Chydaeus shaanxiensis, Kataev, Boris M., Wrase, David W. & Schmidt, Joachim, 2014

Kataev, Boris M., Wrase, David W. & Schmidt, Joachim, 2014, New species of the genus Chydaeus from China, Nepal, Myanmar, and Thailand, with remarks on species previously described (Coleoptera: Carabidae: Harpalini), Zootaxa 3765 (1), pp. 1-28 : 7-9

Chydaeus shaanxiensis sp. n.

( Figs 2 , 16–22 )

Type material. Holotype: ♂, “ CHINA ( S Shaanxi ) Daba Shan mount. range N pass 22 km NW Zhenping, N-slope , 2850 m 32°01'N / 109°21'E (nr. mount. top/alp. meadows/plant roots) 13.VII.2001 Wrase [12]”, “ Chydaeus spec. nov. D.W. Wrase det. 02”, “COLL. WRASE BERLIN ” (cWR).

Paratypes: Paratypes: 8 ♂, 10 ♀, same data as holotype (cWR, ZIN, cJS); 1 ♂, same data, but " 2400 m, meadow under stone [11] " (cWR).

Description. Dorsal habitus: Fig. 2 .

Size. Body length 7.4–8.3 mm, width 3.5–3.9 mm; in holotype 7.4 and 3.7 mm, respectively.

Color. Body black or brownish black, shiny on dorsum, occasionally base of mandibles and epipleurae of elytra paler; palpi brownish yellow; antennae and legs brown; antennomeres partly, femora, apical portion of tibiae and tarsi usually more or less infuscate.

Microsculpture. Head in both sexes with fine isodiametric meshes behind eyes and in very narrow area under eyes. Pronotum in both sexes and elytra in male without microsculpture, in female elytra with distinct isodiametric meshes in basal half or basal third only, meshes on interval 1 often more or less strongly obliterate or absent.

Head. Comparatively large (HWmax/PWmax = 0.68–0.71 and HWmin/PWmax = 0.59–0.63), distinctly punctate, with distances between punctures greater than their diameters. Eyes small, moderately convex (HWmax/ HWmin = 0.11–0.12). Tempora oblique, sloped to neck. Clypeus slightly emarginate and vaguely bordered apically. Frontal foveae wide, moderately deepened, without clypeo-ocular prolongations. Clypeo-frontal suture shallow. Supraorbital setigerous pores situated at level of hind margin of eyes, removed on frons at a distance of about two or three diameters of pore from supraorbital furrows. Labrum deeply emarginate apically. Left mandible truncate at apex. Ligular sclerite narrow, somewhat rounded or subtruncate at apex. Antennae in male surpassing pronotal basal edge by approximately one apical antennomere, in female only reaching to pronotal basal edge; in both sexes with antennomeres 5 to 7 each about 1.6–2.0 times as long as wide.

Pronotum. Transverse (PWmax/PL = 1.50–1.61), widest at the beginning of the second third, markedly narrowed basad (PWmax/PWmin = 1.14–1.24). Sides rounded in anterior three-quarters and distinctly sinuate in posterior quarter, each with one setigerous pore slightly before the middle; lateral bead slightly widened posteriad. Apical margin shallowly emarginate, bordered only laterally. Basal margin straight or concave medially, slightly oblique laterally, distinctly bordered throughout, slightly longer than apical margin and slightly shorter than elytral base between humeral angles. Apical angles less than 90°, slightly protruded anteriad, narrowly rounded at apices. Basal angles acute, with apices slightly protruded laterad. Pronotal disc moderately convex, flattened basally, notably sloped to apical angles. Lateral depressions very narrow in apical third, slightly widened behind lateral seta, either reaching pronotal basal edge or disappearing in basal third. Basal foveae shallow and wide, area at basal angles somewhat flat. Pronotal surface punctate nearly throughout, more densely along margins and more sparsely in central portion; punctures coarsest and confluent along base.

