Xorides Latreille, 1809

Sun, Shu-Ping, Lü, Jun, Broad, Gavin R., Li, Tao & Sheng, Mao-Ling, 2023, Two new species of Xorides Latreille (Hymenoptera, Ichneumonidae) from China, with notes on biology and a key to species known from China, European Journal of Taxonomy 890 (1), pp. 115-135 : 117-124

Genus Xorides Latreille, 1809

Xorides Latreille, 1809: 4 .

Type species

Ichneumon indicatorius Latreille, 1806 .

Diagnosis

Mandible unidentate ( Figs 21–22 ). Subapical portion of female flagellum elbowed or bent, on the outer profile of the elbow or bend several “peg-like bristles” ( Figs 13 , 25 ). Epomia usually strong, dorsally projecting sharply as a tooth ( Fig. 26 ). Fore wing with areolet absent. Front tibia usually thickened. Tarsal claws small, simple. Area superomedia of propodeum ( Figs 16 , 28 ) usually complete, hexagonal, or pentagonal. Second tergite with paired oblique baso-lateral grooves ( Fig. 18 ). Lower valve of ovipositor with several almost vertical to distinctly oblique ridges.

Females of Xorides have more or less well-developed fore and mid tibial swellings, often accompanied by grooves, which are associated with enlarged subgenual organs used for detecting vibrations; the adult females are thought to detect hosts through vibrational sounding, tapping the wood with the antennal pegs (which are solid cuticle) and detecting potential hosts in galleries or tunnels via differences in the returning ‘echoes’ ( Broad & Quicke 2000).

Key to the species of Xorides known from China

1. Fore wing with vein 1cu-a opposite or distal to M&RS. Distance between 2rs-m and 2m-cu usually longer than 2rs-m, or 2rs-m almost obliterated ................................................................................ 2

– Fore wing with vein 1cu-a distinctly basal to M&RS. Distance between 2rs-m and 2m-cu shorter than 2rs-m ....................................................................................................................................... 39

2. Anterior profile of fore trochantellus without tooth ......................................................................... 3

– Anterior profile of fore trochantellus with distinct tooth ................................................................ 32

3. Females ............................................................................................................................................. 4

– Males ............................................................................................................................................... 22

4. Mesosoma and tergites black, without white or yellowish white flecks ..............................................5

– Mesosoma and/or tergites with distinct white or yellowish white flecks, or tergites 1 and 2 red .....11

5. Occipital carina absent dorsomedially .............................................................................................. 6

– Occipital carina complete ................................................................................................................. 9

6. Area basalis separated from area superomedia by distinct carina. First tergite approximately 3.6 × as long as posterior width .............................................................. X. longicaudus Sheng & Wen, 2008

– Area basalis and area superomedia confluent, without carina between them. First tergite at most 2.5 × as long as posterior width ........................................................................................................ 7

7. Ovipositor sheath approximately 0.6–0.7 × as long as fore wing. Fore wing with dark spot under pterostigma ....................................................................................... X. furcatus Liu & Sheng, 1998

– Ovipositor sheath at least as long as fore wing. Fore wing without dark spot ................................. 8

8. Malar space as long as basal width of mandible. First tergite 2.4× as long as posterior width; latero-median carinae strong. Frontal orbit black .................................... X. erigentis Wang & Gupta, 1995

– Malar space at most 0.8× as long as basal width of mandible. First tergite 3.1 × as long as posterior width; latero-median carinae absent. Frontal orbit white ........................ X. deplanatus Sheng, 2006

9. Labial palp with apical 3 segments short and very thick; median portion of apical segment strongly subspherically swollen dorsally, apical portion very small and acute. Propodeum with area superomedia and area petiolaris confluent ....................................... X. tumidus Sheng & Wen, 2008

– Labial palp unspecialized. Propodeum with area superomedia separated from area petiolaris by carina ............................................................................................................................................... 10

10. Fore and mid tibiae noticeably stout, clavate. Area externa of propodeum with oblique longitudinal wrinkles. Lateral carinae of area basalis combined posteriorly as a median longitudinal carina ....... ........................................................................................................ X. pissodius Sheng & Wen, 2008

– Fore and mid tibiae unspecialized, not noticeably stout and clavate. Area externa of propodeum ( Fig. 28 ) irregularly reticulate. Lateral carinae of area basalis not combined posteriorly as a median longitudinal carina ................................................... X. kuandianense Sheng, Broad & Sun sp. nov.

