Dexia kurahashii Zhang et Shima, 2010

Zhang, Chun-Tian, Shima, Hiroshi & Chen, Xiao-Lin, 2010, A review of the genus Dexia Meigen in the Palearctic and Oriental Regions (Diptera: Tachinidae) 2705, Zootaxa 2705, pp. 1-81 : 45-47

Dexia kurahashii Zhang et Shima , sp. nov.

Figs. 53−56

Diagnosis. Prementum about 6 times as long as wide; inner and outer thoracic vittae merged on postsutural scutum; 3 katepisternal setae; legs black; abdominal tergites 3 to 5 each with a triangular black marking; syntergite 1+2 with 1 pair of median marginal setae.

Description. Body length. 9.1−14.3 mm.

Male. Head with yellowish white pruinosity; frontal vitta brownish black; gena reddish brown; 1st flagellomere yellow, pedicel reddish to brown; palpus reddish yellow. Frons 0.16−0.17 times as wide as head width; frontal vitta widened anteriorly, wider than fronto-orbital plate; parafacial about 3 times as wide as 1st flagellomere; facial carina well developed, flattened apically; gena 0.4−0.5 times as wide as eye height; lower margin of face slightly protruding forward. Inner vertical seta 0.4−0.5 times as long as eye height, outer vertical seta hair-like, 0.6−0.7 times as long as inner vertical seta; ocellar seta slightly longer than inner vertical seta; 11−12 inclinate frontal setae, lowest one nearly level with base of scape; vibrissa inserted slightly above level of lower margin of face. Antenna falling short of lower margin of face by 0.6−0.8 length of 1st flagellomere; 1st flagellomere 3.5−4 times as long as pedicel, total width of arista including plumosity about 4 times as wide as 1st flagellomere. Prementum about 6 times as long as wide; palpus longer than antenna.

Thorax black in ground color, with dense yellowish gray pruinosity on scutum, gray pruinosity on pleura except for anterior portion of katepisternum and anepimeron; with 2 pairs of longitudinal black vittae on dorsum, inner and outer vittae merged on posterior half of presutural scutum; scutellum reddish yellow on apical 3/5. All thoracic hairs black; proepisternum bare; postpronotal lobe with 3 setae nearly in a straight line; 1 presutural and 2 postsutural acrostichal setae; 2 presutural and 3 postsutural dorsocentral setae; 2 postsutural intra-alar setae; 3 supra-alar setae, 1st one about 1/4 as long as second, shorter than intra-alar seta; 3 katepisternal setae. Wing hyaline, yellowish at base, brown along veins C, R 1, R 2+3, and R 4+5; tegula and basicosta black; lower calypter yellowish. Costal spine about as long as crossvein r-m. Relative lengths of 2nd, 3rd, and 4th costal sectors approximately 5.5:12:5; vein M from dm-cu crossvein to its bend about 3 times distance between the bend and wing margin, appendix short; cell r 4+5 narrowly open at wing margin; last sector of vein CuA 1 about 1/2 as long as dm-cu crossvein. Lower calypter with short fringe on outer margin. Legs black, pulvilli brownish. Mid tibia with 2−4 posterodorsal setae; hind tibia with a row of 3−5 anterodorsal, 2 posterodorsal and 2 ventral setae.

Abdomen long ovate, translucent yellow, black on median excavation and anterolateral portion of syntergite 1+2 and a triangular black median marking on posterior 1/4−3/4 of each tergite; grayish white pruinosity on anterior margin of tergite 3, anterior 1/4−1/5 of tergite 4 and entire tergite 5. Syntergite 1+2 with 1 pair of median marginal and 1 lateral marginal setae; tergite 3 with 1−2 pairs of fine median discal, 1 pair of median marginal and 1−2 lateral marginal setae; tergites 4 and 5 each with 1−2 pairs of widely apart median discal and a row of marginal setae. Male terminalia. Sternite 5 subsquare, posterior lobe blunt apically; apical half of cerci slender and pointed at apex; surstylus apically narrowed and blunt; pregonite short, slightly bent at apex; basiphallus longer than postgonite and distiphallus long and plate-like.

Female. Frons widened anteriorly, about 1/3 head width at narrowest point; 6−7 inclinate frontal setae; 2 strong proclinate orbital setae and 1 small outclinate prevertical seta; inner vertical seta about 2/3 eye height, twice as long as outer vertical setae. Mid tibia with 2 anterodorsal, 2 posterodorsal setae. Abdomen ovate, reddish yellow, a triangular black marking on posterior 3/4 of tergite 3, 1/2 of tergite 4 and 1/4 of tergite 5; grayish white pruinosity on anterior 1/4−1/2 of tergite 3, 1/2−2/3 of tergite 4, and 3/4−4/5 of tergite 5. Other characters as in male.

Type material. Holotype male, INDONESIA, Suranadi , 100 m, Lombok, 18−21.xii.1973, H. Kurahashi ( BLKU) . Paratypes. INDONESIA. 1 female, Beratan, 1000 m, Bali Is. , 15.xii.1973, H. Kurahashi . 14 males, 18 females, Suranadi, Sesaot and Sembella , 100−300m, Lombok , 18−22.xii.1973, H. Kurahashi & S. Shinonaga . 3 males, Wolowaru , 600 m, Flores, 20.xii.1973, H. Kurahashi . 2 males, Senaru , 750 m, Lombok I., 30.ix.2000, T. Tachi . 1 male, Pusuk Pass (monkey forest), 260 m, Lombok I., 1.x.2000, T. Yamauchi ( BLKU) .

Etymology. Specific name is dedicated to Dr. H. Kurahashi for his contribution to systematics of Diptera .

Distribution. Indonesia (Bali, Flores, Lombok).

Remarks. This new species closely resembles D. longipes , but differs from it in having black hairs on thoracic pleura and abdominal sternite 1, outer and inner black vittae merged on postsutural scutum, abdominal tergites each with a large triangular black marking.