VESPIDAE

Selis, Marco, 2023, Illustrated key to the genera and a checklist of Italian Vespidae (Hymenoptera), Fragmenta entomologica 55 (1), pp. 63-88 : 65-69

KEY TO THE GENERA AND SUBGENERA OF ITALIAN VESPIDAE

1. Apical antennomeres forming a club ( Fig. 1 a, e ). Fore wing with two submarginal cells, first discoidal cell touching medial cell ( Fig. 1 c )...................2, Masarinae

- Apical antennomeres normal, not forming a club ( Fig. 1 b ). Fore wings with three submarginal cells, first discoidal cell not touching medial cell ( Fig. 1 d )...............3

2. Sides of tergites pointed, forming more or less triangular projections ( Fig. 1 f ); metasoma flattened on ventral side. Scape short and spherical ( Fig. 1 a ). Occipital carina complete.......................... Celonites Latreille, 1802

- Sides of tergites regularly rounded ( Fig. 1 g ); metasoma cylindrical. Scape more or less cylindrical, longer than following segment ( Fig. 1 e ). Occipital carina incomplete............................. Jugurtia de Saussure, 1854

3. Tarsal claws bifid ( Fig. 1 h ). Gena strongly tapering below, posterobasal corner of mandible nearly touching ocular margin ( Fig. 1 j ).............................4, Eumeninae

- Tarsal claws simple ( Fig. 1 i ). Gena not tapering below, posterobasal corner of mandible widely separated from ocular margin ( Fig. 1 k ).............................................43

4. Second recurrent vein received by third submarginal cell ( Fig. 2 a ). Very long mouthparts, reaching hind coxae ( Fig.2c ).Clypeuslaterallyexpandedbysubtriangularexpansions.......................................................................5

- Both recurrent vein received by second submarginal cell ( Fig. 2 b ). Mouthparts short and barely exceeding mandibles, if long then not reaching hind coxae ( Fig. 2 d ). Clypeus not expanded......................................................6

5. Metasoma sessile ( Fig. 2 e )............................................ ............................................ Psiliglossa Saunders, 1852

- Metasoma petiolate ( Fig. 2 f )......................................... ......................................... Raphiglossa Saunders, 1850

6. Mid tibia with two apical spurs ( Fig. 2 g )....................... .............................................. Discoelius Latreille, 1809

- Midtibiawithoneapicalspur( Fig.2h )...........................7

7. 7. Metasoma petiolate, T1 several times longer than wide and narrower than half of T2 ( Fig. 3 a )...................8

- Metasoma sessile, T1 at most slightly narrower than T2 ( Fig. 3 b-d).................................................................11

8. T2 with an apical black or translucent lamella, sharply separated from the rest of the tergite by a step ( Fig. 3 e ) ............................................... Eumenes Latreille, 1802

- T2 without an apical lamella, at most with a narrow decolorate margin not separated by a step ( Fig. 3 f ).........9

9. Apical margin of clypeus convex ( Fig. 3 g ). In male, fore tarsomeres shortened and with lateral spine ( Fig. 3 i ), mid basitarsus with usually convex lateral margin .... ................................... Katamenes Meade-Waldo, 1910

- Apical margin of clypeus truncated or concave ( Fig. 3 h ). In male, tarsi not modified.........................................10

10. T1 very long and narrow, parallel-sided in the posterior two thirds and dorsally flattened ( Fig. 4 a )..................... ................................. Ischnogasteroides Magretti, 1884

- T1 pyriform, widened in the apical half and dorsally convex ( Fig. 4 b )...................... Delta de Saussure, 1855

11. Second submarginal cell petiolate ( Fig. 4 c ). Tegulae large, covering parategulae ( Fig. 4 d )........................... ................................................ Alastor Lepeletier, 1841

- Second submarginal cell not petiolate. Tegulae different, parategulae well visible ( Fig. 4 e-f)..............................12

12. Tegulae elliptical, posteriorly rounded ( Fig. 4 e ). Antenna of male apically spiraled ( Fig. 4 g )..........................13

- Tegulae with a pointed posterior lobe, more or less developed but always evident ( Fig. 4 f ). Antenna of male apically simple or hooked ( Fig. 8 g-h).........................21

