Sobarocephala, Czerny, 1903

Lonsdale, Owen & Marshall, Stephen A., 2012, 3370, Zootaxa 3370, pp. 1-307 : 18-30

Key A—Key to the species of Sobarocephala found south of the United States, excluding those of the S. flaviseta species group.

NOTE: Species of Sobarocephala outside the flaviseta group exhibit relatively few pattern elements (such as spots, stripes, etc.), and sometimes show intraspecific variability for those pattern elements. Because of this, and because some characters used in the key couplets occasionally show intermediate states, several species are brought out at multiple parts of the key. For positive identification it is often important to examine characters of the male genitalia.

1. Frons narrowing towards back of head (Fig. 23). M 1+2 ratio greater than 2.0 and wing usually only infuscated along anterodistal margin; if wing elaborately patterned, then without marginal spot immediately after costal cell. Rectal papillae without minute comb-like structures on outer surface (Fig. 47). Usually with either i) ivory-white notopleuron (Fig. 20), or ii) densely plumose arista (entirely dense, never just at base) ( Fig. 569), minute ocellar bristles and bulging face. New World and (rarely) east Asia.................................................................... S. flaviseta species group—Go to Key B

-- Frons usually parallel-sided (Fig. 24); if frons slightly narrowing posteriorly (some S. ruebsaameni group; Fig. 25), then wing elaborately patterned ( Figs 31–39) and M 1+2 ratio less than 2.0, or gena 1/3 eye height ( S. gigantigena ). Rectal papillae with minute comb-like structures on outer surface (Figs 48a–c). Notopleuron never white and arista usually sparsely plumose ( Fig. 52); if hairs on arista densely plumose (usually only at base, as in Fig. 73), then face flat and ocellar bristles long........ 2

2. Thoracic sternites and pleurites with brown markings on at least anepisternum or katepisternum (sometimes faded and difficult to see). Bristles black.................................................................................. 3

-- Thoracic sternites and pleurites entirely yellow to white. Bristles yellow to black................................... 21

3. All coxae white or yellow. Frons and femora variable, but never with medial bands. Face usually white to yellow (entirely orange in S. lobillis ), at most with lower half dark yellow to orange.............................................. 4

-- At least mid coxa brown to orange. At least mid femur with brown band and frons at base of fronto-orbital bristles brown. Face colour variable, but usually orange to black................................................................ 16

4. Bristles dark brown with inner vertical and apical scutellar bristles yellow. One pair of lateral scutellar bristles. Pleuron entirely brown. Colour pattern as in Fig. 92......................................... S. heteroseta spec. nov. (7.10)

-- All bristles the same colour. Two pairs of lateral scutellar bristles. Pleuron yellow with brown stripes or spots............ 5

5. Pleuron with complete longitudinal sub-notal stripe. Cerci rounded and somewhat projecting past distal margin of epandrium (as in Fig. 193)....................................................................................... 6

-- Pleuron with spots or a vertical stripe, sometimes in combination with a subnotal stripe. Cerci flat, flush with distal margin of epandrium (as in Fig. 364).............................................................................. 7

6. Arista densely plumose at base ( Fig. 71). Scutellum yellow with corners brown. Scutum yellow with shoulders and postsutural stripes brown. Frons orange. Abdomen yellow with epandrium brown. Surstylus broadly rounded with circular anterodistal projection (Figs 192, 193)........................................................... S. lobillis spec. nov. (2.5)

-- Arista sparsely plumose along length (Fig. 152). Scutellum brown. Scutum brown postsuturally excluding yellow median stripe not touching scutellum. Frons yellow. Abdomen mostly brown with epandrium yellow. Surstylus small and subtriangular ( Fig. 360)............................................................ S. horizontalis spec. nov. (8.6) (in part)

7. Small bristle present in front of anterior dorsocentral bristle. Scutellum brown laterally. Notum yellow centrally. Frons yellow. .................................................................................................... 8

-- Two dorsocentral bristles. Scutellum entirely yellow or brown. Notum without lateral longitudinal stripes. Frons sometimes with brown markings................................................................................. 11

8. Antenna entirely yellow (Fig. 76). Lateral margin of scutum brown (including postpronotum)..... S. colima spec. nov. (8.3)

-- First flagellomere with spot at base of arista (Fig. 78). Scutum bivittate, with lateral margins yellow (sometimes with small spot on notopleuron and postpronotum)..................................................................... 9

9. Back of head entirely yellow to white. Anatergite (and sometimes katatergite) yellow lateral to scutellum (Fig. 78). Fore tarsi yellow...................................................................... S. howdenorum spec. nov. (8.7)

-- Back of head with one pair of stripes. Anatergite brown lateral to scutellum (excluding thin faded stripe beside inner-lateral margin). Fore tarsi light brown to brown................................................................... 10

10. Bristles dark brown. Only setulae present in front of anterior supra-alar bristle. First flagellomere with dorsal stripe (Fig. 75). Notopleuron brown posterolaterally................................................. S. verticalis spec. nov. (8.20)

-- Bristles brown. Two small bristles present in front of anterior supra-alar bristle. First flagellomere infuscated at base of arista. Notopleuron yellow along lateral margin (Fig. 80) or brown posterolaterally (Fig. 11)..................................................................................................... S. serpentina spec. nov. (8.17) (in part)

11. Femora and frons yellow. Brown spot on anepisternum....................................................... 12

-- Median bands present on at least one femur. Frons brown, at least laterally (as in Figs 115, 124, 125). Pleural stripe extending from anepisternum to katepisternum...................................................................... 14

12. Scutum largely brown postsuturally, and with postpronotum and lateral margin of notopleuron brown (Fig. 99). Gena and parafacial silvery tomentose.................................. S. xanthomelana Melander & Argo (9.65) (some females)

-- Scutum partly yellow with a central stripe that attains (or nearly attains) the anterior margin (Figs 108, 134). Gena and parafacial shining to pilose, not silvery......................................................................... 13

13. Wing uniformly dusky. Notum with thick central stripe that nearly attains anterior margin, thick lateral postsutural stripes and thin brown anterolateral margins (Fig. 108). Annulus and epandrium yellow. Legs entirely yellow. Male sternite 5 without posteromedial comb. Male cerci slightly projecting past distal epandrial margin ( Figs 204, 205). Surstyli large, broadly rounded and parallel to each other...................................................... S. tschirnhausi spec. nov. (3.16)

-- Wing darkly clouded on distal half only. Notum with singly central stripe that strongly narrows anteriorly and attains anterior margin (Fig. 134). Annulus and epandrium brown. Legs yellow with fore tarsi and fore and hind tibiae brown (excluding apex). Male sternite 5 with posteromedial comb of bristles. Male cerci sunken below distal margin of epandrium (Figs 411, 412). Surstylus small, narrow, acute and strongly curved inwards......................... S. infuscata spec. nov. (9.30)

14. Two dark wing spots ( Fig. 38). Scutellum and epandrium yellow (Fig. 124). First flagellomere with dorsal stripe.......................................................................................... S. fritilla spec. nov. (9.20)

-- Wing only pigmented along vein R 2+3 distally, or along anterior margin of wing. Scutellum brown. Epandrium yellow, orange, or brown. Antenna entirely yellow........................................................................ 15

15. Acrostichal bristle absent. Scutum with postsutural stripe that is broadly rounded laterally and (usually) connected anteriorly to notopleural spot (Fig. 125). Coxae white. Epandrium always brown. Male fifth tergite with comb of bristles...................................................................................... S. annulata Melander & Argo (9.3)

-- Acrostichal bristle present. Scutum with narrow stripe between dorsocentral rows and long supra-alar spots, or brown postsuturally; deep to shallow emargination present anteromedially (Fig. 115). Epandrium sometimes yellow or orange. Male fifth tergite without comb ( Fig. 179).................................................... S. isla Curran (7.13) (in part)

16. Scutum with central postsutural stripe (apex emarginate); if scutum almost entirely brown postsuturally, a deep central emargination will be present medially (Fig. 115). Postnotum always yellow below scutellum, if not, scutum brown behind suture with central emargination....................................................... S. isla Curran (7.13) (in part)

-- Scutum bivittate or mostly brown, sometimes excluding anterior margin and one pair of small spots in the posterior corners (Fig. 103). Postnotum entirely brown, sometimes lighter directly lateral to scutellum................................ 17

17. Notum mostly yellow with one pair of brown stripes, sometimes connected to large lateral spot. Wing dark on distal half and with two spots near base of CuA 2 and R 1 ( Fig. 39). Surstylus somewhat truncate, angled anteriorly and inwardly curved posterobasally ( Figs 237, 240)............................................................................... 18

-- Notum mostly brown, sometimes yellow along anterior margin. Wing dark on distal half or 3/5, without discrete spots. Surstylus broadly rounded or sharply pointed.................................................................... 19

18. Central vittae connected laterally to notopleural spot (Fig. 167). Pleuron entirely brown excluding meron. Tergites 6 to epandrium brown.................................................................. S. parrhasios spec. nov. (4.7)

-- Central vittae and notopleural spot separate (Fig. 168). Pleuron yellow with wide vertical stripe from the anepisternum to the anterior face of the katepisternum and the anterior face of the mid coxa; proepisternum and posterior half of anepimeron also brown. Tergites 6 to epandrium yellow................................................. S. zeuxis spec. nov. (4.11)

19. Surstylus acute and incurved (Figs 408, 409). Bristles brown. Postpronotum brown (Fig. 93) or yellow. Ecuador, Peru.................................................................................... S. daidaleos spec. nov. (9.12)

-- Surstylus broadly rounded (Fig. 333; unknown for S. vittatifrons ). Bristles dark brown to black, sometimes brown. Postpronotum yellow.......................................................................................... 20

20. Scutum brown excluding anterior margin and posterior corners (Fig. 103). Distal 3/5 of wing dark. First flagellomere yellow. Fore coxa dark brown............................................................. S. furviala spec. nov. (7.8)

-- Scutum brown excluding postpronotum (Fig. 89). Wing dusky, gradually darker on distal half. First flagellomere usually brown ventrally in females, and yellow in males. Fore coxa yellow......................... S. vittatifrons Hennig (7.25)

