Key to species of Navasoleon Banks

1. Forewing vein Cup+1A reaches hind margin of forewing well beyond radial sector (Fig. 38, 40,41); hindlegs and midlegs equal or subequal to length of forelegs; foreleg tarsomere 3 (Fig. 28) less than one half length of distal tarsomere; posterior gonapophysis paddle-like and greatly expanded (Fig. 55), as wide as long; setae brush on foreleg distal tarsomere not hooked (Fig. 29); wings marked (except N. amazonas) (Brazil, French Guiana).. (brasiliensis group) 2

— Forewing vein Cup+1A reaches hind margin of forewing at level of radial sector (Fig. 42–44); hindlegs shorter, and midlegs much shorter than forelegs; foreleg tarsomere 3 as long as distal tarsomere (Fig. 30); posterior gonapophysis much longer than broad; setal brush on foreleg distal tarsomeres hooked (Fig. 30); wings unmarked (Fig. 36)........................ 4

2. Wings unmarked (Fig. 38); male (Fig. 47) with atypical gonarcus apparently partly separated in two broad halves, not arched........................ Navasoleon amazonas Stange

— Wings marked where Cup+1A meets hind margin of forewing at rhegma, and at distal portion of hypostigmatic cell (Fig. 40, 41); male (Fig. 48, 49) with arched gonarcus................ 3

3. Dorsal thorax with pale broad medial stripe from mesoscutellum to metascutellum (Fig. 12); male genitalia (Fig. 48) without large ovoid sclerite between parameres (Brazil)................................................ Navasoleon brasiliensis Miller

— Medial areas of mesoscutellum and metascutellum dark brown (Fig. 13); male genitalia with a large ovoid sclerite between paramere bases (Fig. 49) (French Guiana)....................................................................... Navasoleon egeri Stange

4. Midtibia swollen (Fig. 26); female terminalia with gonapophysis-like process extending from ventral margin of lateral gonapophysis (Fig. 62)................................................................ (tarsalis group) (Guyana) Navasoleon tarsalis Miller

— Midtibia not swollen (Fig. 19–25, 27); female gonapophysis without gonapophysis-like process extending from lateral margin of lateral gonapophysis (Fig. 54–61).. (leptocerus group) 5

5. Antenna filamentous (Fig. 37); pronotum with all setae no longer than those on clypeus (Fig. 14, 16); foreleg tarsomere 3 70% length of distal tarsomere or less; hindwing with six presectoral crossveins (Fig. 42, 44)........................................................ 6

— Antenna clavate (Fig. 36) (antenna of N. bolivianus unknown); pronotum (Fig. 15–18) with many long setae, usually longer than the longest setae on the clypeus; foreleg tarsomere 3 equal to length of distal tarsomere (Fig. 28); hindwing with seven to nine presectoral crossveins (Fig. 39,43,46).................................................................... 7

6. Hindtibia with no setae longer than tibial diameter; pronotum mostly reddish brown with large submedial stripes (Fig. 14); third abdominal tergite darkened with central pale area; (Chaco and Subandean deserts of Argentina)................ Navasoleon leptocerus (Navás)

— Hindtibia with some setae longer than tibial diameter; pronotum (Fig. 16) nearly all pale yellow except lateral margins; third abdominal tergite pale without color pattern; (low cloud forests of northwestern Argentina)............................... Navasoleon lotti Stange

7. Vertex markings (Fig. 6) with anterior dark brown nearly completely dark brown below antennae; anterior half of prothorax with median dark markings (Peru) Navasoleon lithophilus Miller

— Vertex markings (Fig. 2, 9) with anterior area pale brown, without dark brown area below antennae; anterior half of prothorax all pale............................................... 8

8. Mesoscutellum and metascutellum all pale brown (Fig. 18) (Venezuela).................................................................. Navasoleon venezolanus Stange

— Mesoscutellum and metascutellum with median dark streaks (Fig. 11) (Bolivia)............................................................ Navasoleon bolivianus (Banks)