Dexia caldwelli Curran, 1927

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 : 19-21

Dexia caldwelli Curran, 1927

Figs. 13−16

Dexia caldwelli Curran, 1927: 8 . — Crosskey 1976: 178 (catalog). — Zhang & Shima 2004: 52 (Chinese Dexia ). — Zhang et al. 2004: 127. — Zhang et al. 2005: 305. — O’Hara et al. 2009: 28 (catalog).

Sumatrodexia incisuralis Baranov, 1932: 215 . — Sabrosky & Crosskey 1969: 52 (type material). — Zhang & Shima 2004: 52 (as syn. of D. caldwelli ). — Hao et al. 2008: 99 (list).

Dexilla caldwelli: Crosskey 1967: 106 .

Dexia incisuralis: Crosskey 1976: 179 .

Diagnosis. Large species; thoracic scutum with 1 pair of broad longitudinal black vittae; proepisternum hairy; abdominal tergites each with brownish markings on sides and with median discal setae; surstylus bluntly rounded apically.

Description. Body length. 11.3−20.0 mm.

Male. Head with pale yellowish pruinosity; antenna reddish yellow; palpus reddish yellow. Frons 0.16−0.17 times as wide as head width; frontal vitta 1.5−2.0 times as wide as fronto-orbital plate at middle; parafacial slightly widened below, 3−4 times as wide as 1st flagellomere at middle; facial carina long and high, ridge rather flattened, lower margin of face weakly protruded; gena 0.33−0.54 times as wide as eye height. Inner vertical setae 0.3−0.6 times as long as eye height; ocellar seta 1.2−1.4 times as long as inner vertical seta; 11−12 inclinate frontal setae, lowest seta nearly level with base of antenna; fronto-orbital plate with several fine short hairs; parafacial bare; gena with sparse short black hairs on lower and posterior 1/2; vibrissa inserted above level of lower margin of face by about length of pedicel; occiput with 1−2 rows of black hairs. Antenna falling short of lower margin of face by about length of pedicel and 1st flagellomere combined; 1st flagellomere 3−4 times as long as pedicel, total width of arista including plumosity 3−4 times as wide as 1st flagellomere. Prementum 4−5 times as long as wide; palpus slightly longer than antenna, shorter than prementum.

Thorax pale brown in ground color, reddish on postpronotal lobe and lateral portion of scutum; scutum with dense pale yellowish pruinosity, with 1 pair of broad longitudinal brownish black vittae, about twice as wide as pruinose portion between vittae; scutellum mostly brown except apical margin; pleura with thin pale yellowish white pruinosity. Anterior and posterior spiracles dark brown. Prosternum about 2.5 times as long as wide; proepisternum with several pale hairs; 2 postpronotal setae; 0−1 presutural and 0−1 postsutural acrostichal setae; 3 (seldom 2) presutural and 3 postsutural dorsocentral setae; 1−2 postsutural intra-alar setae, anterior one very fine; 3 supra-alar setae, middle one larger; 3 katepisternal setae, katepisternum with dense black hairs on upper half and black or yellowish brown hairs on lower half. Wing evenly tinged with pale brown; tegula and basicosta pale brown to brown; lower calypter pale brown. Costal spine absent; relative lengths of 2nd, 3rd and 4th costal sectors approximately 2:4−4.5:1.5−2; vein R 4+5 without setulae dorsally, with 2−5 fine setulae ventrally; vein M from dm-cu crossvein to its bend 3−4 times distance between the bend and wing margin, without or at most with very short appendix. Lower calypter with long fringe on outer margin. Legs reddish yellow, tarsi brown. Hind leg longer than others; hind tibia sinuate at basal 1/3. Mid tibia with 2 posterodorsal setae; hind tibia with 1−2 anterodorsal, 2 posterodorsal and 1−2 ventral setae. Claws and pulvilli very long.

Abdomen long, well extending beyond wing apex. Orange yellow except brown-black broad mid dorsal longitudinal portion of syntergite 1+2 to tergite 4, reddish brown on mid dorsal longitudinal portion of tergite 5; dorsum with thin pale yellowish white pruinosity on very narrow anterior portion of tergites 3 and 4 and entire 5, side and venter of tergite 5 with thin whitish pruinosity. Hairs black except on sternite 1 and venter of syntergite 1+2 which bear pale brownish or yellowish hairs, dense short fine and suberect, fine and erect on tergite 5; syntergite 1+2 with 1 short lateral marginal seta, without median marginal setae; tergite 3 with 0−2 pairs of discal, 1 pair of rather long median marginal and 1 short lateral marginal setae; tergite 4 with 2 pairs of median discal and a row of rather long marginal setae; tergite 5 with many discal and a row of marginal setae. Male terminalia. Posterior lobe of sternite 5 wide and bluntly rounded; surstylus long and wide, blunt apically; cerci narrow on apical half, pointed apically; pregonite short, slightly bent apically, with a protruding at middle; postgonite slightly longer than basiphallus.