13. Labialpalpi3-segmented,elongatedandwithlongfringes of setae at least in the female( Fig.5 a-c).Elongate mouth - parts...........................................................................14

- Labial palpi with 4-segmented, short and with very sparse short setae in both sexes ( Fig. 5 d ). Short mouthpa rts...............................................................................16

14. Maxillary palpi 5-segmented. Third segment of labial palpi narrow and parallel-sided, with long fringes of setae in both sexes ( Fig. 5 a ). Apical margin of clypeus widely truncate ( Fig. 5 e )........ Pterocheilus Klug, 1805

- Maxillary palpi 6-segmented. Labial palpi different ........................................................................................15

15. 15. Third segment of labial palpi narrower than preceding one, ending in a long narrow point ( Fig. 5 b ). Male lacking apical fringes of setae on sternites .................... ...................................... Hemipterochilus Ferton, 1909

- Third segment of labial palpi wider than preceding one, flattened and with curved margins, apically rounded ( Fig. 5 c ). Male with apical fringes of dense setae on sternites............... Onychopterocheilus Blüthgen, 1955

16. Head and mesosoma with short pubescence ( Fig. 5 f ). Vertex with a fine longitudinal carina in the middle, in the female without cephalic foveae ( Fig. 6 a ). S4-7 of male with short and dense, woolly vestiture ( Fig. 6 e ) ................................... Tropidodynerus Blüthgen, 1939

- Head and mesosoma with long setae ( Fig. 6 f ). Vertex without longitudinal carina, in female with cephalic foveae ( Fig. 6 b-d). Male sternites without wool-like vestiture..........................................................................17

17. In female, clypeus deeply incised apically and mandible with a deep incision between third and fourth teeth ( Fig. 6 g ). Cephalic foveae punctiform, close to each other in the middle of vertex ( Fig. 6 b ). Male without modifications on legs and gena ..................................... ....................................... Gymnomerus Blüthgen, 1938

- In female, clypeus more or less apically truncate and mandible normal ( Fig. 6 h , 7 a ). Cephalic foveae widely separated and placed behind posterior ocelli ( Fig. 6 c-d). Male usually with modified legs........................18

18. Large-sized species (13-17mm). Parapsidal furrows deep in the posterior half of mesoscutum ( Fig. 7 b ). Cephalic foveae about as large as an ocellus and densely pubescent ( Fig. 6 c ). Mid femur of male apically expanded ( Fig. 7 d ) ..... Paragymnomerus Blüthgen, 1938

- Smaller species (8-13mm). Mesoscutum without parapsidal furrows ( Fig. 7 c ). Cephalic foveae much smaller than an ocellus and bare ( Fig. 6 d ). Mid leg of male differently modified ( Fig. 7 e, g ) ....................................................................19, Odynerus Latreille, 1802

19. Mid femur of male with two deep incisions, forming a median tooth ( Fig. 7 e ). In female, metanotum black ( Fig. 7 f ) ......................... O. ( Odynerus ) Latreille, 1802

- Midfemurofmalenormal,notincised.........................20

20. Mid coxa of male with a thorn at posteromedial corner ( Fig. 7 g ). Gena of male with a long thorn behind mandible articulation in some species ( Fig. 8 a ). Metanotum of female with yellow or white wide band ( Fig. 8 b ) .............................. O. (Spinicoxa) Blüthgen, 1938

- Mid coxa and gena of male without thorns. Metanotum of female black ( Fig. 7 f )................................................ ............................. O. (Monoplomerus) Blüthgen, 1941

21. Scutellum, metanotum and propodeum forming an even curve in lateral view. Propodeum with a median basal fovea, posteriorly continuing in a median longitudinal carina. Corners of propodeum prolonged in two lamellar triangular teeth ( Fig. 8 c ). T1 bell-shaped, longer than wide and narrower than T2 ( Fig. 8 d ) ......... ..................................... Pareumenes de Saussure, 1855

- Scutellum, metanotum and propodeum not forming an even curve. Propodeum without basal fovea, corners different. T1 different, at most as long as wide ( Fig. 3 b-d)............................................................................22

22. T1 with a basal transverse carina ( Fig. 8 e )................23

- T1 without carina........................................................27

23. T1 with a median longitudinal furrow behind carina ( Fig. 8 f ). Apical flagellomeres of male simple ( Fig. 8 g ) .................................... Symmorphus Wesmael, 1836

