Sciasmomyia longicurvata, Shi, Li, Gaimari, Stephen D. & Yang, Ding, 2013

Shi, Li, Gaimari, Stephen D. & Yang, Ding, 2013, Revision of Sciasmomyia Hendel (Diptera: Lauxaniidae), with eight new species, Zootaxa 3691 (4), pp. 401-435 : 411-412

Sciasmomyia longicurvata sp. nov.

( Figs 27–35 )

Diagnosis. Frons with two narrow brown stripes not reaching vertex. Face with brown median stripe on upper 2/3 and pair of brown oblique lateral stripes, pale brown at ventral corner and blackish brown stripe on ventral margin. Mesonotum with two grayish median stripes, grayish brown between dc rows on posterior 1/3. Anepisternum yellow with three brown spots on anterodorsal, posterodorsal and posteroventral corners, and a brown median spot; katepisternum yellow with brown spot on anterodorsal corner and an oblique blackish brown stripe along dorsal margin. Wing with large round hyaline preapical spot on R2+3, and on R4+5 and M1 just basal to and proximal to crossvein r-m (those basal to crossvein confluent), and on M1 just proximal to crossvein dm-cu; distinctly hyaline apical margin between R2+3 and M1. Abdomen yellowish brown with whitish gray pruinosity, tergites 2–6 each with black posterior margin. Male with syntergosternite 7+8 forming complete ring; epandrium short and broad, with a small pad-like surstylus; hypandrium thick, clavate at tips of lateral arms and at base of hypandrial apodeme; phallus rounded apically with small dorsal incision and pair of black long curved knife-like lateral processes in lateral view.

Description. MALE. Body length 4.6–4.7 mm, wing length 5.0– 5.4 mm. FEMALE. Unknown.

Head ( Fig. 28 ) yellow. Frons with two narrow brown stripes not reaching to vertex; ocellar triangle grayish black; oc strong, as long as posterior or. Face with brown median stripe on upper 2/3 and pair of brown oblique lateral stripes, pale brown at ventral corner and blackish brown stripe on ventral margin; parafacial yellow except for inner margin black, with a brown elliptical spot at ventral corner. Gena about 1/2 height of eye, with brown elliptical spot. Antenna yellow, 1st flagellomere 1.7 times longer than high, arista with longest setula shorter than 1/3 height of 1st flagellomere. Proboscis pale brown. Palpus pale brownish yellow.

Thorax ( Fig. 29 ) yellow with whitish gray pruinosity. Mesonotum with two grayish median stripes, grayish brown between dc rows on posterior 1/3; anepisternum yellow with three brown spots on anterodorsal, posterodorsal and posteroventral corners, and a brown median spot; katepisternum yellow with brown spot on anterodorsal corner and an oblique blackish brown stripe along dorsal margin. Legs yellow, all basitarsi with brown basal ring, tarsomere 2 pale brown and tarsomeres 3–5 entirely blackish brown. Fore femur with 5 pv and 8 pd, mid femur with 4 weak a, hind femur with 1 weak preapical ad. Wing ( Fig. 30 ) pale brown with hyaline spots, all of which display white on that part of the vein; subcostal cell with brown spot; a large round hyaline preapical spot on R2+3 and on R4+5 and M1 just basal to and proximal to crossvein r-m (those basal to crossvein confluent), and on M1 just proximal to crossvein dm-cu; distinctly hyaline apical margin between R2+3 and M1; crossveins r-m and dm-cu brown, the former incompletely surrounded by hyaline area; costa with 2nd (between R1 and R2+3), 3rd (between R2+3 and R4+5) and 4th (between R4+5 and M1) sections in proportion of 5.2:1.2:1; ultimate and penultimate sections of M 1 in proportion of 1:1.3; ultimate section of CuA1 about 1/9 of penultimate. Halter pale yellow.

Abdomen yellowish brown with whitish gray pruinosity, tergites 2–6 each with deeply black posterior margin. Male genitalia ( Figs 31–35 ): syntergosternite 7+8 blackish brown forming complete ring, with a seta near spiracle and three pairs of ventral setulae; epandrium yellowish brown, broad, with three dorsal setae and two long subapical setulae; surstylus elliptical, sheet-like with long setulae; hypandrium broad, very long, with lateral arms clavate distally and hypandrial apodeme gradually broadening anteriorly; phallus long columnar and J-shaped curved, rounded apically with small dorsal incision and pair of black long curved knife-like lateral processes in lateral view; phallapodeme (fused to phallus) broad, distinctly clavate anteriorly.

Type material. Holotype 3 (IZAS, IOZ1218972): CHINA, Sichuan Province: E’mei mountain, Xixiangchi, 1800–1900 m, 8. VIII. 1957, Fuxing Zhu. Paratype: CHINA, Sichuan Province: E’mei mountain, Jiulaodong, 1800–1900 m, 23. VIII. 1957, Youcai Lu (13 (IOZ1218981), IZAS).

Distribution. China (Sichuan).

Remarks. The new species is similar to Sciasmomyia tubata sp. nov. in having the face with a pair of brown oblique lateral stripes (not Y- or V-shaped), and the wing having a distinctly apical hyaline apical margin between R2+3 and M1. But, the new species can be differentiated by color patterns on the katepisternum and abdomen, along with characteristics of the male genitalia. Females of the new species are unknown.

Etymology. Latin, longicurvata , meaning long and curved; refers to the phallus having a pair of long curved knife-like lateral processes; a feminine adjective.

Figures

FIGURES 27 – 30. Sciasmomyia longicurvata sp. nov. Holotype male. 27. habitus, lateral view; 28. head, anterior view; 29. thorax, dorsal view; 30. wing.

FIGURES 31 – 35. Sciasmomyia longicurvata sp. nov. Paratype male. 31. syntergosternite 7 + 8 and epandrial complex, lateral view; 32. epandrial complex, posterior view; 33. syntergosternite 7 + 8, posterior view; 34. phallus complex, ventral view; 35. phallus complex, lateral view. Scale 0.1 mm. Abbreviation: st = syntergosternite 7 + 8.