Female. Frons about 1/3 head width; gena 0.50−0.57 times as wide as eye height. Fronto-orbital plate with dense hairs. Inner vertical setae crossed, about 3/5 eye height; outer vertical seta present, 1/2−1/3 as long as inner vertical seta; ocellar seta shorter than inner vertical seta; 2 subequally long proclinate orbital setae subequal in length to inner vertical seta; 1 outward directed prevertical seta shorter than ocellar seta; 6−8 inclinate frontal setae, lowest seta nearly level with base of pedicel. Tegula dark brown; vein R 4+5 with 3−4 setulae dorsally; lower calypter with short fringe. Abdomen short, more broadly darkened on mid dorsal longitudinal portion on each tergite and without median discal seta on tergite 3 to 5. Other characters almost same as in male.

Type material. Holotype male of Dexia caldwelli Curran , CHINA, Fujian, Nanping [Yen-ping] ( AMNH) (not examined) . Holotype male of Sumatrodexia incisularis Baranov (antennae and male terminalia missing), CHINA, Tatsienlu [= Kangding], Szetschwan [= Sichuan], v.1928 ( SMT) (examined) .

Additional material examined. BHUTAN. 1 female, Thimphu 2500 m, 12.vii.1993, T. Saigusa . CHINA. Fujian: 2 males, Siqian, 450−600 m, Guangze , 19.iv−2.v.1960, G.-T. Jin, X. Lin . 1 male, Xiyang, Yongan , 26.iv.1962, G.-T. Jin ( SEMC) . 1 male, Xingping , 11.viii.1980 . 1 female, Jianyang, Guilin, 270− 410 m. Guangdong: 1 female, Heishiding, Fengkai , 11.ix.1985, Z.-Y. Chen ( SYU) . Guangxi: 1 male, 1 female, Neicujiang, Huaping , 7.vi.1963, J. -K. Yang ( CAU) . 1 male, Baiyan, Longsheng , 21.vi.1963, Y.-S. Shi ( IZCAS) . Hainan: 1 male, Mt. Jianfengling , 14.ix.1983, M.-B. Gu ( SNU) . Jiangxi: 2 males, Tonggu , 16.ix.1982, Jiangxi Communist University ( SNU) . 1 male, Quannan , 650 m, 28.vii.2008, S.-C. Li ( SEMC) . Sichuan: 1 male, 9 miles SW of Tatsienlu , 8500−13000 ft, 25.vi.1923, D.C. Graham ( USNM) . Xizang: 1 male, Yigong , 2300 m, 30.vii.1978, F.-S. Li ( CAU) . 24 males, 5 females, Jilong, 2800 m, Jilong county , 27.vii.1975, X.-Z. Zhang and Z. Wang ( IZCAS) . 1 male, Tongmai , 1.ix.1977, G.-T. Jin ( SEMC) . Yunnan: 2 females, Menglun, Xishuangbanna , 1.viii.1959, 12.x.1959, Y.-Y. Zhang, L.-C. Zang . 1 female, Mt. Dawei, 2000 m, Pingbian , 23.vi.1956, K.-R. Huang. Zhejiang : 1 male, Tianmu Shan , 11.viii.1935 ( SYU) . INDIA. 2 males and 2 females identified as D. caldwelli by Crosskey ( BMNH) . MYANMAR. 1 male, S. Shan States Road 40 km, E. of Taunggyi , 25.ix–13.x.1934, Malaise ( SMNH) . NEPAL. 1 male, Thankot , 4.v.1980, Amnon Freidberg ( USNM) . 1 female, Godawari, Kathomanru , 24.v.1964, R. Kano . 1 female, Gokarna, 1400 m, Kathomanru , 30.viii.1988, T. Taoka . 1 female, Papun to Chanlung , 2100− 1250 m, 18.vii.1972, H. Shima ( BLKU) . THAILAND. 1 female, Chiengmai, Doi Suthop , 900 m, 14.xi.1957, J.L. Gressitt ( BPBM) . VIETNAM. 1 male, Cao Bang Prov., Mt. Pia Oac , 1320 m, 23−27.v.1999, H. Kurahashi ( BLKU) .

Distribution. Bhutan, China (Fujian, Guangdong, Guangxi, Hainan, Jiangxi, Sichuan, Xizang, Yunnan, Zhejiang), India (Himachal Pradesh, Punjab), Myanmar, Nepal, Thailand, Vietnam.

Remarks. This is a characteristic species and we consider that Sumatrodexia incisuralis is the same as this species based on identified specimens of D. caldwelli in BMNH. This species is rather similar to D. extendens , but differs from it in having 3 katepisternal setae, yellow legs, and abdominal tergites with median discal setae.