Key to New World Leptogenys

This key to North and South American species of Leptogenys is based on Lattke (2011) as modified by Lopez-Munoz et al. (2018) and Tozetto et al. (2022).

See also:
 * Leptogenys species groups (New World species)
 * Key to US Leptogenys species

1

 * Basal internal mandibular margin well separated from anterior clypeal margin with head in full-face view and mandibles closed, leaving distinct gap wider than mid-mandibular width (Fig. 1a) . . . . . 2


 * Basal internal margin of each mandible shuts tightly against clypeus, if gap is present it is narrow and not wider than mid-mandibular width (Fig. 1b) . . . . . 29

2
return to couplet #1
 * With head in full-face view hypostomal teeth distinctly visible, either wholly or partially (Fig. 2a, 2b) . . . . . 3


 * With head in full-face view hypostomal teeth not visible at all . . . . . 14

3
return to couplet #2
 * Petiole with an apical tooth or crest that overhangs at least part of posterior margin of node in lateral view (Fig. 3a) . . . . . 4


 * Posterior margin of node without overhanging tooth or crest (Fig. 3b) . . . . . 9

4
return to couplet #3
 * Petiolar node with acutely pointed apical tooth in lateral view (see images in couplets 5 and 6) . . . . . 5


 * Petiolar node with apical crest or blunt tooth (see images in couplet 8) . . . . . 7

5
return to couplet #4
 * Head in full-face view broad (CI > 0.90) with lateral margins distinctly diverging anteriorly . . . . . 6
 * Head narrower (CI < 0.90) with lateral margins sub-parallel or slightly diverging anteriorly . . . . . 5a

5a
return to couplet #5
 * Clypeal median lobe with 3–4 apical chaetae; mandible arched . . . . . Leptogenys bohlsi


 * Clypeal median lobe with 12 apical chaetae; mandible straight . . . . . Leptogenys elzasoares

6
return to couplet #5
 * Mandible gradually increasing in width towards apex . . . . . Leptogenys paraensis


 * Mandible of equal width throughout length . . . . . Leptogenys unistimulosa

7
return to couplet #4
 * Mandible with parallel basal and external margins, not expanding apicad . . . . . Leptogenys pubiceps (in part - also )


 * Mandible distinctly expanding apicad . . . . . 8

8
return to couplet #7
 * With head in full-face view mandible mostly straight except for strong basal arch; hypostomal tooth large, frequently extending behind mandible; petiolar node in dorsal view subquadrate . . . . . Leptogenys gatu


 * Mandible evenly arched, without strong basal arch; hypostomal tooth small, barely projecting anterad of clypeus; petiolar node in dorsal view elongate . . . . . Leptogenys punctaticeps (in part - also )

9
return to couplet #3
 * Body and head without standing pilosity . . . . . 10


 * Body and head with standing pilosity . . . . . 11

10
return to couplet #9
 * Mandible with parallel basal and external margins, not widening apicad; mandibular dorsum smooth and shining . . . . . Leptogenys maxillosa


 * Mandible gradually widening apicad; mandibular dorsum finely striolate . . . . . Leptogenys maya

11
return to couplet #9
 * WL > 2.5 mm; HW > 1.3 mm; body covered with abundant decumbent golden pilosity that partially obscures the underlying integument . . . . . 12


 * WL < 2.5 mm; HW < 1.3 mm; body with sparse erect pilosity never obscuring the underlying integument . . . . . 13

12
return to couplet #11
 * Head in full-face view with evenly arched mandible, with subparallel external and basal margins; body black . . . . . Leptogenys chamela


 * Mandible with an approximately straight external margin and convex basal margin, apically widening; body ferruginous . . . . . Leptogenys sonora

13
return to couplet #11
 * Third antennal segment > 2 × as long as wide; clypeus in cephalic full-face view with a prominent median laminate lobe, anterolaterally bordered by narrow lamella . . . . . Leptogenys montuosa


 * Third antennal segment < 2 × as long as wide; clypeus with modest median lobe of thick cuticle, not anterolaterally thin and lamellate . . . . . Leptogenys arcuata (in part - also )

