Syneches Walker

Menezes, Isis Sá & Ale-Rocha, Rosaly, 2016, Revision of the Amazonian species of Syneches Walker (Diptera, Hybotidae, Hybotinae), Zootaxa 4103 (5), pp. 401-442 : 403-404

Key to Amazonian species of Syneches Walker

1 Prosternum wide ( Fig. 1 ).............................................................................. 2

- Prosternum narrow ( Fig. 2 )............................................................................ 5

2 Femora slender; postpedicel long, 3.5 times longer than length of scape and pedicel combined; scutum with a quadrangular dark brown dorsal stain on anterior 1/3..................................... S. longiflagellatus Ale-Rocha & Vieira

- All femora swollen; postpedicel short, equal to or slightly longer than length of scape and pedicel combined; scutum without stain on anterior 1/3................................................................................... 3

3 Hind femur as dilated as mid femur; hind femur yellow with apex brown; prescutellar disc with mixed golden and gray pruinescence..................................................................... S. rafaeli Ale-Rocha & Vieira

- Hind femur distinctly more dilated than mid femur; hind femur brown with apex yellow, or with a preapical yellow ring; prescutellar disc with pale golden or gray pruinescence......................................................... 4

4 Pterostigma subquadrangular ( Fig. 115 ); mid femur with AV row of long and stout setae along the entire length.................................................................................................. S. walkeri Smith

- Pterostigma elongate, sometimes fading distally, becoming glassy at apex of cell r1 ( Fig. 107 ); mid femur with AV row of long and stout setae at basal half........................................................... S. curvipes (Fabricius)

5 Ocellar triangle flat, not protuberant..................................................................... 6

- Ocellar triangle distinctly protuberant.................................................................... 8

6 Fore and mid femora brown, with yellow apex; hind tibia yellow with brown medial ring; pterostigma small and subrounded, located at end of vein R1 ( Fig. 105 )...................................................... S. applanatus sp. nov.

- Fore and mid femora yellow; hind tibia yellow with apical 1/2 to 2/3 brown; pterostigma oval or quadrangular, filling up the apex of cell r1 ( Fig. 111 )............................................................................... 7

7 Vein R2+3 with apex abruptly bent around pterostigma, joining the Costa at a right angle; pterostigma subquadrangular ( Fig. 111 ); hind femur dark brown............................................................... S. manaos Smith

- Vein R2+3 with apex slightly curved upward, in acute angle with Costa; pterostigma oval ( Rafael & Ale-Rocha 1995, fig. 64); hind femur brown with basal 1⁄3 to 1/2 yellow................................................. S. repletus Bezzi

8 Scutum low, flattened, about half of the height of mesopleuron; pterostigma elongate, starting at apex of vein R1, not filling the apex of cell r1 (ex. Fig. 103 )............................................................................ 9

- Scutum high, rounded or pyramidal, equal or higher than height of mesopleuron; pterostigma not as above, if elongate then the scutum is high, globose and the wing is brown............................................................ 12

9 Midleg yellow except tarsomeres 3–5 brown............................................................. 10

- Midleg brown......................................................................... S. fuscescens Bezzi

10 Scutum brown; wing brown tinged, slightly paler on posterior margin and darker on costal region up to the apex ( Fig. 108 ) 11

- Scutum yellow with bow-shaped dark brown band anteriorly; wing with large brown infuscation on distal third extending to upper half of cell m1 ( Rafael & Ale-Rocha 1995, fig. 62)........................................ S. dichrous Bezzi

11 Hind leg pale brown except femur brown medially, tibia and tarsomeres 3–5 dark brown; pterostigma narrow, small, not filling the apex of cell r1 ( Fig. 103 ); hypandrium with apical 1/3 tapered, cleft apically; phallus slender with narrow apex; postgonite slender, longer than phallus, apex hook-shaped ( Fig. 4 )..................................... S. amazonicus sp. nov.

