Genus Cyaforma Wang

Cyaforma Wang, 1989 b: 358 .

Type-species: Cyaforma shenonica Wang, 1989, by original designation.

Diagnosis. This genus is characterized by having 2–3 pairs of frontal and 2 pairs of orbital setae; ocellar and paravertical setae very strong, subequal in length to outer vertical seta; postocellar seta small and weak; 3 pairs of scutellar setae, of which the apical pair crossed; 1–2 postsutural supra-alar, 1–2 postalar, 0–1 intrapostalar, 2–3 postpronotal setae present; dorsocentral seta aligned near or with anterior postsutural supra-alar seta. Facial carina well developed; oral margin and lower margin of parafacial not produced; antenna about 1/2 as long as face; arista short pubescent. Scutum black or yellow brown with medial or submedial black vittae. Wing dark brown to black in ground color, with hyaline area and/or hyaline spots; vein R 4+5 densely setulose dorsally to or beyond a level of dmm; pterostigma about 1/2 as long as cell c; lobe of cell cua rather short; r-m situated at or slightly distal to middle of cell dm. Fore femur with row of strong posteroventral setae; mid tibia with 2 strong apical spurs. Male genitalia with medial surstylus well developed, lateral surstylus nearly rounded at apex in profile. Oviscape nearly triangular, less than or equal in length to tergites 5–6, with large dorsoapical opening; eversible membrane with large ventral area of dark brown to black scales but without basal taenia; aculeus greatly expanded at base, strongly dorsally curved, apically tapered to a point and lacking preapical serrations; 3 pale, subspherical spermathecae present.

Biology. The biology of this genus was almost unknown before this study except that the collecting environment of C. shenonica was in a habitat where Pilea and graminaceous plants were the dominant vegetation, and C. macula found in grass of Pilea (Chen et al, 2021).

Distribution. With the addition of new species described below, four species of Cyaforma are now recognized. So far as known, the genus is restricted to the Palaearctic and Oriental region, all species occur in China.

Key to known species of Cyaforma Wang

1. Wing with at least 1 hyaline marginal indentation in cell r 1 distal to apex vein R 1 and 1 hyaline spot in cell dm (Fig. 1D; Fig. 2 AB); scutum predominantly yellow or yellow brown with 2 narrow submedian dark brown to black vittae (or predominantly dark brown to black, with single broad medial yellow vitta extended from anterior to posterior margin); scutum with 2 postsutural supra-alar setae....................................................................................... 2

- Wing largely black (Fig 4), with narrow hyaline area extending along posterior margin, cells r and dm entirely brown without hyaline spots; scutum predominantly dark brown to black, with 2 submedian yellow vittae extending from anterior margin to the front of a level with prescutellar acrostichal setae, which never extend to the posterior margin; scutum with only 1 postsutural supra-alar seta.................................................................... C. shenonica

2. Thorax with 3 postpronotal setae; wing with 1 hyaline spot in apical portion of cell r 2+3 (Fig. 1 D; Fig. 2 AB); occiput entirely yellow, without black or brown marks.................................................................... 3

- Thorax with 2 postpronotal setae; wing without hyaline spot in cell r 2+3 (Fig. 7 A, C); occiput with distinct black or dark brown marks................................................................................... C. tonkinensis

3. Wing with cell dm 3/4 brown and 1/4 pale brown, having 1 small unclear hyaline spot at apex cell dm (female, Fig. 1D)................................................................................... C. chayuica Chen, sp.nov

- Wing with cell dm almost wholly brown (pale brown area absent), having 1 large clear hyaline spot at apex cell dm (female, Fig. 2A); or wing with cell dm 1/2 brown and 1/2 pale brown, having 1 oblong unclear hyaline spot at apex cell dm (male, Fig. 2B)......................................................................................... C. macula