Trichotichnus (Pseudotrichotichnus) vietnamensis, Ito, 2009

Ito, Noboru, 2009, Note on the subgenus Pseudotrichotichnus of the genus Trichotichnus from Southeast Asia (Coleoptera: Carabidae: Harpalini), Acta Entomologica Musei Nationalis Pragae 49 (2), pp. 599-606 : 603-604

Trichotichnus (Pseudotrichotichnus) vietnamensis sp. nov.

( Figs. 3 , 6 )

Type material. HOLOTYPE: J, ‘ Mt. Pia Oac , alt. 1,200m, Cao Bang Prov., N. Vietnam, 23.V.1999, S. Uéno leg.’ ( NMNS) . PARATYPES: 2 ♀♀, same data as the holotype ; 2 JJ 1 ♀, ‘ Sa Pa , alt. 1,550 m, Lao Cai Prov., 10.V.1995, S. Uéno leg. ’; 1 J, ‘ Tam Dao , alt. 960 m, N. Vietnam, 22.IV.1995, S. Uéno leg.’ ( NMNS, NIKJ), 1 ♀, the same locality, 15.V.1995 ; 2 JJ 3 ♀♀, the same locality, ‘ 22.IV.1995, S. Uéno leg. ’; 1 ♀, the same locality, alt. 930m, 21.IV.1995 ’; 2 ♀♀, the same locality, ‘alt. 900m, 16.–23.IV.1991, Strnad Jan leg.’ ( HNHM) ; 1 ♀, ‘ Da Lat , Vietnam, 20.IV.1989, F. Schmidt leg.’ ( DWBG) .

Description. Body oblong, fairly convex, pitchy black though a little lighter than in T. miyakei , strongly shiny, iridescent on elytra; palpi, antennae, tarsi and tibiae light reddish brown, femora brown to blackish brown.

Head rather large, 0.71–0.74 times as wide as pronotum, gently convex, very sparsely and microscopically punctate; labrum subquadrate, triangularly emarginate apically; clypeus transversely elevated, shallowly emarginate at apex; clypeal suture very weakly curved, deep even in middle, more strongly deepened at sides; frontal impressions as deep as clypeal suture at sides, obliquely linear; eyes large, well convex; temples steeply inclined, rather long, one-third the eye length; genuine ventral margin of eyes widely isolated from buccal fissure; antennae short, hardly reaching pronotal base, segment 3 pubescent in apical half, as long as segment 4 and 1.5 times as long as segment 2; labial palpi moderately thick, segment 3 as long as segment 2; ligula slim, slightly thickened apicad; paraglossae narrow, prolonged forwards beyond ligula; mentum with median tooth small and triangular, epilobes not widened apicad; microsculpture mostly invisible in 80× magnification.

Pronotum almost quadrate, widest at apical third, 1.4 times as wide as long, so widely convex that lateral furrows are linearly impressed; sides weakly curved between anterior margin and midlength, obliquely linear elsewhere; anterior margin weakly emarginate, straight in middle, without border in narrow middle area; base with broken border; anterior angles widely arcuate; basal angles obtuse, very narrowly rounded; basal foveae flattened, each with shallow groove; front transverse impression very shallow, hind one also shallow; disc smooth, punctation absent or sparse anteriorly, coarse and moderately dense in basal foveae; microsculpture largely consisting of transverse meshes, and of isodiametric meshes near basal punctures.

Elytra oblong, weakly oval, 1.30 times as wide as pronotum, a little less than 1.50 times as long as wide, evenly convex, very sparsely and microscopically punctate; sides subparallel near midlength, abruptly and arcuately curved posteriorly; apices widely rounded at sides, with tips close to each other; base of each elytron shallowly emarginate, forming rounded angle with lateral margin; striae as in T. (P.) jelineki sp. nov.; intervals gently convex, becoming more convex towards apex and base, discal pore of interval 3 situated between apical third and two-fifths; marginal series widely interrupted medially, composed of 8 + 10 umbilicate pores; microsculpture consisting of fine and obscure transverse lines. Hind wings well developed.

Ventral surface largely impunctate, very sparsely and minutely punctate on lateral areas of metasternum; metepisterna convergent posteriorly, nearly 1.5 times as long as wide; abdominal sternite 6 sparsely pubescent, with two setae at each side in both sexes, apex truncate or feebly emarginate in male and narrowly rounded in female.

Fore tibiae a little more widened apicad than in T. miyakei , sulcate in basal four-fifths, terminal spur expanded in basal third; hind tarsi 0.70–0.74 times as long as the width of head in male and 0.65–0.69 times as long in female, segment 1 0.9 times as long as segments 2 and 3 combined and 1.65 times as long as segment 2, segment 3 1.5 times as long as segment 4, all claws with two setae on outer margin and three setae on inner margin of ventral surface.

Aedeagus ( Fig. 6 ) similar in shape to T. jelineki sp. nov., though less stout, with a little smaller basal bulb; apical orifice widely opened, inner sac not bearing spinose sclerites but with clusters of microtrichia near middle; apical lobe short, thickened at tip.

Body length: 8.8–10.2 mm; body width: 3.6–4.2 mm.

Differential diagnosis. This new species is similar to T. miyakei , but the body is smaller, the legs are paler and the aedeagus bears smaller basal bulb and narrow apical orifice armed with clusters of microtrichia ( Fig. 6 ).

Etymology. The species name is derived from country of type locality.

Distribution. Vietnam.

Figures

Figs. 1–5. 1–2 – Trichotichnus (Pseudtrichotichnus) jelineki sp. nov., holotype (1 – habitus; 2 – male genitalia); 3 – T. (P.) vietnamensis sp. nov.; 4 – T. (P.) tenuitibialis sp. nov.; 5 – T. (P.) niger Louwerens, 1951. Scale bar: 1 mm. Abbreviations: l – lateral aspect, d – dorsal aspect.

Figs. 6–9. Male genitalia. 6 – Trichotichnus (Pseudotrichotichnus) vietnamensis sp. nov.; 7 – T. (P.) tenuitibialis sp. nov.; 8 – T. (P.) niger Louwerens, 1951; 9 – T. (P.) miyakei Habu, 1980. Scale bar: 1 mm. Abbreviations: l – lateral aspect, d – dorsal aspect.