Key to the Male Lycus sp. of Southern Africa (after Stamhuis 1992)

  1. Legs thickened, femora and tibiae toothed (at least one pair of legs)......................................................................................................................................................................................... 2
  2. All legs simple............................................................................................................................................................... 7
  3. Forelegs thickened and toothed (femora and tibia); middle and hind legs simple.................................... 3
  4. Hind and/or mid-legs thickened and toothed; forelegs simple....................................................................... 4
  5. Elytra elongated (sub-parallel) Length 8 – 10 mm .......................................................................L chirindanus

    • Elytra sides broadly, dilated (forming wings), posterior roundly dilated Length 13 – 18 mm .............................................................................................................................................................. L humerosus .

  6. Hind and mid-legs thickened and toothed (fore legs simple)....................................................................... 5
  7. Hind legs thickened and toothed (fore and mid legs simple), elytra with slight humeral crests; slightly roundly, dilated latero- posteriorly, with extremities pointing inwards suturally Length 12.5 – 18 mm ......................................................................................................................................................................... L podagricus
  8. Elytra with dilated sides (semi-circular in form), with prominent humeral crests Length 9 – 22 mm ........................................................................................................................................................................... L rostratus
  9. Elytra elongated, without prominent humeral crests ............................................................................................. 6
  10. Elytra slightly broader apically, extremities rounded; distinct scutellar black markings Length 9 – 20 mm ............................................................................................................................... L rostratellus

    • Elytra with slightly rounded dilated latero-humeral margins; posterior slightly dilated, with ovally rounded extremities Length 11.5 – 16 mm ...........................................................L scapularis

  11. Elytra elongated (sub-parallel), without humeral crest; elytra of males and females similar (no sexual dimorphism) .................................................................................................................................. 30
  12. Elytra of males and females of different form (sexually dimorphic characteristics), with or without prominent humeral crests and dilated laterally (varying in form) ........................................... 8
  13. With humeral crest ................................................................................................................................................... 9
  14. Without humeral crest ............................................................................................................................................ 19
  15. Humeral crest spiniform ......................................................................................................................................... 10
  16. Humeral crest not spiniform .................................................................................................................................. 11
  17. Extremities truncate ................................................................................................................................................ 12
  18. Extremities rounded ................................................................................................................................................ 16
  19. Elytra sides dilated medio – laterally .................................................................................................................. 17
  20. Elytral sides dilated (sides rounded posteriorly); small humeral crests Length 9 – 15 mm .................................................................................................................................................. L intgripennis
  21. Extremities curved and prominently spiniform; elytra slightly dilated laterally Length 13 – 15 mm .................................................................................................................................... L apicalis *
  22. Extremities truncate to rounded ............................................................................................................................................................................................................................................................................................... 13
  23. Elytral sides broadly dilated, forming “cheeks”; extremities truncate; costae prominent, texture matt (not glabrous) Length 10 – 21 mm ........................................................................ L melanurus
  24. Elytral sides not to broadly dilated (no “cheeks”) ............................................................................................................................................................................................................................................................ 14
  25. Elytral colouration and truncature of extremities very variable; humeral spiniform sides parallel Length 15 – 23 mm ............................................................................................................ L latissimus*
  26. Elytra colouration relatively constant; humeral spiniform sides not parallel, slightly extended ............................................................................................................................................................................... 15
  27. Elytra extremities straight to rounded Length 10 -17 mm.................................................................................................................................................................................................................................... L corniger
  28. Elytra extremities rounded Length 13.5 – 17 mm................................................................................................................................................................................................................................................L integer *
  29. Elytra dilation more or less rounded; humeral crest small, bluntly spiniform; sutural margin straight Length 9.5 – 17 mm .................................................................................................... L intermedius
  30. Elytra transversely dilated; humeral crest produced, ending in a blunt, rounded incurved spine; sutural margin bloated and overlapping medially, with posterior concave sutural margin Length 19 – 23 mm ............................................................................................................................................................................................................................................................................................................................. L alatus
  31. Elytra lateral margin with an array of long dense and conspicuous setae ............................................................................................................................................................................................................ 18
  32. Elytra lateral margin without setae ......................................................................................................................................................................................................................................................................................... 19
  33. Humeral crests elongately dilated laterally; posterior 1/3 of elytra black Length 10 -16.5 mm.... L haagi - Humeral crests roundy dialated laterally; posterior ½ of elytra black, with black colouration extending medially to humeral area Length 9 – 10 mm........................................................................................................................................................................................................ L pusillus
  34. Elytra with extremely long and slender spines .................................................................................................................................................................................................................................................................. 20
  35. Elytra without spines ..................................................... ............................................................................................................................................................................................................................................................ 21
  36. Elytra with long, curved latero – humeral spines extending centrally Length 10 – 15.5 mm ....................................................................................................................................................................L hamatus
  37. Eltyra with long, curved sutural marginal spines Length 14.5 – 23.5 ...................................................................................................................................................................................................................... L kolbei.
  38. Elytra with humeral calli Length 9 – 17 mm ................................................................................................................................................................................................................................................... L inornatus.
  39. Elytra without humeral calli ..................................................................................................................................................................................................................................................................................................... 22
  40. Elytra with anterior sides dilated and margins upturned (trough – shaped) ............................................................................................................................................................................................................ 25
  41. Elytra with sides dilated (rounded), margins not trough – shaped ..........................................................................................................................................................................................................................23
  42. Elytra sides ovally – rounded dilated ........................................................................................................................................................................................................................................................................ 27
  43. Elytra with distinct epipleura formed (elytra extended ventrally) ................................................................................................................................................................................................................................ 24
  44. Elytra roundly dilated (varying from extremely to elongated) in anterior ¾ with vary large epipleura ventrally; with “fingerprint form” black marks on elongated posterior extremities Length 18.5 – 21 mm...................................................................................................................................................................................................................................................................................................................... L trabeatus.
  45. Elytra with black “fingerprint” apical markings; form of elytra long and slender Length 18.5 – 21 mm .............................................................................................................................................. L trabeatus.
  46. Elytra not so broardly dilated (elongated), with slight ventral epipleura; transverse black apical markings (margin straight) length 13 – 20 mm ........................................... L subtrabeatus..
  47. Elytra with humeral area concavely hollow; posterior elongated, extremities ovally pointed, medially Length 10 – 17 mm ................................................................................................. L distanti .
  48. Elytra with humeral areas not concavely hollow; extremities pointed ventrally and ovally rounded............................................................................................................................................................. 26
  49. Elytra with anterior sides extremely dilated; sutural margin straight Length 13 – 21 mm ................................................................................................................................................................ L poultoni .
  50. Elytra with anterior sides slightly dialated, posterior margin of “trough” slightly extended, forming a rounded, blunt protrusion: sutural margin convexly overlapping medially Length 12 – 18 mm ........................................................................................................................................................................................................................................................................................................................................ L elevatus .
  51. Elytra slightly depressed dorso-ventrally; sutral margin slightly convex, overlapping medially with posterior extremities widely apart Length 16 – 24 mm ............................................. L duvivieri.
  52. Elytra not depressed dorso-ventrally; sutural margin not convex; extremities not widely separated .................................................................................................................................................................... 28
  53. Elytra extremely dilated laterally (transverse rounded form) sutural margins slightly concave medially Length 15 – 23 mm ............................................................................................. L foliaceus
  54. Elytra not as extremely dilated; sutural margin relatively straight .................................................................................................................................................................................................................................... 29
  55. Posterior margin of pronotum with distinct black band, extending medially; sutural margin “bloatated” medially Length 9.5 – 17 mm .............................................................................. L palliatus

