Genus Apodacra Macquart, 1854

Apodacra Macquart, 1854: 425 . Type species: Apodacra seriemaculata Macquart, 1854, by monotypy.

Apodacra: Nandi, 2002: 77 (review of Hindustan species); Povolný & Verves, 1997: 80 (review); Rohdendorf, 1925: 63 (review); 1930: 12, 18 (revision); 1970: 627 (in key), 629 (key to species); Rohdendorf & Verves, 1980: 462 (in key); Séguy, 1941: 251 (review of West Palaearctic species); Townsend, 1938: 99 (diagnose); Venturi, 1960: 34 (review of European species); Verves, 1986: 68 (catalog); 1990: 538 (key to East Palaearctic species); Verves et al., 2015: 265 (review); Zerova et al., 2006: 88 (in key), 95 (key to Ukrainian species).

Parapodacra Rohdendorf, 1925: 68 (as subgenus of Apodacra Macquart, 1854). Type species: Apodacra chrysocephala Rohdendorf, 1925, by designation of Townsend, 1935: 203.

Diagnosis. Small, rarely medium-sized (3.0– 6.5 mm) bright colored flies. Frons and face broad, vibrissal angle placed at oral margin, head in profile angular; posterior border of head distinctly shortened; orb 1–2+2–6, strong; postpedicel 3–5× as long as pedicel.

D i s t r i b u t i o n a n d d i v e r s i t y. 16 species distributed in Palaearctic, Oriental and Afrotropical Regions.

Key to species

1. All abdominal tergites shining black, with narrow stripe of light dusting near fore margin (fig. 7, f). Oral setae black, anterior part of gena with black setulae (figs 7, b–c). 4.5 mm ..................... A. melanura sp. n.

— Abdominal tergites not entirely black, with shining black spots in posterior half (figs 1, b; 3, g; 4, b; 5, f; 6, f; 8, g; 9, b; 10, f; 11, b). ...................................................................................................................................2

2. Apart from a vi, other oral setae absent (figs 1, c–d; 2, c–d; 5, b–c; 10, b–c; 11, c–d). Gena with yellow setae. .......................................................................................................................................................................3

— Apart from vi, at least one black oral seta present (figs 3, b–c; 4, c–d; 6, b–c; 8, b–c; 9, c–d). ..................5

3. Arista widened in basal 0.4–0.5 (figs 1, c; 2, c). Facials strongly narrower than frons (figs 1, d; 2, d–e). {: wing with cell r 2+3 entirely, cells r 1, r 4+5 and dm partly fumose (fig. 1, f), fore 5 th tarsomere with long d (fig. 1, e). 4.5–6.5 mm. ............................................................................ A. chrysocephala Rohdendorf, 1925

— Arista widened in basal 0.6–0.8 (figs 5, b; 11, b–c). Facials almost as wide as frons (figs 5, c; 10, c; 11, d). {: wing hyaline, without darkened areas (figs 5, a; 10, f; 11, e). ....................................................................4

4. The distance between median spot of 4 th abdominal tergite and each lateral stripe more than diameter of median spot; median spot of 5 th tegite much shorter than its lateral spots (fig. 5, f). {: hind 1 st tarsomere widened, with ventral ctenidium formed by short spine-like setae (fig. 5, e). 5.0 mm. ............................... ................................................................................................................................................... A. firanensis sp. n.

— The distance between median spot of 4 th abdominal tergite and each lateral stripes much less than diameter of median spot; all spots of 5 th tergite equal in size (fig. 10, f). {: Hind 1 st tarsomere without ctenidium (fig. 10, a). 4.0– 6.5 mm. ............................................................. A. seriemaculata Macquart, 1854

5. Some black setae present above vi (figs 8, b–c; 9, c–d). {: Fore 1 st –4 th tarsomeres with numerous elongate, erect d (fig. 8, e). 4.5–6.5 mm. .............................................................................. A. pulchra Egger, 1861

— No black setae above vi (figs 3, b–c; 4,c–d). {: Fore tarsus without long erect setae, normal setae only (figs 3, a; 6, a).........................................................................................................................................................6

6. Gena with black setae (figs 6, b–c). {: Hind 1 st tarsomere not widened, without ventral ctenidium (fig. 6 a). 4.5 mm ..................................................................................................................... A. idiopatica sp. n.

— Gena with yellow setae (figs 3, b; 4, c). {: Hind 1 st tarsomere widened, with ventral ctenidium (fig. 3, e). .....7

7. Ground color of abdomen silver-white (figs 3, g; 4, b). 4.5–6.5 mm. ............... A. dispar Villeneuve, 1916

— Ground color of abdomen orange-yellow. 5.0 mm. ..................... A. radchenkoi Verves et Khrokalo, 2015