Key to males of Mberu species

1 Base of femur I with anterior bush-like comb of setae (Figs 6D, 7B); It1 longer than remaining tarsomeres combined (Fig. 5D); femur II with ventral surface bare, except for anteroventral row of setae, decreasing in length towards apex, and 1 av long and sometimes sinuous near apex (Figs 4D, 5E) … pepocatu group................................................ 2

- Base of femur I without conspicuous differentiated setae; It1 shorter than remaining tarsomeres combined; ventral surface of femur II completely bare............................................................................... 7

2 Wing venation without modifications and spurious veins, dm-m straight, M 4 complete, ending at wing margin (Figs 1F, 4F, 6F)................................................................................................ 3

- Wing venation with modifications well defined, reticulated, with short spurious veins arising from R 4+5, M 1, dm-m or M 4; dm-m distorted, S-shaped; M 4 incomplete, not reaching wing margin (if reaching margin, just branch, not main vein) (Figs 3F, 5G, 7D)................................................................................................ 5

3 Eyes touching on face (Fig. 6B); wing vein M 1 with distinct flexion S-shaped beyond crossvein dm-m, R 4+5 and M 1 parallel apically to costa (Fig. 6F); femur II and tibia II without conspicuous row of setae (Fig. 6E) [Brazil: Goiás and Mato Grosso do Sul]............................................................................... Mberu lopesi sp. nov.

- Eyes not touching on face (Figs 1B, 4B); wing vein M 1 slightly concave at anterior margin, without distinct flexion, R 4+5 and M 1 beyond crossvein dm-m converging apically to costa (Figs 1F, 4F); femur II with row of ad setae, tibia II with row of anterior setae (Figs 1E, 3E, 7C)................................................................................ 4

4 Lower surface of occiput with ventral pocl s sparse and straight, as long as vt s, and some sparse and straight white ocp s, increasing in size ventrally, the ventralmost 1.3 times as long as ventral pocl s (Fig. 1B, C); setae on anterior surface of coxa I shorter than width of coxa (Fig. 1D); wing membrane light brown, slightly darker along anterior margin and at apex (Fig. 1F) [Brazil: Goiás].................................................................... Mberu altamiro sp. nov.

- Lower surface of occiput with ventral pocl s dense and sinuous, two times as long as oc s, and numerous dense and sinuous white ocp s, increasing in size ventrally, the ventralmost as long as lower pocl s (Fig. 4B, C); setae on anterior surface of coxa I longer than width of coxa (Fig. 4C); wing membrane completely hyaline (Fig. 4F) [Brazil: Distrito Federal and Goiás]...................................................................................... Mberu ericae sp. nov .

5 Wing venation slightly modified, with short spurious veins arising from M 1, dm-m and M 4; R 4 +5 without spurious veins; M 4 ending in small brown spot at apex (Fig. 3F); It 1 not swollen at basal 1/3 [Brazil: Mato Grosso do Sul]................................................................................................ Mberu bodoquena sp. nov .

- Wing venation conspicuously modified, reticulated, with short spurious veins arising perpendicularly from R 4+5, M 1, dm-m and M 4 (Figs 5G, 7D); M 4 not ending in spot; It1 ventrally swollen at basal 1/3 (Fig. 5D)............................... 6

6 Wing membrane light brown, slightly darker along anterior margin, apex of R 4 +5 and M 1 slightly anastomosed, but not forming brownish spots at their apices (Fig. 7D) [Brazil: Minas Gerais]............... Mberu pepocatu Capellari & Amorim, 2011

- Wing membrane hyaline, apex of R 4 +5 and M 1 greatly anastomosed, with anastomoses forming brownish spots touching each other or nearly so (Fig. 5G) [Brazil: Distrito Federal, Goiás and Mato Grosso do Sul].............. Mberu jawara sp. nov .

7 Tibia III dorsally swollen on apical half and comb of posterior pale setae inclined to apex (Figs 12E, 18E); DSur (Figs 13D, 19D) irregularly shaped and robust, with curved ventral margins and truncated, rounded distal lobe; phallus with short dorsal projection near apex (Figs 13G, 19F)..................................................................... 8

- Tibia III not conspicuously swollen and without comb of setae; DSur narrow and elongated, with straight ventral margins (Figs 9D, 11D, 15D, 17D, 21D); phallus without dorsal projection near apex (Figs 9G, 11G, 17F, 21E)...................... 9

8 Coxa I with conspicuous posterior hook-shaped projection (Fig. 12C); It1 with distinct row of spine-like setae (Fig. 12D) [Brazil: Mato Grosso do Sul and Rio Grande do Sul; Paraguay: Coronel Oviedo; Argentina: Corrientes]................................................................................................... Mberu lamasi sp. nov.

- Coxa I without conspicuous projection (Fig. 18C); It1 without modified setae (Fig. 18D) [Brazil: Santa Catarina and Rio Grande do Sul]..................................................................... Mberu soaresi sp. nov .

9 Eyes touching on face (Figs 14B, 20B); MEp branched at apex (Figs 15G, 21H).................................. 10

- Eyes not touching on face (Figs 8B, 10C, 12B, 16B, 18B); MEp not branched at apex (Figs 9F, 11E, 13E)............. 11

10 Body length about 2 mm; postpedicel about 2.4 times as long as basal width (Fig. 20B, C); male hypopygium large, elongate, reaching forward to abdominal segment 2 (Fig. 21A, B) [Brazil: Goiás]...................... Mberu takwajasu sp. nov.

- Body length less than 1.6 mm; postpedicel about 1.6 times as long as basal width (Fig. 14B, C); male hypopygium stout, not elongate, reaching forward to abdominal segment 4 (Fig. 15A) [Brazil: Mato Grosso do Sul]... Mberu murtiniensis sp. nov.

11 DSur about 3.7 times as long as high, curved near apex (Fig. 17D), conspicuously projecting beyond VSur (Fig. 17A, B) [Brazil: São Paulo]................................................................. Mberu periotoi sp. nov.

- DSur about 2.7–3.0 times as long as high, straight, not conspicuously projecting beyond VSur (Figs 9A, B, D; 11A, B, D).. .................................................................................................. 12

12 Legs completely yellow (Fig. 8A); MEp stout, about 2.5 times narrower than VSur, with rough dorsal face (Fig. 9C, F) [Brazil: Rio Grande do Sul]................................................................ Mberu amorimi sp. nov.

- Legs mostly dark brown (Fig. 10A); MEp narrow, about 4.5 times narrower than VSur, with smooth dorsal face (Fig. 11C, E) [Brazil: Goiás and São Paulo].......................................................... Mberu britoi sp. nov .