The dichotomous key is based on female morphological characters. Geographical distribution is summarized.

1. Metasoma tergum I more enlarged, wider than long or as wide as longe in dorsal view, dilated abruptly in lateral view 2

– Metasoma tergum I not enlarged, longer than wide in dorsal view, dilated gradually in lateral view 19

2. Malar space longer than wide; clypeus narrowly separated from the eyes, or when in contact just by tapping on the margin of the eyes; color light brown to dark yellow; generally, more robust species, with 30 mm long or more P. (Onerarius) – P. carnifex (from southern United States to Argentina)

– Malar space as long as wide or weakly transverse; clypeus always in contact with the eyes, usually the part in contact with the eye is less than or equal to the diameter of the antenal socket size 3

3. Mesepisternum with epcinemial carina incomplete; last visible metasoma sternum without a tubercle P. (Palisotius) – 4

– Mesepisternum without an epcinemial carina, some species have a small groove but no carina; last visible metasoma sternum with a central tubercle P. (Fuscopolistes) – 6

4. Pronotum humeri projected laterally, in dorsal view; epicnemial groove absent; color dark brown with reddish aspect, with few yellow markings; scutum black with large brown spots; propodeum dark brown with two broad yellow stripes laterally P. paraguayensis (in central-south Brazil, Argentina and Paraguay)

– Pronotum humeri not projected laterally, pronotum rounded on the sides, in dorsal view; with a weak epicnemial groove; pigmentation light brown or yellowish without reddish aspect; propodeum with uniform color 5

5. General color yellow or dark brown; when yellow, with some dark-brown spots on the base of tergum and legs; when brown, almost completely dark brown, without spots of other color; scutum completely dark brown in both forms; terga I–II with evident bristles; dark-brown wings P. major (from the United States to central Brazil)

– General color light brown; without black spots and reduced yellow marks in pronotum; terga I–II without evident bristles; light-brown wings P. palmarum (southwestern United States and Mexico)

6. Dorsal groove evanescent, present only in initial dorsal portion; generally small, 15 mm long P. poeyi (Cuba, Haiti, and Dominican Republic)

– Dorsal groove developed, usually complete; usually more robust, larger than 20 mm long 7

7. Color of metasoma entirely brown or black, without evident yellow marks but when present are reduced to an apical yellow band in tergum I 8

– Color of metasoma entirely yellow or brown; when brown with large yellow marks and may have apical yellow band in the terga I–VI 13

8. Mesosoma black or extensively dark brown; metasoma completely black, sometimes terga I–II with dark-brown aspect, and may or may not have apical yellow bands 9

– Mesosoma brown; metasoma completely brown 11

9. Scutum dark brown, with two black stripes in the sides; terga I–II black with dark-brown aspect, terga III–VI black P. metricus (United States)

– Scutum completely black; terga I–VI black, usually tergum I with an apical yellow band 10

10. Tergum I with a longer apical yellow band; punctation a little deeper and stronger with distinct punctures on mesosoma and clypeus P. parametricus (United States)

– Tergum I with a narrow apical yellow band; punctation very small and shallow, without distinct punctures on mesosoma and clypeus P. hirsuticornis (United States)

11. Propodeal striae strongly marked and extending to the metanotum border; clypeus punctation deep and spaced; usually more robust, about 25 mm long P. rubiginosus (United States)

– Propodeal striae strong only on the center and weak on the sides, not extending to the metanotum border; clypeus with a small and shallow punctation; usually smaller species, less than 23 mm longer 2

12. General color brown, with a few black marks when they are present; dorsal groove weak P. carolina (United States)

– General color brown, with large black marks on the tergum and legs; sometimes general color dark-brown, almost black; dorsal groove strongly marked P. fuscatus (in part) (southern Canada and the United States)

13. Metasoma yellow or brown with extensive, poorly defined yellow spots covering almost entirely 14

– Metasoma brown with well-defined apical yellow bands 16

14. Color of the head and mesosoma dark-brown with some black marks on the vertex and scutum; terga I–III brown at the base and almost entirely colored with irregular yellow spots, terga IV–VI yellow P. aurifer (southern Canada, United States and Mexico)

– Color of the head and mesosoma yellow without black marks; tergum I completely yellow or with brown spots, terga II–VI entirely yellow 15

