Dexia alticola 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 : 11-13

Dexia alticola Zhang et Shima , sp. nov.

Figs. 1−4

Diagnosis. Antenna reddish yellow except dark brown on distal half of 1st flagellomere; 3 presutural and 3 postsutural dorsocentral setae; 2 supra-alar setae; 2 katepisternal setae; femora reddish brown.

Description. Body length. 7.0− 9.3 mm.

Male. Head with grayish white pruinosity on fronto-orbital plate and parafacial; frontal vitta brownish black; lunule brown; gena reddish brown. Antenna reddish yellow except brownish black on apical half of 1st flagellomore. Palpus and labella reddish yellow. Frons 1/6−1/8 head width, frontal vitta slightly wider than fronto-orbital plate, parafacial bare, about 2.5 times as wide as 1st flagellomere; facial carina longer than 1st flagellomere and nearly straight in lateral view; gena 0.43−0.46 times as wide as eye height, lower margin of face protruding forward. Inner vertical seta 0.28−0.31 times as long as eye height, shorter than ocellar seta; ocellar seta about as long as upper frontal setae; 8−10 inclinate frontal setae; vibrissa inserted above lower margin of face. Antenna falling short of lower margin of face by about length of 1st flagellomere, the latter about 3 times as long as pedicel; total width of arista including plumosity about 3 times as wide as 1st flagellomere. Palpus about as long as prementum, longer than 1st flagellomere.

Thorax black in ground color, with yellowish gray pruinosity and 4 brown-black longitudinal vittae on dorsum, outer vitta widened posteriorly, about 3 times as wide as inner vitta, an inner vitta 1/4−1/5 as wide as pruinose portion between inner and outer vittae on prescutural scutum, scutellum reddish yellow at apex; pleura with grayish pruinosity. Proepisternum bare; 1−2 presutural and 1−2 postsutural acrostichal setae; 3 pre- and 3 postsutural dorsocentral setae; 2 postsutural intra-alar setae; 2 supra-alar setae; 2 katepisternal setae; apical scutellar setae longer than scutellum and shorter than subapical scutellar setae. Wing brownish, tegula usually reddish yellow or brown; basicosta black; costal spine slightly longer than crossvein r–m; relative lengths of 2nd, 3rd and 4th costal sectors approximately 3:6:4; vein M from dm-cu crossvein to its bend 2.0−2.5 times distance between the bend and wing margin, sometimes with a short appendix. Halter reddish yellow. Calypters yellowish, lower calypter with long fringe on outer margin. Legs yellow to reddish brown on femora and reddish yellow on tibiae, mid and hind tibiae darkened at apex; mid tibia with 2 posterodorsal setae; hind tibia slightly flattened at base, with 3−5 anterodorsal, 2 posterodorsal and 2 ventral (upper one fine) setae.

Abdomen long ovate, translucent yellow, with a wide black median longitudinal vitta (about 1/3 width of tergite 4), and dark brown posterior margins of syntergite 1+2 and tergite 3, posterior 1/5−1/3 of tergite 4 and posterior 1/2 of tergite 5; dorsum with grayish white pruinosity on anterior 1/3 of tergite 3, anterior 1/3−1/2 of tergite 4, anterior 1/2 of tergite 5. Abdominal syntergite 1+2 with 1 lateral marginal seta, without median marginal setae; tergite 3 with 2 pairs of median discal, 1 pair of median marginal and 1−3 lateral marginal setae; tergite 4 with 2 pairs of median discal and a row of marginal setae; tergite 5 with a row of discal and marginal setae. Male terminalia. Cerci slender on distal half, surstylus pointed apically; pregonite short and bent posteriorly; postgonite slightly shorter than basiphallus; distiphallus long and thin, with some small spinules on ventral membranous surface.

Female. Frons 1/3−2/5 head width, frontal vitta narrower than fronto-orbital plate, 5 inclinate frontal setae; 1 outwardly directed prevertical and 2−3 strong proclinate orbital setae; outer vertical seta about 1/2 as long as inner vertical seta. Mid tibia with 2 anterodorsal, 2 posterodorsal and 1 ventral seta. Abdomen black, with grayish white pruinosity on anterior 1/2−1/4 of each tergite, tergites 3 and 4 each with or without a pair of fine median discal setae; tergite 5 without discal setae. Other characters are almost as in male.