- T1 without longitudinal furrow. Apical flagellomeres of male hooked ( Fig. 8 h )..........................................24

24. Pronotum lacking pretegular carina ( Fig. 9 a ).....................25, Eustenancistrocerus Blüthgen, 1938

- Pronotum with pretegular carina ( Fig. 9 b )...................26

25. Tegulae not punctured but with two translucent spots ( Fig. 9 c ). S2 truncated basally, forming a step. Clypeus of male apically truncate........................................ .................. E. (Parastenancistrocerus) Blüthgen, 1938

- Tegulae with many deep punctures ( Fig. 9 d ). S2 evenly convex. Clypeus of male deeply incised apically ..................... E. ( Eustenancistrocerus ) Blüthgen, 1938

26. Head and mesosoma with long and dense setae ( Fig. 9 g ). Epicnemial carina absent. Tegulae narrow, longer than wide ( Fig. 9 e ). T1 evenly punctured behind transverse carina ( Fig. 9 h ). Female with cephalic foveae ..... ...................................... Ancistrocerus Wesmael, 1836

- Head and mesosoma with short and sparse pubescence ( Fig. 9 i ). Epicnemial carina present. Tegulae wider, about as long as wide ( Fig. 9 f ). T1 with a smooth unpunctured area behind transverse carina ( Fig. 9 j ). Female without cephalic foveae .................................. .................... Tachyancistrocerus Giordani Soika, 1952

27. T1 with an apical translucent lamella ( Fig. 3 b )...........28

- T1 without apical lamella ( Fig. 3 c-d)........................31

28. Pronotum with pronotal carina present only on humeri, dorsal face smoothly passing into anterior face ( Fig. 10 a ). Epicnemial carina barely visible, confused with sculpture of mesepisternum. Metasoma with long bristles pointing behind. In male, mid femur flattened below and hind tibia apically expanded ( Fig. 10 c ) .......... ..................................... Chlorodynerus Blüthgen, 1951

- Pronotum with complete pronotal carina, dorsal face sharply separated from anterior face ( Fig. 10 b ). Epicnemial carina sharp and well visible. Metasoma with very short and barely visible bristles. Male with unmodified legs.............................................................29

29. Metanotum evenly rounded. Dorsal carinae of propodeum forming long and sharp teeth, their distance narrower than the width of metanotum ( Fig. 10 d ).............. ................................... Syneuodynerus Blüthgen, 1951

- Metanotum sharply angled, with a fine teethed carina separating a short dorsal face and a longer posterior face. Dorsal carinae of propodeum absent or, if present, forming shorter teeth as far apart as the width of metanotum ( Fig. 10 e-f)......................................................................................30, Euodynerus Dalla Torre, 1904

30. Dorsal carinae of propodeum forming sharp teeth reaching half height of metanotum, separated from it by a narrow incision ( Fig. 10 e ). If carinae less developed, then upper side of mesosoma with brush-like vestiture. Vertex of female with subtriangular hairy depression, wider than ocellar triangle ( Fig. 10 g ). In male, mid and hind apical tarsomeres widened and black ( Fig. 10 h ).......................... E. (Pareuodynerus) Blüthgen, 1938

- Dorsal carinae of propodeum not exceeding base of metanotum and not forming teeth ( Fig. 10 f ). Vertex of female with rounded bare depression, narrower than ocellar triangle ( Fig. 10 i ). Tarsi of male not modified ( Fig. 10 j )............... E. ( Euodynerus ) Dalla Torre, 1904

31. T2 with an apical lamella ( Fig. 11 a ). Second submarginal cell basally right-angled to obtuse ( Fig. 11 c )....32

- T2 without lamella ( Fig. 11 b ). Second submarginal cell basally acute ( Fig. 11 d )......................................37

32. T1 much narrower than T2 ( Fig. 11 e ). Mesosoma short, mesoscutum about as long as wide ( Fig. 11 g ) .....................................33, Leptochilus de Saussure, 1853

- T1 barely narrower than T2 ( Fig. 11 f ). Mesosoma elongate, mesoscutum longer than wide ( Fig. 11 h ) ......................................35, Microdynerus Thomson, 1874