15. Scutum with large light-brown marks; tergum I with brown base and apical region more yellow; wings hyaline to light brown P. apachus (United States and Mexico)

– Scutum completely yellow or yellow with one central brown mark; tergum I completely yellow; wings reddish black P. flavus (United States and Mexico)

16. Clypeus touching the eyes by a distance equal to the diameter of antennal socket 17

– Clypeus touching eyes by a distance shorter than the diameter of antennal socket 18

17. General color light brown with small black marks; scutum brown with a narrow central mark and two black side stripes; mesepisternum brown; vertex black only on the region of the ocelli; coxae brown P. bellicosus (United States)

– General color dark brown with large black marks; scutum completely black; mesepisternum black; vertex largely black; coxae black P. fuscatus (in part) (southern Canada and the United States)

18. General color dark brown, with larger yellow marks; usually a yellow mark on the region of the gena; scutellum and metanotum with yellow markings; propodeum with two yellow lateral stripes P. dorsalis (southern United States, Mexico to Costa Rica)

– General color light brown, appearance paler; yellow marks reduced; gena completely light brown; scutellum and metonotum brown; propodeum brown without two yellow lateral stripes P. rossi (southern United States and Mexico)

19. Mesepisternum with an epicnemial carina, sometimes incomplete and sometimes weak, but always present P. (Epicnemius) – 20

– Mesepisternum without an epicnemial carina P. (Aphanilopterus) – 43

20. Mesepisternum with a dorsal groove, sometimes incomplete and sometimes weak, but always present 21

– Mesepisternum without a dorsal groove 26

21. Clypeus separated from the eyes; general color brown, mesepisternum largely black P. thoracicus (central Brazil, Argentina and Paraguay)

– Clypeus always in contact with the eye 22

22. Clypeus in contact with the eyes for a distance shorter than the diameter of the antennal socket; humeri weakly projected on the sides; pronotum more rounded 23

– Clypeus in contact with the eyes for a distance equal or larger than the diameter of antennal socket; humeri strongly projected on the sides; pronotum quadrate, with a central projection 24

23. Scutum black; mesosoma with large yellow marks; terga I–VI with apical yellow bands; reduced pubescence, when present, whitish in appearance; wings hyaline to light brown P. billardieri (from northern Colombia to southern Brazil and Argentina)

– Scutum reddish brown with ferruginous aspect; mesosoma with reduced yellow marks; tergum I with apical yellow bands, terga II–VI color uniform black, without apical yellow bands; pubescence more evident and golden; wings dark brown P. subsericeus (from Venezuela to central Brazil)

24. General color light brown, mesosoma with large yellow marks; metasoma completely light brown without dark spots P. claripennis (Brazilian Amazon and Peru)

– General color yellow, mesosoma with brown marks; metasoma yellow with large black spots 25

25. Top region of the gena more enlarged, in dorsal view; tergum I slender and with black spots; tergum II yellow with black mark only at apex P. moraballi (Guyana)

– Top region of the gena narrower, in dorsal view; tergum I more robust and yellow and with reduced black spots, tergum II completely yellow, terga III–VI almost entirely black P. testaceicolor (from Costa Rica to the Brazilian Amazon)

26. Gena largely dilated on central region, genal width always wider than eye, in lateral view 27

– Genal width equal to or slightly wider than eye on central region in lateral view 29

27. Anterior margin of pronotum sinuous, with a strong central projection P. atrox (Brazil: Pará)

– Anterior margin of pronotum straighter, without a central projection 28

28. Metasoma dark brown; golden pubescence more evident P. rufiventris Colombia, Ecuador, Guyana, and the Brazilian Amazon)

– Metasoma light brown; golden pubescence not evident P. occiptalis (from Panama to central Brazil)

29. Clypeus in contact with the eyes for a distance shorter than the diameter of the antennal socket 30

– Clypeus in contact with the eyes for a distance equal to or larger than the diameter of antennal socket 34

30. General color black, sometimes with small brown marks; metasoma completely black 31

– Head and mesosoma almost entirely black; metasoma completely brown 33

31. Color totally black, without brown spots; wings with blackish to dark brown; whitish pubescence around all over the body P. niger (Colombia and Brazil)

– General color black, with small brown marks; wings brown but never blackish; golden pubescence around the body 32