21. Wing pattern elaborate, with 3 or more spots; if with 2 spots, then one spot the length of, and lying directly distal to, costal cell, and the other spot at wing apex, but much darker around apex of R 2+3 ( Figs 31–39). M 1+2 ratio less than 2.0. Abdominal pattern often interrupted or notched medially and comprised of lateral spots ( Figs 52 –55, 57–60). Frons sometimes narrowing posteriorly (Fig. 25)........................................................................................ 22

-- Wing clear, lightly clouded with 1 or 2 spots (as in Figs 40–43). M 1+2 ratio more than 2.0 (often more than 3.0). Abdomen yellow to black, but rarely interrupted medially. Sides of frons parallel (Fig. 24)..................................... 29

22. Scutellum brown (at least in part). First flagellomere often infuscated at base of arista............................... 23

-- Scutellum and antenna entirely yellow..................................................................... 27

23. Scutellum brown laterally (Fig. 58).................................................... S. notalis spec. nov. (4.6)

-- Scutellum entirely brown, brown at apex or with thin yellow margin basally....................................... 24

24. Small bristle not present in front of anterior dorsocentral. Face with one dark stripe and one pair of wide, dark lateral stripes; median facial stripe continuing onto anterior margin of frons and lateral stripes continuing onto gena. First flagellomere unpigmented. Scutellum yellow on basal half (Fig. 56)....................................... S. speciosa spec. nov. (4.10)

-- Small bristle present in front of anterior dorsocentral. Face yellow to white. First flagellomere with apical spot or dorsal stripe. Scutellum mostly to entirely brown or yellow with small brown apical spot....................................... 25

25. Scutellum with brown apical spot (Fig. 55). Scutum rarely with presutural markings........... S. cacumen spec. nov. (4.1)

-- Scutellum entirely brown or with limited yellow markings along basal margin. Notal stripe extending past transverse suture.. ................................................................................................... 26

26. Narrow yellow margin at base of scutellum (Fig. 54). Postnotum yellow beneath scutellum. Epandrium yellow. Female tergite 6 yellow......................................................................... S. nebrias spec. nov. (4.4)

-- Scutellum entirely brown (Fig. 57). Postnotum brown beneath scutellum. Epandrium brown. Female tergite 6 brown........................................................................................... S. finnlaei Frey (4.3)

27. Scutum largely yellow with pair ofvery thin brown stripes basally (Fig. 53). Small bristle in front of anterior dorsocentral bristle.............................................................................. S. compta spec. nov. (4.2)

-- Notum with stripes at least half as wide as scutellum. No small bristle in front of anterior dorsocentral.................. 28

28. Notopleuron and postnotum yellow (Fig. 59). Epandrium brown. Female tergites 5 and 6 yellow... S. reducta spec. nov. (4.8)

-- Notopleuron and postnotum brown (Fig. 60). Epandrium yellow. Female tergites 5 and 6 brown laterally.............................................................................................. S. ruebsaameni Czerny (4.9)

29. Body with distinct dark patterns on notum and abdomen, or entirely dark. In males that are largely yellow, notopleuron light brown to brown...................................................................................... 30

-- Notum entirely yellow, abdomen often with light brown or faded patterns on tergites 2–5........................... 170

30. Scutellum entirely yellow, at most with thin brown transverse basal line (Fig. 70).................................. 31

-- Scutellum more extensively to completely brown, sometimes with central stripe or lateral corners brown............... 41

31. Scutum with one pair of thin brown sharply delimited stripes broadly rounded anteriorly and fading posteriorly ( Fig. 154). Notopleuron sometimes brown. Male abdomen brown posteromedially on tergites 2–4, sometimes with tergites 3–5 brown dorsally. Female abdomen brown on tergite 6 and on posteromedial parts of tergites 2–4. S. bistrigata (Kertesz) (9.5) (in part)

-- Scutum with one pair of postsutural spots or stripes. Notopleuron yellow. Abdomen brown on at least tergites 2–5........ 32

32. Scutum with a single central stripe, strongly tapering anteriorly (Fig. 70). Anterior margin of scutellum brown....................................................................................... S. surinamensis spec. nov. (8.18)

-- Scutum with one pair of spots or stripes. Scutellum entirely yellow............................................. 33

33. Scutum with one pair of ovate postsutural spots (Fig. 62).................................. S. biovata spec. nov. (9.4)

-- Scutum bivittate..................................................................................... 34

34. Length 4.0mm. Bristles dark brown. Acrostichal bristle present. Epandrium bulbous, orange, and distinctly wider than immediately preceding segments (Fig. 530)........................................ S. bulbipenis spec. nov. (9.7) (in part)

-- Length 2.6–3.8mm. Bristles yellow to brown. Acrostichal bristle usually absent. Epandrium yellow, rarely brown, and not wider than terminal abdominal segments.................................................................. 35

35. One pair of lateral scutellar bristles or anterior pair of bristles minute or much shorter than posterior pair................ 36

-- Two pairs of well developed lateral scutellar bristles........................................................ 37

36. Acrostichal bristle present. Cell bm open. Gena, parafacial and occiput silvery tomentose. Notopleuron yellow or brownish laterally ( Fig. 61). Male fore leg with tibia and tarsi brown. Epandrium yellow. Male cerci flush with distal margin of epandrium (Fig. 376). Surstylus short and somewhat bilobed (Figs 375, 376).................. S. lucibilis spec. nov. (8.10) (in part)

-- Acrostichal bristle absent. Cell bm narrowly closed. Head shiny. Notopleuron with sharp brown rectangular spot. Male fore leg yellow. Epandrium brown. Male cerci long and tapered. Surstylus long and subtriangular........... S. soosi Steyskal (7.23)

37. Bristles yellow. Fore tarsi yellow. Gena and parafacial shiny. Surstylus very narrow and incurved (Figs 450, 451)................................................................................ S. ankistrion spec. nov. (9.2) (in part)

-- Bristles yellow to brown. Fore tarsi light brown to yellow. Gena and parafacial pilose. Surstylus variable in shape, but not as above.............................................................................................. 38

38. Bristles yellow. Notal stripes short but strongly bent, approaching dorsocentral rows posteriorly (Fig. 63). Surstylus forked (Fig. 384).................................................................. S. dikros spec. nov. (8.5) (in part)

-- Bristles light brown. Notal stripes straight along dorsocentral rows. Surstylus entire................................ 39 39. Notal stripes clavate; widest anteriorly............................................. S. plaumanni spec. nov. (9.46)

-- Notal stripes of constant width or widest posteriorly......................................................... 40

40. Length 2.5–4.0mm. Ocellar bristle very thin, and sometimes short. Wing dusky apically along R 2+3 ( Fig. 41). Surstylus broadly rounded ( Fig. 548). Male with posterior comb on fifth sternite............... S. bivittata Melander & Argo (9.6) (in part)

-- Length 2.6mm. Ocellar bristle nearly as strong as postocellar bristle. Wing clear. Surstylus truncate (Fig. 357). Comb absent from male fifth sternite................................................ S. quadristylus spec. nov. (8.14) (in part)

41. Scutellum brown along base and at apex......................... S. basilobellus spec. nov. (1.3) (one Ecuadorian male)

-- Scutellum variably pigmented, but not as above............................................................. 42

42. Scutellum brown centrally, yellow laterally................................................................. 43

-- Scutellum laterally or entirely brown, sometimes only with small yellow spot in lateral corner........................ 52

43. Two lateral scutellar bristles. Wing width half length ( Figs 41-43).............................................. 44

-- One lateral scutellar bristle. Wing width sometimes 1/3 length (as in Fig. 40)..................................... 49

44. Postocellar bristle absent. Anterior margin of frons brown (Fig. 123). If scutum with median stripe, stripe trifid with lateral lines continuing as bulbous spot presuturally............................................ S. guianica Curran (7.9)

-- Postocellar bristle small to well developed. Anterior margin of frons yellow. If scutum with median stripe, then not as above. ................................................................................................... 45

45. First flagellomere with dorsal half brown in males and with distinct spot at the base of the arista in females. Notal stripe tapering anteriorly or scutum bivittate. Notopleuron and postpronotum usually brown................................... 46

-- First flagellomere entirely yellow. Notal stripe bifid or trifid, but not tapering anteriorly. Notopleuron and postpronotum yellow................................................................................................ 48

46. Notopleuron and postnotum yellow (Fig. 69)............................................ S. pilata spec. nov. (7.18)

-- Notopleuron brown and mostnotum mostly brown........................................................... 47

47. First flagellomere with dorsal half brown in males and yellow with distinct spot at base of arista in females (Fig. 110). Scutum with median stripe............................................................ S. minthomyia spec. nov. (7.17)

-- First flagellomere with infuscation at base of arista in both sexes (sometimes faint) (Fig. 158). Scutum bivittate................................................................................... S. vulgaris spec. nov. (9.64) (in part)

48. Notal stripe quadrate with three very short lines projecting anteriorly (Fig. 66). Wing slightly dusky on anterodistal margin. Male with posterior comb on fifth sternite........................................ S. epitriangulina spec. nov. (9.17)

-- Notal stripe bifid (Fig. 128). Wing darkly clouded on distal 3/5 or more (darkest toward costa). Male fifth sternite without comb................................................................ S. dorsoplicella spec. nov. (7.3) (in part)

49. Medial stripe light brown, minute, shorter than scutellum (sometimes faint and difficult to distinguish in teneral specimens) (Fig. 68). First flagellomere yellow. Bristles yellow. Wing clear...................... S. hyalina spec. nov. (7.12) (in part)

-- Medial stripe long, nearly reaching transverse suture or extending past it. First flagellomere white with small to large spot around base of arista. Wing clouded distally................................................................ 50

50. Wing width approximately half length; dusky apically and in first radial cell. Postnotum yellow with brown stripe below scutellum and one pair of thin lateral stripes (Fig. 130). Surstylus subtriangular and strongly incurved (Figs 264, 265)................................................................................ S. virgulatissimus spec. nov. (5.3)

-- Wing thin with width less than 1/3 length; first radial cell on dark apically. Postnotum without dark lateral stripes. Surstylus subtriangular, but not curved as above.................................................................... 51

