Trichotichnus (Bottchrus) bubsaensis, Schmidt, 2017

Schmidt, Joachim, 2017, Brachypterous ground beetles of the Trichotichnus subgenus Bottchrus Jedlička (Coleoptera, Carabidae) from the Himalaya, with description of fifteen new species, Zootaxa 4323 (3), pp. 301-358 : 312-314

Trichotichnus (Bottchrus) bubsaensis sp. n.

(Figs 4, 32–37, 151, 4)

Type material. Holotype: ♂, “ NEPAL: Bubsa / April 1993 / 2300 m n.m. / lgt. T. Wiesner ” (cWR).

Paratype: 1 ♀, same data as holotype ( ZIN).

Description. Habitus as in Fig. 4. Body size similar to that of T. holzschuhi and T. baglungensis sp. n.: length in holotype 5.7, in female paratype 5.9 mm, width 3.4 and 3.5 mm, respectively.

Colour: Body piceous, shiny on dorsum, with rather distinct bluish (holotype) or blue greenish (paratype) tinge on elytra and pronotum; labrum, pronotum along very narrow apical margin and within lateral gutters as well as elytra within lateral gutters reddish brown; epipleurae of pronotum and elytra blackish brown or (in paratype) epipleurae of elytra paler, reddish brown; palpi, antennae and legs brownish yellow, with femora very slightly infuscate.

Head: Comparatively large, with wide neck (HWmax/PWmax = 0.69 in male and female, HWmin/PWmax = 0.56 in male and 0.57 in female). Eyes convex (in male and female, HWmax/HWmin = 1.23), in lateral view wide oval. Tempora almost half as long as eye, slightly convex, somewhat abruptly sloped to neck. Genae noticeably wider than width of antennomere 1, with few short setae. Lateral margin of head between antenna and eye, like in the preceding species, slightly protruded laterally, forming an obtuse angle near eyes, distinctly bordered. Area between supraorbital furrow and upper margin of eye wide, approximately as wide as width of antennomere 2 basally. Supraorbital setigerous pore located just behind of level of posterior margin of eye, separated from supraorbital furrow approximately by width of antennomere 3 apically. Labrum slightly concave anteriorly. Clypeus slightly emarginate along anterior margin, moderately convex basally, flatly sloped to apex, with a comparatively large setigerous pore at each anterior corner. Frons and vertex convex. Mentum and submentum completely fused, submentum with one long seta on each side. Left mandible not truncate, more or less blunted at apex. Dorsal microsculpture highly obliterate on frons and vertex, more distinct laterally behind eyes, consisting of a mixture of transverse and almost isodiametric meshes. Antennae in male almost extended to basal edge of pronotum, with antennomeres 4–8 markedly longer than wide, in female antennae slightly shorter, not reaching pronotal basal edge, with shorter antennomeres.

Pronotum: Moderately transverse (PWmax/PL = 1.37–1.41), widest at the end of anterior third, moderately narrowed posteriad (PWmax/PWmin = 1.16–1.21), with one lateral seta inserted slightly before widest point. Sides rounded almost throughout, slightly sinuate just before basal angles. Apical margin very slightly emarginate, almost straight in middle portion, bordered only laterally. Apical angles slightly prominent anteriad, less obtuse than in T. baglungensis sp. n., narrowly rounded at tip, similar to those in T. holzschuhi . Basal margin nearly straight, only slightly oblique laterally, vaguely bordered at basal angles, slightly longer than apical margin and slightly shorter than base of elytra between humeral angles. Basal angles obtuse, each with a sharp, subdenticulate apex slightly protruded laterad. Pronotal disc moderately convex, strongly sloped to apical angles and moderately so to basal ones, not depressed basally. Lateral gutter very narrow, scarcely widened in apical third as in T. parvulus sp. n.. Median line distinct, superficial, ended markedly before apical and basal margins. Lateral depressions absent; basal foveae poorly delimited, small, somewhat oval and very shallow. Surface sparsely, somewhat finely and irregularly punctate along base and latero-basally behind lateral seta, also obliterate punctures present at middle portion of apical margin. Microsculpture, as in T. holzschuhi , present throughout, consisting of fine, slightly transverse meshes.

Elytra: In lateral and caudal view convex, in dorsal view oval, relatively wide (in male, EL/EW = 1.33; EL/PL = 2.27; EW/PWmax = 1.24; in females, these indices 1.32, 2.30, 1.23, respectively), widest slightly behind middle, with somewhat acute apex. Humeri prominent, widely angularly rounded at tip, with a tiny acute denticle at tip visible in caudal view. Subapical sinuation shallow. Sutural angle in both sexes acute and somewhat sharp at tip. Basal edge slightly sinuate at humerus, forming a very obtuse angle with lateral margin. Striae almost superficial, slightly impressed along entire length, crenulate basally. Intervals somewhat flat, weakly narrowed posteriad. Parascutellar setigerous pore present, large. Parascutellar striole short, as long as or shorter than distance from parascutellar pore to suture, with apex free. Interval 3 with a very small discal setigerous pore at stria 2 behind middle. Marginal umbilicate series widely interrupted at middle, with 6–8 pores in anterior group and 8–10 pores in posterior group. Microsculpture strongly obliterate, indistinct on disc, with vague transverse meshes along basal edge, sides, and at apex.