32. Anterior margin of pronotum rounded; gena slightly dilated on central region, genal width wider than eye, in lateral view; generally more robust, about 20 mm long P. deceptor (from Panama to central Brazil)

– Anterior margin of pronotum straighter, rounded only on humeral region; genal width equal to eye width on central region in lateral view; smaller, usually not exceeding 17 mm long P. obscurus (Brazil, Argentina, and Paraguay)

33. Anterior margin of pronotum sinuous, with a weak central projection; humeri strongly projected; wings hyaline with dark-brown to black venation; more robust species, usually more than 20 mm long P. bicolor (from Costa Rica to central-south Brazil)

– Anterior margin of pronotum straight, humeri weakly projected; wings brown with light-brown venation; small species usually not exceeding 15 mm long P. bequaertianus (Argentina: Misiones; Paraguay)

34. Anterior margin of pronotum sinuous, with a strongly central projection 35

– Anterior margin of pronotum straighter or rounded, without a central projection 36

35. General color black, usually with small brown marks; anterior margin of pronotum with a weak central projection; larger species, usually more than 20 mm long P. melanossoma (from Guiana to southern Brazil and Argentina)

– General color black with pronotum, scutum, and tegulae dark brown; anterior margin of pronotum with a very strong central projection; smaller species, usually not exceeding 17 mm long P. angulinus (Guyana and the Brazilian Amazon)

36. Species of small size, no more than 12 mm long 37

– Species intermediate in size, generally larger than 15 mm long but not exceeding 20 mm 38

37. General color black, with large brown marks on pronotum, mesepisternum, propodeum, and legs; narrow yellow bands on mesosoma; terga I–II with an apical yellow band; golden pubescence on the whole body P. geminatus (from Guyana to central Brazil)

– General color black without large brown marks; larger yellow bands on mesosoma; terga I–VI with an apical yellow band; whitish pubescence on the whole body P. davillae (Brazilian Amazon)

38. General color of metasoma brown, some specimens black with yellow marks P. pacificus (from southern United States to southern Brazil and Argentina)

– General color of metasoma black 39

39. Terga black with apical yellow bands 40

– Terga completely black without apical yellow bands 42

40. Terga I–III with apical yellow bands, terga IV–VI black P. boharti (Mexico)

– Terga I–VI with apical yellow bands 41

41. Mesosoma with small yellow marks; propodeum completely black; punctation deep and bigger on clypeus and mesepisternum P. cinerascens (from Mexico to southern Brazil and Argentina)

– Mesosoma black with yellow marks on the pronotum, scutum with two yellow stripes on the sides, scutellum and metanotum almost entirely yellow; propodeum with two yellow stripes on the side; punctation evanescent and shallow on clypeus and mesepisternum P. torresae (Guyana, Suriname, and the Brazilian Amazon)

42. Mesosoma almost black with small yellow marks; propodeum with two narrow yellow stripes on the sides; tergum I completely black ;P. actaeon (Brazil, Argentina, and Paraguay)

– Mesosoma partially black with large yellow marks, scutum with two yellow stripes on the sides, scutellum and metanotum almost entirely yellow; propodeum with two larger yellow stripes on the sides; tergum I black with circular spots on the sides P. candidoi (Bolivia)

43. Mesepisternum with punctation small and shallow, without distinct, deep, and large punctures; propodeum with weak or moderately strong striae, usually concentrated on the center, not touching the lateral margin of propodeum, if touching the side, they are very weak; usually smaller species 44

– Mesepisternum with punctation bigger and deeper, with the presence of distinct, deep, and large punctures; propodeum with strong striae, developed to the lateral margin of propodeum; usually larger species 75

44. Pronotal carina strongly acuminate, sharp; general color black without pale marks; when these are present, extremely small; wings completely or partly black 45

– Pronotal carina weak, if higher then rounded and never acuminate; varied color, never completely black, with large yellow and ferruginous marks; wings hyaline to brown, but never black 47

45. General color black with metallic appearance; wings completely black; apex of clypeus and mandibles reddish; punctation very small and shallow P. goeldii (Bahamas, Dominican Republic, and from Costa Rica to central Brazil)

– General color black without metallic appearance; wings dark brown; clypeus and mandible totally black 46