33. Tegulae widened posteriorly, larger than half scutellum ( Fig. 12 a )................ L. (Euleptochilus) Blüthgen, 1943

- Tegulae pointed posteriorly, smaller than half scutellum ( Fig. 12 b )..........................................................34

34. Apical lamella of T2 with fine sculpture and sharply separated from rest of tergites ( Fig. 11 a )....................... ..................................... L. (Lionotulus) Blüthgen, 1938

- Apical lamella of T2 with coarse punctures and connected with preapical margin of tergite by pigmented digitations ( Fig. 12 c )..................................................... .............................. L. (Neoleptochilus) Blüthgen, 1961

35. Mandibles of female wide and angled on outer margin ( Fig. 12 d ). F11 of male wide and flattened ( Fig. 12 f ) ................... M. (Pseudomicrodynerus) Blüthgen, 1938

- Mandibles of female normal, evenly curved ( Fig. 12 e )...................................................................................36

36. Apical margin of female clypeus bidentate ( Fig. 12 g ). S2 without a longitudinal furrow. F11 of male pointed .. ............................. M. ( Microdynerus ) Thomson, 1874

- Apical margin of female clypeus tridentate, median tooth prolonged in a sharp carina ( Fig.12 h ). S2 with a longitudinal furrow. F11 of male flattened and not pointed................... M. (Alastorynerus) Blüthgen, 1938

37. Pronotum lacking pretegular carina ( Fig. 13 a ). Tegulae as wide as long. Metanotum with two small teeth at extreme sides ( Fig. 13 c )............................................... ............................... Parodontodynerus Blüthgen, 1938

- Pronotum with pretegular carina ( Fig. 13 b ). Metanotum without teeth, if teeth present then larger and close to middle........................................................................38

38. Propodeum with a sharp and continuous dorsal carina ( Fig. 13 d ). Tegulae wide and expanded on outer margin ( Fig. 13 f ).......39, Pseudepipona de Saussure, 1856

- Propodeum without dorsal carinae, or with a widely interrupted one. Tegulae narrower...............................40

39. Sides of propodeum with a triangular expansion ( Fig. 13 e ). Male mandible with a deep incision between second and third teeth ( Fig. 13 g ) ....................................... ............................ P. ( Pseudepipona ) de Saussure, 1856

- Sides of propodeum without triangular expansion. Male mandible without incision.................................... ............................... P. (Deuterepipona) Blüthgen, 1951

40. Metanotum with two triangular teeth ( Fig. 13 h ) ........... ...................................... Antepipona de Saussure, 1855

- Metanotum without teeth...........................................41

41. Large sized species, red and black with yellow markings on metasoma. Posterior half of metanotum and whole scutellum flattened, smooth and shiny with extremely fine sculpture ( Fig. 14 a ). Male clypeus apically pointed ( Fig. 14 b ). Mid femur of male basally depressed ( Fig. 14 c )........... Rhynchium Spinola, 1806

- Smaller species, black with yellow or white markings, some species with red legs. Mesoscutum and scutellum convex, entirely covered by dense and deep punctures. Mid femur of male normal. Male clypeus apically emarginate................................................................42

42. Head and mesosoma with short setae ( Fig. 14 d ). Tegulae wide, campanulate and not exceeding parategulae, and axillary fossa large and rounded ( Fig. 14 e ). Anterior face of pronotum with a pair of pits in the middle and punctures in the lateral thirds ( Fig. 14 f )................ .................................. Stenodynerus de Saussure, 1863

- Head and mesosoma with long setae ( Fig. 14 g ). Tegulae narrow, exceeding parategulae, and axillary fossa small and punctiform ( Fig. 14 h ). Anterior face of pronotum entirely smooth ( Fig. 14 i ).................................. .......................................... Allodynerus Blüthgen, 1938

43. Clypeus apically pointed ( Fig. 15 a ). Vestiture very short on whole body. T1 weakly arched in lateral view, sub-petiolate and with diverging sides in dorsal view ( Fig. 15 b )................ Polistinae , Polistes Latreille, 1802

