Bostrichidae

Liu, L. Y., Beaver, R. A. & Yang, J. T., 2006, The Bostrichidae (Coleoptera) of Taiwan: a key to species, new records, and a lectotype designation for Sinoxylon mangiferae Chujo, Zootaxa 1307, pp. 1-33 : 2-6

Key to the Species of Bostrichidae of Taiwan

1. Head concealed beneath cowl­like pronotum. Antenna with 3 ­segmented club. Pronotum at least partly rounded at sides .............................................................................. 2

­ Head fully exposed from above. Antenna with 2 ­segmented club. Pronotum flattened, not cowl­like, with complete lateral margins. ( Lyctinae ) ............................................. 3

2. Pronotum evenly rounded anteriorly, without forwardly or ventrally directed horns ( Fig. 1). Body 2.5­3.0 times longer than wide. First tarsal segment subequal in length to second. ( Dinoderinae ) .............................................................................................. 7

­ Pronotum flattened or excavate anteriorly (except in Parabostrychus with rounded anterior margin armed with a row of small teeth, and body nearly four times longer than wide), anterior angles sometimes with forwardly or ventrally directed hooked teeth or processes. Ratio of length to width of body variable. First tarsal segment much shorter than second. ( Bostrichinae ) .................................................................. 10

3. Antennal club with one or both terminal segments elongate, parallel­sided, subtruncate at apex. ......................................................................................................................... 4

­ Antennal club with terminal segment ovoid becoming attenuated toward apex .......... 6

4. Antennal club with both segments elongate and longer than broad; segments of funicle without semierect, scale­like setae, dorsal pubescence composed of irregular thick, semierect setae ................................................................ Lyctoxylon dentatum (Pascoe)

­ Antennal club with only terminal segment elongate, segments of funicle clothed with semierect, scale­like setae; elytra with regular lines of wide, flattened, erect, scale­like setae. ( Minthea , Fig. 2) ................................................................................................ 5

5. Thoracic fovea deeply and distinctly reticulate; lateral margin of pronotum distinctly toothed and with from 7­12 stiff narrow scale­like setae ....... Minthea reticulata Lesne

­ Thoracic fovea punctate, not distinctly reticulate; lateral margin of pronotum rather smooth and with from 13­19 broad scale­like setae .......... Minthea rugicollis (Walker)

6. Terminal antennal segment subequal to penultimate; pronotum slightly narrower than the elytra; sides of pronotum subsinuate, narrowing posteriorly; the pubescence of pronotum composed of fine hairs ( Fig. 3) .......................... Lyctus brunneu s (Stephens)

­ Terminal antennal segment from 1.5­2.0 times as long as penultimate, pronotum distinctly narrower than the elytra; sides of pronotum nearly parallel; the pubescence of pronotum composed of thick hairs and a tuft of thicker hairs around the median fovea ....................................................................................................... Lyctus sinensis Lesne

7. Scutellum transversely rectangular. Pronotum usually with 2 oval depressions near base. Apex of elytra evenly rounded ( Fig. 4). Second antennal segment distinctly shorter than first. ( Dinoderus ) ...................................................................................... 8

­ Scutellum almost square. Pronotum without depressions near base. Apex of elytra angularly rounded ( Fig. 1). Second antennal segment approximately equal in length to first .......................................................................... Rhyzopertha dominica (Fabricius)

8. Antenna with 10 segments. Clypeus with or without long, dense setae. First and second tarsal segments without long, dense setae ventrally .............................................. 9

­ Antenna with 11 segments. Clypeus with long, dense, curved setae laterally. First and second tarsal segments with long, dense setae ventrally ( Fig. 5).................................... ............................................................................................. Dinoderus japonicus Lesne

9. Clypeus with very long dense setae, especially laterally. Antennal segments 1­7 with very long, dense setae. Pronotum with paired basal depressions weak or absent ( Fig. 6) .......................................................................................... Dinoderus ocellaris Stephens

­ Clypeus and antennal segments 1­7 with short, sparse setae. Pronotum with obvious

paired basal depressions ( Fig. 4) ................................... Dinoderus minutus (Fabricius) 10. Intercoxal process of first abdominal ventrite forming a vertical lamina ( Fig. 7). Metepisternum narrowed posteriorly so that metepimeron nearly touches metasternum. (Xyloperthini) .................................................................................................... 11