14
return to couplet #2
 * Petiole in lateral view without dorsoposterior tooth or point (Fig. 14a) . . . . . 15


 * Petiole with a dorsoposterior tooth, blunt point or crest that usually overhangs the posterior petiolar margin (Figs. 14b ) . . . . . 25

15
return to couplet #14
 * Petiolar node triangular in lateral view . . . . . Leptogenys panops


 * Petiolar node subquadrate in lateral view (compare petiolar node in profile view of panops above to profile view of workers in couplets below) . . . . . 16

16
return to couplet #15
 * Cephalic dorsum between and posterad of eyes mostly densely sculptured (Fig 16a) . . . . . 17


 * Cephalic dorsum between and posterad of eyes mostly smooth and shining, at most with sparse piligerous punctulae (Fig 16b) . . . . . 21

17
return to couplet #16
 * Dorsum of head and mesosoma opaque; dorsum of mesosoma in lateral view with no standing hairs . . . . . 18


 * Dorsum of head and mesosoma with shining cuticle; dorsum of mesosoma with abundant standing hairs . . . . . 19

18
return to couplet #17
 * Mandible with subparallel basal and external margins; head broad in full-face view; ocular diameter > 1/3 the length of lateral cephalic margin . . . . . Leptogenys wheeleri


 * Mandible widens apically; head elongate in full-face view; ocular diameter 1/4 of lateral cephalic margin . . . . . Leptogenys ixta

19
return to couplet #17
 * Head in full-face view wider than long; mandible of even width from base to apex . . . . . Leptogenys donisthorpei


 * Head longer than wide, mandible wider apically than basally . . . . . 20

20
return to couplet #19
 * Median clypeal lobe with a single apical point . . . . . Leptogenys peninsularis


 * Median clypeal lobe bifurcate . . . . . Leptogenys bifida

21
return to couplet #16
 * Head in full-face view with brief anteromedian clypeal lobe, not longer than basal width (Fig. 21a) . . . . . 22


 * Head with clypeal lobe longer than basal width (Fig. 21b) . . . . . 23

22
return to couplet #21
 * Petiolar node in lateral view with continuously convex anterodorsal margin; node posterior margin weakly convex . . . . . Leptogenys santacruzi


 * Petiolar node in lateral view with vertical anterior margin and convex dorsal margin; posterior margin vertical . . . . . Leptogenys arcuata (in part - also )

23
return to couplet #21
 * Petiolar node wider than long in dorsal view with sub-parallel anterior and posterior margins; head, mesosoma and petiole with numerous punctae; clypeal lobe broadly triangular . . . . . Leptogenys toxeres


 * Petiolar node longer than wide with a convex anterior margin and a transverse, straight posterior margin; body mostly smooth and shining with sparse minute punctulae; clypeal lobe slender . . . . . 24

24
return to couplet #23
 * Width of third antennal segment < 1/2 its length; length of clypeal median lobe less than width of third antennal segment; WL > 1.3 mm . . . . . Leptogenys gagates


 * Width of third antennal segment > 1/2 its length; length of clypeal median lobe more than width of third antennal segment; WL < 1.3 mm . . . . . Leptogenys langi (in part - also )

25
return to couplet #14
 * Mandible parallel-sided in cephalic full-face view; cephalic dorsum usually smooth and shining with scattered punctulae . . . . . Leptogenys pubiceps (in part - also )


 * Mandible widening apicad; cephalic dorsum variable, usually punctate with striae at least on anterior region close to antennal insertions, or mostly smooth and shining . . . . . 26

26
return to couplet #25
 * Head longer than wide in full-face view; body lacking iridescence; petiolar node with crest or modest apical tooth (Fig. ) . . . . . 27


 * Head wider than long; body with purple-blue iridescence; petiolar node with large apical tooth . . . . . Leptogenys ingens

27
return to couplet #26
 * In cephalic full-face view lateral clypeal lobe prominent, appearing as distinct lobe or blunt tooth next to median clypeal lobe posterior margin of the petiolar node broadly concave in lateral view (Figs. ) . . . . . Leptogenys carbonaria (in part - also )