46. Occipital carina developed at the end of the gena; general color black with dark-brown markings defined on pronotum, scutellum, tegulae, and legs; wings dark brown over their entire surface P. penai (Peru and Bolivia)

– Occipital carina developed at the middle of the eyes; color completely black, no brown marks; wings dark brown at the base and becoming hyaline halfway to apex P. apicalis (Mexico, Central America to Guyana and Ecuador)

47. Propodeum with weak striae only on middle of central concavity, not touching the lateral margin of propodeum; species usually with apical yellow bands on some terga 48

– Propodeum with moderately strong striae on the middle of central concavity, touching the sides weakly; species usually without apical yellow bands on terga, but with circular spots on tergum I and sometimes on tergum II 62

48. Pronotum rounded but humeri slightly projected on the sides 49

– Pronotum rounded to the fullest extent with the humeri not projected on the sides 56

49. Eyes with small bristles on their entire surface 50

– Eyes bare 52

50. Pronotum and scutum with black color, with large yellow marks; tergum black with brown and yellow apical bands; size large, ∼20 mm long or longer P. cubensis (Bahamas and Cuba)

– Small species, not exceeding 18 mm long; color different from above 51

51. Golden pubescence on the whole body; scutum black with large brown marks and two yellow stripes on the sides; terga I–VI with narrow yellow apical bands P. incertus (Cuba, Haiti, and Dominican Republic)

– Whitish pubescence on the whole body; scutum light brown with two yellow stripes on the sides; terga I–VI with larger yellow apical bands P. minor (Mexico, Cuba, Haiti, Dominican Republic, and Puerto Rico)

52. Pronotal fovea reduced and shallow; very small species, not exceeding 13 mm long; scutum light brown; propodeum black with two yellow stripes on the sides P. crinitus (Jamaica, Dominican Republic, Puerto Rico, and Peru)

– Pronotal fovea developed; species medium sized, about 15–20 mm long; scutum dark brown, sometimes with yellow markings; propodeum brown with two yellow stripes on the sides 53

53. Mesepisternum black with yellow markings; coxae and femur black, apical region of femur yellow 54

– Mesepisternum brown with yellow markings; coxae and femora brown, apical region of femur yellow 55

54. Pronotal carina higher; scutellum brown with a wide yellow mark; propodeum striae a little stronger on the center P. pseudoculatus (Mexico: Chihuahua)

– Pronotal carina lower; scutellum completely yellow; propodeum striae less developed and weakly marked on the center .P. instabilis (from Mexico to Costa Rica)

55. Scutum narrow and partially black with two yellow stripes on the sides; about 20 mm long…… P. bequaertellus (El Salvador)

– Scutum wider and completely brown without yellow stripes on the sides; about 18 mm long P. stabilinus (from Mexico to Honduras)

56. Genal width at center less than eye width, in lateral view 57

– Genal width at center wider than eye width, in lateral view 58

57. Scutum, propodeum and tergum completely black; terga I–IV with yellow apical bands and terga V–VI with brown apical bands P. franciscanus (Guatemala)

– Scutum and propodeum brown, scutum with two yellow stripes on the sides; terga partially brown, terga I–VI with yellow apical bands P. lineonotus (southwestern United States, Mexico, and Dominican Republic)

58. Scutum black, with small brown lateral marks; mesosoma with small yellow marks; terga I–IV brown with yellow apical bands; wing venation light-brown ,P. bahamensis (southern United States and Bahamas)

– Scutum brown; mesosoma with larger yellow marks; wing venation dark brown 59

59. Terga dark brown, without yellow apical bands; mesepisternum black with a yellow mark P. ridleyi (Brazil: Fernando de Noronha)

– Terga brown, with yellow apical bands; mesepisternum black or brown 60

60. General color brown with extensive black marks; mesepisternum black with a yellow mark; propodeum black with two yellow stripes on the sides; legs largely black P. oculatus (from Mexico to Costa Rica)

– General color brown with reduced black marks; mesepisternum brown with yellow marks; propodeum brown with two yellow stripes on the sides; legs largely brown 61

61. Terga brown, I–VI with larger yellow apical bands P. exclamans (United States and Mexico)

– Terga brown, I–III with smaller yellow apical bands P. arizonensis (southwestern United States and Mexico)