    • Pronotum with black markings medially (no black band on posterior margin) Length 8 – 24 mm ...................................................................................................................................................... L ampliatus .

  56. Elytra with slight humeral crest and distinct black, humero-scutellar area (anterior 1/5) Length 6.5 10 mm .................................................................................................................... ......... L zonatus.
  57. Elytra without slight humeral crest; no black humeral area ........................................................................................................................................................................................................................................... 31
  58. Elytra slightly dilated laterally (ovally – elongated form); black posterior 1/5 of elytra Length 9 – 14 mm ........................................................................................................................... L staudingeri.*.
  59. Elytra completely elongated (not dilated latterally) ................................................................................................................................................................................................................................................... 32
  60. Elytra very elongated with prominent costae Length 14 – 20 mm ............................................................................................................................................................................................................. L agrestis.
  61. Elytra elongated; apical 1/5 black Length 11 – 18 mm .............................................................................................................................................................................................................................. L scrobicollis..

Reference to male genital removed from the Stamhuis 1992 key.
Length of species added based on Stamhuis 1992 text.
Species names with * indicates that they may not occur in southern Africa
All text copied from Stamhuis 1992 no work my own!!!!!!

Posted by fubr fubr, June 10, 2018 10:10

Comments

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Posted by tonyrebelo about 2 years ago (Flag)
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Mike, how do you tell male from female?

Also, are there any distribution records to make ID easier.

Posted by jane_trembath 11 months ago (Flag)
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Hi Jane,
One needs to see the abdomen to determine male and female. Otherwise it helps if they are found mating. There are differences in the elytra, but difficult to determine species.
Have added a distribution table, but it is quite wide.

Posted by fubr 11 months ago (Flag)
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Thanks Mike for the distribution table and for looking at my Lycus obs I posted. I'm trying to differentiate them according to the key and learn the species.

Posted by jane_trembath 11 months ago (Flag)
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I dont see the distribution table?

Posted by tonyrebelo 11 months ago (Flag)
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Telling apart ♂♂ and ♀♀ of Lycus:

Only a rule of thumb, which works as far as rules of thumb work before they become rules of thump:

•• The elytra of ♂♂ are broader (sometimes much, much broader) than those of ♀♀ of the same species. ••
 
@jane_trembath
 

Posted by beetledude 11 months ago (Flag)

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