Tylodinus buchanani, Luna-Cozar & Anderson & Jones & León-Cortés, 2014

Luna-Cozar, Jesús, Anderson, Robert S., Jones, Robert W. & León-Cortés, Jorge L., 2014, A taxonomic monograph of the genus Tylodinus Champion (Coleoptera: Curculionidae: Cryptorhynchinae: Tylodina) of Chiapas, Mexico, Zootaxa 3788 (1), pp. 1-63 : 20-22

Tylodinus buchanani species group

Recognition. Species of this species group are distinguished by having the pronotum without impressions. Elytra black, dark red at the base, along the middle line, elytral declivity and flanks; base of the elytral declivity with transverse fringe or band of white scales ( Figures 40–51 ).

Diagnosis. Body approximately 2.1x longer than wide. Head with yellow (four species), light brown (one species) or yellow to light brown scales (one species), surface with punctures similar to punctures on rostrum; vertex with dense to contiguous scales (four species) or overlapping (two species), uniformly distributed along on vertex and yellow (one species), whitish to light brown (one species), whitish to yellow (two species) or similar in coloration and tonality to head scales (one species); frons concave (one species) or moderately concave; rostrum moderately robust, moderately carinate, apical area punctuate (four species) or puncticulate (two species); eyes moderately convex. Pronotum in lateral view strongly convex (four species) or moderately convex (two species), outline with anterior constriction, without posterior constriction ( Figure 10 ); in dorsal with sides slightly divergent from base to midlength, then convergent to apex, constricted beyond the middle ( Figure 14 ); without impression; surface not to weakly granulate, not carinate, punctures small or larger, dense to contiguous at the base and progressively more widely spaced, smaller and shallower to the apex ( Figures 16–17 ); disc clothed with yellow or whitish to light brown scales (one species), very dense on lateral sides and flanks, anterior area forming a thick longitudinal fringe along the middle and a narrow strip that diverges from the middle base to the flanks, and with dark brown or black scales on the middle and posterior areas of the disc ( Figure 14 ). Elytra black, with dark red at the base, along middle line, elytral declivity and flanks ( Figures 40–51 ); with basal margin slightly sinuate ( Figure 3 ) or straight (one species) ( Figure 2 ), with dark scales on disc, scales dense and yellow on declivity at intervals 1–3 and on elytral base, fringe or band of white scales on tubercles of declivity and on intervals 1–7, denser on elytral base and sparsely on rest of elytra; striae 10 complete (four species) or incomplete (two species). Metasternum moderately concave or concave (one species), glabrous; metasternal tooth present (three species) or absent (three species). Male abdomen with ventrites 3–5 not in same plane as ventrite 1–2 (two species with male unknown), ventrite 1 concave (two species), feebly concave (one species) or convex (one species), median section glabrous (three species), with scatter scales (one species) or squamous (one specie); ventrite 2 longer (one species) or as long as ventrites 3–4 combined, median section glabrous (one species), squamous (two species), with a transverse line of scales (two species) or with the line of scales interrupted medially; ventrite 5 convex along median line, as long as ventrite 1, without impressions. Femora armed, hind femora length reaching (three species) or near to elytral apex (three species), tibiae subparallel (four species) or width at baseline (two species), premucro present (three species) or absent (three species). Male genitalia ( Figures 104–107 ) with median lobe in lateral view weakly curved, very slender to stout; in ventral view as long as half length (one species) or equal (one species) to apodeme, lateral sides straight (one species) or convex at the sides at 0.27 from the base (two species) or concave near to middle (one species), convergent, apex acute; apical process in lateral view weakly (two species) to slightly curved (two species), abruptly curved downward, in ventral view not constricted beyond the median orifice, lateral sides convergent to apex. Female genitalia with tergite eight constricted (three species) or trapezoidal (two species), with the apex invaginate (one species) or slightly rounded (four species); sternite eight (missing in T. buchanani ) oblong (one species), sub- trapezoidal (two species) or trapezoidal (one species), with the median membranous area with the median membranous area 1/3 (one species), ½ as long as basal plate (two species) or subapical (one species); spermatheca shallowly (three species) or very shallowly curved (two species), outer margin not convex, ramus indistinct (four species) or long and slender (one species); nodulus indistinct (three species) or slender (two species).