51. Wing lightly clouded anterodistally. First flagellomere with dark dorsal stripe (Fig. 131). Postnotum dark below scutellum. Surstylus long and narrow (Figs 291, 292)........................................... S. epraka spec. nov. (in part)

-- Wing darkly infuscated around dm-cu, distal 1/8 of R 4 +5 and distal 1/5 of M 1 and R 2 +3. First flagellomere with spot at base of arista. Postnotum yellow. Surstylus very short (Fig. 342).... S. maquipucuna spec. nov. (8.11) (one female from Costa Rica)

52. Scutellum yellowish medially or with strong central yellow stripe.............................................. 53

-- Scutellum entirely brown, sometimes with apex yellow. If scutellum yellow laterally, then spot restricted to minute, indistinct spot in extreme anterolateral corner....................................................................... 67

53. Female with strong medium-length bristle in front of anterior dorsocentral and male with three strong postsutural dorsocentral bristles (anterior bristle 2/3 length of mid bristle, and mid bristle 3/5 length of posterior bristle). Notal stripes nearly reaching anterior margin of scutum (Fig. 72). Anterior margin of wing darkly clouded past R 1 (lighter in male). Tergite 5 brown.................................................................................. S. quadrivittata Czerny (7.21)

-- Two strong dorsocentral bristles present, at most with a small bristle in front of the anterior dorsocentral that is not much more differentiated from the surrounding setulae. Notal stripes not reaching anterior margin of scutum. Tergite 5 brown centrally. Wing variably pigmented, but not as above................................................................ 54

54. Length 4.4–5.3mm. Arista densely plumose basally. Wing darkly clouded on distal ½ or 1/3 from the costa to vein M 1. Male cerci long and projecting beyond distal margin of epandrium ( Fig. 316). Surstylus long and narrow ( Fig. 315)........... 55

-- Length 2.2–4.5mm. Arista sparsely plumose along entire length. Wing clear to dusky, at most darkly clouded along anterior margin or along R 2+3. Male cerci short and flush with distal margin of epandrium. Surstylus of various shape........... 56

55. Scutum patterned presuturally (Figs 73, 74). Wing clouded distally............................ S. lanei Curran (7.15)

-- Pattern on scutum restricted to postsutural stripes ( Fig. 81). Wing clear..................... S. amniocolis spec. nov. (7.1)

56. Notal stripe less than half width of scutellum, notopleuron yellow............................................. 57

-- Notal stripe at least 2/3 width of scutellum; notopleuron usually brown, at least in posterolateral corner................ 60

57. Small but well developed bristle in front of anterior dorsocentral. Wing dusky along anterodistal margin. Surstylus small and rounded (Figs 530, 548)............................................................................... 58

-- Usually only setulae in front of anterior dorsocentral. Wing clear. Surstylus large and broadly rounded or small and quadrate................................................................................................... 59

58. Bristles dark brown. Female postnotum yellow to light brown or orangish lateral to scutellum. Epandrium large, bulbous and usually with orange tint. Surstylus large with apical bristles on inner face long and thick (Figs 530, 531). Hypandrial complex elongate (Fig. 532), strongly projecting into abdominal cavity.................... S. bulbipenis spec. nov. (9.7) (in part)

-- Bristles light brown to brown; if darker, then female postnotum brown lateral to scutellum (otherwise brown to light brown) (see comments for S. bivittata ). Epandrium small and yellow. Surstylus small, but well developed and slightly rounded ( Figs 548, 549); bristles on inner face unmodified as above. Hypandrial complex ( Fig. 550) not noticeably enlarged............................................................................. S. bivittata Melander & Argo (9.6) (in part)

59. Length 2.6mm. Gena, parafacial and occiput pilose. Surstylus small and quadrate, with numerous small rounded bristles along the apical margin (Figs 357, 358). Fifth sternite of male with one pair of setose patches medially on posterior margin........................................................................... S. quadristylus spec. nov. (8.14) (in part)

-- Length 3.8mm. Gena pilose; parafacial and occiput shiny. Surstylus wide, higher than epandrium, and with elongate posterobasal lobe shielding an internal process (Figs 485, 486). Small rounded bristles absent from surstylus. Male with posteromedial comb on fifth sternite.............................................. S. hypopygialis Melander & Argo (9.27)

60. Bristles light brown to yellow and acrostichal bristles present. Notal pattern usually light brown with a serrated outline, composed of one pair of stripes posteriorly, and one pair of supra-alar and notopleural spots (notopleural spot sometimes absent in males) (Fig. 87). Surstylus deeply emarginate ( Fig. 378). Caribbean specimens sometimes with spots fused or reduced to small pair of short postsutural stripes................................................... S. dichotomos spec. nov. (8.4)

-- Bristles usually brown; if light brown, acrostichal bristles absent. Notal pattern variable, usually brown, and never with isolated supra-alar spot. Surstylus broadly rounded............................................................ 61

61. Notopleuron brown with yellow spot surrounding base of anterior notopleural bristle. One pair of thin postsutural stripes with strong lateral curve (Fig. 84)...................................................... S. setulocetra spec. nov. (6.1)

-- Notopleuron without yellow spots. If scutum bivittate, then not as above......................................... 62

62. Ocellar bristles shorter and thinner than postocellar bristles. Scutum with one pair of postsutural stripes (sometimes notopleuron also brown). Back of head yellow to white. Male usually with posterior comb on fifth sternite..................... 63

-- Ocellar bristles well developed. Scutum sometimes brown along the entire lateral margin, but if bivittate, stripes usually extending to the level of the postpronotum. Back of head sometimes with one pair of stripes. Male fifth sternite without comb................................................................................................... 66

63. Bristles black. Wing darkly clouded from costa to midpoint of second radial cell. Epandrium large, bulbous, and yellowishorange (Figs 536, 537)............................................................ S. tibialis spec. nov. (9.59)

-- Bristles yellow to brown. Wing sometimes dusky in first and second radial cells, but usually clear or lightly clouded apically or along R 2+3. Epandrium small and yellow................................................................... 64

64. Length less than 2.5mm. Notopleuron and antenna yellow (Fig. 164). No small bristle present in front of anterior dorsocentral bristle. Phallapodeme atrophied subapically ( Fig. 440)....................... S. ochroapicalis spec. nov. (9.40) (in part)

-- Length greater than 2.5mm. Notopleuron usually brown and first flagellomere sometimes with infuscation at base of arista. Small bristle present in front of anterior dorsocentral bristle, at least slightly stronger than surrounding setulae. Phallapodeme well developed....................................................................................... 65

65. Anterior lateral scutellar bristle minute or absent. Notopleuron and fore tibia never brown. Surstylus small, rounded, and slightly cleft medially (Fig. 376). Comb absent from male fifth sternite. Paraphallus atrophied (Fig. 377). Uncommon.............................................................................. S. lucibilis spec. nov. (8.10) (in part)

-- Anterior lateral scutellar bristle well developed. Notopleuron and fore tibia often brown. Surstylus broadly rounded, without cleft ( Fig. 549. Male with posteromedial comb on fifth sternite. Paraphallus well developed with thumb present ( Fig. 550). Common.......................................................... S. bivittata Melander & Argo (9.6) (in part)

66. Lateral margin of scutum entirely brown (Fig. 77). Antenna entirely yellow............... S. schildimyia spec. nov. (8.15)

-- Lateral margins of scutum yellow, defining long sinuate brown stripes medially (Fig. 80), but Mexican material with stripe thickened anteriorly and interrupted at suture. First flagellomere with infuscation at base of arista............................................................................................ S. serpentina spec. nov. (8.17) (in part)

67. One lateral scutellar bristle. First flagellomere entirely dark brown (Fig. 117). Scutum with short, but wide brown trilobite spot........................................................................ S. jatunsacha spec. nov. (7.14)

-- One or two lateral scutellar bristles. First flagellomere entirely or mostly yellow. Notal pattern variable................ 68

68. Face and (sometimes) frons orange. Notum yellow presuturally except lateral margin of notopleuron and (usually) postpronotum brown; brown postsuturally, sometimes extending anteriorly as medial stripe that is variably elabotated at transverse suture (Fig. 98)...................................................................................... 69

-- Face and frons variable. Notum either yellow with restricted brown pattern, or entirely brown with small yellow spots, never brown postsuturally with one pair of yellow anterior stripes................................................... 72

69. Bristles dark brown. Face orange. Scutum usually with weak to well developed presutural pair of brown medial stripes (Fig. 98). Male fifth sternite without comb of bristles. Surstylus subquadrate ( Fig. 225)................................ 70

-- Bristles light brown to brown. Face yellow to white. Scutum without anteromedial stripe. Male fifth sternite with comb of bristles. Surstylus rounded or narrowing distally............................................................... 71

70. Wing evenly dark. Back of head with one pair of orange to brown stripes. M 1+2 ratio 1.8-2.3. Common.................................................................................... S. liturata Melander & Argo (3.8) (in part)

-- Wing darker apically along radial veins. Back of head yellow with brownish spot below tubercle. M 1+2 ratio 3.1. Uncommon.................................................... S. pseudotuberculata spec. nov. (9.49) (Costa Rican females) 71. Postpronotum brown (Fig. 99). Frons usually dirty yellow to brown. Tibiae yellow (sometimes brown in females). Male tergite 1 yellow. Epandrium yellow or brown. Surstylus slightly truncated apically and with triangular spur on inner-basal face ( Figs 560, 561).................................................... S. xanthomelana Melander & Argo (9.65) (in part)

-- Postpronotum yellow or brown (Fig. 147). Frons yellow. Only fore tibia brown. Male tergite 1 brown. Epandrium orange to brown. Surstylus small, rounded and without inner-basal spur (Figs 554, 555)............... S. conciliata spec. nov. (9.11)

72. Notum entirely brown to dark brown, sometimes with one pair of yellow spots at level of transverse suture or with anterior margin yellow....................................................................................... 73

-- Notum mostly yellow with brown pattern, or if mostly brown, then with one pair of central yellow stripes or with at least one pair of spots reaching margin anterior of scutum........................................................... 85

73. First flagellomere with strong dorsal stripe ( Fig. 88). Scutellum sometimes only brown dorsally (i.e. yellow along outer margin and venter). Postpronotum and postnotum white..................................... S. anthracina spec. nov. (8.2)