11. Latero-median carinae of first tergite reaching posterior margin ................................................... 12

– Latero-median carinae of first tergite not reaching posterior margin, usually reaching mid-length of tergite .............................................................................................................................................. 16

12. Mesosoma and tergites usually with yellowish white and red flecks. Antenna with flagellomeres 10–11 (12) white ............................................................................ X. praecatorius (Fabricius, 1793)

– Mesosoma without white flecks. Posterolateral portions of tergites 4–6 often distinctly white or yellow. Antenna with at least four flagellomeres white .................................................................. 13

13. Outer profile of hind tibia with strong spines. Tergites black, posterior margins of tergites 2–6 yellow ................................................................................. X. nigrimaculatus Zong & Sheng, 2009

– Outer profile of hind tibia without spines. Anterior tergites red, or posterolateral portions of tergites 4–6 white ........................................................................................................................................ 14

14. Tergites 4–6 without white flecks. Anterior tergites red ............... X. sepulchralis (Holmgren, 1860)

– Tergites 4–6 with large white postero-lateral flecks. Anterior tergites black or red ....................... 15

15. Propodeum ( Fig. 1 ), and mesopleuron ( Fig. 3 ) tergite 1 red .............................................................. ...................................................................................... X. cinnabarius Sheng & Hilszczański, 2009

– Mesosoma, propodeum and tergite 1 black ....................................... X. sapporensis (Uchida, 1928)

16. Frons with dense transverse wrinkles. Fore wing with dark spot beneath pterostigma. Tergites 1–2 red ........................................................................................................ X. irrigator (Fabricius, 1793)

– Frons with fine punctures, without wrinkles. Fore wing without dark spot. Tergites with different colour pattern .................................................................................................................................. 17

17. Clypeus without wrinkles. Tergites with or without yellow spots, anterior tergites black ............. 18

– Clypeus ( Fig. 2 ) with dense transverse wrinkles. Tergites with yellow spots, or anterior tergites red ......................................................................................................................................................... 21

18. Antenna with white or yellowish white ring. Subposterior tergites with wide white spots ........... 19

– Antenna without white or yellowish ring. Tergites without white spots ........................................ 20

19. Head, mesosoma and tergites 1–2 with large white spots. At least proximal half of hind coxa red. Hind femur with at least proximal 0.7 reddish brown, distally black ................................................. ................................................................................................... X. centromaculatus Cushman, 1933

– Head, mesosoma and tergites 1–2 and hind coxa entirely black. Proximal half of hind femur almost entirely black, distally brown ..................................................................... X. benxicus Sheng, 2012

20. Hind wing vein 1-cu longer than cu-a. Lateral portion of face widely white. Gena almost entirely red. Tergite 1 partly brownish red ........................................... X. brachylabis (Kriechbaumer, 1889)

– Hind wing vein 1-cu shorter than cu-a. Face and gena more or less entirely black, at least without distinct white spots. Tergite 1 almost entirely black ............................... X. ater (Gravenhorst, 1829)

21. Malar space 0.9× as long as basal width of mandible. Tergite 1 1.6× as long as posterior width. Mesopleuron ( Fig. 4 ) with dense punctures and gray setae. Tergites 1–3 red to darkish red; tergites 4–6 largely white posterolaterally ....................................... X. asiasius Sheng & Hilszczański, 2009

– Malar space 0.5 × as long as basal width of mandible. Mesopleuron smooth, lower portion with weak punctures. Tergite 1 1.2 × as long as posterior width. Tergites 1 laterally and subsequent tergites posteriorly yellow ........................................................................... X. asperus Wang & Gupta, 1995

