Lesticus bellus, Fedorenko, 2022

Fedorenko, D. N., 2022, New or little-known Lesticus Dejean, 1828 (Coleoptera: Carabidae: Pterostichini) from Vietnam, Russian Entomological Journal 31 (3), pp. 260-275 : 265

KEY TO SPECIES OF LESTICUS FROM VIETNAM:

1(9) Pronotal basal foveae more or less distinctly punctate or rugose-punctate between basal sulcus and lateral margin. Macropterous; metepisternum distinctly or much longer than wide, length/width ratio over 1.20, mostly 1.25–1.50.

2(5) Body smaller, BL 20–24 mm. Lateral ridge of mesoventrite even, with no tooth in front of mesocoxa. Terminal labial palpomere subtriangular to broadly triangular in male, less so in female.

3(4) Terminal labial palpomere broadly triangular in male and less so in female, mean length/width ratio 0.84 or 0.56, respectively. Pronotal basal foveae rather deep, moderately to very sparsely punctate, rugulose or not, well separated from basal dilation of lateral bead. Forebody dorsum mostly rather deep green and less contrasting with black or indistinctly purplish elytra; or dorsum entirely black. Metatarsal anterolateral carina blunt to (sometimes) missing. BL 20–23 mm ................. 7. L. buqueti

4(3) Terminal labial palpomere slightly triangular in male and barely dilated toward apex in female, three or two fifths as wide at apex as long, respectively. Pronotal basal foveae superficial, moderately punctate, often vaguely separated from lateral bead. Forebody dorsum more bright metallic, cupreous green; elytra purple green and shiny in male, dull and nearly black in female. Metatarsal anterolateral carina sharp. BL 20–24 mm ................... 8. L. lakhonus

5(2) Body large, BL 22.7–30 mm. Lateral ridge of mesoventrite with a small precoxal tooth. Terminal labial palpomere broadly triangular, as wide at apex as long in male, less so in female, lp3W/L 0.6–0.8.

6(7, 8) Dorsum black or pronotum very deep green, mostly along sides in basal half. Pronotal basal foveae densely to confluently punctate or rugose-punctate. Elytral striae deep and moderately punctate, intervals convex. Protarsomere 1 with rudimentary ventral pad in female. Internal sac of aedeagus with bulbs c and d contiguous or almost so, bulb b with a small bulb bb at base of right side ( Figs 25–26 ) ................................. 1a. L. praestans praestans

7(6, 8) Same characters, except for elytra black, forebody dorsum mostly deep green. Elytral striae mostly slightly less deep and more finely punctate, intervals slightly less convex. Female protarsomere 1 with rudimentary ventral pad; terminal labial palpomere 3/4–4/5 as wide at apex as long at inner margin. Internal sac of aedeagus with bulbs c and d widely separate, bulb b with no additional bulb ( Figs 27–28 ) ............................................... 2. L. nubilus

8(6, 7) Body contrastingly bicoloured, head and pronotum bright metallic, mostly green or golden green, contrasting sharply with black or slightly violaceous elytra. Elytral striae mostly rather finely punctate, intervals subconvex and shiny in male, more flattened and rather dull in female. Female protarsomere 1 mostly without rudimentary ventral pad; terminal labial palpomere 3/5–2/3 as wide at apex as long at inner margin. Internal sac of aedeagus as for the nominotypical subspecies ............... .............................................. 1b. L. praestans mouhotii

9(1) Pronotal basal foveae smooth. Macropterous or apterous species; metepisternum about as long as or slightly longer than wide, est3L/W≤1.25. Body dorsum bright metallic, mostly contrastingly bicoloured.

10(17) Terminal labial palpomere broadly triangular in male, less so in female, lp3W/L≈1 or ~0.4–0.8, respectively. Lateral ridge of mesoventrite with a small precoxal tooth. Metatarsus not laterally carinate.