-- First flagellomere at most with faint infuscation at base of arista. Scutellum entirely brown. White spots absent.......... 74

74. Wing clear. Scutum brown behind level of postpronotum, with anterior portion light yellow (Fig. 101). Light infuscation present at base of first flagellomere.................................................. S. adelphodasys spec. nov. (8.1)

-- Wing dusky or with discrete clouded regions. Scutum brown on anterior margin, on postpronotum, or both. First flagellomere entirely yellow....................................................................................... 75

75 One pair of lateral scutellar bristles. Scutum brown excluding postpronotum (Fig. 90). Legs yellow............................................................................................... S. peruana Sóos status nov. (3.12)

-- Two pairs of lateral scutellar bristles. Scutum and legs variable, but not both as above.............................. 76

76. Face with deep orange tint, at least ventrally; rarely with light spot centrally on face ( S. araguamyia ). Tibiae brown (mid tibia sometimes yellow to orange, or fore tibia yellow), at least in part. Male wing sometimes with first and second radial cells widened and with minute triangular spines along distal 2/5 of costa ( Fig. 43)......................................... 77

-- Face white to yellow or evenly brown, but if small brown triangular spot present ventrally on face, then scutum without any yellow spots (Brazilian specimens of S. nigronota ). Either fore or mid tibia, as well as hind tibiae never both brown. Male wing not modified as above ( Fig. 41).......................................................................... 79

77. Frons brown, excluding posterolateral corners (Fig. 98). Scutum with variable yellow spots, but never as below. Wing at most dusky with the distal half of the first and second radial cells darkly clouded. Surstylus subquadrate ( Fig. 225).............................................................................. S. liturata Melander & Argo (3.8) (in part)

-- Frons brown along lateral margins (with stripes sometimes united) and at the bases of the vertical bristles. Scutum brown, sometimes with one small median, emarginate spot on the anterior margin. Distal 3/5 of wing darkly clouded (darkest towards costa), or wing evenly dusky. Surstylus rounded............................................................ 78

78. Bristles light brown. Fore tibia yellow. Scutum entirely dark. Wing dusky. Surstylus broad and uncurved (Figs 201, 202). Anterior margin of hypandrium with short process (Fig. 203)................................. S. apophysis spec. nov. (3.1)

-- Bristles black. Fore tibia brown. Scutum sometimes with anteromedial spot (Fig. 100). Wing very dark distally. Surstylus narrow and with slight curve (Figs 219, 220). Anterior margin of hypandrium without process as above (Fig. 221)................................................................................. S. dimidiata (Hennig) comb. nov. (3.4)

79. Anterior margin of scutum (excluding postpronotum) usually yellow; sometimes with very small yellow spots at suture (Fig. 102). Wing very darkly clouded on (at least) the distal 3/5. Surstylus large and broadly rounded with small posteromedial projection ( Fig. 213).............................................................. S. araguamyia spec. nov. (3.2)

-- Anterior margin of scutum brown; sometimes with large yellow medial spots. Wing evenly dusky or lightly pigmented distally. Surstylus without small posteromedial projection........................................................... 80

80. Postpronotum and notopleuron yellow, notopleuron with small dark spot laterally (Fig. 91). Abdomen yellow excluding epandrium and wide central stripe on tergites 2–5............................... S. subsolana spec. nov. (9.53) (non-type)

-- Postpronotum and notopleuron brown. Abdomen entirely brown, sometimes with terminalia yellow................... 81

81. Frons yellow, excluding ocellar tubercle ( Fig. 96); dusky in some specimens. Male fifth sternite without posterior comb. Surstylus with oblique angle on distal margin ( Fig. 195) and with numerous strong small rounded bristles along inner face ( Fig. 196)....................................................................... S. paripollicis spec. nov. (3.10)

-- Frons brown, at least laterally. Male with posteromedial comb on fifth sternite. Surstylus rounded apically, with small rounded bristles absent (larger spines sometimes present)............................................................ 82

82. Bristles light brown to brown. Head not infuscated at base of vertical bristles. Postnotum entirely brown. Surstylus shorter than epandrium.......................................................................................... 83

-- Bristles black to dark brown. Head with brown spot around base of vertical bristles and (usually) deep yellow emargination on brown frons. Postnotum sometimes yellow or light brown below scutellum. Surstylus as long as epandrium............. 84

83. Tibiae brown to light brown. Surstylus relatively narrow, constricted medially; inner distal margin with several long, dark spines (Figs 512, 513). Paraphallus without thumb (Fig. 514).... S. pseudotuberculata spec. nov. (9.49) (Costa Rican males)

-- Tibiae yellow. Surstylus small and rounded; inner distal margin with thin, pale bristles (Fig. 557, 558). Paraphallus with thumb (Fig. 559)............................................................. S. nigronota Melander & Argo (9.39)

84. Legs light yellow. Antenna (excluding arista) entirely light yellow. Wing dusky. Posterior margin of surstylus sinuate ( Figs 396, 399).................................................................... S. subsolana spec. nov. (9.53)

-- Legs yellow, sometimes with fore tarsi and tibiae brown. Antenna (excluding arista) yellow. Wing dusky, but lighter on basal half. Posterior margin of surstylus straight (Fig. 402).................................. S. spatulata spec. nov. (9.51)

85. Basal ¼ of scutum brown with lateral margins brown postsuturally and postpronotum brown (Fig. 98). Face orange, at least on the ventral half. Surstylus small and broadly rounded (appearing quadrate, Fig. 225) with numerous small rounded bristles along the inner surface of the apical margin ( Fig. 226)..................... S. liturata Melander & Argo (3.8) (in part) -- If posterior margin of scutum brown (due to the basal fusion of postsutural stripes), then postpronotum and lateral margins behind transverse suture yellow. Face and surstylus variable, but not in the above combination....................... 86

86. Scutum with central brown stripe or basal quadrate spot, sometimes highly reduced................................ 87

-- Scutum yellow centrally between dorsocentral rows, sometimes brown along posterior margin due to basal fusion of lateral postsutural stripes.................................................................................... 125

87. Lateral margin of scutum brown, sometimes only as a thin faded lateral margin, or only basally and along notopleuron.... 88

-- Lateral margin of scutum entirely yellow, sometimes with small lateral spot (usually supra-alar or notopleural)......... 102

88. Central stripe widely connected to lateral brown margins anteriorly, leaving scutum almost entirely brown with one pair of lateral yellow stripes (Fig. 105). Frons orange centrally and brown laterally. Surstylus and epandrium subequal in length and height with surstylus broadly rounded (Fig. 198, 199)..................................... S. patina spec. nov. (3.11)

-- Central stripe not fused to lateral brown markings apically. Frons sometimes darkly pigmented, but never strongest laterally. If surstylus is as long as epandrium, then it is not as high....................................................... 89

89. Central stripe bifid or trifid............................................................................. 90

-- Central stripe single, usually tapering to a point apically...................................................... 97

90. Fore legs, notopleuron and postnotum entirely yellow. Central stripe broadly rounded laterally, extensively joined to lateral markings basally, and divided anteriorly into a thin tapering central process and a pair of thick, anteriorly rounded, lateral stripes (Fig. 116)........................................................ S. lumbalis (Williston) (9.35) (in part)

-- Notopleuron usually brown, at least posterolaterally. Central stripe narrower, restricted to space between dorsocentral rows. Postnotum usually brown, at least in part. Fore tarsi (and usually the fore tibia) brown.............................. 91

91. Arista densely plumose basally (Fig. 122). Lateral margin of scutum yellow above alar base. Postpronotum and notopleuron sometimes brown.......................................................... S. fuscina spec. nov. (9.21) (in part)

-- Arista sparsely plumose along entire length. Lateral margin of scutum brown above alar base. Postpronotum yellow and notopleuron sometimes brown laterally......................................................................... 92

92. Bristles dark brown. Central notal stripe trifid with all line tips reaching anterior margin of scutum (Fig. 107). Tibiae yellow with brown mottling. Surstylus truncate (Figs 216, 218).................................... S. bucki spec. nov. (3.3)

-- Bristles yellow to brown. Central stripe bifid or trifid, if trifid then not extending to anterior margin of scutum. Tibia uniformly pigmented. Surstylus rounded or tapering apically........................................................... 93

93. Notal stripe bifid (Fig. 144). First flagellomere with small spot at base of arista. Abdominal pattern reduced, with small posteromedial spot on tergite 2 and with anterior corners of tergites 3-5 yellow. Entire first radial cell of wing clouded, distal half of second radial cell clouded, and distal 1/3 of third radial cell clouded. Comb absent from posterior margin of male fifth sternite. Surstylus narrow and as high as epandrium ( Fig. 270). Cerci rounded and projecting beyond margin of epandrium ( Fig. 271)............................................................ S. fissura spec. nov. (7.6) ( Mexico and Costa Rica)

-- Notal stripe usually trifid; if bifid (some S. thrinax and some Bolivian and Brazilian specimens of S. dorsata ), first flagellomere entirely yellow. At least two abdominal tergites entirely brown when viewed dorsally. Wing clear or clouded apically. Male with posterior comb on fifth sternite. Surstylus variable, but not as high as epandrium. Cerci flush with distal margin of epandrium or sunken...................................................................................... 94

94. Median projection of trifid notal stripe much longer than lateral projections, with outline of projections sharp (Fig. 120). Female with wide brown spot on tergite 1. Tergite 5 with central stripe strongly tapered apically. Surstylus somewhat truncated apically (Fig. 542)............................................................. S. polypectica spec. nov. (9.47)

-- Median projection on central stripe shorter than lateral projections, but if median projection longer (rare), then margins of notal stripe faded and poorly defined. Female tergite 1 yellow, or with minute median spot. Tergite 5 brown. Surstylus not as above. ................................................................................................... 95

95. Acrostichal bristle present. Small bristle present in front of anterior dorsocentral. Legs entirely yellow (with a slight browning at the base of the hind tibia). Postnotum entirely yellow (Fig. 136). Coxae yellow. Surstylus sickle-shaped ( Figs 482, 483).................................................................................. S. falcata spec. nov. (9.18)

-- Acrostichal bristle absent. Only two dorsocentral bristles present. Legs at least with fore tarsi (and usually fore tibia) light brown to brown. Postnotum almost always with light brown stripes laterally. Coxae white. Surstylus triangular or rounded... ................................................................................................... 96