- Hind leg brown, except coxa, trochanter and basal 1/3 of femur yellow; pterostigma large, filling 2/3 of the apex of r1 ( Fig. 108 ); hypandrium slightly narrowed towards base, distal margin triangular; phallus robust, tapered distally, with rounded apex and sclerotized lateral protuberance; postgonite slender and shorter than phallus ( Fig. 41 ).......... S. equatoriensis sp. nov.

12 Scutum pyramidal, higher than mesopleuron and pleura brown, if rounded and same height as mesopleuron then pleura totally yellow; small species, most do not exceed 3.5 mm ......................................................... 13

- Scutum rounded, same height as mesopleuron; medium to large species, over 3.8 mm ............................. 20

13 Scutum pyramidal with reddish brown or gray pruinescence on prescutellar disc; pterostigma hyaline or brown tinged; antenna with scape and pedicel brown......................................................................... 14

- Scutum rounded with prescutellar disc covered with dense, silvery pruinescence; wing with inconspicuous pterostigma ( Fig. 112 ); antenna with scape and pedicel yellow................................................. S. moraballi Smith

14 Tibiae yellow; scutum with reddish brown pruinescence..................................... S. pyramidatus Bezzi

- Tibiae brown to dark brown, with base and apex yellow; scutum with gray pruinescence on prescutellar disc........... 15

15 Wing with pterostigma divided into two stains or pale spots, one at end of R1 and other in the extremity of R2+3 (ex. Figs 104, 112 ).............................................................................................. 16

- Wing with pterostigma in the end of R1 or inconspicuous ( Fig. 106 )........................................... 18

16 Vein R2+3 with apex abruptly bent to the Costa ( Fig. 104 ); antenna dark brown..................... S. angulatus sp. nov.

- Vein R2+3 with apex gradually curved upwards ( Fig. 112 ); antenna brown, except apex of postpedicel yellow........... 17

17 Palpus brown; hind femur slightly more dilated than mid and fore femora; hypandrium rounded apically, with a pair of apical median setae inserted next to each other ( Ale-Rocha & Vieira 2008, fig. 30)................ S. vidali Ale-Rocha & Vieira

- Palpus yellow; hind femur more slender than mid and fore femora; hypandrium with apex slightly concave between the pair of long and widely separated setae ( Fig. 60 )................................................. S. maculosum sp. nov.

18 Cell R1 narrow, particularly apically; pterostigma slightly opaque ( Rafael & Ale-Rocha 1995, fig. 65); epandrial lamella with sharpened apex......................................................................... S. obeliscus Bezzi

- Cell R1 widened, particularly apically (ex. Fig. 106 ); pterostigma hyaline or brown fading distally; epandrial lamella with a small preapical dorsal protuberance ( Fig. 28 )............................................................. 19

19 Pterostigma small, triangular ( Rafael & Ale-Rocha 1995, fig. 66); postpedicel rounded, 2/3 of combined length of scape and pedicel; distal margin of hypandrium flat.................................................... S. annulipes Bezzi

- Pterostigma hyaline ( Fig. 106 ); postpedicel oval, equal to combined length of scape and pedicel; distal margin of hypandrium with shallow median concavity forming two rounded lateral lobes ( Fig. 27 )....................... S. bilobatus sp. nov.

20 Pterostigma large, rectangular, at end of R1 and one dark spot at apex of R2+3 ( Fig. 115 ; Rafael & Ale-Rocha 1995, fig. 63)..................................................................................................... 21

- Pterostigma elongated ( Figs 109, 116 )................................................................... 22

21 Antenna yellow; legs yellow except hind leg with distal half of femur brown, tibia and tarsomeres brown; hind tarsomere 1 slender............................................................................ S. stigmaticalis Bezzi

- Antenna with scape and pedicel dark brown and pale yellow postpedicel; legs yellow with brown rings on femora and tibiae; hind tarsomere 1 slightly dilated.......................................................... S. striatus sp. nov.