11(12) Generally macropterous, with metepisternum longer than wide, length/width ratio 1.13–1.25.Labial palpomere 3 rather narrow in female, lp3W/L 0.36–0.44. Forebody dorsum bright metallic, golden or golden green, elytra mostly black or very slightly violaceous. Protarsomere 1 without ventral pad in female. BL 25.3–31.2 mm. Internal sac of aedeagus as in Figs 31–32 .......... 3. L. auricollis

12(11) Apterous, with metepisternum as long as wide. Labial palpomere 3 wide in female, lp3W/L 0.56–0.80.

13(16) Body robust, PW/PL 1.33–1.50, EL/EW 1.44–1.57. Labial palpomere 3 wide in female, lp3W/L 0.72–0.79.

14(15) Body large, BL 27.8–32 mm. Dorsum contrastingly bicoloured: head golden green or cupreous green, pronotum golden, slightly cupreous, elytra bright violaceous, with three discal setae each. Antennal pedicel with one, long, fixed seta (ventral). Protarsomere 1 with rudimentary or no ventral pad in female. — Central Vietnam and Laos..................................................... 4. L. bellus sp.n.

15(14) Body smaller, BL 22.8–25 mm. Dorsum less contrastingly bicoloured: head and pronotum cupreous, elytra rather deep purple to violaceous, with 1–2 discal setae, d1 or d1 and d2, each. Antennal pedicel with 1–2 short verticillate setae additional to long ventral seta. Protarsomere 1 without ventral pad in female. — Central Vietnam............................................ 5. L. verticillatus sp.n.

16(13) Body slender, PW/PL 1.27–1.32, EL/EW 1.58–1.73. Labial palpomere 3 narrower, lp3W/L 0.87–0.97 (♂) or 0.56–0.63 (♀). Dorsum contrastingly bicoloured: forebody bright metallic, head green, pronotum cupreous green, more cupreous along sides in basal half, elytra deep violaceous to black. Protarsomere 1 with rudimentary ventral pad in female .................. 6. L. attenuatus sp.n.

17(10) Terminal labial palpomere narrow, distinctly longer at inner margin than wide at apex, lp3W/L 0.6 (♂) or 0.4 (♀). Lateral ridge of mesoventrite without precoxal tooth. Metatarsus with a sharp anterolateral carina. Pronotal basal foveae very shallow, not or barely separated from basal dilation of lateral bead. Dorsum bright metallic, head and pronotum green, the latter with golden or cupreous reflections along sides, elytra purple, reflexed lateral margin violaceous. Protarsomere 1 with rudimentary ventral pad in female. — Northern Vietnam (Tam Dao).................................................... 9. L. laevis sp.n .

Figures

Figs 25–39. Aedeagus: 25–26 — Lesticus praestans mouhotii; 27–28– L. nubilus; 29–30, 38–39 — L. attenuatus sp.n., paratypes; 31– 32, 35 — L. auricollis; 33–34, 36 — L. bellus sp.n., paratype; 37 — L. verticillatus sp.n., paratype; 25–34 — median lobe with everted and inflated internal sac; 25, 27, 29, 31, 33 — caudal aspect; 26, 28, 30, 32, 34 — anterodorsal aspect; 35–39 — right paramere, left aspect; a, b, bb, c, cd, d, e, ed, ev, f — bulbs of internal sac. Scale bars 2 mm (25–34) or 1 mm (35–39). Рис. 25–39. Эдеагус: 25–26 — Lesticus praestans mouhotii; 27–28– L. nubilus; 29–30, 38–39 — L. attenuatus sp.n., паратипы; 31– 32, 35 — L. auricollis; 33–34, 36 — L. bellus sp.n., паратип; 37 — L. verticillatus sp.n., паратип; 25–34 — среднЯЯ долЯ с вывернутым и надутым внутренним меШком; 25, 27, 29, 31, 33 — каудально; 26, 28, 30, 32, 34 — антеродорЗально; 35–39 — праваЯ парамера, слева; a, b, bb, c, cd, d, e, ed, ev, f — пуЗыри внутреннего меШка. МасШтаб: 2 мм (25–34) или 1 мм (35–39).