Key to the species of Sennius abbreviatus group

1 Integument of elytra completely black.................................................................... 2

- Integument of elytra red-orange to dark brown; if black, with maculae........................................... 6

2 Elytra with horizontal, wide and sparse strip of setae covering more than three quarters of anterior region (Fig. 75).............................................................................. S. rufomaculatus (Motschulsky, 1874) .

- Elytra with horizontal, narrow and dense strip of setae covering less than half of anterior region...................... 3

3 Elytra at 3rd strial interval with white setae on mesoapical region, except at extreme apex........................... 4

- Elytra at 3rd strial interval with white setae medially or absent.................................................. 5

4 Elytra with rounded patch of pale setae medially (Fig. 9).................................... S. bondari (Pic, 1929) .

- Elytra with white and gold setae forming horizontal strip medially (Fig. 47)... S. leucostauros Johnson & Kingsolver, 1973 .

5 Elytra with white setae forming zig zag strip (Fig. 55)...................................... S. lojaensis (Pic, 1933) .

- Elytra with white setae forming horizontal strip wider medially (Fig. 72)........ S. nappi Ribeiro-Costa & Reynaud, 1998 .

6 Integument of elytra without maculae.................................................................... 7

- Integument of elytra with maculae........................................................................ 9

7 Elytra with homogeneous golden and brown setae except at 1st and 2nd interstices with white setae (Fig. 29)............................................................................................. S. lawrencei Johnson, 1977 .

- Elytra with horizontal irregular or regular strip of pale setae on submedian region.................................. 8

8 Elytra with regular horizontal strip of pale setae on submedian region (Fig. 100)........................ S. vivi sp. nov.

- Elytra with patches forming an irregular horizontal strip of pale setae on submedian region (Fig. 21)...... S. flinte sp. nov.

9 Elytral setae evenly sparsely distributed or only dense patch at base of 3rd and 5th interstices.......................... 10

- Elytral setae unevenly distributed with strip or wide dense patch of pale setae at anterior region...................... 13

10 Base of 3rd and 5th interstices with dense patch of setae or integument with pale to dark brown maculae (Fig. 75)................................................................................ S. rufomaculatus (Motschulsky, 1874) .

- Base of 3rd and 5th interstices without dense patch of setae or integument with red-orange maculae..................... 11

11 Pronotum with denser setae laterally (Fig. 1)........................................... S. abbreviatus (Say, 1824) .

- Pronotum with evenly distributed setae.................................................................. 12

12 Elytra in general with vertically elongated maculae (Fig. 13). Male genitalia with hinge sclerites thin (Fig. 19).............................................................................. S. durangensis Johnson & Kingsolver, 1973 .

- Elytra with horizontally elongated maculae (Fig. 63). Male genitalia with hinge sclerites with apex broader (Fig. 70)....................................................................................... S. medialis (Sharp, 1885) .

13 Elytra with vertical strip of pale setae along suture......................................................... 14

- Elytra with horizontal stripor rounded patch of pale setae on submedian region................................... 15

14 Elytron without pale setae on 3rd strial interval (Fig. 29)................................. S. lawrencei Johnson, 1977 .

- Elytron with pale setae on 3rd strial interval (Fig. 92)................................... S. trinotaticollis (Pic, 1930) .

15 Integument of elytra with regularly rounded red-orange maculae and patch of pale setae (Fig. 63).. S. medialis (Sharp, 1885) .

- Integument of elytra with horizontal strip or irregularly shaped red-orange to dark brown maculae with horizontal strip of pale setae.............................................................................................. 16

16 Disc of pronotum with dense patch of setae (Fig. 38).................................... S. lebasi (Fåhraeus, 1839) .

- Disc of pronotum with evenly and sparsely distributed setae................................................. 17

17 Male genitalia with hinge sclerites strongly curved and thin, but not reaching apex of mass of spicules on subapical region (Fig. 90).............................................................. S. transversesignatus (Fåhraeus, 1839) .

- Male genitalia with hinge sclerites moderately curved with apex and base broader, reaching apex of mass of spicules on sub- apical region (Fig. 73)................................................ S. nappi Ribeiro-Costa & Reynaud, 1998 .