical margin slightly arched, 2 times longer than wide. Male genitalia ( Figs 11–12 ). Epandrium with 10 pairs of strong setae; surstylus with upper blade of bifurcated tip extremely swollen and lower one relatively thin; cercus arched and with short sparse setae, the bottom margin with two protuberancies, covered parts of surstylus.

Female. Unkown.

Material examined. Holotype ♂, China, Yunnan, Yingjiang, Tongbiguan (24°36′N, 97°39′E; elev. 1350 m), 1. V.2012, coll. Wenliang Li. Paratypes. 3♂, same data as holotype ; 3♂, China, Yunnan, Tengchong, Datang (25°37′N, 98°40′E; elev. 1850 m), 8. V.2012, coll. Wenliang Li ; 2♂, China, Yunnan, Baoshan, Dahaoping (25°19′N, 99°12′E; elev. 1925 m), 4. V.2012, coll. Yuanye Liu. All deposited in HAU.

Distribution. China (Yunnan).

Etymology. The specific epithet refers to the inclined dm-cu.

Figures

Figures 9–12. Phyllomyza obliquusa sp. nov., male. 9. Head, lateral view. 10. Wing. 11. Epandrium, cerci, and surstyli, posterior view. 12. Epandrium, cerci, and surstyli, lateral view. Scale bars=0.1mm.