Elytra. Convex, oval, rounded at sides, rather wide and short [EL/EW = 1.22–1.30 (1.22–1.28 in male and 1.26–1.30 in female), EL/PL = 2.34–2.51 (2.34–2.47 in male and 2.44–2.51 in female), EW/PWmax = 1.22–1.26 (in male and female)], widest at middle, not fused along suture. Humeri angulate, without denticle at apices. Subapical sinuations weak. Sutural angles not separated from each other medially, slightly less than 90°, with apices blunted in both sexes. Basal borders nearly straight, markedly arched anteriad laterally, joined each with lateral margin at sharp, nearly rectangular angle. Striae impunctate, crenulate, slightly impressed along entire length. Parascutellar strioles present, approximately as long as total width of intervals 1+2 basally; in many specimens, apices of parascutellar strioles connected with striae 1; basal setigerous pores present. Intervals nearly flat, distinctly, sparsely punctate. Umbilicate setal series continuous or rather narrowly interrupted at middle.

Hind wings reduced to very small stubs.

Ventral side. Prosternum covered with short setae; prosternal process not projected posteriad. Proepisterna (propleura) rather coarsely punctate. Metepisterna ( Fig. 22 ) short, wider than long, narrowed posteriad. Sternum VII (last visible) in both sexes with two pairs of setae along apical margin, with apex subtruncate in male and narrowly rounded in female.

Legs. Metacoxae ( Fig. 18 ) each with an additional posteromedial setigerous pore and two or three additional median setigerous pores. Tarsi setose dorsally, tarsomere 5 with three (four in some specimens) pairs of lateroventral setae. Metatarsi shorter than HWmin, with tarsomere 1 longer than tarsomere 2, but shorter than tarsomeres 2+3. In males, protarsi markedly enlarged, but narrower than protibia at apex (tarsomere 1 about as long as wide; tarsomeres 2–4 much wider than long and with adhesive vestiture ventrally); mesotarsi also markedly enlarged, but less strongly than protarsi, about as wide as mesotibia at apex (tarsomere 1 slightly longer than wide; tarsomere 2 slightly and tarsomere 3 much wider than long; and tarsomere 4 distingly smaller than tarsomeres 2 and 3, and deeply concave apically) and tarsomeres 2–3 with adhesive vestiture ventrally.

Female genitalia ( Figs 19–20 ). Apical stylomere rather narrow and only slightly curved.

Aedeagus. Median lobe ( Figs 16–17 ) robust, markedly bent ventrad just behind basal bulb, convex on ventral side. Terminal lamella slightly bent dorsad, about as long as wide, narrowly rounded at apex, with sides converging posteriad ( Fig. 21 ); apex in lateral aspect slightly swollen. Apical orifice in dorsal position, prolonged to basal bulb. Internal sac with large folded formation at middle of median lobe; any sclerotic elements absent.

Etymology. The specific name refers to the Chinese province Shaanxi, where the type series was collected.

Comparative remarks. This new species is very similar in external structural characters to C. kasaharai , but it is distinguished from the latter by smaller body size and different structure of male genitalia ( Figs 16–17, 21 ): terminal lamella of the median lobe is shorter and thicker; internal sac lacks a narrow, winded spiny patch which is present in C. kasaharai ( Figs 13–15 ).

Distribution. Chydaeus shaanxiensis sp. n. is known only from the type locality (22 km north-west of Zhenping) in the Daba Shan Mountain Range, southern Shaanxi, China. This new species seems to be a western vicariant of C. kasaharai replacing the latter in the western part of the Daba Shan.

Figures

FIGURES 1 – 6. Chydaeus, dorsal habitus (holotypes). 1, C. dissimilis sp. n.; 2, C. shaanxiensis sp. n.; 3, C. kabaki sp. n.; 4, C. weishanensis sp. n.; 5, C. belousovi sp. n.; 6, C. putaoensis sp. n. Scales = 2.0 mm.

FIGURES 13 – 22. Chydaeus. 13 – 15, C. kasaharai; 16 – 22, C. shaanxiensis sp. n. (paratypes). 13, 15 – 17, median lobe of aedeagus; 18, metacoxa; 19, laterotergite IX and stylus; 20, stylus; 21, terminal lamella of aedeagus; 22, left metepisternum. 13, 14, 17, 21, dorsal aspect; 15 – 16, 20, lateral aspect; 18 – 19, 22, ventral aspect. m. p., medial setigerous pores; p. m. p., posteromedial setigerous pores. Scales: A = 0.5 mm (Figs 14, 21), B = 1.0 mm (Figs 13, 15 – 20, 22).