22 Femora slender; sub-hyaline with brown pterostigma ( Fig. 109 ; Ale-Rocha & Vieira 2008, fig. 37).................. 23

- Fore femur enlarged; wing brown with dark brown pterostigma ( Fig. 114 )....................... S. tenebricus sp. nov.

23 Hind tibia swollen apically; hind tarsomere 1 dilated; hypandrium trapezoidal distally ( Ale-Rocha & Vieira 2008, fig. 9)................................................................................ S. jauensi Ale-Rocha & Vieira

- Hind tibia slender; hind tarsomere 1 slender; hypandrium rounded distally, with slightly narrowed apex ( Fig. 48 ).................................................................................................. S. exilis sp. nov.

Figures

FIGURES 1 – 2. Prosternum in Syneches (frontal view): 1, prosternum wide, Syneches curvipes; 2, prosternum narrow, Syneches moraballi. Scale = 0.5 mm. Abbreviations: CC—cervical cavity, CERV SCL—cervical sclerite, CX—coxa, PREPM—proepimeron, PREPST—proepisternum, PRN—pronotum, PPRN LB—postpronotal lobe, PRST—prosternum.

FIGURES 103 – 117. Wings of Amazonian species of Syneches: 103, S. amazonicus sp. nov.; 104, S. angulatus sp. nov.; 105, S. applanatus sp. nov.; 106, S. bilobatus sp. nov.; 107, S. curvipes; 108, S. equatoriensis sp. nov.; 109, S. exilis sp. nov.; 110, S. maculosum sp. nov.; 111, S. manaos; 112, S. moraballi; 113, S. striatus sp. nov.; 114, S. tenebricus sp. nov.; 115, S. walkeri; 116, S. sp. 1; 117, S. sp. 2. Scale = 0.5 mm.

FIGURES 3 – 9. Syneches amazonicus sp. nov. (paratype). Male terminalia: 3, epandrium, cerci and hypoproct (dorsal view); 4, hypandrium, postgonite and phallus (ventral view); 5, epandrial lamella (lateral view); 6, tergite 8; 7, sternite 8. Female terminalia: 8, ventral view; 9, dorsal view. Scale = 0.2 mm. Abbreviations: tg—tergite, st—sternite, cerc—cerci, epandepandrium, hypd—hypandrium, hyprct—hypoproct, ph—phallus, pgont—postgonite.

FIGURES 40 – 46. Syneches equatoriensis sp. nov. (paratype). Male terminalia: 40, epandrium, cerci and hypoproct (dorsal view); 41, hypandrium, postgonite and phallus (ventral view); 42, right epandrial lamella (lateral view); 43, tergite 8; 44, sternite 8. Female terminalia: 45, ventral view; 46, dorsal view. Scale = 0.2 mm.

FIGURES 59 – 65. Syneches maculosum sp. nov. (paratype). Male terminalia: 59, epandrium, cerci and hypoproct (dorsal view); 60, hypandrium, postgonite and phallus (ventral view); 61, left epandrial lamella (lateral view); 62, tergite 8; 63, sternite 8. Female terminalia: 64, ventral view; 65, dorsal view. Scale = 0.2 mm.

FIGURES 26 – 32. Syneches bilobatus sp. nov. (paratype). Male terminalia: 26, epandrium, cerci and hypoproct (dorsal view); 27, hypandrium, postgonite and phallus (ventral view); 28, right epandrial lamella (lateral view); 29, tergite 8; 30, sternite 8. Female terminalia: 31, ventral view; 32, dorsal view. Scale = 0.2 mm.

FIGURES 47 – 53. Syneches exilis sp. nov. (paratype). Male terminalia: 47, epandrium, cerci and hypoproct (dorsal view); 48, hypandrium, postgonite and phallus (ventral view); 49, right epandrial lamella (vista lateral); 50, tergite 8; 51, sternite 8. Female terminalia: 52, ventral view; 53, dorsal view. Scale = 0.2 mm.