Key to species of Tylodinus buchanani species group

1 Metasternal tooth present ( Figure 19 )...................................................................... 2

- Metasternal tooth absent................................................................................ 4

2(1) Base of elytral declivity with the tubercle on interval 2 smaller than tubercle on interval 4 ( Figures 46–49 ).............. 3

- Base of elytral declivity with the tubercle on interval 2 similar in size to tubercle on interval 4 ( Figures 40–45 )............................................................................................ T. buchanani Luna-Cozar

3(2) Premucro present; elytral declivity without polished area ( Figures 48–49 )....................... T. wibmeri Luna-Cozar

- Premucro absent; elytral declivity with lateral polished area ( Figures 46 )......................... .. T. jonesi Luna-Cozar

4(2) Pronotal punctures large ( Figure 16 )...................................................... T. exiguus Luna-Cozar

- Pronotal punctures small ( Figure 17 )......................................................................5

5(4) Premucro present; elytral basal margin straight, light scales on pronotum frequently whitish, occasionally light brown (Figures 2, 50–51)........................................................................ .. T. variabilis Luna-Cozar

- Premucro absent; elytral basal margin slightly sinuate, light scales on pronotum yellow to light brown with whitish intermixed scales ( Figures 3 , 44–45 )................................................................ T. ixchel Luna-Cozar

Figures

FIGURES 36–43. Dorsal and lateral habitus: 36–37. Tylodinus pseudocavicrus, 38–39. Tylodinus rugosus. 40–41. Tylodinus buchanani. 42–43. Tylodinus exiguus.

FIGURES 44–51. Dorsal and lateral habitus: 44–45. Tylodinus ixchel, 46–47. Tylodinus jonesi, 48–49. Tylodinus wibmeri, 50–51. Tylodinus variabilis.

FIGURES 1–11. 1–5. Dorsal outline: 1. Generalized Tylodinus, indicating terminology used in this study. Key: letters indicate areas of pronotum. A, anterior area; B, median area; C, posterior area; a, anterior of lateral area; b, median section of lateral area; c, median section of dorsal area; d, anterior section of dorsal area; e, posterior section of lateral area; f, posterior section of dorsal area. 2. Tylodinus variabilis, note elytra basal margin straight. 3. Tylodinus ixchel, note elytra basal margin slightly sinuate. 4. Tylodinus immundus, note elytral basal margin sinuate. 5. Tylodinus elongatus, note elytra basal margin very sinuate. 6–11. Lateral outline: 6. Tylodinus complicatus, male, note ventrites 3–5 in same plane as ventrites 1–2. 7. Tylodinus variabilis, male, note ventrites 3–5 not in same plane as ventrites 1–2. 8. Tylodinus coapillensis, female, note ventrites 1–2 strongly convex, ventrites 3–5 not in same plane as ventrites 1–2. 9. Tylodinus zilchi (schematic). 10. Tylodinus sepulturaensis (schematic) 11. Tylodinus rugosus (schematic).

FIGURES 12–19. 12. Tylodinus pusillus head a) male, b) female. 13–14. Dorsal habitus of pronotum showing the lateral side of pronotum 13. Tylodinus andersoni, 14. Tylodinus porvenirensis. 15–17. Dorsal habitus: 15. Tylodinus rugosus, 16. Tylodinus exiguus, 17. Tylodinus jonesi. 18. Tylodinus coapillensis note tubercle on elytra declivity base, 19. Tylodinus elongatus showing metasternal tooth.

FIGURES 100–109. Ventral and lateral habitus of median lobe: 100. Tylodinus andersoni, 101. Tylodinus cavicrus, 102. Tylodinus pseudocavicrus, 103. Tylodinus rugosus, 104. Tylodinus exiguus, 105. Tylodinus ixchel, 106. Tylodinus jonesi, 107. Tylodinus variabilis, 108). Tylodinus leoncortesi, 109. Tylodinus triumforium.