Chydaeus soluensis, Kataev & Schmidt, 2019

Kataev, Boris M. & Schmidt, Joachim, 2019, New data on the irvinei group of Chydaeus of the Himalaya from Nepal and southern Tibet (Coleoptera, Carabidae, Harpalini), Zootaxa 4686 (2), pp. 202-214 : 210-212

Chydaeus soluensis sp. n.

( Figs 5 , 31–37 )

Type material. Holotype: ♂, “ Nepal Solu Khumbu Lamjura Danda 35–3600 m 28–29.V.13 lg. J. Schmidt env. 27°34’N 86°30’E ” (cJS).

Paratypes: 2 ♂♂, 2 ♀♀, same data as holotype (cJS) ; 2 ♀♀, “ Nepal Solu Khumbu Taktor to Lamjura pass 3350–3450 m 28.V.13 lg. J. Schmidt env. 27°34’37”N 86°30’07”E ” (cJS) ; 1 ♂, 2 ♀♀, “ NEPAL Solu Khumbu / N Taksindo 3900 m / 24.V.2013 lg. J.Schmidt / 27°39’10”N 86°36’32”E ” (cJS) ; 1 ♂, 1 ♀, “E Nepal, Solukhumbu Distr. , Lamjura La Pass, 3500–3700 m, 27°34.8‘N 86°29.9‘E, 2.VI.2018, B. Kataev leg.” ( ZISP) ; 1 ♀, “E Nepal, Solukhumbu Distr. , Lamjura La Pass, 3500–3700 m, 27°34.8‘N, 86°29.9‘E, 2.06.2018, R.Yu. Dudko leg.” ( ISEAN) ; 8 ♂♂, 5 ♀♀, “ NEPAL Solu Khumbu / Chotanga 3300–3500 m / 20.V.2013 leg. J. Schmidt / env. 27°40‘N 86°45‘E ” (cJS, ZISP) .

Diagnosis. Very similar in appearance and male genitalia to Ch. loeffleri , but distinctly differing in having: body, on average, larger, with smaller head, pronotum with more prominent, acute apical angles, elytra fused along suture, metacoxa constantly without an additional medial setigerous pore, male pro- and mesotarsi more strongly dilated, median lobe relatively longer (MLL/L 0.26–0.27 versus 0.21–0.23), in lateral view less arcuate, in dorsal as- pect relatively narrower, its apex slightly bent dorsally, terminal lamella narrower, and inner sac with larger medial spiny patch. From other species with fused elytra and one lateral pronotal seta, Ch. soluensis sp. n. is distinguished by having left mandible truncate at tip and elytral sutural angle narrowly rounded just at tip, not sharp; also, except for Ch. ganeshensis Kataev et Schmidt, 2002 , which is much smaller (its body length 5.7–6.2 mm), by wider male mesotarsus with tarsomere 2 and 3 bearing adhesive vestiture.

Description. (five males and five females measured). Body length 7.1–8.4 mm, width 3.1–3.5 mm. Habitus as in Fig. 5 .

Coloration. Black, base of mandibles, labrum externally, palpi, antennae, usually also tarsi and base of tibiae, more rarely legs throughout and elytral epipleurae brown to blackish brown; dorsum shiny, not iridescent.

Head. Somewhat large, in male HWmax/PWmax 0.72–0.74 (m = 0.73) and HWmin/PWmax 0.65–0.67 (m = 0.66), in female these indices 0.71–0.75 (m = 0.73) and 0.65–0.69 (m = 0.67), respectively, its dorsal surface impunctate. Eyes small, weakly convex. Tempora about 0.3–0.5 times as long as eye, flat or moderately convex, sloped to neck. Clypeus very shallowly emarginate anteriorly. Fronto-clypeal suture fine, very slightly impressed along entire length. Frontal foveae somewhat small and shallow, oval. Supraorbital setigerous pore situated at level just behind hind margin of eye, removed from supraorbital furrow at a distance of about three diameters of pore. Labrum more or less shallowly emarginate anteriorly. Left mandible obliquely truncate at apex. Ligular sclerite almost parallel-sided; paraglossae narrow, scarcely longer than ligular sclerite and separated from it by deep notches. Antennae slender, not long, almost reaching elytral base, with antennomeres 4–8 about 1.3–1.5 times as long as wide. Dorsal microsculpture developed throughout, consisting of distinct isodiametric meshes.

Pronotum. Transverse, PWmax/PL 1.44–1.56 (m = 1.50), widest at beginning of second third, narrowed basad, WPmax/WPmin 1.14–1.21 (m = 1.17); sides rounded anteriorly and slightly sinuate in basal third; each with one lateral setigerous pore slightly before middle. Apical margin shallowly emarginate, bordered only laterally. Basal margin almost rectilinear, slightly rounded or oblique laterally just at basal angles, entirely distinctly bordered, slightly longer than apical margin and markedly shorter than elytral base between humeral angles. Apical angle slightly or moderately protruding, blunted or very narrowly rounded at tip; basal angle almost right, with sharp, comparatively large triangular denticle at apex slightly protruding laterally. Disc moderately convex, slightly sloped towards basal angles and markedly so towards apical angles, usually not flattened latero-basally. Lateral depressions not developed. Basal foveae small and shallow, occasionally slightly deepened, oval or elongate, not reaching pronotal posterior edge, area between them convex. Pronotal surface very finely, vaguely punctate along base, with more distinct punctures within and around basal foveae, in a few specimens also with very small, indistinct micropunctures along anterior margin and sides. Microsculpture developed throughout, consisting of distinct, more or less isodiametric meshes.

