Key to the identification of Mastinocerinae genera with 12-segmented antennae and the first pro- and mesotarsomere with ventral combs

Adapted from Zaragoza-Caballero & Pérez-Hernández (2014), with modifications on couplet 16 and the addition of a new couplet. The key is presented here starting at couplet 12, which includes the Mastinocerinae with 12-segmented antennae and first pro- and mesotarsomere with ventral combs.

12. Only the first pro- and mesotarsomere with ventral combs ......................................................... 13

13. Mandibles without internal teeth ................................................................................................. 14

13’. Mandibles with internal teeth ................................................. Pseudomastinocerus Wittmer, 1963

14. Posterior pronotal margin continuous .......................................................................................... 15

14’. Posterior pronotal margin discontinuous, with medial region projected ......................................... ................................................................................................................. Phrixothrix Olivier, 1909

15. Antennomere IV–XI with double flabellae .................................................................................. 16

15’. Antennomere IV–X with double flabellae, XI enlarged and without flabellae ............................... .................................................................................................... Eurymastinocerus Wittmer, 1976

16. Tarsal combs as long as tarsus ..................................................................................................... 17

16’. Tarsal combs as long as half of tarsus ........................................................................................16a

16a. Labial palpi 2-segmented, tarsomere II as long as half of tarsomere I length ................................. ....................................................................................................................... Iviephengus gen. nov.

16a’. Labial palpi 3-segmented, tarsomere II subequal to tarsomere I length .......................................... .................................................................................................. Cephalophrixothrix Wittmer, 1976

17. Tarsal claws simple, without teeth ............................................................................................... 18

17’. Tarsal claws with thin teeth on claw base ............................................. Ptorthodius Gorham, 1881

18. Labial palpi 3-segmented ............................................................................................................. 19

18’. Labial palpi 2-segmented ............................................................. Mastinomorphus Wittmer, 1976

19. Two large and uneven tentorial pits, clypeus not projected, labrum dorsally visible ...................... ...................................................................................... Mastinocerus (Mastinocerus) Solier, 1849

19’. A single tentorial pit, clypeus projected, labrum not visible dorsally ............................................. .......................................................................... Mastinocerus (Paramastinocerus) Wittmer, 1976