 * Lateral clypeal lobe inconspicuous, not appearing as distinct lobe or blunt tooth next to median clypeal lobe (Fig. ); posterior margin of the petiolar node sinuate . . . . . 28

28
return to couplet #27
 * Cephalic dorsum mostly smooth and shining; apex of petiolar node with distinct short, slender tooth . . . . . Leptogenys amazonica


 * Cephalic dorsum mostly punctate; apex of petiolar node with blunt crest, not shaped as a distinct tooth . . . . . Leptogenys punctaticeps (in part - also )

29
return to couplet #1
 * Petiolar node mostly triangular and elongate in lateral view, with a sloping, and fairly straight, anterior margin and a vertical posterior margin; if distinct vertical anterior margin is present, it is < 1/4 the height of posterior margin (Fig. ) . . . . . 30


 * Node not triangular, generally semi-quadrate with vertical, subparallel, anterior and posterior margins, and a more or less horizontal dorsal margin (rarely angular), the anterior margin is > 1/4 the length of the posterior margin (Fig. ); less commonly the node may be dome-shaped or with a continuously convex anterodorsal margin and more or less vertical posterior margin. (Fig. ) . . . . . 39

30
return to couplet #29
 * Propodeal dorsum mostly sculpted, either striate or punctulate (Fig. 30a) . . . . . 31


 * Propodeal dorsum mostly smooth and shining (Fig. 30b) . . . . . 34

31
return to couplet #30
 * Petiole in lateral view with a distinct dorso-apical tooth (Fig. ); anteromedian clypeal process flanked by lateral lobes near apex . . . . . Leptogenys tiobil


 * Petiole never dentate, dorso-apically rounded or with a sharp angle at most (Figs. ); clypeal process regularly triangular at apex (Figs. ) . . . . . 32

32
return to couplet #31
 * Pronotal disc rugose; body black without blue opalescence . . . . . Leptogenys socorda


 * Pronotal disc punctulate, or smooth and shining; body frequently with blue opalescence . . . . . 33

33
return to couplet #32
 * Pronotal disc mostly smooth and shining with sparse punctulae; propodeal dorsum transversely striate; mandible widening apicad with low jagged denticles on chewing margin . . . . . Leptogenys famelica


 * Pronotal disc densely punctulate; propodeal dorsum densely punctulate, striae mostly limited to declivity; mandible of equal width apicad, chewing margin edentate . . . . . Leptogenys imperatrix

34
return to couplet #30
 * Mesosoma in lateral view with dorsal margin mostly straight, metanotal groove shallow (Fig. ) . . . . . 35


 * Mesosoma in lateral view with dorsal margin forming two distinct convexities separated by broad metanotal groove (Fig. ) . . . . . 37

35
return to couplet #34
 * Anterior margin of petiolar node in dorsal view < 1/2 the width of posterior margin, node elongate=>36 . . . . . 36


 * Anterior margin of petiolar node ≥ 1/2 the width of posterior margin . . . . . Leptogenys pucuna

36
return to couplet #35
 * Foretibial apex with transparent cuticular lobe next to strigil; head subrectangular in full-face view; eye flattened, barely convex; constriction between abdominal segments III and IV weak . . . . . Leptogenys gaigei


 * Foretibial apex without transparent lobe next to strigil; head elongate in full-face view; eye broadly convex; constriction between abdominal segments III and IV strong . . . . . Leptogenys vogeli

37

 * Propodeal declivity in lateral view ending in an abrupt overhang formed by propodeal lobes (Fig. 40B); mandible expanding apicad of mid-length; body with blue iridescence (southeastern Brazil) . . . . . . Leptogenys luederwaldti


 * Propodeal lobes in lateral view absent or low and weakly developed (Fig. 71B), shaped either rounded or bluntly triangular, never forming an overhang; mandible not expanding apicad of mid-length; body lacking any iridescence . . . . . 38

38
return to couplet #37
 * Petiolar node in lateral view shaped as elongate triangle, with brief vertical anterior margin; masticatory margin of mandible meeting internal angle at an abrupt, almost perpendicular angle; foretibial apex with a transparent cuticular lobe next to strigil (Panama—eastern Peru) . . . . . . Leptogenys cuneata