62. Pronotal carina a little higher and usually developed to the end of pronotum, exceeding the humeral region 63

– Pronotal carina slightly lower and developed up to the humeri, but not extending into the humeri region of pronotum 69

63. General color pale yellow P. eburneus (Paraguay: Guaira)

– General color black or brown, with large yellow marks 64

64. Scutum with general color black 65

– Scutum with general color brown 66

65. Scutum completely black; pronotum and propodeum yellow; terga I–II completely or mostly yellow; terga III–VI with reddish-brown color P. maranonensis (Ecuador and Peru)

– Scutum mostly black, with reduced brown stripes on the sides; pronotum and propodeum brown with yellow markings; terga I–VI brown, with yellow marks P. xanthogaster (Peru, Bolivia, and northern Argentina)

66. General color light brown; terga I–II with apical yellow bands and without spots on the side P. veracrucis (Mexico)

– General color dark brown; terga I–II with yellow spots on the side 67

67. Mesepisternum completely black; scutelum and metanotum dark-brown, without yellow marks; propodeum completely dark brown P. myersi (Bahamas and from Costa Rica to Colombia)

– Mesepisternum black with yellow marks; scutelum and metanotum dark-brown, with yellow marks; propodeum completely brown with two yellow stripes on the sides 68

68. Humeri weakly projected on the sides P. ninabamba (Peru: Ayacucho)

– Humeri not projected on the sides; pronotum rounded P. versicolor (Dominican Republic and from Costa Rica to southern Brazil and Argentina)

69. Scutum with general color black 70

– Scutum with general color brown 73

70. Extended yellow marks on the body; pronotum, scutellum, and metanotum with yellow markings; propodeum with two yellow stripes on the sides 71

– General coloration brown or black, with rare yellow marks; pronotum, scutellum, and metanotum black; propodeum totally black 72

71. Terga I–II and rarely III with yellow circular spots on the sides P. weyrauchorum (Ecuador, Peru, and Chile)

– Terga I–IV with yellow circular spots on the sides well defined P. peruvianus (Peru)

72. Integument with a shiny appearance and punctation generally stronger, with some clusters of punctures on mesepisternum; general color black with small brown marks on the face, pronotum, tegulae, and legs; terga I–VI black, II with two yellow circular spots on the sides .P. binotatus (Brazil: Rio de Janeiro)

– Integument dull, without a shiny appearance, and punctation generally thinner and shallower on mesepisternum; general color black with large brown marks on the face, pronotum, tegulae, and legs; terga I–VI brown, I with two yellow circular spots on the sides P. biguttatus (Brazil)

73. General color dark brown, almost black, with small brown marks on pronotum, scutum, and scutellum; face dark brown; propodeum completely black; tergum dark brown, without the presence of yellow spots P. consobrinus (southern Brazil, Paraguay, Argentina, and Uruguay)

– General color light brown, with larger yellow marks; face light brown; propodeum black or brown with two yellow stripes on the sides; terga light brown, with yellow spots 74

74. Scutum distinctly longer than wide; propodeum black with two yellow stripes on the sides; tergum I with two well-defined circular spots on the sides P. adelphus (Colombia, Ecuador, and Peru)

– Scutum as long as wide; propodeum brown with two yellow stripes on the sides; terga I–II with two well-defined circular spots on the sides P. simillimus (Colombia, Peru, Bolivia, central-south Brazil, Paraguay, and Argentina)

75. Pronotal carina strongly elevated and acuminate, sharp; anterior margin of pronotum more straight, and rounding only on the humeral region; general color black, normally without marks on the body, but if so size extremely small 76

– Pronotal carina weakly elevated, and if higher then rounded and never acuminate; anterior margin of pronotum more rounded; general color dark brown, never completely black 79

76. Humeri strongly projected; wings blackened; general color of mesosoma black, no brown areas 77

– Humeri not projected; wings dark brown; general color of mesosoma black, but pronotum and scutellum brown 78

77. Pronotal carina developed by the end of pronotum, going beyond the humeral region; clypeus apex and mandible reddish P. rufidens (Colombia and Venezuela)

– Pronotal carina developed to the humeral region, not reaching the end of pronotum; clypeus apex and mandible black P. aterrimus (from Costa Rica to northern Argentina)

78. Dorsal groove incomplete and weak; propodeum striae less developed and weakly marked on the sides P. penai (Peru and Bolivia)