96. Bristles brown. Lateral projections on central stripe extending past transverse suture, with central projection usually as long as lateral projections (median projection sometimes reduced in some South American specimens); median stripe often connected to lateral brown margins basally ( Fig. 119). Surstylus strongly angled, subtruangular (Figs 545, 546)............................................................................................ S. angulata spec. nov. (9.1) (in part)

-- Bristles light brown to yellow. Lateral projections sometimes extending to, but not past, the transverse suture, with the central projection very short; median stripe separate from lateral brown margins (Fig. 121). Surstylus small and rounded (Fig. 429, 430)................................................................ S. dorsata Czerny (9.13) (some females)

97. Fore tarsi light brown. Tibiae yellow. Abdomen largely yellow, with wide central stripe extending from posterior margin of tergite 2 to a small spot on tergite 6 (Fig. 109). Epandrium yellow. Surstylus as as high as epandrium and broadly rounded (Fig. 207)......................................................................... S. emarginata spec. nov. (3.5)

-- Fore tarsi brown. Tibiae usually brown, at least on fore leg. Abdomen entirely brown, sometimes with tergite 1 and annulus or female terminalia yellow. Epandrium brown, at least at base. Surstylus shorter than epandrium...................... 98

98. Tibiae brown. Arista sparsely plumose along entire length. Male wing sometimes with first and second radial cells widened, with minute triangular spines along the distal 2/5 of the costa ( Fig. 43)........................................... 99

-- Tibiae yellow, with fore tibia sometimes brown. Arista usually densely plumose basally. Male wing unmodified ( Fig. 41)...................................................................................................... 101 99. Frons yellow. Back of head sometimes with small spot below ocellar tubercle. Brown lateral margin of scutum entire ( Figs 111, 112). Central stripe extending to suture, sometimes continuing anteriorly as a thin line. Postnotum yellow.................................................................................................. S. epeira spec. nov. (3.6)

-- Frons brown. Back of head entirely yellow or with one pair of stripes. Brown lateral margin of scutum with yellow notch behind notopleuron. Central stripe extending to suture tapering apically. Postnotum brown, at least in part............. 100

100. Acrostichal bristle absent. Head as wide as thorax (Fig. 113). Frons usually evenly brown. Face brown with gena and clypeus yellow. Back of head with one pair of stripes. Central stripe not reaching anterior margin of scutum. Epandrium yellow with large dorsomedial spot............................................................. S. sinuata spec. nov. (3.14)

-- Acrostichal bristle present. Head much wider than thorax (Fig. 114). Anterior margin of frons black. Face, gena, and clypeus (excluding lateral margins of face) black. Back of head yellow to white. Central stripe reaching anterior margin of scutum. Epandrium orange....................................................... S. latipennis Melander & Argo (3.7)

101. Bristles dark brown. Clypeus and distal 1/3 of palpus black. Back of head with one pair of stripes. First flagellomere with brown spot at base of arista ( Fig. 104). Tergite 1 brown. Anterior 1/3 of wing darkly clouded..... S. palpata spec. nov. (3.9)

-- Bristles brown to yellow. Clypeus and palpus entirely yellow. Back of head yellow to white. Antenna entirely yellow (Fig. 106). Tergite 1 yellow. Wing clear to slightly dusky............................ S. plumatella Melander & Argo (3.13)

102. Notal stripe discontinuous centrally (Fig. 118). Arista densely plumose on basal 2/3............ S. disrupta spec. nov. (1.4)

-- Notal stripe entire. Arista usually sparsely plumose......................................................... 103

103. Notal stripe reaching or exceeding transverse suture........................................................ 104

-- Notal stripe short, not reaching transverse suture.......................................................... 117

104. Notal stripe tapering to a single point anteriorly........................................................... 105

-- Notal stripe bifid, trifid, or reaching anterior margin of scutum; never tapering to a point before anterior margin........ 110

105. Notal stripe swollen medially (less pronounced in females) (Fig. 126). First flagellomere with small spot at base of arista. Female face orange. Surstylus truncate and widest distally; posterior margin with a number of elongate bristles (Figs 467, 468)............................................................................... S. bulbosus spec. nov. (9.8)

-- Notal stripe widest basally. First flagellomere yellow or with dark dorsal stripe. Face yellow in both sexes. Surstylus variable, but not as above..................................................................................... 106

106. Notal stripe sometimes with internal yellow stripe (Fig. 133). Notopleuron with faded brown spot in posterolateral corner. Fore and hind tibia brown. Surstylus with swollen anterobasal lobe (Fig. 324)....................... S. tecta spec. nov. (7.24)

-- Notal stripe without internal yellow stripe. Notopleuron usually yellow. Hind tibia sometimes brown. Surstylus variable, but without swollen anterobasal lobe...................................................................... 107

107. Length 4.5-5.3mm. Bristles usually yellow. Posterior lateral scutellar bristle weak to absent. First flagellomere with dark dorsal stripe (Fig. 131). Surstylus long and very narrow, angled anteriorly (Figs 291, 292)....... S. epraka spec. nov. (7.4) (in part)

-- Length 2.6-4.0mm. Bristles light brown to brown. Both lateral scutellar bristles well developed or anterior bristle reduced to absent. First flagellomere entirely yellow or with infuscation at base of arista. Surstylus broad and rounded apically...... 108

108. Fore tibia brown (female sometimes with all tibiae light brown to brown). Epandrium yellow. Male wing sometimes with small anterodistal spines ( Fig. 43). Male with posterior comb on fifth sternite. Male cerci sunken below distal margin of epandrium (Fig. 430)............................................................. S. dorsata Czerny (9.13) (in part)

-- All tibiae yellow. Epandrium brown. Male wing unmodified. Comb absent from male fifth sternite. Cerci rounded and slightly projecting beyond, or flush with distal margin of epandrium................................................. 109

109. Two pairs of lateral scutellar bristles. Supra-alar spot present (Fig. 132). Male frons yellow. Tibiae yellow in both sexes.................................................................................... S. prolixa spec. nov. (7.19)

-- One pair of lateral scutellar bristles. Supra-alar spot absent. Male frons brownish-yellow. Female mid and hind tibiae brown............................................................. S. maquipucuna spec. nov. (8.11) (most specimens)

110. Notal stripe trifid with central projection small and nub-like and supra-alar spot present ( Fig. 119). Stripe on tergite 2 wide along basal margin and narrow anteriorly. Epandrium dark yellow to orange. Surstylus angulate, subtriangular (Figs 545, 546)........................................................................ S. angulata spec. nov. (9.1) (in part)

-- Notal stripe usually not as above, but if trifid and central projection reduced, supra-alar spot absent. Tergite 2 with wide, broadly rounded central stripe. Epandrium yellow. Surstylus variable, but not as above............................ 111

111. Arista densely plumose basally. Posterior corner of scutum with brown spot (Fig. 122). Central stripe consisting of quadrate basal spot and three very thin projecting lines. Notopleuron and postpronotum brown.... S. fuscina spec. nov. (9.21) (in part)

-- Arista sparsely plumose. Lateral margin of scutum yellow, sometimes with supra-alar spot. Central stripe bifid or trifid with lateral anterior projections well developed; rarely stripe reaching anterior margin................................. 112

112. Notal stripe trifid (median projection sometimes reduced in South American specimens) or occasionally reaching anterior margin of scutum. Male wing sometimes with minute triangular spines distally ( Fig. 43).............................. 113

-- Notal stripe bifid. Male wing unmodified ( Fig. 41)......................................................... 114

113. Face yellow. Fore tibia and tarsi light brown to brown. Surstylus small and rounded with tubercle-like bristles absent (Figs 429, 430). Cerci sunken........................................................... S. dorsata Czerny (9.13) (in part)

-- Face (excluding thin lateral stripe), parafacial, and anterior margin of gena dark brown. Legs entirely yellow. Surstylus truncate and widest distally, with long, stout tubercle-like bristles apically (Figs 509, 510). Cerci flush with distal margin of epandrium........................................................ S. pseudotuberculata spec. nov. (9.49) ( Trinidad)

114. Occiput silvery tomentose on anterior half. Supra-alar spot sometimes present. Notal stripe divided nearly to base (Fig. 129). Surstylus broad and as high as epandrial height, inner face covered with numerous stout, pointed bristles (Figs 183, 184)......................................................................... S. basilobellus spec. nov. (1.3) (in part)

-- Occiput shiny. Supra-alar spot absent. Notal stripe emarginate, with notch tapering before base of scutum. Surstylus narrow and shorter than epandrium, with short, rounded bristles apically............................................... 115

115. Ocellar bristles well developed. Anterior lateral scutellar bristle reduced. First flagellomere with dorsal stripe or strong dorsal spot ( Fig. 127). Cerci large and quadrate (Fig. 280). Surstylus truncate apically, strongly curved inwards (Figs 279)..................................................................................... S. quadratus spec. nov. (7.20)

-- Ocellar bristles weak to minute. Lateral scutellar bristles similar in length. First flagellomere entirely yellow. Cerci small. Surstylus rounded..................................................................................... 116

116. Bristles light brown. Wing lightly clouded along anterior margin. Legs light yellow. Surstylus with anterior margin entire (Fig. 327). Cerci rounded and slightly projecting past distal margin of epandrium.................. S. sectilis spec. nov. (7.22)

-- Bristles dark brown. Distal 3/5 of wing darkly clouded. Fore tarsi and fore and hind tibiae light brown. Surstylus with anteromedial internal fold ( Fig. 330). Cerci flush with distal margin of epandrium....... S. dorsoplicella spec. nov. (7.3) (in part)

117. Ocellar bristle minute. Supra-alar spot present (sometimes faint) ( Fig. 119). Hind tibia sometimes light brown and mid tibia always yellow. Tergite 5 sometimes yellow. Surstylus angled, subtriangular (Figs 545, 546). Epandrium dark yellow to orange. …..................................................................... S. angulata spec. nov. (9.1) (in part)

-- Ocellar bristle small to well developed, usually thinner than postocellar. Supra-alar spot absent. If hind tibia brown, mid tibia also brown. Tergite 5 brown. Surstylus rounded apically. Epandrium yellow...................................... 118

