Lasiosina nigrolineata, Liu, Xiaoyan & Yang, Ding, 2016

Liu, Xiaoyan & Yang, Ding, 2016, Two new species of genus Lasiosina Becker from China (Diptera, Chloropidae), Zootaxa 4168 (2), pp. 382-388 : 383-385

Lasiosina nigrolineata sp. n.

Figs. 1–6

Diagnosis. Gena 1.5x as wide as first flagellomere. Ocellar triangle shining yellow except for black lateral margins and anterior 1/2, anterior 1/3 extremely narrow, extending to anterior margin of frons, with a black medial sulcus. Surstylus short, broad basally, distal 1/2 incurved, narrowed distally.

Description. Male. Body length 2.9–3.2 mm, wing length 2.1–2.4 mm.

Head yellow with gray microtomentum, 0.8x as long as high; face somewhat concave in lateral view, facial carina indistinct; frons 0.8x as long as wide, projecting only slightly in front of eye; gena broad, 1.5x as wide as first flagellomere; parafacial narrow. Ocellar triangle occupying 1/3 of posterior width of frons, shining yellow except for black lateral margins and anterior 1/2, anterior 1/3 extremely narrow, extending to anterior margin of frons, with a black medial sulcus; ocellar tubercle light black. Occiput yellow except for black middle 1/3. Clypeus light black. Cephalic setae and setulae black. Antenna yellowish brown with thick grayish microtomentum except for black distal margin of pedicel and first flagellomere; first flagellomere as wide as long; arista black with short black setulae. Proboscis brownish with yellow setulae; palpus yellowish brown with yellow setulae.

Thorax yellow with gray microtomentum. Postpronotum with a black spot. Scutum as long as wide, with 5 black longitudinal stripes, medial stripe slightly broad and extending to scutoscutellar suture, distal 1/4 of medial stripe brown; basal 2/3 of lateral stripe narrow; sublateral stripe short and narrow, mostly fused with lateral stripe.

Thoracic pleuron shiny yellow without microtomentum except for brown paratergite; black anteroventral portion of anepisternum, anterior portion of anepimeron, ventral 1/2 of katepisternum and ventral 1/3 of katepimeron. Postnotum black. Scutellum yellow except for brown lateral margins, short, rounded, 0.5x as long as wide; ap sc developed, as long as scutellum; sap sc 0.5x as long as scutellum. Setae and setulae on thorax black, developed; npl 1+2, a npl slightly longer than p npl; a pa developed, p pa hair–like, a pa 2x as long as p pa; 1 dc, 2x as long as a pa. Legs brown except for yellow coxae, trochanters, distal tips of femora, basal parts of tibiae, mid and hind tarsi and brown mid and hind tarsomeres 5. Setulae on legs black. Mid tibia with a distinct black apical spur, which is as long as diameter of tibia. Wing 2.6x as long as wide, hyaline; veins brown. Proportions of costal sectors 2–4 in the ratio 2: 1: 1.2; r–m at basal 0.6 of discal cell. Halter pale yellow on knob, brownish on stem.

Abdomen yellowish brown with gray microtomentum except for yellow basal portion of tergite 1 and distal portion of tergite 5; venter yellow. Setulae on abdomen black.

Male genitalia ( Figs. 3–6 ): Epandrium brown with long brown setulae, inner posteroventral magins approximated; surstylus short, broad basally, distal 1/2 incurved, narrowed distally, with small spinous processes on inner apicolateral margin. Cercus small, triangular in ventral view, with 1 pair of setulae. Gonites arranged in a row; postgonite 0.7x as long as pregonite, postgonite slightly incurved distally with pointed apex, with some sensory setulae, gradually narrowed basally; pregonite narrowed basally, pointed distally; distiphallus and basiphallus short; phallapodeme long, beyond basal margin of hypandrium with basal stalk broad in lateral view. Hypandrium narrowed.

Female. Unknown.

Type material. Holotype ♂, CHINA: Inner Mongolia: Helan Mountain, Gulaben, Xiangchizigou , 12. VIII. 2010, Coll. Yan Li . Paratypes 6 ♂, collection data same as of holotype. 1 ♂, Helan Mountain, Gulaben, Luanchaigou , 10. VIII. 2010, Coll. Yan Li . 1 ♂, Helan Mountain, Shuimogouzhenggou , 5. VIII. 2010, Coll. Yan Li . 3 ♂, Helan Mountain, Shuimogouzhenggou , 5. VIII. 2010, Coll. Lihua Wang.

Distribution. China (Inner Mongolia).

Remarks. The new species is somewhat similar to L. divitata Nartshuk , but can be separated from the latter by the following features: legs brown except for yellow coxae, trochanters, distal tips of femora, basal parts of tibiae, mid and hind tarsi and brown mid and hind tarsomeres 5; surstylus short, 0.2x as high as epandrium in lateral view. In L. divitata , legs are yellow except for fore and hind femora and tibiae with black macules, tarsi blackish; surstylus is long, 0.3x as high as epandrium in lateral view ( Nartshuk 2006).

Etymology. The specific name is from the Latin nigr– (“black”) and lineatus (“linear”), referring to the black and linear medial sulcus of the ocellar triangle; a feminine adjective.

Figures

FIGURES 1 – 2. Lasiosina nigrolineata sp. n., male. habitus, lateral view. Scale bar = 0.5 mm.

FIGURES 3 – 6. Lasiosina nigrolineata sp. n., male. 3 male terminalia, posterior view; 4 male terminalia, lateral view; 5 hypandrium and phallic complex, ventral view; 6 hypandrium and phallic complex, lateral view. Scale bar = 0.1 mm.