– Dorsal groove complete and strong; propodeum striae more developed and more marked on the sides P. huacapistana (Peru: Junín)

79. General color light brown to pale yellow with some areas marked in black; terga completely pale yellow or, if brown, with large yellow spots 80

– General color dark brown to black; terga dark brown, only tergum I partially yellow 86

80. Scutum and propodeum black; terga black with large brown and yellow spots 81

– Scutum and propodeum brown, sometimes with yellow markings; terga brown, sometimes with large yellow spots 83

81. Pronotum and scutellum with large yellow marks; face and gena yellow; terga I–VI with basal part black, central part brown and with narrower, well-defined yellow apical bands P. buyssoni (Bolivia, Argentina, and Chile)

– Pronotum and scutellum with large brown marks; face and gena yellow or brown; terga I–II with basal part black, central part brown and with larger yellow apical bands, terga III–VI completely pale yellow 82

82. Face and gena with brown color; clypeus brown P. cavapytiformis (southeastern and southern Brazil)

– Face and gena with yellow color; clypeus yellow P comanchus (southern United States and Mexico)

83. General color reddish brown; tergum I with very large yellow apical band covering almost tergum I; humeri projected; intermediate in size, not exceeding 20 mm long P. dominicus (Bahamas, Cuba, and Brazil)

– General color light brown; tergum I totally brown, sometimes with a very narrow yellow apical band; humeri not projected; larger species, usually more than 20 mm long 84

84. Scutum brown, usually with yellow stripes on the sides; propodeal muscle orifice relatively short and wide; terga II–VI with large yellow spots on the entire length; large species, about 30 mm long P. cavapyta (Brazil to Argentina and Paraguay)

– Scutum completely brown; propodeal muscle orifice relatively long and slender; terga I–VI light brown and without large yellow spots; species about 25 mm long 85

85. Face and gena brown; wings dark brown, with reddish appearance, venation dark brown, almost black; terga brown, I with a well-defined yellow apical band P. mexicanus (Mexico)

– Face and gena yellow; wings light brown, with hyaline appearance, venation light brown; terga brown without well-defined yellow apical bands P. kaibabensis (southwestern United States and Mexico)

86. Scutum, scutellum, and metanotum completely black or with small brown marks; metasoma black or brown 87

– Scutum, scutellum, and metanotum brown; metasoma usually brown 91

87. General color black, with brown or red spots on the face and legs; wings blackened; tergum completely black 88

– General color brown, with yellow marks, sometimes on the face, legs, or terga; wings brown; terga brown 89

88. Head with reddish appearance, color different from the rest of the body P. erythrocephalus (from Nicaragua to central Brazil)

– Head with black appearance, color similar to the rest of the body P. satan (southwestern Brazil)

89. Pronotum black; terga II–VI with extensive light-brown spots P. brevifissus (from Panama to southern Brazil and Argentina)

– Pronotum brown; terga II–VI brown or reddish spots 90

90. Scutum black and usually with small brown marks; tergum I with a large yellow apical band, but sometimes without it; terga II–VI dark brown P. lanio (from Panama to southern Brazil and Argentina)

– Scutum completely black; terga I–VI brown with reddish appearance on apical region, but without yellow apical bands P. melanotus (Colombia and southeastern Brazil)

91. Propodeal muscle orifice short and wide, rounded at the top; general color brown with reddish appearance; femora with a yellow apical band; propodeum may or may not have two yellow stripes on the sides P. ferreri (Brazil, Bolivia, and Argentina)

– Propodeal muscle orifice long and slender, acuminate at the top; general color dark brown with reddish appearance; propodeum without two yellow stripes on the sides 92

92. Tergum I with yellow apical band; terga II–VI completely black P. annularis (United States and Mexico)

– Terga usually black or brown; tergum I uniform in color, without the presence of a yellow apical band 93

93. Propodeum completely black P. notatipes (southeastern and southern Brazil)

– Propodeum completely brown 94

94. Head yellow or light brown, usually a little lighter than the rest of the body; black marks reduced or absent P. infuscatus (from Honduras to the Brazilian Amazon)

– Head dark brown, usually same color as the rest of the body; black marks more evident, especially in mesosoma P. canadensis (southern United States to southern Brazil and Argentina)