118. Notal stripe poorly defined, broadly rounded and extending outside dorsocentral rows (Fig. 116)............................................................................................. S. lumbalis (Williston) (9.35) (in part)

-- Notal stripe well defined, with margins straight and sometimes slightly convergent anteriorly; sometimes reduced, but never as above............................................................................................ 119

119. Postpronotum and notopleuron light brown (Fig. 137). Epandrium somewhat large and barrel-shaped, with surstyli small, triangular, and pointed towards each other ( Figs 533, 534). Epiphallus haired. Paraphallus as in Fig. 535................................................................................................ S . idiogenes spec. nov. (9.28)

-- Postpronotum yellow. Genitalia variable, but never as above................................................. 120

120. Anterior lateral scutellar bristle small. Fore and hind tibiae light brown or brown. Parafacial and anterodorsal margin of gena silvery-tomentose. Male wing sometimes with small discrete subapical spot on R 2+3 ....... S. subapiculata spec. nov. (9.52)

-- Lateral scutellar bristles similar in length. Fore tibia yellow or brown, but hind tibia always yellow. Parafacial and gena entirely silvery-tomentose. Wing clear or dusky along R 2+3 distally............................................. 121

121. Central stripe narrow, mottled with yellowish spots and with sharp triangular emargination (Fig. 143). Coxae yellow. Male wing with R 2+3 strongly bent towards costa and with small spines along anterodistal margin of costa. Male fifth sternite without comb of bristles. Surstylus triangular, with small rounded bristles apically and long, stout bristles basally (Figs 222, 223).................................................................................. S. spinaria spec. nov. (3.15)

-- Central stripe not narrowed or mottled, and usually trifid (particularly males). Fore coxa usually white. Male wing unmodified. Male with posterior comb on fifth sternite. Surstylus variable, but not small and triangular.......................... 122

122. Bristles brown. Postnotum yellow. Sternites 6 and 7 of annulus (ventral portion) atrophied ( Fig. 506)................................................................................................ S. grammula spec. nov. (9.25)

-- Bristles yellow to light brown. Postnotum usually light brown, at least in part. Sternites of annulus well developed...... 123

123. Small bristle present in front of anterior dorsocentral. Fore tarsi yellow. Male usually with one pair of spots posterolaterally on scutum ( Fig. 135). Surstylus small and rounded (Fig. 441)................................. S. thrinax spec. nov. (9.57)

-- Usually only two dorsocentral bristles. Fore tarsi brown. Scutum without spots. Surstylus with strong basal lobe. Females unknown.......................................................................................... 124

124. Ocellar bristle well developed. Fore tibia yellow. Tergite 6 brown. Surstylus with anterobasal lobe (Fig. 476); surstyli symmetrical (Fig. 477)................................................................. S. tridentata spec. nov. (9.60)

-- Ocellar bristle much smaller than postocellar. Fore tibia brown. Tergite 6 yellow. Surstylus with posterobasal lobe; surstyli asymmetrical (Figs 500, 501)..................................................... S. phimosis spec. nov. (9.45)

125. Each side of scutum with two longitudinal stripes connected by a thin line anteriorly (Fig. 169)....................................................................................... S. archisobarocephala spec. nov. (1.1) (in part)

-- If patterned, only one pair of postsutural stripes present..................................................... 126

126. Scutum with one pair of minute brown circular spots medially (Fig. 165). Epandrium brown. Male with very small faded brown markings on the notopleuron and posteriorly on the scutum.......................... S. oculata spec. nov. (9.41)

-- Scutum entirely yellow, vittate, or with lateral margins brown. Epandrium variably yellow or brown.................. 127

127. Most of the dorsal half of first flagellomere dark brown (Fig. 156). Anterior margin of scutum with small quadrate spot, notched posteriorly............................................................. S. maculata spec. nov. (9.36)

-- First flagellomere entirely yellow, with an infuscated spot at the base of the arista, or with a thin dorsal stripe. Anterior margin of scutum yellow (postpronotum sometimes darker)........................................................ 128

128. Lateral margin of notum entirely brown, sometimes excluding postpronotum..................................... 129

-- Lateral margin of scutum entirely or partly yellow, at least at base or around transverse suture....................... 140

129. Frons brown to dark yellow in part, at least faintly around bases of fronto-orbital bristles; sometimes with short stripe in front of ocellar tubercle. Face sometimes black. First flagellomere sometimes dark yellow on outer face, or with infuscation around base of arista. Back of head sometimes with one pair of stripes............................................... 130

-- Frons yellow, excluding ocellar tubercle. Face yellow. First flagellomere entirely yellow to white; at most with thin, indistinct spot around base of arista. Back of head yellow to white..................................................... 132

130. Only two dorsocentral bristles. First flagellomere with bold, large, dark dorsal spot (Fig. 150). Back of head yellow to white. Male face yellow. Male fore tarsi brown. Epandrium entirely yellow...................... S. mexicana spec. nov. (7.16)

-- Small bristle present in front of anterior dorsocentral bristle. First flagellomere at most weakly infuscated laterally and dorsally or at the base of the arista. Back of head usually with well-defined stripes. Male face sometimes partly brown. Male fore tarsi yellow to white. Epandrium brown, at least in part......................................................... 131

131. Bristles brown. Frons not modified as below. Lateral brown margin on scutum entire or with one emargination in front and behind notopleuron ( Fig. 145). Postnotum entirely brown. Antenna basal to arista white, sometimes with infuscation at base of arista. Male face and parafacial (entirely or partly) dark brown. Epandrium entirely brown. Surstylus small, rounded and with inner-basal spur (Figs 566, 567). Cerci flush with distal margin of epandrium................ S. centrella spec. nov. (9.10)

-- Bristles dark brown to black. Frons with shallow ridge from base of inner vertical bristle to base of hind fronto-orbital bristle. Lateral brown margin on scutum sometimes with deep emargination at notopleuron ( Guatemala, Mexico) (Fig. 151). Postnotum brown lateral to scutellum. Outer lateral face of first flagellomere dark yellow. Male face yellow or with central brown spot. Epandrium brown laterally. Surstylus long and narrow, without inner-basal spur (Figs 297, 298). Cerci long and projecting beyond distal margin of epandrium...................................... S. aquilonaria spec. nov. (7.2) (in part)

132. Bristles black (yellow on pedicel). Scutum entirely brown lateral to dorsocentral rows (i.e., lateral brown margin perfectly straight along interior face) (Fig. 149). First flagellomere white. Distal 1/3 of first radial cell clouded. Abdomen with large brown spots on posterior margin of tergites from segment 2 to annulus. Male fifth sternite without comb of bristles. Surstylus narrow and elongate ( Figs 294, 295). Cerci projecting................................... S. eukteana spec. nov. (7.5)

-- Bristles yellow to light brown. Central yellow stripe widening anteriorly (that is, lateral brown margin usually with broad to acute emargination at some point along interior margin, or noticeably inset at or in front of notopleuron). First flagellomere yellow. Wing clear, dusky, or clouded apically. Abdomen not as above, more extensively pigmented dorsally. Surstylus rounded, sometimes small. Male with posterior comb on fifth sternite. Cerci flush with distal margin of epandrium or slightly sunken............................................................................................ 133

133. Central yellow stripe on scutum open at both ends (Fig160 - solid line; compare to dotted line). Surstylus large and subtriangular with apex broadly rounded (Fig. 423)................................. S. protea spec. nov. (9.48) ( St. Lucia male)

-- Central yellow stripe tapering to a point posteriorly (i.e., lateral brown margins meeting posteriorly in front of scutellum, at least as a thin faded prescutellar transverse stripe). Surstylus not as above....................................... 134

134. All tibiae brown. Uncommon........................................................................... 135

-- Tibiae (sometimes excluding fore tibia or occasionally hind tibia in very few females) yellow. Relatively common..... 136

135. Arista densely plumose basally (Fig. 146). Acrostichal bristle absent. Postpronotum light brown. Lateral margin on median stripe entire, only flaring at level of postpronotum. Postnotum brown....................... S. thysania spec. nov. (9.58)

-- Arista sparsely plumose. Acrostichal bristle present. Anterior half of postpronotum brown (Fig. 148). Lateral margin of median yellow stripe with elongate, thin emargination. Postnotum brown lateral to scutellum............ S. elegans Czerny (9.16)

136. Postnotum yellow, at least in part. Anterior margin of wing dusky. Female tergite 7 usually brown. Epandrium brown, light brown or orange, at least in part........................................................................ 137

-- Postnotum brown. Wing at most with anterodistal clouding. Female tergite 7 yellow. Epandrium yellow............... 138

137. Postnotum brown lateral to scutellum (sometimes also with thin median stripe below scutellum) (Fig. 147). Some females with stripes behind head. Male tergite 1 brown. Epandrium orange to brown.................... S. conciliata spec. nov. (9.11)

-- Postnotum yellow (Fig. 161). Back of head always yellow. Male tergite 1 yellow. Epandrium yellow with light median spot......................................................................... S. synapta spec. nov. (9.55) (in part)

138. Ocellar bristles usually strong. Wing clear. Surstylus relatively narrow and short (Fig. 444). Pregonite arched (Fig. 446). Paraphallus thin, without thumb..................................................... S. valida (Williston) (9.61)

-- Ocellar bristles thinner than postocellar bristles. Distal ¼ of wing usually clouded, rarely clear. Male genitalia not as above.................................................................................................... 139

139. Surstylus as high as epandrium (Fig. 423). Cerci sunken (Fig. 424). Hypandrium with two long bristles (Fig. 425). Postpronotum yellow. Fore tibia brown................................. S. protea spec. nov. (9.48) (some Mexican specimens)

-- Surstylus short and rounded ( Fig. 539). Cerci flush with distal margin of epandrium ( Fig. 540). Only one long hypandrial bristle ( Fig. 541). Postpronotum sometimes light brown. Fore tibia usually yellow... S. xanthotibialis spec. nov. (9.66) (in part)

140. Notal stripes absent or less than half the width of the scutellum basally, but sometimes appearing wider if joined to other stripes basally as in Figs 170 and 171, where stripe is elongate and tapering apically. First flagellomere entirely yellow. Lateral margin of scutum entirely yellow ( S. bistrigata and S. virilipeza sometimes with faded spot present posterolaterally on notopleuron).................................................................................................. 141

