Sciasmomyia quadricuspis, 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 : 423-426

Sciasmomyia quadricuspis sp. nov.

( Figs 71–82 )

Diagnosis. Face yellow, transverse brown spot present between bases of antennae, brown median spot (these two spots fused in male), two brown oblique lateral spots. Mesonotum with two short brown median stripes near anterior margin, two long gray stripes extending from anterior margin to posterior margin (occasionally blurry posteriorly); anepisternum yellow with a black spot dorsally and a pale brown spot ventrally near posterior margin; katepisternum yellow with a black middle spot near upper margin. Wing mostly hyaline with irregular brown spots on basal 5/6 of upper half, and mostly brown with hyaline spots on lower half and on apical 1/6. Abdomen yellow with grayish white pruinosity, tergites 2–6 (and 7 in female) with wide black or gray central area. Male with syntergosternite 7+8 forming a complete ring, narrowly fused dorsally with epandrium; epandrium broad and rounded in lateral view; hypandrium with hypandrial apodeme subequal in length to lateral arms, with lateral arms broad and incurved apically with 3–6 setulae; phallus with two pairs of subuliform processes in ventral view; phallapodeme narrowly separated from and slightly longer than phallus. Female with hypogynial valve broad with three processes, setulose in ventral view.

Description. MALE. Body length 4.8–5.0 mm, wing length 5.1–5.2 mm. FEMALE. Body length 4.2–4.5 mm, wing length 5.2–5.4 mm.

Head ( Fig. 72 ) yellow. Frons with two pale brown stripes extending to vertex; ocellar triangle gray; oc longer than posterior or. Face with transverse brown spot between bases of antennae, a brown median spot (these two spots fused in male), two brown oblique lateral spots, and three brown spots along ventral margin; parafacial yellow except for inner margin brown on ventral 1/2, with a brown spot at ventral corner. Gena about 1/2 height of eye, with a large brown spot. Antenna yellow, 1st flagellomere 2.0 times longer than high; arista with longest setula shorter than 1/4 height of 1st flagellomere. Proboscis. brown. Palpus brown.

Thorax ( Fig. 73 ) yellow. Mesonotum with two short brown median stripes near anterior margin, two long gray stripes extending from anterior margin to posterior margin (occasionally blurry posteriorly); anepisternum yellow with a black spot dorsally and a pale brown spot ventrally near posterior margin; katepisternum yellow with a black middle spot close to upper margin. Legs yellow; fore femur with brown mark on posterior surface subapically, mid femur with brown dorsobasal spot and on ventral surface subapically, hind femur with brown dorsobasal spot and subapical ring; tibiae each with brown ventral spot subbasally and subapical ring. Fore femur with 5 pv, 8 pd, mid femur with 4 weak a, hind femur with 1 weak preapical ad. Wing ( Fig. 71 ) mostly hyaline with irregular brown spots on basal 5/6 of upper half, and mostly brown with irregular hyaline spots on lower half and in apical 1/6, with pale brown areas displaying brown on that part of vein, and with hyaline areas displaying white on that part of the vein; 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 5:1.5:1; ultimate and penultimate sections of M 1 in proportion of 1:1.6; ultimate section of CuA1 about 1/12 of penultimate. Halter yellow.

Abdomen yellow with sparse grayish white pruinosity, tergites 2–6 (and 7 in female) with wide black or gray central area ( Figs 74, 75 ). Male genitalia ( Figs 76–79 ): syntergosternite 7+8 yellow except for black around spiracle, forming a complete ring, narrowly fused dorsally with epandrium; epandrium yellow, broad and rounded, with pair of long dorsal setae in lateral view; surstylus as pair of yellow elliptical sclerites with setulae; hypandrium with hypandrial apodeme subequal in length to lateral arms, with lateral arms broad and incurved apically with 3–6 setulae; phallus with two pairs of subuliform processes in ventral view; phallapodeme narrowly separated from and slightly longer than phallus. Female terminalia ( Figs 80–82 ): tergite and sternite 8 pale yellow; hypogynial valve broad with three processes, setulose in ventral view.

Type material. Holotype 3 (CASC): CHINA, Hubei Province: West Hupeh, Lichuan District, Leong-Ho- Kow, 1. IX. 1948, J. L. Gressitt & Djou. Paratypes: CHINA, Hubei Province: same data as holotype, but 9. IX. 1948 (13, CASC); Jiangxi Province: Kiangsi SE., Hong San, 23–26. VI. 1936, A. L. Melander (23, 2Ƥ, USNM).

Distribution. China (Hubei, Jiangxi).

Remarks. The new species is one of two species (the other being S. tubata sp. nov.) with the phallapodeme narrowly separated from the base of the phallus. The wing pattern is unique in being mostly hyaline with irregular brown spots on the basal 5/6 of the dorsal half. The species is also distinct with the abdomen having a wide black or gray central area, and entirely yellow laterally.

Etymology. Latin, quadri, meaning four + cuspis, meaning acuate at tip; refers to the phallus having two pairs of subuliform processes in ventral view; a feminine adjective.

Figures

FIGURES 71 – 75. Sciasmomyia quadricuspis sp. nov. Holotype male. 71. habitus, lateral view; 72. head, anterior view; 73. thorax, dorsal view; 74. abdomen, dorsal view. Paratype female. 75. abdomen, dorsal view.

FIGURES 76 – 82. Sciasmomyia quadricuspis sp. nov. Paratype male. 76. syntergosternite 7 + 8 and epandrial complex, lateral view; 77. syntergosternite 7 + 8 and epandrial complex, posterior view; 78. phallus complex, ventral view; 79. phallus complex, lateral view; 80. abdomen tergites and sternites 5 – 9, lateral view; 81. hypogynial valve, ventral view; 82. spermathecae. Scale 0.1 mm. Abbreviation: pa = phallapodeme.