Isopexopsis Sun and Zhao, 1994 , p. 480

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 : 1649

Isopexopsis Sun and Zhao, 1994, p. 480 , syn. n.

Type species. Isopexopsis parafacialis Sun and Zhao, 1994 (= Pujolina leucaniae Chao and Jin, 1984 ), by original designation.

For other synonyms see Crosskey 1977: 672–673; Cantrell and Crosskey 1989: 776; O’Hara and Cerretti 2016: 128–129.

Diagnosis

Male and female. Head dichoptic; eyes bare; ocellar setae absent; 2 reclinate orbital setae in male and female; 2 proclinate orbital setae in female; antenna with postpedicel at least 3 times as long as pedicel; arista bare.

Thorax black in ground colour, scutellum sometimes reddish on apical portion; 4 or 5 postpronotal setae, 3 basal setae set nearly in a straight line; 3 presutural and 3 postsutural acrostichal setae; 3 presutural and 4 postsutural dorsocentral setae; 1 presutural and 3 postsutural intra-alar setae; 3 postsutural supra-alar setae, 1st seta longer and stronger than 1st postsutural intra-alar and notopleural setae; prosternum usually haired on both side, rarely bare. Wing usually hyaline, rarely strongly darkened on basal area; basicosta black; 2nd costal sector bare below; wing veins bare except for base of vein R 4+5; cell r 4+5 open. Legs black in ground colour, tibiae sometimes reddish yellow, mid-tibia with 1–4 anterodorsal setae, pulvilli pale yellowish.

Abdomen with dorsal excavation of syntergite 1 + 2 extending to posterior margin; 4th tergite with a row of marginal setae; 5th tergite with rows of discal and marginal setae mixed with erect strong hairs; median discal setae indistinct on 3rd and 4th tergites; male 5th sternite with long inverted U-shaped posteromedian cleft, on almost posterior 5/6 of tergite.

Male terminalia. Sixth abdominal tergite reduced to 2 small hemitergites, without hairs; cerci in dorsal view narrowed from base to apex, apical 1/3 narrowly separated from each other; surstylus in lateral view shorter than cerci; epiphallus inclined posteriorly, low in height and rather long in length; distiphallus flat, without medio-ventral expansion.

Female terminalia. Sixth tergite separated medially or entirely at least on basal 1/2; 7th tergite broadly separated into hemitergites; 7th sternite longer than 7th tergite, posteromedian portion well narrowed and expanded apically.

Remarks

The genus Blepharella appears to be similar to Takanomyia except for the hairy eyes, no ocellar setae, spinous setae simultaneously on the apical parts of the scutellum and apical portions of 3rd–5th abdominal tergites, and the facial ridge always with downcurved setae. The male terminalia of both species are similar in having the posteriorly directed low epiphallus and lacking medioventral expansion of the distiphallus. Stireman et al. (2019) noted that Blepharella is the sister to a monophyletic group Pales Robineau-Desvoidy + ( Palia Curran, 1927 + Datvia Richter, 1972 ) in their molecular-based phylogeny, though they did not include Takanomyia in their analysis. In the external morphology Pales , Palia and Datvia differ from Blepharella in having only 1 reclinate orbital seta, and the former two also differ in having hairy eyes and strong downcurved setae on the facial ridge.