 * Petiolar node in lateral view not elongate, anterior and dorsal margins form a continuous convexity; masticatory and internal mandibular margins meeting through blunt angle or convexity; foretibial apex without a transparent cuticular lobe next to strigil . . . . . 38a

38a
return to couplet #38
 * Head subquadrate (CI 0.76–0.78), median clypeal process shaped as short rounded lobe with 3–4 seta on apex; mandible wid-est at mid length; propodeum rounded and unarmed (eastern Peru) . . . . . . Leptogenys peruana


 * Head in dorsal view elongate (CI 0.56–0.61), median clypeal process triangular, evenly tapering anterad, apex lacking setae; mandible in dorsal view of uniform width; propodeal declivity with low, but distinct, lateral lobes or teeth (southeastern Brazil) . . . . . 38b

38b
return to couplet #38a
 * Size larger (WL 2.91–2.94 mm); propodeal dorsum smooth and shining with sparse piligerous punctulae; propodeal lobe in lat-eral view triangular with jagged dorsal margin . . . . . . Leptogenys academica


 * Size smaller (WL 2.47–2.72 mm); propodeal dorsum mostly smooth and shining with scattered patches of shallow transverse rugulae and scattered shallow punctae; propodeal lobe shaped as low rounded lobe without jagged margins . . . . . . Leptogenys carioca

39
return to couplet #29
 * Petiolar node in lateral view approximately dome-shaped, with the highest part close to the mid-distance of the node; anterior margin convex or with a blunt angle between the anterior and dorsal margins . . . . . 40


 * Petiolar node subquadrate, with vertical, subparallel, anterior and posterior margins, and horizontal or convex dorsal margin; or the anterodorsal margin is convex and posterior margin vertical . . . . . 43

40
return to couplet #39
 * Mandible triangular; head, mesosoma, and petiole with extensive sculpturing . . . . . Leptogenys honduriana


 * Mandible slender and semi-falcate; head, mesosoma, and petiole mostly smooth and shining . . . . . 41

41
return to couplet #40
 * Small species: HW < 0.80 mm; WL < 1.76 mm . . . . . Leptogenys reggae


 * Larger species: HW > 0.80 mm; WL > 1.76 mm . . . . . 42

42
return to couplet #41
 * Head in full-face view with eyes at mid-cephalic length; basal and masticatory mandibular margins separated by blunt angle . . . . . Leptogenys linda


 * Eyes closer to mandibular insertion than to mid-cephalic length; basal and masticatory mandibular margins joined through broad curve . . . . . Leptogenys tama

43
return to couplet #39
 * Dorsum of head and mesosoma with extensive sculpturing . . . . . 44


 * Dorsum of head and mesosoma mostly smooth and shining with sparse punctulae . . . . . 52

44
return to couplet #43
 * Petiolar node in lateral view with posterodorsal blunt point that overhangs posterior petiolar margin . . . . . Leptogenys carbonaria (in part - also )


 * Petiolar node without posterodorsal point or denticle . . . . . 45

45
return to couplet #44
 * Postpetiolar tergite opaque and densely punctate, the space surrounding each puncture equal to or less than the diameter of each puncture . . . . . 46


 * Postpetiolar tergite mostly smooth and shining with sparse punctulae, the space surrounding each puncture many times greater than the diameter of each puncture . . . . . 48

46
return to couplet #45
 * Mesosoma in lateral view with no standing hairs on dorsum . . . . . Leptogenys quirozi


 * Mesosoma with 10 or more standing hairs on dorsum . . . . . 47

47
return to couplet #46
 * Clypeal anterior margin in cephalic full-face view with strongly developed lateral clypeal lobes at each side of median lobe . . . . . Leptogenys foraminosa


 * Clypeus with anterior margin converging evenly to median lobe, lateral clypeal lobes indistinct . . . . . Leptogenys sianka

48
return to couplet #45
 * Mandible not widening apicad; basal and external margins mostly semi-parallel . . . . . 49


