Trichotichnus (Bottchrus) martensi, 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 : 344-346

Trichotichnus (Bottchrus) martensi sp. n.

( Figs 121 , 130–134 , 151 , 13 )

Type material. Holotype: ♂, “333 Taplejung Distr. , from Yektin to Worebung Pass, 1800–2000 m, tree-rich cultural land, 21 Apr 88, MARTENS & SCHAWALLER”, “ Nepal-Expeditionen Jochen Martens ” ( SMNS).

Description (male). Habitus as in Fig. 121 . Comparatively robust and convex. Body length 6.6 mm, width 3.0 mm. Colour: Body black piceous, shiny on dorsum, with light green tinge on pronotum and elytra; labrum, very narrow margins of pronotum and apical portion of elytral margins paler, reddish brown; palpi, antennae and legs brownish yellow, femora not infuscate.

Head: Large, with wide neck (HWmax/PWmax = 0.68; HWmin/PWmax = 0.55). Eyes markedly convex (HWmax/HWmin = 1.22), somewhat wide oval in lateral view. Tempora about half as long as eye, slightly convex, somewhat abrupt to neck. Genae wide, about 1.7 as wide as width of antennomere 1, with few short setae. Lateral margin of head between antenna and eye slightly protruded laterally, forming an obtuse angle near eyes, distinctly bordered. Area between supraorbital furrow and upper margin of eye slightly narrower than width of antennomere 2 basally. Supraorbital setigerous pore located just behind level of posterior margin of eye, separated from supraorbital furrow approximately by width of antennomere 3 apically. Labrum moderately concave anteriorly. Clypeus slightly emarginate along anterior margin, slightly convex, with one setigerous pore at each apical angle. Frons and vertex convex. Mentum and submentum completely fused, submentum on each side with one long seta. Left mandible not truncate, slightly blunted at apex. Dorsal microsculpture not evident. Antennae comparatively slender, slightly surpassing basal edge of pronotum, with antennomeres 4–8 markedly longer than wide.

Pronotum: Comparatively wide (PWmax/PL = 1.42), widest slightly before middle, moderately narrowed posteriad (PWmax/PWmin = 1.17), with one lateral seta inserted slightly before widest point. Sides rounded anteriorly, almost straightly converging in posterior third. Apical margin slightly emarginate, almost straight in middle portion, bordered throughout, with very fine border at middle. Apical angles rounded, very slightly protruded anteriad. Basal margin slightly sinuate bilaterally, broadly rounded at middle and at basal angles, vaguely bordered almost throughout, noticeably longer than apical margin and only slightly shorter than base of elytra between humeral angles. Basal angles obtuse, not denticulate, slightly blunted at tip. Pronotal disc convex, markedly sloped to apical angles and moderately so to basal ones, not depressed basally; small area near basal angles slightly flattened. Lateral gutter very narrow basally, very slightly widened in apical half. Median line very fine, superficial, crenulate, ended markedly before apical and basal margins. Basal foveae absent. Surface very finely and densely punctate along base and in latero-basal area, also with very fine scattered punctures at apical margin medially. Dorsal microsculpture present throughout, consisting of fine transverse meshes.

Elytra: In lateral and caudal view convex, in dorsal view oval, moderately wide (EL/EW = 1.35; EL/PL = 2.38; EW/PWmax = 1.24), widest at middle, with somewhat acute apex. Humeri prominent, angularly rounded at tip, without denticle. Subapical sinuation weak but distinct. Sutural angle acutangular, not blunted at tip. Basal edge slightly sinuate laterally, forming a very obtuse angle with lateral margin. Striae smooth, striae 1–5 somewhat superficial, striae 6–8 slightly impressed along entire length. Parascutellar setigerous pore present, large. Parascutellar striole on right elytron as long as distance from parascutellar pore to suture, with apex free, on left elytron slightly longer, with apex connected with stria 1. Intervals nearly flat, external ones subconvex apically. Interval 3 with one discal setigerous pore at stria 2 behind middle. Marginal umbilicate series widely interrupted at middle, with 8–9 pores in anterior group and 9–10 pores in posterior group. Microsculpture strongly obliterate, consisting of poorly visible thin lines.

Hindwings: Reduced to tiny scales.

Ventral surface: Prosternum and metasternum finely pubescent. Metepisternum ( Fig. 130 ) slightly wider than long, markedly narrowed posteriad. Apex of last visible (VII) abdominal sternite (in male) rounded ( Fig. 131 ).

Legs: Protibia not sulcate on upper surface. Profemur with four and six setae on anterio-ventral margin. Tarsi short, metatarsus noticeably shorter than HWmin, with metatarsomeres (particularly 2–4) moderately widened posteriad, metatarsomere 1 approximately as long as metatarsomeres 2+3. Tarsomere 5 with two pairs of ventrolateral setae. Pro- and mesotarsi (of male) comparatively weakly widened.

Male genitalia: Median lobe of aedeagus ( Figs 132–134 ) relatively large, in lateral view strongly bent just behind basal bulb, with ventral margin very widely sinuate in medial portion and slightly convex in apical third; in dorsal view median lobe in distal half evenly narrowed to apex and slightly curved to the right side. Terminal lamella in dorsal view short and narrow, with sides converging apicad. Apical capitulum in lateral view ( Fig. 132 ) large, slightly oblique, approximately equally prominent ventrally and dorsally, in caudal view ( Fig. 133 ) narrow, elongate oval, with acute apex. Internal sac with a spiny patch at middle.

Etymology. This new species is named in honour of Prof. Dr. Jochen Martens (Mainz), renowned biogeographer of High Asia and participant of the 1988 expedition to the Eastern Nepal Himalaya during which the new species was found.

Comparison. This new species is most similar to T. (B.) cyanescens and particularly to T. (B.) loebli and T. (B.) sikkimensis sp. n. in comparatively large size and habitus, also in having short metepisternum, not infuscate femora, pronotal lateral gutter slightly widened anteriad, pronotal and elytral discs with fine microsculpture, and humerus without denticle at tip. In addition, the pronotal basal angles are slightly blunted at apex as in T. (B.) loebli . Trichotichnus (B.) martensi sp. n. markedly differs from all these species in having mentum and submentum completely fused, protibia not sulcate on dorsal side, and median lobe of the aedeagus in lateral view straighter, with almost straight ventral margin and with a very large slightly oblique apical capitulum ( Fig. 132 ).

Distribution ( Fig. 151 , 13 ). Up to today only found on the western slope of the Singalila mountain range, Taplejung District, East Nepal, at altitudes of 1800–2000 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 120 – 123. Himalayan species of Trichotichnus subgenus Bottchrus, photographs of habitus. 120, T. sikkimensis sp. n., holotype; 121, T. martensi sp. n., holotype; 122, T. hingstoni Andrewes, 1930, male from Kechu Pheri Lake; 123, T. birmanicus Bates, 1892, male from the Kali Gandaki, Tatopani.

FIGURES 130 – 134. Trichotichnus (Bottchrus) martensi sp. n. (holotype). 130, left metepisternum; 131, apex of last (VII) abdominal sternite, male; 132, 134, median lobe of aedeagus; 133, apical capitulum. 130 – 131, ventral view; 132, lateral view; 133, caudal view; 134, dorsal view. Scale bars = 0.25 mm (A: Figs 130 – 132, 134; B: Fig. 133).

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).