Hindwings: Reduced to tiny scales.

Ventral surface: Prosternum and metasternum finely pubescent. Metepisternum ( Fig. 32 ) markedly wider than long, strongly narrowed posteriad. Apex of last visible (VII) abdominal sternite in male widely ( Fig. 33 ), in female narrowly, somewhat angularly ( Fig. 34 ) rounded.

Legs: Protibia without longitudinal sulcus on upper surface. Profemur with three or four setae on anterioventral margin. Tarsi short, but slightly longer than in T. parvulus sp. n., metatarsus noticeably shorter than HWmin, with metatarsomeres (particularly 2–4) markedly widened posteriad, metatarsomere 1 slightly shorter than metatarsomeres 2+3. Tarsomere 5 with two pairs of ventro-lateral setae. In male, pro- and mesotarsi moderately widened.

Female genitalia: Laterotergite (hemisternite) symmetrical, with two thick setae apically. Basal stylomere with one preapical spine on external margin. Apical stylomere moderately curved, with a peg-like spine at both ventral and dorsal edges of outer margin.

Male genitalia: Median lobe of aedeagus ( Figs 35–37 ) in lateral view arcuate, C-shaped, more strongly bent ventrad just after basal bulb, with almost straight middle portion of ventral margin and with apical sixth curved ventrad; in dorsal view almost straight, narrowed to apex in distal third. Terminal lamella moderately long, evenly narrowed to apex in dorsal view, very finely serrate ventrally. Apical capitulum in lateral view ( Fig. 35 ) oblique, evenly rounded at tip, with acute dorsal flange located less distally than rounded ventral flange; in caudal view ( Fig. 36 ) semi-oval. Internal sac with longitudinal spiny folds in apical half of median lobe, without any larger spines.

Etymology. The specific name refers to the name of the type locality, the village Bubsa in the Solu Khumbu mountain range of Nepal.

Comparison. This new species is very similar to the three preceding species in habitus and in having metepisternum short, protibia not sulcate dorsally, and aedeagal median lobe arcuate, with inclined apical capitulum. As in T. (B.) holzschuhi and T. (B.) baglungensis sp. n., the mentum is completely fused with the submentum. Trichotichnus (B.) bubsaensis sp. n. is distinguished from all these species by the humerus with a small denticle visible from behind, presence of obliterate punctures at apical margin of pronotum and by male genitalia; the median lobe of the aedeagus ( Figs 35–37 ) is especially similar in shape to that of T. (B.) holzschuhi and T. (B.) baglungensis sp. n., but the terminal lamella of T. (B.) bubsaensis sp. n. is wider basally, evenly narrowed to apex in dorsal view, and the internal sac is with distinctive longitudinal spiny folds in the apical half of the median lobe and without any larger spines. Due to the semi-oval apical capitulum ( Fig. 36 ), T. (B.) bubsaensis sp. n. is similar to T. (B.) holzschuhi ( Fig. 9 ) but differs from T. baglungensis sp. n. and T. (B.) parvulus sp. n., both of which have a somewhat triangular apical capitulum in caudal view (Figs 18 and 26, 30).

Distribution ( Fig. 151 , 4). The type specimens were collected at the eastern slope of the middle Dudh Koshi Valley near Bubsa, Solu Khumbu District, eastern Central Nepal, at an altitude of 2300 m.

Figures

FIGURE 151. Distribution of the Himalayan species of Trichotichnus subgenus Bottchrus. 1, T. holzschuhi Kirschenhofer, 1992; 2, T. baglungensis sp. n.; 3, T. parvulus sp. n.; 4, T. bubsaensis sp. n.; 5, T. schawalleri sp. n.; 6, T. obliquebasalis sp. n.; 7, T. panchhaseensis sp. n.; 8, T. siklesensis sp. n.; 9, T. pusillus sp. n.; 10, T. ganeshensis sp. n.; 11, T. minutus sp. n.; 12, T. cyanescens Ito, 1998; 13, T. martensi sp. n.; 14, T. opacus Ito, 1998.

FIGURES 32 – 37. Trichotichnus (Bottchrus) bubsaensis sp. n. (32 – 33, 35 – 37, holotype; 34, paratype). left metepisternum; 33, apex of last (VII) abdominal sternite, male; 34, same, female; 35, 37, median lobe of aedeagus; 36, apical capitulum. 32 – 34, ventral view; 35, lateral view; 36, caudal view; 37, dorsal view. Scale bars = 0.25 mm (A: Figs 32 – 35; B: Fig. 36).

FIGURES 5 – 13. Trichotichnus (Bottchrus) holzschuhi Kirschenhofer, 1992 (5 – 7, paratype; 8 – 13, specimens from Sete). 5, terminal lamella of aedeagus; 6 – 8, 11, median lobe of aedeagus; 9, apical capitulum; 10, left metepisternum; 12, apex of last (VII) abdominal sternite, male; 13, same, female. 5, 7, 8, dorsal view; 6, 11, lateral view; 9, caudal view; 10, 12, 13, ventral view. Scale bars = 0.25 mm (A: Figs 5 – 8, 10 – 13; B: Fig. 9).