22. Pterostigma short and wide, 3.0× as long as wide ......................................................................... 23

– Pterostigma narrow and elongate, at least 4.0× as long as wide .................................................... 28

23. Flagellomeres with long setae, which at least as long as or longer than diameter of flagellomere .... ......................................................................................................................................................... 24

– Flagellomeres with shorter setae, which are distinctly shorter than diameter of flagellomere ....... 26

24. Area basalis of propodeum rectangular, 0.6 × as long as area superomedia. Fore and mid tibiae brown to yellowish brown. Eye orbits white ........................................ X. hirtus Liu & Sheng, 1998

– Area basalis of propodeum triangular, 0.9× as long as area superomedia. Fore and mid tibiae brownish black. Eye orbits different coloration .............................................................................. 25

25. Area basalis of propodeum trapezoidal, lateral longitudinal carinae not combined; costula connecting with area superomedia before its middle. Apical portion of each flagellomere not swollen, setae approximately as long as width of flagellomere ................................ X. sapporensis (Uchida, 1928)

– Area basalis of propodeum triangular, posterior portion of lateral longitudinal carinae combined; costula connecting with area superomedia at its middle. Apical portion of each flagellomere swollen, with setae approximately 3.5× as long as width of flagellomere ............... X. benxicus Sheng, 2012

26. Mesosoma and tergites black ......................................................... X. praecatorius (Fabricius, 1793)

– Mesosoma and tergites at least partly red ....................................................................................... 27

27. Mesosoma black. Tergites 1–2 red ....................................................... X. irrigator (Fabricius, 1793)

– Mesosoma laterally and propodeum at least partly red. Tergites 1–2 black, or posterior margin of tergite 1 slightly red ..................................................... X. cinnabarius Sheng & Hilszczański, 2009

28. Latero-median carina of tergite 1 complete, reaching posterior margin of tergite ......................... 29

– Latero-median carina of tergite 1 at most reaching to 0.6 of tergite ............................................... 30

29. Antenna with white ring. Dorsomedian portion of occipital carina absent ........................................ ....................................................................................................... X. sepulchralis (Holmgren, 1860)

– Antenna without white ring. Occipital carina complete ........... X. centromaculatus Cushman, 1933

30. Face entirely black .......................................................................... X. aculeatus Liu & Sheng, 1998

– Face at least partly white ................................................................................................................ 31

31. Face entirely white .................................................................. X. brachylabis (Kriechbaumer, 1889)

– Face with mostly black ........................................................................... X. ater (Gravenhorst, 1829)

32. Tergite 1 at least 3.5 × as long as posterior width ........................................................................... 38

– Tergite 1 at most 3.2× as long as posterior width ........................................................................... 33

33. Antenna with 23–24 flagellomeres. Malar space as long as basal width of mandible. Ovipositor sheath about as long as body. Tergites 1–2 and anterior half of tergite 3 brown ................................ ............................................................................................................... X. tuqiangensis Sheng, 1998

– Antenna with at least 28 flagellomeres. Other characters different ................................................ 34

34. Propodeum usually without lateral longitudinal carina, if lateral longitudinal carina present anteriorly, then body very long and slender ..................................................................................................... 35

– Propodeum at least between anterior edge and spiracle with distinct lateral longitudinal carina. Body stout .................................................................................................... X. hiatus Wang & Gupta, 1995

35. Body stout. Tergite 5 ( Fig. 5 ) particularly short as narrow transverse margin. Antenna with white ring. Hind femur black .................................................................................................................... 36

– Body very slender. Tergite 5 ( Fig. 6 ) not particularly short, approximately 0.35 × as long as posterior width. Antenna without white ring. Hind femur dark brown ......................................................... 37

36. Occipital carina complete. Lower portion of gena with dense oblique wrinkles and sparse punctures; upper portion of gena with relatively dense punctures. Maxillary and labial palpi dark brown. Fore coxa brown ............................................................................................... X. funiuensis Sheng, 1999

– Occipital carina absent dorsally. Gena with sparse fine punctures, without wrinkles. Maxillary and labial palpi beige. Fore coxa yellowish brown ....................................... X. jiyuanensis Sheng, 2004

