Key to females of Stibasoma

1. Subcallus pollinose................................................................................................................................................... 2

-. Subcallus predominantly shiny............................................................................................................................... 12

2 (1). Gena with white to yellow hairs............................................................................................................................... 3

-. Gena with brown to black hairs................................................................................................................................ 6

3 (2). Pleural sclerites with dark brown to black and white hairs ...................................................................................... 4

-. Pleural sclerites with orange hairs .............................................................................................................. S. currani

4 (3). Wing brown with two conspicuous lighter areas: one hyaline at apex, along distal portion of the cells r2+3 and r4, the other yellowish, in middle, along cells c, sc, r1, r2+3, r5 and d ..................................................... S. bifenestratum

-. Wing not as described above .................................................................................................................................... 5

5 (4). Tergite 3 yellow, with two black spots laterally .................................................................... S. manauensis sp. nov.

-. Tergite 3 dark brown with dark brown hairs, except for a row of yellow hairs distally............................................. .......................................................................................................................................................... S. leucopleurale

6 (2). Wing predominantly yellowish................................................................................................................................. 7

-. Wing predominantly brownish ................................................................................................................................. 8

7 (6). Thorax with black hairs dorsally and laterally ...................................................................................... S. flaviventre

-. Thorax with yellow to orange hairs dorsally and laterally .................................................................. S. fulvohirtum

8 (6). Tergites dark brown to black with yellow marks...................................................................................................... 9

-. Tergites totally dark brown to black in dorsal view ............................................................................................... 10

9 (8). Scutum totally dark brown to black ....................................................................................................... S. theotaenia

-. Scutum dark brown to black with yellow marks ............................................................................................ S. bella

10 (8). Sternites totally dark brown to black...................................................................................................................... 11

-. Sternites dark brown to black with yellow hairs laterally ............................................................................... S. lutzi

11 (10). Palpus slender ...................................................................................................................................... S. giganteum

-. Palpus enlarged ........................................................................................................................................ S. willistoni

12 (1). Wing predominantly yellowish............................................................................................................................... 13

-. Wing predominantly brownish ............................................................................................................................... 15

13 (12). Tergite 1 dark brown and yellow .......................................................................................................................... 14

-. Tergite 1 totally yellow with yellow hairs ...................................................................................... S. ruthae sp. nov.

14 (13). Tergites 1 and 2, lateral margins yellow with yellow hairs and dark brown with dark brown hairs in middle........ .................................................................................................................................................................... S. bicolor

-. Tergites 1 and 2 dark brown to black with a stripe of yellow hairs on the distal margin ........................................... ............................................................................................................................................................ S. apicimacula

15 (12). Wing brown with hyaline apex............................................................................................................................. 16

-. Wing brown with one or more light spots .............................................................................................................. 17

16 (15). Tergites (all) dark brown to black with triangles of yellow hairs in middle of distal margin ....... S. aureoguttatum

-. Tergites 1 and 2 yellow with yellow hairs; the remaining tergites light brown with copper-red hairs S. panamensis

17 (15). Wing with two conspicuous lighter areas: one hyaline at apex, reaching the distal portion of cells r2+3 and r4 and the other in middle of the wing, yellowish, along cells c, sc, r1, r2+3, r5 and d .................................. S. chionostigma

-. Wing with apex and discal cell hyaline ..................................................................................................... S. festivum