- Clypeus apically truncate or emarginate ( Fig. 15 c ). Vestiture long on whole body. T1 angled in lateral view, whit a long anterior vertical face and a shorter horizontal one, parallel-sided in dorsal view ( Fig. 15 d )...................................................................44, Vespinae

44. Distance between posterior ocelli and occipital margin much longer than two ocellar diameters ( Fig. 15 e ). Pronotal carina complete ( Fig. 16 a ). Male flagellum with strong tyloids ( Fig. 15 g )..... Vespa Linnaeus, 1758

- Distance between posterior ocelli and occipital margin as long as two ocellar diameters at most ( Fig. 15 f ). Pronotal carina absent or medially interrupted ( Fig. 16 b-c). Male flagellum without or with poorly defined tyloids ( Fig. 15 h )..........................................................45

45. Malar space long ( Fig. 16 d ). Pronotal carina present but widely interrupted in the middle ( Fig. 16 b )............. ..................................... Dolichovespula Rohwer, 1916

- Malar space short, almost linear ( Fig. 16 e ). Pronotal carina absent ( Fig. 16 c )........... Vespula Thomson, 1869

Figures

Fig. 1 – a, Celonites abbreviatus ♀, antenna. b, Polistes dominula ♀, antenna. c, Jugurtia sp. ♀, fore wing. d, Polistes dominula ♀, fore wing. e, Jugurtia sp. ♀, antenna.f, Celonites abbreviatus ♀, metasoma. g, Jugurtia sp. ♀, metasoma.h, Paragymnomerus spiricornis ♀, tarsal claws. i, Vespa crabro ♀, tarsal claws. j, Katamenes arbustorum ♂, head. k, Vespa crabro ♀, head.

Fig. 2 – a, Raphiglossa spinosa ♀, fore wing. b, Katamenes arbustorum ♂, fore wing. c, Raphiglossa spinosa ♀, mouthparts. d, Katamenes arbustorum ♂, mouthparts.e, Psiliglossa zeppelini ♀, metasoma. f, Raphiglossa spinosa ♀, metasoma. g, Discoelius dufourii ♀, mid tibia.h, Eumenes coarctatus ♂, mid tibia.

Fig. 3 – a, Eumenes mediterraneus ♀, T1. b, Euodynerus dantici ♀, metasoma. c, Allodynerus delphinalis ♂, metasoma. d, Microdynerus longicollis ♂, metasoma. e, Eumenes papillarius ♀, T2. f, Katamenes arbustorum ♂, T2. g, Katamenes arbustorum ♂, head. h, Delta unguiculatum ♀, head. i, Katamenes arbustorum ♂, fore tarsi.

Fig. 4 – a, Ischnogasteroides picteti tenuis ♀, T1. b,Delta unguiculatum ♀, T1. c, Alastor atropos ♀, fore wing. d, Alastor atropos ♀, tegula.e, Tropidodynerus flavus ♂, tegula. f, Allodynerus delphinalis ♂, tegula.g, Tropidodynerus flavus ♂, antenna.

Fig. 8 – a, Odynerus albopictus ♂, gena. b, Odynerus albopictus ♀, metanotum. c, Pareumenes laminatus ♂, propodeum. d, Pareumenes laminatus ♂, T1. e, Ancistrocerus parietinus ♀, T1. f, Symmorphus debilitatus ♂, T1. g, Symmorphus crassicornis ♂, flagellum. h, Ancistrocerus maroccanus ♂, flagellum.

Fig. 5 – a, Pterocheilus phaleratus ♀, labial palpus. b, Hemipterochilus bembeciformis ♀, labial palpus. c, Onychopterocheilus sp. ♀, labial palpus. d, Tropidodynerus flavus ♀, labial palpus. e, Pterocheilus phaleratus ♀, head. f, Tropidodynerus flavus ♀, mesosoma.

Fig. 6 – a, Tropidodynerus flavus ♀, head. b, Gymnomerus laevipes ♀, head in dorsal view. c, Paragymnomerus spiricornis ♀, head in dorsal view. d, Odynerus poecilus ♀, head. e, Tropidodynerus flavus ♂, metasoma. f, Odynerus spinipes ♀, mesosoma. g, Gymnomerus laevipes ♀, head in frontal view. h, Paragymnomerus spiricornis ♀, head in frontal view.

