Dexia montana ( Baranov, 1932 )

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 : 56

Dexia montana ( Baranov, 1932)

Figs. 65−68

Sumatrodexia montana Baranov, 1932: 215 . — Sabrosky & Crosskey 1969: 52 (lectotype designation).

Dexia montana: Crosskey 1976: 179 (catalog). — Crosskey 1977: 603 (catalog).

Diagnosis. Thoracic scutum with 2 wide longitidual black vittae; tergites 4 and 5 wholly with grayish white pruinosity; legs reddish yellow; lower calypter with short fringe; surstylus bluntly rounded at apex.

Description. Body length. 11.3−13.0 mm.

Male. Head with dense pale yellowish pruinosity; antenna reddish yellow, with arista reddish brown; palpus reddish yellow. Frons 0.2−0.22 times as wide as head width; frontal vitta subequal in width to frontoorbital plate at middle; parafacial nearly parallel-sided, about twice as wide as 1st flagellomere at middle; face well concave, lower margin weakly warped forward; facial carina long, ridge pointed, apically widened; gena about 0.5 times as wide as eye height. Inner vertical seta about 1/2 as long as eye height, slightly shorter than ocellar seta; outer vertical seta hair-like; 7−8 frontal setae, lowest seta nearly level with base of antenna; fronto-orbital plate with a row of fine short hairs on median portion; gena with a few fine short hairs on lower portion; vibrissa inserted slightly above level of lower margin of face. Antenna falling short of lower margin of face by about 1/2 length of 1st flagellomere; 1st flagellomere about 5 times as long as pedicel; total width of arista including plumosity about 2.5 times as wide as 1st flagellomere. Prementum about 1/2 as long as eye height; palpus slightly shorter than 1st flagellomere.

Thorax black in ground color, postprontal lobe and apical portion of scutellum reddish, with dense grayish white pruinosity; with 2 broad longitudinal black vittae on dorsum, brownish pruinosity on median longitudinal portion between vittae and postero-median portion of postsutural scutum; anterior 2/3−3/4 of scutellum brownish black. Prosternum about twice as long as wide. Hairs black; proepisternum sometimes with fine black hairs; 3 postpronotal setae standing in a straight line; 1 presutural and 1−2 postsutural acrostichal setae; 2 presutural and 3 postsutural dorsocentral setae; 1−2 postsutural intra-alar setae; 1−2 supraalar setae; 2 katepisternal setae, katepisternum with 1−2 rows of sparse hairs in front of mid coxae. Wing hyaline, evenly tinged with pale brown; tegula black, basicosta reddish brown; lower calypter pale yellowish white. Costal spine absent; relative lengths of 2nd, 3rd and 4th costal sectors approximately 2:4:2.5; vein M from dm-cu crossvein to its bend about 2.3 times distance between the bend and wing margin. Lower calypter with short fringe on outer margin. Legs reddish yellow, distal portion of hind femur and basal and apical pritions of mid and hind tibiae slightly darkened; tarsi and claws black; pulvilli pale brownish. Hind leg longest, hind tibia sinuate near middle. Mid tibia with 2 posterodorsal setae; hind tibia with 1 anterodorsal, 1 posterodorsal and 1 ventral setae. Claw and pulvillus slightly shorter than tarsomere 5.

Abdomen reddish yellow in ground color, black on rather broad mid dorsal longitudinal portion of syntergite 1+2 to tergite 4, darkened on posterior 1/4 of tergites 3 and 4 and entire tergite 5; scutum with very thin whitish pruinosity on anteromedian margin of tergite 3 and entire tergite 4, and rather dense pruinosity on tergite 5, the pruinosity shifting in appearance with direction of light. Hairs fine short rather dense recumbent and black, erect and long on tergite 5; syntergite 1+2 with a lateral marginal seta, without median marginal setae; tergite 3 with 1 pair of fine median discal, 1 pair of strong median marginal and 1 lateral marginal setae; tergite 4 with 1 pair of strong median discal and a row of strong marginal setae; tergite 5 with a row of strong median discal and marginal setae, both rows very close to each other. Male terminalia. Cerci slender, pointed apically; surstylus long, wide and blunt at apex; pregonite short, with a protruding at middle; basiphallus about as long as postgonite.

Type material examined. Lectotype male of Sumatrodexia montana Baranov (by designation of Sabrosky & Crosskey 1969: 52), INDONESIA, Tijbodas [= Cibodas], 1400 m, xii.1927 . Paralectotype male, same data as lectotype ( USNM) .

Additional material examined. INDONESIA. 1 male, Tasari, Java, 6−8.iii.1915, Terry . 1 male, Java, Tijbodas [= Cibodas], 500 ft, xi.1905 ( BPBM) . 1 male, G. Gedeh, Java, ii.1913, Drescher ( ZMUA) .

Distribution. Indonesia (Java).

Remarks. This species resembles D. caldwelli , but differs from it in having 3 postpronotal setae, 2 katepisternal setae, and short fringe on outer margin of lower calypter.