-- Notal stripes at least half the width of the scutellum basally (usually as wide as the scutellum). First flagellomere variable in colouration. Notopleuron and postpronotum sometimes brown............................................... 153

141. Notal stripes highly reduced to absent, never stronger than in Fig. 172. Male cerci sunken below distal margin of epandrium................................................................................................... 142

-- Notal stripes distinct. Male cerci variable................................................................ 145

142. Ocellar bristle absent. Male fore tarsi laterally flattened and bicoloured (Fig. 45). Occiput silvery tomentose. Postnotum light brown lateral to scutellum (Fig. 175)................................................ S. virilipeza spec. nov. (9.63)

-- Ocellar bristle present. Male fore tarsi unmodified and unicolourous (Fig. 44). Occiput shiny. Postnotum yellow....... 143

143. Notal stripes, if not entirely absent, slightly inset from lateral margin of scutellum. Pigment on scutellum sometimes faded basally (Fig. 172). Male wing sometimes with minute triangular spines distally on costa ( Fig. 43)............................................................................................... S. lineola spec. nov. (9.32) (in part)

-- Notal stripes, if not entirely absent, at (or just lateral to) lateral margin of scutellum. Scutellum entirely brown. Male wing unmodified ( Fig. 41)................................................................................. 144

144. Acrostichal bristle absent. Abdomen brown dorsally on tergites 2-6 (Fig. 174). Gena and parafacial shiny. Wing dusky around R 2+3 distally. Surstylus not more than 2/3 height and length of epandrium (Figs 420, 421). Phallapodeme not fused to hypan drium (Fig. 422). Common....................................................... S. vestigialis spec. nov. (9.62)

-- Acrostichal bristle small. Abdomen with wide brown stripe on tergites 2-4 and with faded central spot or median stripe on tergite 5 (Fig. 173). Gena and parafacial pilose. Wing clear. Surstylus over 2/3 length of epandrial length and height (Fig. 462). Phallapodeme fused to hypandrium anteriorly (Fig. 463). Uncommon..... S. ovata spec. nov. (9.42) (one male from Brazil)

145. Base of arista densely plumose ( Fig. 170). Ocellar bristles small and thin. Small triangular spot sometimes present basally between notal stripes............................................................. S. echinata spec. nov. (9.15)

-- Arista sparsely plumose along entire length. Ocellar bristle subequal to postocellar bristle. Scutum yellow between notal stripes........................................................................................... 146

146. Length 3.5-4.0mm. Bristles dark brown to black. Epandrium tinted with orange.................................. 147

-- Length 3.3-3.4mm. Bristles yellow to brown. Epandrium yellow.............................................. 148

147. Acrostichal bristle well developed. Notal stripes touching posterior margin of scutum and without any medial markings (Fig. 86, dotted lines). Pigment on scutellum faded apically. Epandrium large, bulbous (Fig. 530) and dark yellow or lightly tinted with orange............................................................ S. bulbipenis spec. nov. (9.7) (in part)

-- Acrostichal bristle absent. Notal stripes not touching posterior margin of scutum and with small triangular spot in front of scutellum (Fig. 157). Scutellum without faded regions. Epandrium not wider than terminal segments of abdomen....................................................................................... S. grimaldii spec. nov. (9.26)

148. Fore tarsi yellow. Male cerci sunken below distal margin of epandrium ( Fig. 427)....... S. lineola spec. nov. (9.32) (in part)

-- Fore tarsi usually light brown to brown; if yellow (rare), male cerci sunken or flush with distal margin of epandrium.... 149

149. Ocellar bristle thin. Pleuron white. Male tergites 2-5 brown dorsally (Fig. 158). Epandrium large and barrel-shaped or slightly swollen (Fig. 521) and with orange tint....................................... S. vulgaris spec. nov. (9.64) (in part)

- Ocellar bristle subequal in width to postocellar bristle. Pleuron largely yellow. Colour of male abdomen variable. Epandrium small, not noticeably heightened or enlarged............................................................. 150

150. Scutellum light brown and often faded to yellow centrally ( Fig. 154). Postnotum sometimes with thin light brown stripe below scutellum. Wing dusky at wing apex and anterodistal edge........................ S. bistrigata (Kertesz) (9.5) (in part)

-- Scutellum entirely brown. Postnotum sometimes striped. Wing clear or clouded distally............................ 151

151. Anterior dorsocentral bristle 2/3 length of posterior bristle. Postnotum with brown stripe below scutellum (Fig. 160). Coxae yellow................................................................... S. protea spec. nov. (9.48) (in part)

-- Anterior dorsocentral bristle 3/5-¾ length of posterior bristle. Postnotum entirely ellow. Coxae white................ 152

152. Scutellum usually yellowish basally (Fig. 172). Clypeus white. Male wing sometimes with minute spines along the anterodistal margin of the costa. Surstylus small and rounded ( Fig. 426). Male cerci sunken ( Fig. 427)..................................................................................................... S. lineola spec. nov. (9.32) (in part)

-- Scutellum entirely brown (Fig. 173). Clypeus yellow. Male wing unmodified. Surstylus approximately 2/3 height of epandrium (Fig. 462). Male cerci flush with distal margin of epandrium......................... S. ovata spec. nov. (9.42) (in part)

153. Arista densely plumose basally. Bristles yellow. Acrostichal bristle present. Posterior notal stripes reaching, or exceeding transverse suture. First flagellomere infuscated at base of arista. Surstylus long and narrow or large and lobate. Male cerci projecting........................................................................................... 154

-- Arista sparsely plumose along entire length. Bristles light brown to black. Acrostichal bristle sometimes absent. Posterior notal stripes not reaching transverse suture. First flagellomere with spot at base of arista or entirely yellow. Surstylus rounded apically, and usually small. Cerci flush with distal margin of epandrium or sunken.................................. 156

154. Notal stripes long, thin and pointed (Fig. 171). Female abdomen with narrow central stripe on tergite 6 and with tergite 7 brown......................................................................... S. freidbergi spec. nov. (7.7)

-- Notal stripe rounded anteriorly, sharply outlined and separate at base. Female abdomen with tergite 6 yellow or brown, and with tergite 7 yellow................................................................................ 155

155. Notal stripe sinuate, gracile anteriorly, and anteriorly joining dark lateral stripe (Fig. 169). Wing clouded on distal 1/3 along R 2+3. Male tergite 6 yellow. Surstylus large and broadly rounded with anterobasal lobe (Figs 180, 181)................................................................................ S. archisobarocephala spec. nov. (1.1) (in part)

-- Notal stripe broadly rounded apically, lateral margin of scutum yellow (Fig. 166) and sometimes with elongate internal yellow spot. Wing dusky. Male tergite 6 light brown. Surstylus long and narrow ( Fig. 303)....... S. hispidifunda spec. nov. (7.11)

156. Notopleuron yellow.................................................................................. 157

-- Notopleuron brown, at least in posterolateral corner........................................................ 163

157. Lateral margin of scutum entirely brown behind notopleuron (Fig. 152)............ S. horizontalis spec. nov. (8.6) (in part)

-- Lateral margin of scutum yellow, at least in part, behind notopleuron........................................... 158

158. Bristles brown to dark brown. Postsutural stripes very wide and rounded ( Fig. 162). Fore and hind tibiae brown. Strong, distinct, medium-length bristle present in front of anterior dorsocentral bristle................ S. pectinaria spec. nov. (9.43)

-- Bristles light brown to brown, but never dark brown. Postsutural stripes rarely as wide as those above. Fore tibia yellow or brown. If hind tibia brown, only two dorsocentral bristles present.............................................. 159

159. Small but well developed bristle present in front of anterior dorsocentral bristle. Epandrium relatively large and bulbous. Length 2.4-4.5mm ................................................................................... 160

-- Only setulae in front of anterior dorsocentral bristle. Epandrium small and slender. Length less than 3.0mm........... 161

160. Length 2.4-4.2mm. Acrostichal bristle absent. Notal stripes never joined basally (Fig. 86). First flagellomere yellow. Postpronotum yellow. Epandrium more spherical in shape (Figs 530, 531)................. S. bulbipenis spec. nov. (9.7) (in part)

-- Length 3.5-4.5mm. Acrostichal bristle present. Notal stripes of female usually joined basally (Fig. 158). Strong to faint infuscation present at base of arista on first flagellomere. Posterior half of postpronotum brown. Epandrium large and barrel-shaped (Figs 521, 522)....................................... S. vulgaris spec. nov. (9.64) (most specimens from Panama)

161. Notal stripes connected basally (Fig. 161). Wing dusky. Male cerci flush with distal margin of epandrium (Fig. 552)................................................................................ S. synapta spec. nov. (9.55) (in part)

-- Notal stripes usually separated at base; if connected, wing clear. Wing clear. Male cerci sunken below distal margin of epandrium............................................................................................. 162

162. Bristles brown. Scutellum entirely brown (Fig. 160). Notal spots sometimes connected basally. Fore tibia yellow. Surstylus approximately as high as epandrium (Fig. 423)................................... S. protea spec. nov. (9.48) (in part)

-- Bristles light brown. Scutellum usually yellow apically or much lighter than notal stripes (Fig. 164). Notal stripes never connected basally. Fore tibia light brown to brown. Surstylus small and rounded ( Figs 438, 439)............................................................................................. S. ochroapicalis spec. nov. (9.40) (in part)

163. Bristles black. Wing strongly clouded on anterior half or distal half............................................ 164

-- Bristles light brown to brown. Wing clear or lightly clouded anteriorly or apically................................. 165

164. Length 4.8mm. Anterior half of wing clouded from costa to the midpoint of the second radial cell. Fore tibia light brown in females. Frons brown laterally, or with short central stripe in front of ocellar tubercle (Fig. 151). Epandrium brown laterally and back of the head with one pair of stripes................................. S. aquilonaria spec. nov. (7.2) (in part)

-- Length 4.0mm. Distal half of wing darkly pigmented from costa to vein M 1. Fore and hind tibia brown. Frons yellow, excluding the ocellar tubercle (Fig. 163). Epandrium brown and back of head yellow............ S. melanothrix spec. nov. (9.38)

