Sciasmomyia thaii, 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 : 428-431

Sciasmomyia thaii sp. nov.

( Figs 88–100 )

Diagnosis. Face with brown median stripe and two brown Y-shaped lateral stripes. Mesonotum with pair of brown spots anteriorly, two grayish median stripes along inside of dc rows, becoming indistinctly separated in posterior third; anepisternum yellow and gray, with two brown spots on upper margin, and a brown spot medially and at base of anepisternal seta; katepisternum gray pruinose, with yellow on anterior 1/4 and on posterior 1/3. Wing with crossvein r-m incompletely surrounded by hyaline area, except above and below; hyaline spot in cell r4+5 above dorsal tip of crossvein dm-cu. Abdomen brown with grayish pruinosity laterally, tergites 2–6 each with pale brown posterior margin. Male with syntergosternite 7+8 forming short and narrow sclerite, fused to epandrium; epandrium blackish brown, moderately broad, and rounded apically; surstylus elliptical, but strongly emarginate mediodistally, with ventral, medially-directed bare lobes below emargination; hypandrial apodeme slender, slightly longer than apically conjoined lateral arms in ventral view; phallus narrow, subequal in length and height with hypandrium, consisting of pair of small acuate processes near middle, pair of acuate subapical processes, a Vshaped sclerite distally and a broad membranous process; phallapodeme (fused to phallus) narrow, notched posteriorly, with ventral ridge. Female with hypogynial valve broad and setulose, with basolateral wing-like extensions, narrowing to medial part, and extending apically into narrow glossy, bare process

Description. MALE. Body length 6.2–6.4 mm, wing length 6.3–6.6 mm. FEMALE. Body length 6.0– 6.7 mm, wing length 6.2–6.8 mm.

Head ( Fig. 89 ) yellow. Frons with two wide gray stripes extending to vertex, with brown spots at bases of vertical and fronto-orbital setae and brown stripes converging anteriorly to edge of lunule; ocellar triangle brown; oc strong, as long as posterior or. Face with brown median stripe on upper 2/3 and pair of brown Y-shaped lateral stripes, and narrow blackish brown stripe on ventral margin; parafacial yellow except for inner margin black, with brown spot at ventral corner. Gena about 1/2 height of eye, with large brown elliptical spot. Antenna yellow, except arista black after 1st aristomere; 1st flagellomere 1.3 times longer than high, with longest setulae shorter than 1/3 height of 1st flagellomere. Proboscis yellow except for thin brown longitudinal line medially and along lateral margin on labrum, and brown patch apicalolaterally on labellum. Palpus pale brown.

Thorax ( Figs 88, 90 ) yellow with grayish pruinosity. Mesonotum with pair of brown spots anteriorly, two grayish median stripes along inside of dc rows, to posterior 1/3 of mesonotum mostly grayish; scutellum with pair of brown spots basally; anepisternum yellow and gray, with two brown spots on upper margin, a small brown spot at base of anepisternal seta, one large brown spot medially, and brownish along posterior margin, and with gray pruinosity between spots; katepisternum mostly gray pruinose, yellow on anterior 1/4 and on posterior 1/3, and slightly darkened at bases of katepisternal setae. Legs yellow; femora brown on anterior surface (except one specimen entirely yellow on mid femur), with subapical brown ring, and entirely white at apex; tibiae pale, with brown subbasal and subapical rings, all basitarsi with a basal ring, tarsomere 2 pale and tarsomeres 3–5 pale brown. Fore femur with 5–7 pv and 5–6 pd, mid femur with 3–5 weak a and hind femur with 1 weak preapical ad. Wing ( Fig. 91 ) pale brown with hyaline spots, all of which display white on that part of the vein; subcostal cell with brown spot; series if spots along R2+3 alternating between small isolated spots and longitudinal spots extending to costal margin; series of irregular spots along R4+5, and along CuA1; crossvein r-m pale brown, surrounded by hyaline ring; hyaline spot in cell r4+5 above dorsal tip of crossvein dm-cu; 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 5.2:1.6:1; ultimate and penultimate sections of M 1 in proportion of 1.6:1; ultimate section of CuA1 about 1/10 of penultimate. Halter pale yellow.

Abdomen ( Fig. 92 ) brown with grayish pruinosity laterally on tergite, syntergite 1+2 and tergite 6 each laterally with pale yellowish spot (in some specimens, tergites 3–5 also with pale yellowish spot ( Fig. 93 )); tergites 2–6 each dark brown pruinose posterior margin. Female with eversible vescicle extending out from brown pleural membrane at level between tergites 5 and 6. Male genitalia ( Figs 94–98 ): syntergosternite 7+8 only forming short and narrow sclerite, fused to epandrium; epandrium blackish brown and moderately broad, rounded apically, with setae and setulae, with projecting anterior process bearing spiracle in lateral view; surstylus setulose, elliptical, but strongly emarginate mediodistally, with ventral, medially-directed bare lobes below emargination; hypandrial apodeme slender, slightly longer than lateral arms in ventral view, apically conjoined with a quadrate sclerite and a furcated apical process at middle of quadrate sclerite; phallus narrow, subequal in length and height with hypandrium, consisting of pair of small acuate processes near middle, pair of acuate subapical processes, a Vshaped sclerite distally and a broad membranous process; phallapodeme (fused to phallus) narrow, notched posteriorly, with ventral ridge. Female terminalia ( Figs 99, 100 ): Tergite 7 yellow dorsally and dark brown to black laterally; epiproct and hypoproct subtriangular, hypogynial valve broad, setulose, with basolateral wing-like extensions, narrowing to medial part, extending apically into narrow glossy, bare process.

Type material. Holotype 3 (CSCA): VIETNAM, Vinh Phue Province: Tamdao National Park, X–XI. 2011, Pham Hong Thai, ex. Malaise trap. Paratypes: same data as holotype (13, 1Ƥ CSCA; 13, 1Ƥ USNM).

Distribution. Vietnam (Vinh Phue).

Remarks. The new species is very similar to Sciasmomyia leishanensis sp. nov., S. longissima sp. nov., and S. meijerei , but can be separated from them by characteristics of the male and female genitalia.

Etymology. Named for the Vietnamese entomologist, Pham Hong Thai.

Figures

FIGURES 88 – 93. Sciasmomyia thaii sp. nov. Holotype male and paratype male (PT) and female. 88. male habitus, lateral view; 89. male (PT) head, anterior view; 90. male thorax, dorsal view; 91. male wing; 92. male abdomen, dorsal view; 93. female abdomen, lateral view.

FIGURES 94 – 100. Sciasmomyia thaii sp. nov. Paratype male. 94. syntergosternite 7 + 8 and epandrial complex, lateral view; 95. epandrial complex, posterior view; 96. syntergosternite 7 + 8 and epandrial complex, oblique lateral view; 97. phallus complex, ventral view; 98. phallus complex, lateral view. Paratype female. 99. abdomen tergites and sternites 5 – 9, lateral view; 100. hypogynial valve, ventral view.