37. Body very slender. Ovipositor sheath 1.3–1.4 × as long as fore wing. Hind coxa predominantly red. Hind femur dark brown ...................................................................... X. rusticus (Desvignes, 1856)

– Body relatively stout. Ovipositor sheath 1.7–1.8× as long as fore wing. Hind coxa and femur entirely black ...................................................................................................... X. jakovlevi (Kokujev, 1903)

38. Gena partly darkish red. Hind coxa and femur entirely red. Tergites 1 and 2 entirely black ............. ............................................................................................................ X. rufipes (Gravenhorst, 1829)

– Gena partly yellowish white. Hind coxa blackish red. Hind femur entirely piccous black, at most basal portion red. Basal portion of tergite 1 and median portion of tergite 2 widely white ............... ......................................................................................................... X. immaculatus Cushman, 1933

39. Posterior transverse carina of mesosternum complete. Subapical curve of female flagellum usually involving 3 flagellomeres ............................................................................................................... 40

– Posterior transverse carina of mesosternum incomplete. Subapical curve of female flagellum sharply angled between two flagellomeres .................................................................................................. 44

40. Tergites 1 ( Fig. 7 ) stout, at most 2.5× as long as posterior width. Tergites 4–6 ( Fig. 8 ) very short as narrow transverse margin, hind margins distinctly elevated, white ................................................ 41

– Tergites 1 slender, at least 3.0× as long as posterior width. Tergites 4–6 relatively long, hind margins not elevated, entirely black ............................................................................................................. 42

41. Area basalis separated from area superomedia by distinct carina. Area superomedia distinctly convergent anteriorly. Tergite 1 evenly convex, without groove, black. All coxae black .................. ............................................................................................................................. X. weii Sheng, 2002

– Area basalis and area superomedia confluent, without carina between them. Area superomedia with lateral sides parallel. Apical portion of tergite 1 with deep oblique groove, yellowish brown. Fore and mid coxae yellowish brown; hind coxa reddish brown ............................................................... .............................................................................. X. exquisitus ceylonicus Gupta & Chandra, 1977

42. Head partly black. Mesosoma and tergites partly red .............. X. exmacularis Wang & Gupta, 1995

– Head, mesosoma and tergites entirely black ................................................................................... 43

43. Frons with dense transverse wrinkles. Notaulus deep, relatively wide. Vein 2m-cu slightly distal of 2rs-m. Tergite 2 punctate, without wrinkles. Hind leg with femur red and tarsus black .................... ............................................................................................................. X. propinquus (Tschek, 1869)

– Frons with fine punctures. Notaulus ( Fig. 14 ) weak, thin. Vein 2m-cu far distal of 2rs-m ( Fig. 9 ), distance between 2rs-m and 2m-cu 1.4× as long as 2rs-m. Tergite 2 ( Fig. 18 ) with longitudinal wrinkles centrally. Hind leg with femur ( Fig. 9 ) brownish black, and tarsus grayish yellow ............ ........................................................................................... X. juglanse Sheng, Broad & Sun sp. nov.

44. Front profiles of fore and mid trochantelli without teeth ................................................................ 45

– Front profiles of fore and mid trochantelli each with one tooth ..................................................... 48

45. Median portion of ovipositor sheath white ..................................................................................... 46

– Ovipositor sheath monochrome, black or black-brown .................................................................. 47

46. Metapleuron and propodeum black .................................................. X. amissiantennes Wang, 1997

– Metapleuron and propodeum red brown ......................................... X. propodeum ( Cushman, 1933)

47. Face evenly convex, with weak fine punctures. Tergite 1 2.4× as long as posterior width ................ ................................................................................................................. X. abaddon (Morley, 1913)

– Face strongly convex, with rough transverse wrinkle-punctures. Tergite 1 2.0× as long as posterior width .............................................................................................. X. rufipleuralis ( Cushman, 1933)

48. Body shining metallic blue or purple .............................................................................................. 49