­ Intercoxal process of first abdominal ventrite broader and with a ventral face ( Fig. 8). Metepisternum more broadly truncate behind with metepimeron widely separated from metasternum ...................................................................................................... 18

11. Pronotum with a distinct carina along lateral margins posteriorly, sharply bent at posterior angles, and slightly prolonged along base ( Fig. 9) ........................................... 12

­ Pronotum without a distinct carina along lateral margins posteriorly ........................ 16

12. First two segments of antennal club elongate, clearly longer than wide. Female frons with dense, erect hairs ( Fig. 10). ( Xylothrips ) ........................................................... 13

­ First two segments of antennal club transverse ( Fig. 11). Female frons without dense, erect hairs. ( Xylopsocus ) ............................................................................................ 14

13. Anterolateral part of pronotum and basal part of pronotal disk smooth, shining, almost impunctate ( Fig. 12) ............................................................ Xylothrips flavipes (Illiger)

­ Anterolateral part of pronotum rugulose, clearly and densely punctured ( Fig. 13), basal part of pronotal disk with distinct, fine punctures medially............................................ .................................................................................... Xylothrips religiosus (Boisduval)

14. Elytral declivity enclosed by raised lateral margin which extends almost to suture dorsally ( Fig. 14). Basal part of pronotum dull, very densely, more coarsely punctured. Elytral disc densely, evenly punctured, sometimes granulate­punctate, the sides in front of declivity similarly but more strongly sculptured .......................................... 15

­ Raised lateral margin obliterated in upper third of elytral declivity ( Fig. 15). Basal part of pronotum smooth, shining, very finely sparsely punctured. Elytral disc almost smooth, rather finely punctured, the sides weakly transversely rugose in front of declivity ( Fig. 15) ................................................ Xylopsocus castanoptera (Fairmaire)

15. Antenna 9 ­segmented. Declivital margin of elytra weakly bisinuate in upper third ( Fig. 14). Elytral declivity strongly punctured, granulate­punctate only in upper third.......... ................................................................................... Xylopsocus capucinus (Fabricius)

­ Antenna 10 ­segmented. Declivital margin of elytra with a sharp, inwardly­directed tooth in upper third. Elytral declivity strongly granulate­punctate over whole surface ( Fig. 16) ............................................................................... Xylopsocus bicuspis Lesne

16. Small species, 2.5­2.7 mm long. Last segments of antennal club recurved towards funicle in most specimens ( Fig. 17). Elytral declivity without spines, lateral margin of declivity with a continuous carina. Female elytral declivity with raised suture forking in apical third of declivity into an inverted Y, the forks almost reaching the lateral margin of the declivity, the triangular space between them shining and impunctate, apical angles of elytra with two small, flattened processes extending horizontally, with minute teeth on their apical margin ( Fig. 18); male declivity without a raised inverted

Y in apical third, and without flattened processes at apical angles. Last visible segment of male abdomen with wide pleural pieces .......................... Xylocis tortilicornis Lesne ­ Larger species, 4­9 mm long. Last segments of antennal club not recurved towards funicle. Elytral declivity with spines, its lateral margin with or without a complete carina. Last visible segment of male abdomen without pleural pieces ...................... 17

17. Body largely dark brown, the bases of pronotum and elytra more or less reddish brown. Elytral declivity in both sexes with two pairs of sharply pointed spines, one pair on the upper margin, the second pair lateral to and a little below the first pair; margin of declivity carinate only in lower half, upper half with a separate thickened longitudinal costa lateral to the second pair of spines ( Fig. 19). Body 6­9 mm long .... ................................................................................... Xyloperthella crinitarsis (Imhoff)

­ Body largely pale yellowish brown, with front of the head, anterior part of pronotum, elytral declivity, metepisternum and metasternum dark brown, and with a brown spot on the side of each elytron in the anterior third. Elytral declivity with a pair of small teeth at the upper margin, and a very large inwardly curving spine on each lateral margin ( Fig. 20), longer in male than female; margin of declivity carinate almost to suture, except where spines are inserted. Body 4­6 mm long ....... Xylodectes ornatus (Lesne)

18. Both mandibles short and blunt, meeting along midline, with directly opposable cutting edges. Antennal club flabellate or with strongly transverse segments. Elytral declivity with 2 strong spines in middle close to or on suture. (Sinoxylini: Sinoxylon ). ..................................................................................................................................... 19