Type material. Holotype male, CHINA, Xueshangou, 3400 m, Jiuzhaigou , Sichuan, 31.vii.1993, H. Shima ( IZCAS) . Paratypes. CHINA. Gansu: 1 female, Qilian, Xishui , 23.viii.2006 ( SNU) . 21 males, 3 females, Datulugou, 2300–2350 m, Yongdeng , 20.vii.2009, C. Fu & Y.-Y Zhou ( SNU) . Qinghai: 1 male, Xiaosumeng, 3750−4100 m, Yushu , 6.vii.1964, S.-Y. Wang . 2 males, Gelong, 3700 m, Yushu county , 11−12.vii.1964, S.-Y. Wang ( IZCAS) . 1 male, Yushu , 29.vi.1959, Z.-Z. Chen ( SEMC) . 2 males, Beishan Forest Park, Huzhu , 2500–2900 m, 23.vii.2009, C. Fu . 2 males, 2 females, Tianchi , 2400–2600 m, 27– 28.vii.2009, Mengda, Xunhua, Z. Zhao & C. Fu ( SNU) . Sichuan: 2 males, 3 females, Erdaogou vil., 3400 m, Nanping , 2.vii.1993, H. Shima ( BLKU) . 11 males, Xueshangou, 3400 m, Jiuzhaigou , 31.vii.1993, H. Shima ( BLKU) . 32 males, 3 females, Huasheng , 3100 m, Songpan County, 8.viii.1993, H. Shima ( BLKU) . 2 males, Mt. Paoma, 2600−3500 m, Kangding , 18.viii.1993, X. Lin ( BLKU) . 2 males, 1 female, Daoban, 2400 m, Jiuzhaigou , 3.viii.1993, H. Shima ( BLKU) . 5 males, 22 females, Yulin, 3000 m, Kangding , 20.viii.1993, H. Shima ( BLKU) . 1 male, Xingduqiao, 3700 m, Kangding , 22.viii.1993, H. Shima ( BLKU) . 2 males, 6 females, Zheduo Shan, 3000−4000 m, Kangding , 19−24.viii.1993, H. Shima, X. Lin, W.-X. Zhang ( BLKU) . 1 male, 3100 m, 4.viii.1983, H. Cai ( IZCAS) . 2 males, Kangding , 14.vii.2005, L. Chang, J.-Y.Liu . 2 males, 2 females, Kangding , 7.vii.2006, C.-T. Zhang, L.-Y. Feng ( SNU) . 1 female, Tagong Grassland, Kangding , 29.vii.2004, Y.-F. Tong ( SNU) . 15 males, 2 females, Gongga Shan, Yanzigou, 2000−2800 m, Luding , 12.vii.2005, L. Chang, J.-Y. Liu, H. Ao ; 12 males, 5 females, same locality as previous, 17.vii.2006, C.-T. Zhang, J.-Y. Liu, L.-Y. Feng ( SNU) . 26 males, 17 females, Laoyulin to Yajiageng, 3000−4000 m, Kangding , 6.vii.2006, C.-T. Zhang, J.-Y. Liu, L.-Y. Feng ( SNU) . 1 male, Lubuzaka, 3800−3900 m, Daocheng , 9.vii.2006, C.-T. Zhang ( SNU) . 9 males, 5 females, Geka to Echu Shan, 2260−4100 m, Daocheng , 14.vii.2006, C.-T. Zhang, J.-Y. Liu, L.-Y. Feng ( SNU) . 4 males, Chengtu , 5000ʹ, 6−16.viii.1933, D.C. Graham ; 1 male, Suifo–Kiating , 13.vi.1929 ( USNM) . Xizang (= Tibet): 1 male, Jiangda , 3800 m, 27.vii.1975, Z. Wang ( IZCAS) . 3 males, Médong , 31.vii.1983, G.-T. Jin ( SEMC) . 4 males, Lang County, 5.vii.1977, J.-Y. Wu . 1 female, Beibeng , 28.vii.1977, J.- Y. Wu . 4 males, Linzi , 9.vii.1979, J.-Y. Wu . 2 males, 1 female, Milin , 2.viii.1980, 11.vii.1984, J.-Y. Wu, Y.-H. Zhong ( SEMC) . 1 female, Paizhen, 3000 m, Milin , 7.viii.2003, M.-F. Wang ( SNU) . 1 male, Yin –kuan– Tsai , 13000−15000 ft, 25.vii.1930, D.C. Graham ( USNM) . Yunnan: 1 male, Wuliang Shan, 2300 m, Jingdong, Simao , 24.viii.1990, L. Su ( BLKU) . 1 male, Baoshan , Mt. NE Shan, 1200−1800 m, Keleinofsky, 28.v.1955 ( IZCAS) . 1 male, Adong, 2700 m, Deqin , 5.ix.1981, X.-Z. Zhang ( IZCAS) . 2 males, 1 female, Napahai, 3300 m, Zhongdian (= Shangri-La), 1.vii.2006, M.-F. Wang . 1 male, 13 females, Geze, Shangri-la , 3200 m, 18.viii.2010, C.-T. Zhang, Q. Wang ( SNU) . 1 female, Gaoligong Shan , 2500 m, 17.vii.2008, X.-D. Fei ( SNU) . 1 female, Baima Xueshan , 4200 m, 26.vii.2008, S.-C. Bai ( SNU) . 1 male, Wuliang Shan, 2800 m, Jingdong, Simao , 9.vi.2010, C. FU ( SNU) . 8 males, Shika Xueshan, 3200 m, Shangri-la , 30.vi.2010, C. Fu & Y.-Y. Zhou ( SNU) . 1 female, Shigu Town, 1800 m, Lijiang , 20.viii.2010, Q. Wang ( SNU) .

Etymology. The specific epithet refers to the collection of this species at high altitude, “alta” (altus) from the Latin for high place and “cola” for dweller.

Distribution. China (Gansu, Qinghai, Sichuan, Xizang, Yunnan).

Remarks. This species is mainly found at high altitudes (2400−4000 m) in southwest China. It is similar to D. violovitshi , but differs from it in having the apical half of 1st flagellomere dark brown, lunule brown, prosternum 2.0−2.5 times as long as wide, and tergite 5 black on posterior half.