Key to males of the Bengalia spinifemorata species-group

1. ST5 flap broad, semicircular, with a straight posterior margin, latter with a slight notch in the middle (Fig. 59). Bacilliform sclerite process forming a massive hook (Fig. 54). Semicircular sclerotisation apically with triangular expansion, its apical margin strongly concave (Figs. 56–58). Veil process curved and distally dentate and slightly flattened (Figs. 57, 58)................................................................................... 6. Bengalia wangariae (Lehrer)

- ST5 flap shaped otherwise, with a broad, shallow or deep excavation in the hind margin. Bacilliform sclerite process much smaller. Semicircular sclerotisation apically expanded, or narrow and not apically expanded. Veil process almost straight, rounded in cross-section, and not expanded distally, or curved, distally expanded and flattened........................ 2

2. ST5 flap with a shallow excavation in posterior margin (Figs. 8, 33). Bacilliform sclerite process moderate in size (Figs. 2, 21). Distal end of semicircular sclerotisation expanded into a triangle with a concave anterior margin (Figs. 3, 4, 29, 30). Distal end of veil process rounded in cross-section, not broad and flattened, sometimes with small subapical processes (Figs. 6, 23–28). No narrow backward extension of the hypophallic lobes, as seen in ventral view (Figs. 6, 7, 31)....................... 3

- ST5 flap with a deep excavation in posterior margin (Figs. 18, 42, 50). Bacilliform sclerite process forming a very low protuberance (Figs. 12, 36, 45). Distal end of semicircular sclerotisation narrow, not expanded (Figs. 16, 39, 40, 48). Distal end of veil process expanded and flattened (Figs. 16, 39, 48). Posterior half of the hypophallic lobe half as wide as the anterior part as seen in ventral view (Figs. 40, 49)....................................................................... 4

3. Veil large and horizontal, with a few radiating ribs present, distal edge with 8–10 serrations (Figs. 3–7). Two minute cones on underside of dorsalmost part of the semicircular sclerotisation (Figs. 3, upper pink arrow; 5, pink arrow).............................................................................................1. Bengalia akamanga (Lehrer)

- Veil smaller and vertical, consisting of upper and lower parts, upper part with radiating ribs as seen from front (Figs. 28, 29), lower part “hanging” down in front of apex of semicircular sclerotisation (Figs. 23, 29, 30). Strongly developed, ventrally directed flat knob at the dorsalmost part of the semicircular sclerotisation (Figs. 23, 31, 32, pink arrows).......................................................................................... 3. Bengalia seniorwhitei (Lehrer)

4. ST5 flap deeply sunk in the main part of ST5, its hind margin at the side of the excavation, i.e., the tips of the “horns”, not reaching back to level of the hind margin of ST5 proper (Fig. 50). Surstylus with parallel upper and lower edges in lateral view (Fig. 45), slightly concave on inside (Fig. 46). Veil relatively small, without anterior rib (Figs. 47, 48). Tip of beak at level of junction of veil and veil process in lateral view of distiphallus (Fig. 47)............ 5. Bengalia spinifemorata Villeneuve

- ST5 flap not deeply sunk in the main part of ST5, the hind margin at the side of the excavation, i.e., the tips of the “horns”, projecting backwards well beyond the hind margin ST5 proper (Figs.18, 42). Surstylus slightly broadening distad, with a conspicuous long and low bulge middorsally (Figs. 12, 36), very strongly concave on inside (Figs. 13, 37). Veil large, with anterior rib (Figs. 15, 38). Tip of beak well behind level of junction of veil and veil process (Figs 14, 38)........................ 5

5. Excavation in hind margin of ST5 flap V-shaped, the projections or “horns” being straight or even slightly convex on inside (Fig. 18). The dentate process of the distiphallus gradually tapering distally (Fig. 17)....... 2. Bengalia racovitzai (Lehrer)

- Excavation in hind margin of ST5 flap U-shaped, the projections or “horns” being concave on inside (Fig. 42). The dentate process of the distiphallus narrows subapically and widens out again apically, apical area with broad pale part ventrally and distally (Fig. 41)................................................................ 4. Bengalia smarti (Lehrer)