 * Mandible usually widening apicad, becoming triangular, or unusually shaped . . . . . 50

49
return to couplet #48
 * Scape surpasses posterior cephalic margin by ≥ 1/3 its length; second funicular segment almost 2 × as long as third segment; mandibular dorsum mostly smooth, with weak striolae at most . . . . . Leptogenys volcanica


 * Scape surpasses posterior cephalic margin by ≤ 1/4 its length; second funicular segment slightly longer than third segment; mandibular dorsum mostly striate . . . . . Leptogenys linearis (in part - also )

50
return to couplet #48
 * Mandible triangular; median clypeal lobe ending in a blunt point . . . . . 51


 * Mandible with large preapical rounded notch; median clypeal lobe apically truncate . . . . . Leptogenys oaxaca

51
return to couplet #50
 * Mesosoma wider than long in dorsal view . . . . . Leptogenys elongata


 * Mesosoma longer than wide in dorsal view . . . . . Leptogenys manni

52
return to couplet #43
 * Apical half of mandible increasing in width giving mandible a triangular or semi-triangular aspect (Fig. ) . . . . . 53


 * Apical half of mandibular dorsal surface of uniform width; masticatory margin not expanded into semi-triangular shape (Fig. ) . . . . . 60

53
return to couplet #52
 * Propodeum with lateral tooth or lobe; mandibular masticatory margin edentate . . . . . 54


 * Propodeum without a trace of lobe or tooth, laterally rounded; mandible with preapical tooth or denticles along masticatory margin . . . . . 57

54
return to couplet #53
 * Mandible elongate, basal margin > 2 × longer than masticatory margin . . . . . 55


 * Mandible triangular, lengths of basal and masticatory margin approximately equal . . . . . 56

55
return to couplet #54
 * Large ant, WL > 2.3 mm; mandible does not shut tight against clypeus (Fig. ), meso- and metapleura with variable amounts of striae . . . . . Leptogenys ciliata


 * Small ant, WL < 2.3 mm; mandible shuts tight against clypeus (Fig. ); meso- and metapleura smooth and shining . . . . . Leptogenys consanguinea

56
return to couplet #54
 * Compound eye covers almost 1/3 the length of lateral cephalic margin; eye dorsolaterally placed on head . . . . . Leptogenys nigricans


 * Compound eye covering ≤ 1/4 lateral cephalic margin; eye placed laterally on head . . . . . Leptogenys deborae

57
return to couplet #53
 * Length of second antennal segment 1/2 of segment III; petiolar node elongate in dorsal view, width < 85% of length . . . . . 58


 * Length of second antennal segment > 1/2 of segment III; petiolar node subquadrate, width > 85% of length . . . . . 59

58
return to couplet #57
 * Mesonotum wider than long; mesopleural lobe shaped low and convex . . . . . Leptogenys phylloba


 * Mesonotum longer than wide; mesopleural lobe projects laterally as small fin or wing . . . . . Leptogenys pinna

59
return to couplet #57
 * Eye length > oculomalar distance; masticatory margin of mandible denticulate to crenulate . . . . . Leptogenys serrata


 * Eye length < oculomalar distance; masticatory margin of mandible edentate except for single preapical tooth . . . . . Leptogenys pittieri

60
return to couplet #52
 * Compound eyes situated dorsolaterally with head in full-face view; not only is whole dorsal ocular perimeter observable, but also part of ventral ocular perimeter, or only a small part or none of the dorsal ocular margin extends beyond the lateral cephalic margin (Fig. ) . . . . . 61


 * Compound eyes extended more laterally in full-face view of head; the ventral ocular perimeter is not visible, and all or most of the dorsal ocular margin extends beyond the lateral cephalic margin (Fig. ) . . . . . 65

61
return to couplet #60
 * Dorsal mandibular surface mostly striate; dorsal mesosomal margin continuously curved in lateral view; clypeal apex with at least two stout setae . . . . . Leptogenys linearis (in part - also )


 * Mandibles mostly smooth and shining with sparse punctures; dorsal mesosomal margin divided by deep or shallow metanotal groove into convex promesonotal margin, and convex or flat propodeal margin; clypeal apex lacking stout setae . . . . . 62

