Chlaenioctenus Bates, 1892

Liu, Ye, Liang, Hongbin, Kavanaugh, David H. & Yang, Maofa, 2010, Key to species of the subgenus Chlaenioctenus (Coleoptera: Carabidae: Chlaeniini: Chlaenius), with description of two new species, Zootaxa 2397, pp. 15-28 : 16-17

Subgenus Chlaenioctenus Bates, 1892

Chlaenioctenus Bates, 1892: 309 ; Kirschenhofer, 2003: 48; Kirschenhofer, 2008: 11

Type species. Chlaenioctenus pectinipes Bates, 1892 , designated by Basilewsky & Grundmann, 1954

Description. Body long-oval, length 13.5 to 16.0 mm, width 5.0 to 6.0 mm. Black with metallic lustre, elytra with two round yellow spots ( Figs. 1, 3 , 5, 7 , 9 , 11, 13, 14). Head moderately large, vertex more or less punctate ( Figs. 20–25 ); eyes large and prominent; antennae long, antennomeres 1–3 sparsely pubescent, antennomeres 4–11 densely pubescent, antennomere 1 distinctly cylindrical, antennomere 3 elongated, slightly shorter than antennomeres 1 and 2 combined, longer than antennomere 4; clypeus and labrum emarginate at apex; labrum with six setigerous punctures near apex; mandible triangle, faintly hooked at apex; palpi glabrous, apical labial palpomere moderately rhombic in male ( Fig. 16 ), cylindrical and slightly compressed in female ( Fig. 17 ); mentum tooth distinct, rounded at apex ( Figs. 26–28 ); glossal sclerite with two subapical setae; gula glabrous. Pronotum ovoid ( Figs. 29–34 ), truncated at apex and base, disk more or less punctate, pubescent or not, hind angle with one seta. Scutellum triangular, glabrous, with fine microsculptures. Elytra elongate, pubescent, apex of elytra more rounded in females than in males; intervals with distinct microsculpture; striae shallow, punctate; shoulders rounded. Hind wings reduced, brachypterous ( Fig. 18 ). Proepisterna smooth or sparsely punctate. Prosternal process bordered, with short setae. Metaepisterna coarsely punctate, pubescent or not, with a longitudinal furrow near outer margin. Abdominal sterna pubescent, sterna 3 to 5 with a long seta on each side, sternum 6 with one seta on each side in male, two in female. Front femora with one tooth on inner margin in male ( Fig. 19 ), without tooth in female; tarsi glabrous dorsally, pro-tarsi with basal three tarsomeres dilated in male; claws pectinate ( Figs. 40–43 ).

Geographical distribution. India, Myanmar, Tailand, China. The collecting sites of Chlaenius (Chlaenioctenus) species are shown in Fig. 53 . This subgenus is widely distributed in the South Asia; but the distributions of individual species are apparently restricted to very small areas. This is probably reflective of low dispersal ability due to reduced (non-functional) hindwings.

Biology. Adults of this species have been collected along roads at night and by use of pitfall traps. Although the hind wings are reduced and nonfunctional in all specimens examined, several specimens had been collected under lights at night. It is most likely that they walked or ran to the lights to feed on prey attracted to the lights.

Remarks. Based on the metallic body surface, single supraorbital seta, antennae with antennomere 3 longest and antennomeres 4–11 densely pubescent, Chlaenioctenus can be recognized easily as a member of genus Chlaenius . Adults of the subgenus are mostly similar to those of subgenera Lissauchenius and Ocybatus of genus Chlaenius in general body shape in having a round yellow spot on each elytron, but different from them and those of other subgenera in having pectinate claws, which are unique in the genus.

Figures

FIGURE 53. Geographical distribution of Chlaenioctenus species. BI, C. bilyi; EN, C. eneides; FR, C. freyi; PE, C. pectinipes; PI, C. piligenys; RO, C. rotundithorax; SC, C. schillhammeri; SE, C. sehnali.

FIGURES 1 – 4. Chlaenius piligenys sp. nov. 1) Holotype, male, dorsal view. 2) Holotype, male, ventral view. 3) Paratype, female, dorsal view 4) Paratype, female, ventral view. Scale line = 5.0 mm.

FIGURES 5 – 8. Chlaenius rotundithorax sp. nov. 5) Holotype, male, dorsal view. 6) Holotype, male, ventral view. 7) Paratype, female, dorsal view. 8) Paratype, female, ventral view. Scale line = 5.0 mm

FIGURES 9 – 10. Chlaenius pectinipes Bates, 1892. 9) Holotype, male, dorsal view. 10) Holotype, male, ventral view. FIGURES 11 – 12. Chlaenius schillhammeri Kirschenhofer, 2003. 11) Holotype, female, dorsal view. 12) Paratype, female, ventral view. Scale line = 5.0 mm.

FIGURES 20 – 25. Heads of Chlaenius (Chlaenioctenus) species. 20) C. piligenys, holotype, white arrow indicating the pubescence on gena. 21) C. rotundithorax, holotype. 22) C. pectinipes, holotype. 23) C. freyi, holotype. 24) C. freyi, IOZ. 25) C. schillhammeri, holotype. Scale line = 1.0 mm.

FIGURES 16 – 19. Character states of Chlaenius (Chlaenioctenus) species. 16) Apical labial palpomere of C. piligenys; holotype, male. 17) Apical labial palpomere of C. piligenys, paratype, female. 18) Reduced hindwing of C. rotundithorax (in yellow circle), holotype. 19) Tooth of front femora of C. piligenys (indicated by red arrow), holotype. Scale lines: A = 0.5 mm (Figs. 16, 17); B = 1.0 mm (Fig. 18); C = 1.0 mm (Fig. 19).

FIGURES 26 – 28. Mentum of Chlaenius (Chlaenioctenus) species. 26) C. piligenys, holotype. 27) C. rotundithorax, holotype. 28) C. pectinipes, holotype. Scale line = 1.0 mm

FIGURES 29 – 34. Pronotum of Chlaenius (Chlaenioctenus) species. 29) C. piligenys, holotype. 30) C. rotundithorax, holotype. 31) C. pectinipes, holotype. 32) C. freyi, holotype. 33) C. freyi, IOZ. 34) C. schillhammeri, holotype. Scale line = 1.0 mm.

FIGURES 40 – 43. Claws of Chlaenius (Chlaenioctenus) species. 40) C. piligenys, holotype. 41) C. rotundithorax, holotype. 42) C. pectinipes, holotype. 43) C. freyi, IOZ. Scale line = 0.5 mm.