– Body not blue or blue-purple, without metallic shiny .................................................................... 52

49. Body shining metallic purple. Wings dark brown, beneath pterostigma with a large hyaline mark .. .............................................................................................................. X. formosanus (Sonan, 1936)

– Body shining metallic blue to blue-black. Wings slightly brownish, hyaline, at least at intercubitus with darkish brown fleck ................................................................................................................ 50

50. Mesosoma and tergites blue. Face, orbits, malar space and tegula entirely dark blue. Flagellomeres 10–12 yellow ....................................................................... X. nigricaeruleus Wang & Gupta, 1995

– Tergites and sometimes mesosoma with white or yellow bands or flecks. Inner orbit white. Tegula white or reddish brown. Flagellomeres without yellow or flagellomeres 10–16 white .................. 51

51. Tegula reddish brown. Posterior bands of tergites 1–2 and posterior margins of tergites 3–5 narrowly yellow. Subapical portion of ovipositor sheath widely white .......... X. elizabethae (Bingham, 1898)

– Tegula white. Anterior 0.3 and posterior large fleck of tergite 1 and posterior half of tergite 2 white. Posterior flecks of tergites 3–6 yellowish. Ovipositor sheath without white ...................................... ............................................................................................................ X. mindanensis Baltazar, 1961

52. Mesosoma and propodeum reddish brown. Tergite 2 with oblique grooves, not forming a rhombic shape, sculpture obliquely aciculate .................................... X. citrimaculatus Wang & Gupta, 1995

– Mesosoma and propodeum black. Tergite 2 with grooves delimiting a large rhombic shape, transversely aciculate ......................................................................... X. albimaculatus Sheng, 1999

Figures

Figs 20–22. Xorides kuandianense Sheng, Broad & Sun sp. nov., holotype, ♀ (CBDPC). 20. Habitus, lateral view. 21. Head, anterior view. 22. Head, lateral view.

Figs 12–15.Xorides juglanse Sheng, Broad & Sun sp. nov., holotype, ♀ (CBDPC). 12. Head, dorsal view. 13. Apical portion of antenna, lateral view. 14. Mesoscutum and scutellum, dorsal view. 15. Mesosoma, lateral view.

Figs 23–26. Xorides kuandianense Sheng, Broad & Sun sp. nov., holotype, ♀ (CBDPC). 23. Head, dordal view. 24. Head, dorsoanterior view. 25. Apical portion of antenna, lateral view. 26. Mesoscutum, dorsal view.

Figs 16–19. Xorides juglanse Sheng, Broad & Sun sp. nov., holotype, ♀ (CBDPC). 16. Propodeum, dorsal view. 17. Tergite 1, dorsal view. 18. Tergites 2–4, dorsal view. 19. Apical portion of ovipositor, lateral view.

Figs 27–30. Xorides kuandianense Sheng, Broad & Sun sp. nov., holotype, ♀ (CBDPC). 27. Mesosoma, lateral view. 28. Propodeum, dorsal view. 29. Metasoma, dorsal view. 30. Apical portion of ovipositor, lateral view.

Figs 1–4. 1, 3. Xorides cinnabarius Sheng & Hilszczanski, 2009, holotype, ♀ (CBDPC). 2, 4. X. asiasius Sheng & Hilszczanski, 2009, holotype, ♀ (CBDPC). 1. Propodeum, dorsal view. 2. Clypeus. 3–4. Mesosoma, lateral view.

Figs 5–6. Metasoma. 5. Xorides funiuensis Sheng, 1999, holotype, ♀ (CBDPC). Lateral view. 6. X. jakovlevi (Kokujev, 1903), ♀ (CBDPC). Dorsal view.

Figs 7–8. Xorides weii Sheng, 2002, holotype, ♀ (CBDPC). 7. Metasoma, dorsal view. 8. Posterior portion of metasoma, dorsal view.

Figs 9–11. Xorides juglanse Sheng, Broad & Sun sp. nov., holotype, ♀ (CBDPC). 9. Habitus, lateral view. 10. Head, anterior view. 11. Head, lateral view.