­ Mandibles long and pointed, crossing in midline and cutting like shears. Antennal club not flabellate nor with strongly transverse segments. Elytral declivity without 2 strong spines, or if present, well separated from suture. ( Bostrichini ) .................................. 24

19. Submarginal carina along lateral margin of elytra curving dorsally at its posterior end to join carina forming lower margin of elytral declivity ( Fig. 21). Punctures of elytral disc increasing in size posteriorly, very coarse at upper margin of declivity ( Fig. 22), disc angularly separated from declivity ..................................... Sinoxylon anale Lesne

­ Submarginal carina along lateral margin of elytra continues to run parallel to elytral margin to reach suture ( Fig. 23); margin of elytral declivity rounded. Elytral punctures variable ....................................................................................................................... 20

20. Teeth on elytral declivity contiguous, inserted on sutural interstriae, laterally compressed, triangular, with pointed tips, a prominent costa present on the lateral margin of the declivity at the same level, and another weaker costa more apically and laterally ( Fig. 24). Larger species, 7­9 mm long ................................. Sinoxylon crassum Lesne

­ Teeth on elytral declivity not contiguous, inserted lateral to sutural interstriae, lateral margin of declivity without costae. Smaller species, up to 6 mm long ...................... 21

21. Spines on elytral declivity laterally compressed, triangular, sharply pointed. ........... 22

­ Spines on elytral declivity not laterally compressed, conical with tips acute, or subcylindrical and bluntly tipped ........................................................................................ 23

22. Margin of elytral declivity with three pairs of costae, the uppermost barely distinct, the surface dull, very densely, coarsely, deeply punctured ( Fig. 25). Base of pronotum dull, the median part with densely placed, flattened granules, longitudinally rugulose more laterally ( Fig. 26) .................................................... Sinoxylon mangiferae Chujo

­ Margin of elytral declivity without costae, the surface shining, less densely, more finely and shallowly punctured. Base of pronotum shining, with small, well­separated granules ............................................................................. Sinoxylon pygmaeum Lesne

23. Segments of antennal club strongly flabelliform, the width of the second exceeding the total length of the club. Frons with four minute teeth in a transverse row ( Fig. 27). Spines on elytral declivity conical the tips acute ..... Sinoxylon conigerum Gerstaecker

­ Segments of antennal club less strongly flabelliform, the width of the second less than the total length of the club. Frons unarmed without a row of four minute teeth. Spines on elytral declivity subcylindrical, bluntly tipped ( Fig. 28) ........................................... ............................................................................................. Sinoxylon japonicum Lesne

24. Elytra with a raised longitudinal costa near base and fascicles of dense golden­yellow hairs scattered over elytral surface ( Fig. 29) .......... Lichenophanes carinipennis Lesne

­ Elytra without costa and fascicles of hairs ................................................................. 25

25. Anterior margin of pronotum convex with a row of small teeth. Body very elongate, about 3.7 times longer than wide, elytra about 2.5 times as long as pronotum ( Fig. 30) ................................................................................... Parabostrychus acuticollis Lesne

­ Anterior margin of pronotum straight or concave in middle without teeth on median part. Body less elongate, about three times longer than wide, elytra about twice as long as pronotum ................................................................................................................ 26

26. Pronotum without a broad, transverse depression just behind anterior margin, and anterior angles of pronotum not produced. Median part of frons very finely, very densely punctured, the punctures with short, greyish­yellow, parallel, ventrallydirected, appressed hairs forming a band, frontoclypeal suture deeply impressed across its whole width ( Fig. 31) ................................................ Bostrychopsis parallela Lesne

­ Pronotum with a broad, transverse depression just behind anterior margin, and anterior angles of pronotum produced as hooked or toothed processes. Median part of frons less densely, more coarsely punctured with hairs not forming a dense band ( Fig. 32), frontoclypeal suture not deeply impressed, or deeply impressed only in median third or less. ( Heterobostrychus ) ......................................................................................... 27

27. Frontoclypeal suture deeply impressed in the middle. Posterior angles of pronotum not projecting. Elytra with short, appressed hairs. Male with hook­like processes at apical angles of pronotum, and each elytron with a strong, stout tooth inserted near the declivital margin, its apex obliquely truncate when viewed from above ( Fig. 33). Female with an upcurved tooth at apical angles of pronotum, and tooth on elytral declivity reduced to a rounded callus ( Fig. 34) ............................................................... ........................................................................... Heterobostrychus hamatipennis Lesne