Fig. 7 – a, Odynerus poecilus ♀, head. b, Paragymnomerus spiricornis ♀, mesoscutum. c, Odynerus poecilus ♀, mesoscutum. d, Paragymnomerus spiricornis ♂, mid femur. e, Odynerus melanocephalus ♂, mid femur. f, Odynerus poecilus ♀, metanotum. g, Odynerus albopictus ♂, mid coxa.

Fig. 9 – a, Eustenancistrocerus blanchardianus ♀, pronotum. b, Ancistrocerus antilope ♀, pronotum. c, Eustenancistrocerus amadanensis ♀, tegula. d, Eustenancistrocerus blanchardianus ♀, tegula. e, Ancistrocerus biphaleratus triphaleratus ♀, tegula. f, Tachyancistrocerus rhodensis ♀, tegula. g, Ancistrocerus biphaleratus triphaleratus ♀, mesosoma. h, Ancistrocerus biphaleratus triphaleratus ♀, T1. i, Tachyancistrocerus rhodensis ♀, mesosoma. j, Tachyancistrocerus rhodensis ♀, T1.

Fig. 10 – a, Chlorodynerus kelidopterus ♂, pronotum. b, Syneuodynerus egregius ♀, pronotum. c, Chlorodynerus kelidopterus ♂, mid and hind legs. d, Syneuodynerus egregius ♀, propodeum. e, Euodynerus posticus ♀, propodeum. f, Euodynerus dantici ♀, propodeum. g, Euodynerus posticus ♀, vertex. h, Euodynerus notatus ♂, mid and hind tarsi. i, Euodynerus semisaecularis ♀, vertex. j, Euodynerus semisaecularis ♂, mid and hind tarsi.

Fig. 11 – a, Leptochilus limbiferus ♀, T2. b, Stenodynerus fastidiosissimus ♀, T2. c, Leptochilus limbiferus ♀, fore wing. d, Stenodynerus fastidiosissimus ♀, fore wing. e, Leptochilus tarsatus ♂, metasoma. f, Microdynerus nugdunensis ♂, metasoma. g, Leptochilus tarsatus ♂, mesosoma. h, Microdynerus nugdunensis ♂, mesosoma.

Fig. 12 – a, Leptochilus limbiferus ♀, tegula. b, Leptochilus tarsatus ♀, tegula. c, Leptochilus regulus ♀, T2. d, Microdynerus parvulus ♀, mandible. e, Microdynerus nugdunensis ♀, mandible. f, Microdynerus parvulus ♂, flagellum. g, Microdynerus nugdunensis ♀, clypeus. h, Microdynerus microdynerus ♀, clypeus.

Fig. 13 – a, Parodontodynerus ephippium ♀, pronotum. b, Pseudepipona lativentris ♀, pronotum. c, Parodontodynerus ephippium ♀, metanotum. d-e, Pseudepipona lativentris ♀, propodeum. f, Pseudepipona lativentris ♀, tegula. g, Pseudepipona herrichii ♂, mandible. h, Antepipona deflenda ♀, metanotum.

Fig. 14 – a, Rhynchium oculatum ♂, mesoscutum and scutellum. b, Rhynchium oculatum ♂, head. c, Rhynchium oculatum ♂, mid femur. d, Stenodynerus fastidiosissimus ♀, mesosoma. e, Stenodynerus fastidiosissimus ♀, tegula and axillary fossa. f, Stenodynerus fastidiosissimus ♀, pronotum. g, Allodynerus delphinalis ♂, mesosoma. h, Allodynerus delphinalis ♂, tegula and axillary fossa. i, Allodynerus rossii ♀, pronotum.

Fig. 15 – a, Polistes dominula ♀, clypeus. b, Polistes dominula ♀, T1. c, Dolichovespula media ♀, clypeus. d, Dolichovespula media ♀, T1. e, Vespa crabro ♀, vertex. f, Dolichovespula media ♀, vertex. g, Vespa crabro ♂, flagellum. h, Dolichovespula norwegica ♂, flagellum.

Fig. 16 – a, Vespa crabro ♀, pronotum. b, Dolichovespula media ♀, pronotum. c, Vespula vulgaris ♀, pronotum. d, Dolichovespula saxonica ♀, malar space. e, Vespula austriaca ♀, malar space.