Blepharella vietnamensis Shima and Tachi, 2025

Shima, Hiroshi, Tachi, Takuji & Zhang, Wenxia, 2025, The genus Blepharella Macquart (Diptera: Tachinidae) from the Oriental Region, Journal of Natural History 59 (21 - 24), pp. 1647-1687 : 1680-1682

Blepharella vietnamensis Shima and Tachi sp. n.

( Figure 11 )

Diagnosis

A large greyish goniine; head with whitish pruinosity; vertex about 1/4 of head width; gena about 1/3 of eye height; upper occiput without black setulae behind postocular setae; palpus yellowish; thorax with whitish grey pruinosity, 4 longitudinal vittae, outer vittae broad and inner ones narrow; apical scutellar setae very fine, hair-like, crossed suberectly; 3 katepisternal setae; wing hyaline, slightly darkened basally; tibiae black; hind tibia with a very closely set comb-like row of anterodorsal setae, without a submedian strong seta; male claws and pulvilli shorter than 5th tarsomeres; male 4th abdominal venter with dense fine and broad sexual hair patches.

Description

Holotype male, VIETNAM, Son La /Prov., E of Ban / Song, Dao Cao Pha / 420 m, 7.vi.1999 / Col. H. Kurahashi ( BLKU).

Male. Head with whitish pruinosity, fronto-orbital plate and upper postorbit weakly pale yellowish; occiput with whitish pruinosity; antenna brown-black; palpus reddish yellow, weakly darkened basally. Vertex about 1/4 of head width; frontal vitta widened anteriorly, about 5/8 of fronto-orbital plate at middle; parafacial narrowed below, about 3/5 width of postpedicel at mid-height; gena about 1/3 of eye height; face weakly excavated, lower margin only slightly curved forward beyond vibrissal base; occiput flattened. Inner vertical seta about 3/5 of eye height; outer vertical seta indistinct; 2 subequally long reclinate orbital setae, about 2/3 as long as inner vertical seta; 10–11 frontal setae; fronto-orbital plate with dense fine short hairs, not descending below lowest frontal seta; facial ridge with long lower and short upper setae on lower 1/3; vibrissa inserted above lower margin of face by about 1/2 length of pedicel; genal dilation occupying almost 1/10 of gena, with dense short hairs mixed with some stronger hairs on anteroventral portion; occiput with 1–2 rows of fine short black hairs on lower 1/2, without such hairs on upper 1/2. Antenna falling short of lower margin of face by about length of pedicel; postpedicel about 2.7 times as long as pedicel; arista thickened on basal 1/3, 2nd aristomere nearly as long as wide. Palpus clavate, about as long as pedicel.

Thorax black in ground colour, apical portion of scutellum narrowly reddish, with rather dense greyish white pruinosity, denser on postpronotal area and lateral portion of presutural scutum, pleura with rather dense greyish pruinosity; broad lateral and narrow inner vittae distinct on scutum, lateral vitta almost 3 times as wide as inner vitta. Hairs on dorsum dense fine short and erect; lateral scutellar setae double, posterior seta stronger than anterior one and subequal in length to scutellum; subapical scutellar seta 1.3 times as long as scutellum; distance between subapical scutellar setae about 1/2 that between subapical and basal setae of corresponding side; 3 katepisternal setae; prosternum with several strong hairs on each side. Wing hyaline; lower calypter whitish with pale yellowish margin; relative lengths of costal sectors 2nd, 3rd and 4th approximately 2.5:3:2; length of vein M1 from dm-cu crossvein to bend about 2 times distance between bend and wing margin; crossvein dm-cu weakly sinuate, about 2 times length of last section of vein CuA1. Legs black, pulvilli pale brownish; mid-tibia with 2 anterodorsal setae; hind tibia with a closely set comb-like row of anterodorsal setae, no stronger seta among them; claws and pulvilli slightly shorter than 5th tarsomeres.

Abdomen black in ground colour, dorsa with rather thin pale yellowish white pruinosity on anterior 3/5 of 3rd tergite, anterior 2/3 of 4th and anterior 4/5 of 5th tergites; venter with rather thin whitish pruinosity on anterior margin and anteromedian portion of syntergite 1 + 2 and 3rd tergite, narrow anteromedian portion of 4th tergite and almost anterior 3/4 of 5th tergite. Hairs on dorsum of 3rd and 4th tergites short recumbent, long and erect on 5th tergite; venter of 4th tergite with dense short and recumbent sexual hair patches on almost entire venter except pruinose portion; median marginal setae indistinct on syntergite 1 + 2 and 3rd tergite; median discal setae absent on 3rd and 4th tergites; 5th tergite with long erect and dense hairs mixed with rows of discal and marginal setae on posterior portion.

Male terminalia. Sixth tergite very weak semicircular hemitergite, without hairs; syntergosternite 7 + 8 very short; cerci in lateral view evenly narrowed to apex, apical portion roundly projected upward, in dorsal view evenly narrowed apically, apical 1/5 well separated; surstylus in lateral view narrowed posteriorly and weakly pointed at apex, narrower than cerci at mid-point; dorsal arms hypandrium connected with each other; pregonite with 3–4 hairs on posterior margin; postgonite pointed at apex, without hairs; epiphallus short and inclined posteriorly, on dorsodistal margin of basiphallus; distiphallus with dorsal sclerite narrow and long, about 2 times as long as ventral sclerite.

Female. Unknown. Body length: ca. 12.8 mm.

Host. Unknown.

Etymology

The specific name is taken from the country name of the type locality for this species, Vietnam .

Distribution

Vietnam (Son La Prov.).

Remarks

Despite the differences in general appearance, such as large size and broadly whitish pruinose body, the male terminalia of this species are very similar to those of B. kinabalensis Shima and Tachi sp. n.; the cerci with dorsally curved apex, dorsal arms of hypandrium fused with each other and distiphallus with dorsal sclerite very elongated. It is possible that this species is phylogenetically allied to B. kinabalensis .

Figures

Figure 11. Blepharella vietnamensis Shima and Tachi sp. n. (A) Adult male in lateral view. (B) Same in dorsal view. (C) Male genitalia in lateral view. (D) Epandrium, cerci and surstylus in later view. (E) Same in dorsal view. (F) Hypandrium, pre- and postgonite, epiphallus and aedeagus in lateral view. (G) Same in lateral view. Scale bars: 0.2 mm.