Key to the males of Neotropical Styringomyia species

(based on the morphology of the gonostylus)

1. Stout spine­like hairs present (Figs. 10­13)................................................................... 2

­ Stout spine­like hairs absent (Figs. 14­17).................................................................... 5

2. Gonostylus much longer than broad, bearing two long spine­like hairs; extension I greatly developed, basal in position (Figs. 10, 11)........................................................ 3

­ Gonostylus almost as long as broad, bearing at least three short spine­like hairs; exten­ sion I apical in position (Figs. 12, 13)........................................................................... 4

3. Four extensions present; apex of extension I broad (Fig. 10) ....... S. mystica Alexander

­ Only three extensions present; apex of extension I narrowed (Fig. 11) .. S. youngi sp. n.

4. Extension II short, spine­like hair situated at its apex (Fig. 12) .......... S. atlantica sp. n.

­ Extension II long, spine­like hair situated at its base (Fig. 13) ..... S. paulista Alexander

5. Two apical extensions present....................................................................................... 6

­ Only one bifid apical extension present (probably resulting from the fusion of exten­ sion III and IV); anterior margin of gonostylus almost straight; slender hairs in the lat­ eral face concentrated at a protuberance near base of apical extension (Fig.

16)................................................................................................... S. amazonica sp. n. ­ Three apical extensions present; extension III and IV closely jointed; gonostylus long and slender (Fig. 17) ......................................................................... S. manauara sp. n.

6. Gonostylus more or less S­shaped; extension III relatively poorly developed; medial face with a long and relatively stout hair near base of extension IV (Fig. 14) ............... ....................................................................................................... S. simplex Alexander

­ Gonostylus constricted at base; distal part of posterior margin expanded; extension III well developed (Fig. 15) ........................................................................... S. maya sp. n.