Trichotichnus (Pseudotrichotichnus) vietnamensis Ito 2009, sp. nov.
Creators: name: Ito, Noboru
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Trichotichnus
Trichotichnus vietnamensis

description: 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.
description: Published as part of Ito, Noboru, 2009, Note on the subgenus Pseudotrichotichnus of the genus Trichotichnus from Southeast Asia (Coleoptera: Carabidae: Harpalini), pp. 599-606 in Acta Entomologica Musei Nationalis Pragae 49 (2) on pages 603-604, DOI: 10.5281/zenodo.5320906