Elytra. Fused along suture, convex, oval, in male EL/EW 1.35–1.44 (m = 1.40), EL/PL 2.57–2.75 (m = 2.68) and EW/PWmax 1.25–1.31 (m = 1.28), in female these indices 1.35–1.46 (m = 1.42), EL/PL 2.63–2.83 (m = 2.74) and EW/PWmax 1.25–1.30 (m = 1.28), widest at or slightly behind middle. Humerus angulate, its apex occasionally with traces of denticle recognizable in view from behind. Subapical sinuation very shallow, indistinct, sutural angle very narrowly rounded at apex. Basal border slightly sinuate laterally, joining with lateral margin at obtuse angle. Striae very fine, superficial, crenulate, some lateral striae discontinuous in some specimens. Scutellar striole rudimentary; parascutellar setigerous pore absent. Intervals impunctate, somewhat flat, not narrowed apically. Marginal umbilicate series widely interrupted at middle, consisting of five or six basal and of six to nine apical pores. Microsculpture distinct, developed throughout, consisting of more or less isodiametric meshes in narrow area along basal border and of slightly transverse meshes on other surface.

Ventral side of thorax and abdomen. Prosternum covered with few very short setae at apical margin. Metepisternum wider than long, only slightly narrowed posteriorly. Apex of last visible (VII) sternite in both sexes with two pairs of marginal setigerous pores along apical margin and rounded at apex (in male more widely than in female).

Legs. Metacoxae without an additional medial setigerous pore (as in Fig. 6 ). Tarsi dorsally glabrous and impunctate. Tarsomere 5 with three or two pairs of latero-ventral setae. Metatarsus a little shorter than HWmin, metatarsomere 1 much longer than tarsomere 2 and slightly shorter than tarsomeres 2+3, approximately 2.5–2.7 times as long as wide at its apical part. In male, protarsi strongly enlarged, with tarsomeres 2–4 markedly wider than long ( Fig. 31 ), and mesotarsi moderately enlarged (mesotarsomere 1 unmodified), with tarsomere 2 very slightly longer than wide and with tarsomere 3 slightly wider than long ( Fig. 32 ); ventral side of protarsomeres 2–4 and of mesotarsomeres 2 and 3 covered with adhesive vestiture.

Female genitalia ( Figs 36, 37 ). Laterotergite (hemisternite) asymmetrical, markedly longer than wide, arcuately bordered along inner proximal margin, without setae; basal stylomere elongate, widened distally, also without setae; apical stylomere slightly shorter than basal stylomere, in ventral view rather narrow, nearly triangular, with wide base and strongly prominent outer basal angle, in lateral view apical stylomere moderately wide, rounded at sides, and narrowly rounded at apex.

Aedeagus. Median lobe ( Figs 33, 35 ) relatively small (MLL/L 0.26–0.27), slightly shorter than in Ch. irvnei but slightly longer than in Ch. loeffleri , in lateral view arcuate, slightly concave along ventral margin, in dorsal view moderately wide. Apical orifice in dorsal position, very wide, prolonged up to basal bulb. Terminal lamella in dorsal view ( Fig. 34 ) triangular, wider than long, with sides roundly converging to blunted apex, without apical capitulum. Internal sac with a wide spiny patch at middle of median lobe.

Etymology. The name of the species is derived from Solu, the name of the area in Solu Khumbu District where the new species occurs.

Distribution ( Fig. 38 , ‘ blue circle’). Solu Khumbu District of eastern Central Nepal, south of the Greater Himalayan main chain. Up to today known from the south stretching mountain ranges between Inkhu Khola in the east and Likhu Khola in the west.

Figures

FIGURE 38. Chydaeus, distribution: ‘red star’, Ch. irvinei (Andrewes. 1930); ‘red circle’, Ch. loeffleri loeffleri (Jedlička, 1966); ‘red square’, Ch. loeffleri tibetanus ssp. n.; ‘yellow square’, Ch. cf. loeffleri, population from Bothe Koshi Valley, see text for details; ‘blue circle’, Ch. soluensis sp. n.

FIGURES 1–5. Chydaeus, habitus (males). 1, Ch. irvinei (Andrewes. 1930), lectotype; 2, same, paralectotype from Gautsa; 3, Ch. loeffleri tibetanus ssp. n., holotype; 4, Ch. loeffleri loeffleri (Jedlička, 1966), specimen from the locality “Beding to Na”; 5, Ch. soluensis sp. n., paratype from Lamjura La. Scale bars = 1 mm.

FIGURES 31–37. Chydaeus soluensis sp. n. 31, male protarsus; 32, male mesotarsus; 33, 35, median lobe of aedeagus (33, lateral view; 35, dorsal view); 34, terminal lamella, dorsal view; 36, apical stylomere, lateral view; 37, laterotergite and stylus, ventral view. 31–35, holotype; 36, 37, paratype. Scale bar = 0.5 mm.

FIGURES 6–12. Chydaeus irvinei (Andrewes. 1930). 6, left metacoxa; 7, male protarsus; 8, male mesotarsus; 9, 10, 12, median lobe of aedeagus (9, 10, lateral view; 12, dorsal view); 11, terminal lamella, dorsal view. 6–8, 10–12, paralectotypes; 11, lectotype. Abbreviation: pmp, posteromedial pore. Scale bars: A = 1 mm (Fig. 6), B = 0.5 mm (Figs 7–12).