Polistes

Key to the Brazilian Polistes species The dichotomous key is based on females and adapted from Richards (1978) and Somavilla et al. (2021b). Geographical distribution is summarized. 1. Tergum I more enlarged, wider than long or as wide as long in dorsal view, dilated abruptly in lateral view.............. 2 - Tergum I not enlarged, longer than wide in dorsal view, dilated gradually in lateral view............................. 4 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 (From southern United States to South Brazil and Argentina)...................................... P. (Onerarius) carnifex (Fabricius, 1775) - 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 antennal socket...................subgenus Palisotius ............... 3 3. Pronotal 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 (In central-south Brazil, Argentina and Paraguay).............................................. P. (P.) paraguayensis Bertoni, 1921 - Pronotal humeri not projected laterally, pronotum rounded on the sides, in dorsal view; with a weak epicnemial groove; general color yellowish or light brown; scutum completely dark brown, propodeum yellowish (From the United States to central Brazil)............................................................... P. (P.) major Palisot de Beauvois, 1818 4. Mesepisternum with an epicnemial carina, sometimes incomplete and sometimes weak, but always present............................................................................. subgenus Epicnemius .................... 5 - Mesepisternum without an epicnemial carina.......................... subgenus Aphanilopterus ................26 5. Mesepisternum with a dorsal groove, sometimes incomplete and sometimes weak, but always present.................. 6 - Mesepisternum without a dorsal groove................................................................... 11 6. Clypeus separated from the eyes; general color brown, mesepisternum largely black (Central Brazil, Argentina and Paraguay)............................................................................. P. (E.) thoracicus Fox, 1898 - Clypeus always in contact with the eye; general color varied................................................... 7 7. 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........................................................................... 8 - 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..................................................... 9 8. 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 (From northern Colombia to southern Brazil and Argentina)................................................................................. P. (E.) billardieri (Fabricius, 1804) - Scutum reddish brown with ferruginous aspect; mesosoma with reduced yellow marks; tergum I with apical yellow bands, terga II–VI color uniformly black, without apical yellow bands; pubescence more evident and golden; wings dark brown (From Venezuela to central Brazil)............................................... P. (E.) subsericeus de Saussure, 1854 9. Mesepisternum with an incomplete dorsal groove, interrupted from the middle to the upper part; general color yellow; scutum yellowish with three distinct longitudinal black stripes (Brazilian Amazon)... P. (E.) orlandoi Somavilla & Carpenter, 2022 - Mesepisternum with a complete dorsal groove; general color light brown to yellow; scutum without three distinct longitudinal stripes black........................................................................................ 10 10. General color light brown, mesosoma with large yellow marks; metasoma completely light brown without dark spots (Brazilian Amazon and Peru)....................................................... P. (E.) claripennis de Saussure, 1854 - General color yellow, mesosoma with brown marks; tergum I yellow and with reduced black spots, tergum II completely yellow, terga III–VI almost entirely black (From Costa Rica to the Brazilian Amazon).. P. (E.) testaceicolor Bequaert, 1937 11. Gena largely dilated on central region, genal width always wider than eye, in lateral view.......................... 12 - Genal width equal to or slightly wider than eye on central region in lateral view.................................. 14 12. Anterior margin of pronotum sinuous, with a strong central projection (Pará, Brazil).......... P. (E.) atrox Richards, 1978 - Anterior margin of pronotum straight, without a marked central projection...................................... 13 13. Metasoma dark brown; golden pubescence more evident (Colombia, Ecuador, Guiana, and the Brazilian Amazon).................................................................................... P. (E.) rufiventris Ducke, 1904 - Metasoma light brown; golden pubescence not evident (From Panama to central Brazil)..... P. (E.) occipitalis Ducke, 1904 14. Clypeus in contact with the eyes for a distance shorter than the diameter of the antennal socket...................... 15 - Clypeus in contact with the eyes for a distance equal to or larger than the diameter of antennal socket................. 19 15. Propodeum straighter, without a central concavity on middle................................................. 16 - Propodeum with a central concavity on middle............................................................ 18 16. Anterior margin of pronotum sinuous, with a weak central projection; humeri projected; wings hyaline with dark brown to black venation; more robust species, usually more than 20 mm long (From Costa Rica to central-south Brazil)............................................................................................ P. (E.) bicolor Lepeletier, 1836 - Anterior margin of pronotum straighter, rounded only on humeral region; wings yellowish or brownish; small species usually not exceeding 18 mm long............................................................................ 17 17. Body black to brown, metasoma completely brown; wing brownish (Brazil, Argentina, and Paraguay).......................................................................................... P. (E.) bequaertianus Willink, 1954 - Body dark brown to black, metasoma with the apex terga yellow; wings yellow to weakly brown (Brazil, Argentina, and Paraguay)................................................................ P. (E.) obscurus de Saussure, 1863 18. General color black, with small brown marks; wings light brown but never blackish; golden pubescence around the body; generally, more robust, about 20 mm long (From Panama to central Brazil)................ P. (E.) deceptor Schulz, 1905 - Color totally black, without brown spots; wings with blackish to dark brown; whitish pubescence around all over the body; smaller, usually not exceeding 15 mm long (Colombia and Brazil)......................... P. (E.) niger Brèthes, 1903 19. Anterior margin of pronotum sinuous, with a strongly central projection........................................ 19 - Anterior margin of pronotum straighter or rounded, without a central projection.................................. 20 20. 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 (From Guiana to southern Brazil and Argentina)................................................................................................... P. (E.) melanosoma de Saussure, 1853 - 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 (Guiana and the Brazilian Amazon).............................................................................................. P. (E.) angulinus Richards, 1951 21. Species of small size, no more than 12 mm long........................................................... 22 - Species intermediate in size, generally larger than 15 mm long but not exceeding 20 mm ........................... 23 22. 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 (From Guiana to central Brazil)................................................................................. P. (E.) geminatus Fox, 1898 - 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 (Brazilian Amazon)............................ P. (E.) davillae Richards, 1978 23. General color of metasoma brown (From southern United States to southern Brazil and Argentina)............................................................................................... P. (E.) pacificus Fabricius, 1804 - General color of metasoma black....................................................................... 24 24. Terga black with apical yellow bands.................................................................... 25 - Terga completely black without apical yellow bands; propodeum with two narrow yellow stripes on the sides (Brazil, Argentina, a