Centorisoma neimengguensis, Liu, Xiaoyan & Yang, Ding, 2014

Liu, Xiaoyan & Yang, Ding, 2014, Five new species of Centorisoma Becker from China, with an updated key to world species (Diptera, Chloropidae), Zootaxa 3821 (1), pp. 101-115 : 108-110

Centorisoma neimengguensis sp. n.

Figs 3 , 20–26

Diagnosis. Gena broad, as wide as postpedicel. Postpedicel 1.5 times as long as its basal breadth. Cercus developed, trapezoidal, slightly thinner apically. Postgonite with minute serrations on inner margin near basiphallus and not produced beyond basiphallus.

Description. Male. Body length 3.8 mm, wing length 2.9 mm.

Head black without microtomentum, 0.9 times as long as high, 1.1 times as wide as thorax; face yellow, somewhat concave in lateral view, facial carina indistinct; frons yellow except two sides of ocellar triangle brown, 0.8 times as long as wide, projecting only slightly in front of eye; gena yellow with a brown triangular medial spot more or less on ventral 1/2, posterior 1/2 with lower margin brown, broad, as wide as postpedicel; parafacial narrow, yellow. Ocellar triangle black, smooth, shiny, reaching to anterior margin of frons, with pointed apex; ocellar tubercle light black. Cephalic setae and setulae black; oc and poc hair-like, oc as long as poc; vte and vti developed, vte as long as vti. Antenna dark brown with thick grayish microtomentum except ventral 1/2 of postpedicel yellow; postpedicel 1.5 times as long as its basal breadth, nearly parallel-sided; arista white except basal segment yellow, with short white setulae. Proboscis and palpus yellow with yellow setulae.

Thorax brown with microtomentum, evenly covered with short setulae. Scutum with granulated microsculpture, 1.1 times as long as wide. Thoracic pleuron shiny brown without microtomentum except for anteroventral portions of anepisternum and anepimeron, ventral 2/3 of katepisternum and ventral portion of katepimeron black. Scutellum 0.6 times as long as wide; ap sc short, slightly longer than scutellum. Setae and setulae on thorax black; npl 1+2, a npl hair-like, p npl developed, a npl subequal to p npl; a pa and p pa developed, a pa 2 times as long as p pa; 1 dc developed, as long as a pa. Legs yellow except fore femur and tibia yellowish brown with knee yellow; mid and hind femora, mid tibia brown with distal portions yellow; middle 1/3 of hind tibia, fore tarsus, mid tarsomeres 4–5 and hind tarsomere 5 brown. Setulae on legs brown. Mid tibia with a distinct black subapical spur nearly as long as diameter of tibia. Tibial organ oblong, narrow. Wing 2.8 times as long as wide, hyaline; veins brown. Relative lengths of 2nd: 3rd: 4th costal sections = 2.6: 1.6: 1; crossveins r-m and mm not approximate, r-m at basal 0.55 of discal cell. Halter pale yellow on knob, brown on stem.

Abdomen shiny brown; venter yellow. Setulae on abdomen brown.

Male genitalia ( Figs. 20–23 ): Epandrium brown with many setulae; surstylus horizontally articulated with epandrium, strongly narrowed at apex. Cercus well developed, trapezoidal, slightly thinner apically, articulated with distinct inner surstylar plate. Gonites arranged in a row, with a distinct demarcation at middle; postgonite gradually narrowed distally, not produced beyond basiphallus and bearing minute serrations on inner margin near basiphallus; basiphallus short; phallapodeme long, extended to base of basiphallus, with basal stalk broad in lateral view. Hypandrium broad.

Female. Body length 4.3 mm, wing length 2.8 mm.

Female genitalia ( Figs. 24–26 ): Tergite 9 pentagonal, about as long as wide, with 4 long setae; sternite 9 long, apically slightly pointed with long stout setae. Cercus short and stout with some long setae.

Type material. Holotype ♂, CHINA: Inner Mongolia: Helan Mountain, Shuimogou, Zhenggou, 5. VIII.

2010, Yan Li. Paratypes 1 ♂, same date as holotype; 2 ♂, Helan Mountain, Shuomogou, Zhenggou, 5. VIII. 2010, Lihua Wang; 3 ♂, Helan Mountain, Gulaben, Xiangchizigou, 5. VIII. 2010, Yan Li; 1 ♂, Helan Mountain, Gulaben, Zhonggutian, 8. VIII. 2010, Yan Li; 1 ♀, Helan Mountain, Gulaben, Gutian, 8. VIII. 2010, Weina Cui; 1 ♂, 1 ♀, Helan Mountain, Nansi, 14. VIII. 2010, Lihua Wang.

Distribution. China: Inner Mongolia.

Remarks. The new species is somewhat similar to C. mongolicum Nartshuk in having the gena broad, as wide as postpedicel and the postpedicel 1.5 times as long as its basal breadth. It can be separated from the latter by the following features: scutum without microtomentum except for small portion anterior to scutellum; legs yellow except fore femur and tibia yellowish brown with knee yellow, mid and hind femora, mid tibia brown with distal portions yellow, middle 1/3 of hind tibia, fore tarsus, mid tarsomeres 4–5 and hind tarsomere 5 brown. In C. mongolicum , the scutum has 2 longitudinal microtomentose stripes; the legs are yellow except for the fore leg, mid and hind femora, hind tibia slightly darkened ( Nartshuk 1968).

Etymology. The species is named after the type locality Inner mongolia.

Figures

FIGURE 3. Centorisoma neimengguensis sp. n., male. body, lateral view. Scale bar = 0.5 mm.

FIGURES 20 – 23. Centorisoma neimengguensis sp. n., male. 20 epandrium, posterior view; 21 epandrium, lateral view; 22 hypandrium and phallic complex, ventral view; 23 hypandrium and phallic complex, lateral view. Scale bar = 0.1 mm.

FIGURES 24 – 26. Centorisoma neimengguensis sp. n. female. 24 abdominal terminalia, dorsal view; 25 abdominal terminalia, lateral view; 26 abdominal terminalia, ventral view. Scale bar = 0.1 mm.