62
return to couplet #61
 * Width of anterior petiolar margin ≤ 1/2 width of posterior margin in dorsal view . . . . . 63


 * Anterior margin of petiole > 1/2 width of posterior margin in dorsal view . . . . . 64

63
return to couplet #62
 * Mesonotum 3 × wider than long in dorsal view; node with anterior margin 1/2 width of posterior margin in dorsal view . . . . . Leptogenys rasila


 * Width of mesonotum ≤ 2 × its length; anterior margin of node < 1/2 width of posterior margin . . . . . Leptogenys iheringi (in part - also #75)

64
return to couplet #62
 * HL < 1.10 mm, WL < 1.70 mm; width of third antennal segment > 1/2 its length . . . . . Leptogenys amu


 * HL > 1.10 mm, WL > 1.70 mm; width of third antennal segment approximately 1/4 its length . . . . . Leptogenys crudelis

65
return to couplet #60
 * With head in full-face view, the midpoint of compound eye closer to mandibular insertion than to mid-length of lateral cephalic margin (Fig. ) . . . . . 66


 * With head in full-face view, the midpoint of compound eye exactly at, or closer to mid-length of lateral cephalic margin than to mandibular insertion (Fig. ) . . . . . 68

66
return to couplet #65
 * Head in full-face view with semiparallel lateral margins; abdominal tergites III and IV mostly smooth and shining with sparse punctulae . . . . . 67


 * Head with anteriorly diverging lateral margins; abdominal tergites III and IV punctate to varying degree . . . . . Leptogenys foveonates

67
return to couplet #66
 * Clypeal anterior margin in cephalic full-face view with gradually tapering median lobe; in lateral view propodeum edentate, with low triangular lobes at most . . . . . Leptogenys ritae


 * Clypeal anterior margin with abruptly projecting slender median lobe; propodeum with 2 distinct teeth . . . . . Leptogenys corniculans

68
return to couplet #65
 * Median clypeal lobe elongate and slender in cephalic full-face view (Fig. ) . . . . . 69


 * Median clypeal lobe broader, triangular with a pointed, blunt or truncate apex (Figs. ) . . . . . 71

69
return to couplet #68
 * Compound eye large (CI > 0.30), covering almost 1/3 length of lateral cephalic margin . . . . . Leptogenys mavaca


 * Compound eye smaller (CI < 0.30), covering ≤ 1/4 length of lateral cephalic margin . . . . . 70

70
return to couplet #69
 * Scape extending beyond the posterior cephalic margin by > 1/3 length; petiole with prominent anterior shelf in lateral view, almost 1/2 length of node . . . . . Leptogenys cracens


 * Scape extending beyond the posterior cephalic margin by about 1/4 length; petiole without prominent anterior shelf, < 1/4 length of the node . . . . . Leptogenys langi (in part - also )

71
return to couplet #68
 * Median clypeal lobe with subquadrate or bluntly angular apex, sometimes with apical lamellate denticle (Fig. ) . . . . . 72


 * Clypeus in cephalic full-face view with median lobe evenly tapering anterad to pointed or rounded apex (Fig. ) . . . . . 73

72
return to couplet #71
 * Mesometapleural suture broad, scrobiculate, widening anterad; cross-section of petiolar node at mid-length convex; width of second funicular segment more than 1/2 its length . . . . . Leptogenys cordoba


 * Mesometapleural suture fine, smooth, not scrobiculate; cross-section of petiolar node at mid-length V- shaped; width of second funicular segment less than 1/3 its length . . . . . Leptogenys glabra

73
return to couplet #71
 * Petiolar node elongate in dorsal view, anterior margin at most half as wide as posterior margin . . . . . 74


 * Petiolar node subquadrate in dorsal view, anterior margin more than half as wide as posterior margin . . . . . 78

74
return to couplet #73
 * Propodeum with distinct lobes or denticles (Figs. 11B, 45B) . . . . . 75


 * Propodeum without teeth or denticles, at the most a low lobe may be present posterad of each propodeal spiracle (Figs. ) . . . . . 77