165. Parafacial, gena, and occiput silvery tomentose. Abdomen with thin yellow stripe extending from tergite 2 to the midpoint of tergite 4 (Fig. 155)............................................................ S. longipollex spec. nov. (9.34)

-- At least one of parafacial, gena, or occiput shiny. Abdomen without thin medial yellow stripe........................ 166

166. Length 3.5-4.5mm. Acrostichal bristle present. Posterior half of postpronotum brown (Fig. 158). Notal stripes sometimes touching basally in females. First flagellomere with strong to faint infuscation surrounding base of arista. Face often dark yellow or with orange tint. Epandrium large and barrel-shaped (Figs 521, 522).......... S. vulgaris spec. nov. (9.64) (in part)

-- Length 2.6-4.3mm, but usually shorter than 3.5mm. Acrostichal bristle absent. Postpronotum yellow or brown. First flagellomere entirely yellow or with faint spot at base of arista. Face entirely yellow. Epandrium small and saddle-shaped........ 167

167. Notal stripes connected in front of scutellum (Fig. 161). Fore and hind tibiae light brown in males, and only fore tibia brown in females................................................................. S. synapta spec. nov. (9.55) (in part)

-- Notal stripes entirely separated. Tibiae entirely yellow or only with fore tibia brown............................... 168

168. Postnotum entirely brown. First flagellomere sometimes with faint spot at base of arista. Wing clear. Surstylus approximately as high as epandrium and slightly tapered apically (Fig. 423)......................... S. protea spec. nov. (9.48) (in part)

-- Postnotum usually yellow, at least in part. First flagellomere entirely yellow. Wing lightly clouded on distal ¼. Surstylus small and rounded or forked................................................................................ 169

169. Acrostichal bristle absent. Fore tarsi light brown to brown. Postnotum entirely brown (Fig. 159). Surstylus rounded ( Figs 539, 540)............................................................... S. xanthotibialis spec. nov. (9.66) (in part)

-- Acrostichal bristle present. Fore tarsi yellow. Postnotum yellow (Fig. 63). Surstylus forked (Fig. 384).............................................................................................. S. dikros spec. nov. (8.5) (in part)

170. Length 1.5mm. Male terminalia small; ventral opening of epandrium constricted and surstyli small and directed inwards (Figs 345, 346)...................................................................... S. minima spec. nov. (8.12)

-- Length greater than 2.0mm. If terminalia as above, base of arista densely plumose and epiphallus + basiphallus large and heavily sclerotized ( S. atuberosa ).......................................................................... 171

171. Bristles dark brown. Epandrium large, bulbous, and yellowish-orange in colouration.. S. bulbipenis spec. nov. (9.7) (in part)

-- Bristles yellow to brown. Epandrium yellow and as wide as, or not much wider than, preceding tergites............... 172

172. One pair of lateral scutellar bristles...................................................................... 173

-- Two pairs of lateral scutellar bristles.................................................................... 177

173. Base of arista densely plumose (Fig. 65). Acrostichal bristle present. Face orange. Surstylus triangular and less than 1/3 height of epandrium ( Figs 186, 187)...................................................... S. atuberosa spec. nov. (1.2)

-- Arista sparsely plumose along entire length. Acrostichal bristle absent. Face yellow. Surstylus, if triangular, never less than 1/3 height of epandrium.................................................................................. 174

174. First radial and costal cells dark. Tergites 3 and 4 with one pair of small, brown, anterolateral spots, tergite 5 brown with a central yellow stripe, and tergite 6 black ( Fig. 52)......................................... S. notabina spec. nov. (4.5)

-- First radial and costal cells clear. Abdomen entirely yellow or with faded central stripe............................ 175

175. Length 5.0mm. Bristles light brown. Wing darkly clouded on distal 1/5 and around dm-cu ( Fig. 40). Fore tarsi brown....................................................................................... S. erwini spec. nov. (5.2)

-- Length less than 4.0mm. Bristles yellow. Wing clear. Fore tarsi yellow........................................ 176

176. Parafacial and gena shiny. Wing width less than 1/3 length. Occiput bulging.................... S. aprica spec. nov. (5.1)

-- Parafacial and gena pilose. Wing width more than 1/3 length. Occiput flat (level with gena).................................................................................................... S. hyalina spec. nov. (7.12) (in part)

177. Arista densely plumose on basal half. Gena approximately half height of eye............. S. gigantigena spec. nov. (9.24)

-- Arista with hairs sparsely arranged. Genal height no more than 1/3 height of eye................................ 178

178. Fore tibia brown, at least basally. Pregonite broad, only twice as long as wide (Fig. 499)........... S. lita spec. nov. (9.33)

-- Fore tibia yellow, occasionally light brown. Pregonite usually thin, with length three or more times width.............. 179

179. Anterior dorsocentral bristle half length of posterior bristle. Occiput usually shining. Surstylus as high as epandrium and curved posteriorly ( Figs 348, 349)................................................... S. jaliscana spec. nov. (8.9)

-- Anterior dorsocentral bristle not much shorter than posterior bristle. Occiput rarely pilose. Surstylus variable, but not as above................................................................................................... 180

180. Small to medium-length bristle present in front of anterior dorsocentral, distinctly longer and stronger than surrounding setulae............................................................................................... 181

-- Only weak setulae in front of anterior dorsocentral......................................................... 187

181. Parafacial and gena pilose; acrostichal bristle absent........................................................ 182

-- Parafacial and gena usually bare, but if pilose, then acrostichal bristle present.................................... 185

182. Wing clouded along anterodistal margin. Abdomen entirely yellow. Cerci sunkenbelow distal margin of epandrium ( Fig. 415). Surstylus small and rounded ( Fig. 414)............................................... S. ferruginea Czerny (9.19)

-- Wing clear. Abdomen sometimes with central stripe on tergites 2-4. Cerci usually flush with distal margin of epandrium; if sunken, surstylus approximately as high as epandrium (some S. protea , Fig. 423).................................. 183

183. Small bristle present in front of anterior dorsocentral. Parafacial, gena and occiput yellow. Male abdomen with wide median stripe on tergites 2-4 (Fig. 64). Surstylus bifid (Fig. 381)................................. S. schistos spec. nov. (8.16)

-- Only two dorsocentral bristles; only small setulae in front of anterior dorsocentral. Parafacial, gena and occiput white. Male abdomen yellow. Surstylus long, narrow and undivided..................................................... 184

184. Bristles yellow. Ocellar bristle well developed. Male abdomen yellow. Male fifth sternite without comb of bristles. Surstylus curved and of equal length along most of height (Fig. 351). Male cerci flush with distal margin of epandrium (Fig. 352).................................................................................... S. pubens spec. nov. (8.13)

-- Bristles brown. Ocellar bristle short and thin. Male abdomen brown in part. Male fifth sternite with comb of bristles. Surstylus subtriangular (Fig. 423). Male cerci sunken below distal margin of epandrium (Fig. 424)...................................................................................................... S. protea spec. nov. (9.48) (in part)

185. Bristles light brown. First flagellomere with faint spot lateral to base of arista. Parafacial and gena pilose. Surstylus narrow and high, with apex widened and incurved (Figs 491, 492)................................... S. malleata spec. nov. (9.37)

-- Bristles yellow. First flagellomere yellow. Parafacial and gena shiny. Surstylus not as above, and never as high as epandrium................................................................................................... 186

186. Acrostichal bristle present. Fore tarsi brown. Surstylus small and rounded ( Figs 447, 448)...... S. ganodes spec. nov. (9.22)

-- Acrostichal bristle absent. Fore tarsi yellow. Surstylus very narrow and strongly incurved (Figs 450, 451)....................................................................................... S. ankistrion spec. nov. (9.2) (in part)

187. Abdomen with strong, brown, central stripe on tergites 2-5 (Fig. 83). Surstylus rectangular (Figs 357, 358). Fifth sternite of male with one pair of posterolateral patches of bristles........................ S. quadristylus spec. nov. (8.14) (in part)

-- Abdomen yellow or with faded light brown stripe on one or two tergites; sometimes with posterior margins of tergites 2-6 brown. Surstylus variable, but never rectangular. Male fifth sternite evenly setose or with comb on posterior margin..... 188

188. Fore tarsi light brown. Surstylus minute and triangular ( Figs 470, 471)............... S. subtriangulina spec. nov. (9.54)

-- Fore tarsi or tibia sometimes brown with brownish tint. Surstylus variable, but usually larger and rounded............. 189

189. Surstylus truncate apically with posterodistal corner elongated (Figs 354, 355). Fore tibia sometimes with brown tint..................................................................................... S. theiodes spec. nov. (8.18)

-- Surstylus rounded apically. Fore tibia yellow.............................................................. 190

190. Ocellar tubercle yellow. Occiput pilose. Phallapodeme laterally flattened and carinate ( Fig. 458)... S. carina spec. nov. (9.9)

-- Ocellar tubercle light brown to brown. Occiput shiny. Phallapodeme rod-like.................................... 191

191. Abdomen with posterior margin of tergites 2-6 brown. Surstylus large and broadly rounded, narrowest subbasally, with numerous minute triangular bristles on inner-distal half and with elongate and incurved bristles apically (Figs 488, 489)..................................................................................... S. gorgopenis spec. nov. (9.23)

-- Abdomen yellow, or at most with stripe on 2 tergites. Surstylus not as above..................................... 192

192. Abdomen entirely yellow. Paraphallus long, tapering and spinulose apically, and with thumb well developed (Fig. 481). Distiphallus half length of phallapodeme............................................... S. incompta spec. nov. (9.29)

-- Light brown spot or stripe present on either tergite 3 or 4. Paraphallus small and ovate with thumb absent. Distiphallus less than 1/3 length of phallapodeme........................................................................ 193

193. Bristles light brown. Gena and parafacial pilose. Tergite 3 with light central spot. Phallapodeme with head atrophied and anterior face smooth ( Fig. 440).............................................. S. ochroapicalis spec. nov. (9.40) (in part)

-- Bristles yellow. Gena and parafacial shiny. Tergite 4 with light central spot. Phallapodeme with head unmodified and anterior face irregular (Fig. 455)........................................................ S. periglenes spec. nov. (9.44)