75
return to couplet #74
 * Petiolar node with anterior and dorsal margins forming continuous convexity in lateral view; postero-dorsal propodeal margin evenly convex until apex of propodeal lobe in lateral view; WL > 1.4 mm . . . . . Leptogenys iheringi (in part - also #63)


 * Node with distinctly vertical anterior margin and convex dorsal in lateral view; posterodorsal propodeal margin convex until base of propodeal tooth, tooth abruptly projecting; WL < 1.4 mm . . . . . 76

76
return to couplet #75
 * Scape surpasses posterior cephalic margin by one apical diameter; width of third antennal segment > 1/2 its length; body without iridescence . . . . . Leptogenys gorgona


 * Scape surpasses posterior cephalic margin by at least 3 apical widths; width of third antennal segment ≤ 1/2 its length; body usually with blue iridescence . . . . . Leptogenys melena

77
return to couplet #74
 * Compound eye situated in the middle of the lateral cephalic margin with head in full-face view; width of petiolar posterior margin > 3/4 length of petiole . . . . . Leptogenys antillana


 * Compound eye situated anterad of midpoint of lateral cephalic margin; width of petiolar posterior margin < 3/4 length of petiole . . . . . Leptogenys quadrata

78
return to couplet #73
 * Propodeum with distinct denticles or lobes (Fig. ) . . . . . 79


 * Propodeum unarmed, without teeth or denticles, at most low swelling may be present next to each propodeal spiracle (Fig. ) . . . . . 85

79
return to couplet #78
 * Length of third antennal segment equal to or more than twice its apical width . . . . . 80


 * Length of third antennal segment less than twice its apical width . . . . . 82

80
return to couplet #79
 * Compound eye large, occupying at least 1/3 lateral cephalic margin in cephalic full-face view . . . . . Leptogenys minima


 * Compound eye smaller, occupying ≤ 1/4 lateral cephalic margin (Fig. ) . . . . . 81

81
return to couplet #80
 * Mesonotum transverse in dorsal view, at least 3 × wider than long; metanotal groove smooth . . . . . Leptogenys quiriguana


 * Mesonotum oval in dorsal view, 2 × as long as broad; metanotal groove scrobiculate . . . . . Leptogenys australis

82
return to couplet #79
 * Compound eye small, approximately 4 ommatidia across, OI < 0.15 . . . . . Leptogenys rufa


 * Compound eye larger, at least 8 ommatidia across, OI > 0.15 (Fig. ) . . . . . 83

83
return to couplet #82
 * Basal mandibular margin with 3 – 2 stiff setae basad; compound eye mostly flat . . . . . Leptogenys guianensis


 * Basal mandibular margin with sparse pilosity, none standing out as setae or noticeably thick; compound eye weakly convex (Fig. ) . . . . . 84

84
return to couplet #83
 * Mandible with basal and masticatory margin joined by continuously curved flange in dorsal view; propodeal spiracle elongate . . . . . Leptogenys yocota


 * Mandible with basal and masticatory margin separated by blunt angle; propodeal spiracle broadly oval . . . . . Leptogenys orchidioides

85
return to couplet #78
 * Mesonotum narrow and parallel sided, with straight anterior and posterior margins in dorsal view; mandible with a sinuate basal margin in cephalic full-face view, with a basal convexity and apical concavity . . . . . 86


 * Mesonotum not parallel sided, with at least one curved margin; basal mandibular margin not sinuate, either mostly convex, or basally convex and apically straight . . . . . 87

86
return to couplet #85
 * Apical width of the third antennal segment ≥ 3/4 its length . . . . . Leptogenys pusilla


 * Apical width of third antennal segment ≤ 2/3 its length . . . . . Leptogenys josephi

87
return to couplet #85
 * Length of third antennal segment ≥ 2 × its apical width; compound eye larger (OI: 0.23 – 0.27) . . . . . Leptogenys erugata


 * Length of third antennal segment < 2 × its apical width; compound eye smaller (OI: 0.18 – 0.20) . . . . . Leptogenys kiche