Pterostichus ( Morphohaptoderus ) yaotiao, Wu & Chen & Shi, 2025

[8] Pterostichus ( Morphohaptoderus) yaotiao sp. nov.

Figs 1 B View Figure 1 , 1 E View Figure 1 , 4 A View Figure 4 , 5 J View Figure 5 , 19 C – D View Figure 19 , 20 View Figure 20

Type material.

Holotype: Hubei • ♂, labeled “ Hubei Province, Shennongjia, Hongping Town, Wenshui Village , 1700 m, pitfall trap, 2013. VIII. 13, Hao Huang leg. ” [in Chinese] ( IZAS) . Paratypes (a total of 3 ♂ and 9 ♀): • 1 ♂, 9 ♀, the same data as holotype ( IZAS & CBFU) ; • 2 ♂, labeled “ Hubei Province, Shennongjia, Hongping Town, Yixiantian , 1500 m, pitfall trap, 2013. VIII. 15, Hao Huang leg. ” [in Chinese] ( CBFU) .

Diagnosis.

Medium-sized species for the subgenus ( BL = 7.9–10.0 mm); elytra with linear microsculpture in both sexes; antennomeres 3 without accessory setae; pronotum nearly quadrate, lateral margins subparalleled behind middle; inner sulcus of pronotal basal fovea usually closer to median line than to lateral margin, outer sulcus short; elytral humeral tooth thick, apex weakly hooked backwards; elytral interval 3 with two setigerous pores, all adjacent to stria 2; fifth tarsomeres asetose ventrally. Apical lamella of aedeagus elongate, with faint lamellar denticle on left margin, and a large tooth on the right; ventral surface strongly ridged.

Comparisons.

This new species, P. yaotiao sp. nov., can be readily differentiated from most of the species from Hubei by the body form subparalleled; elytral interval 3 with two pores, all adjacent to striae 2; fifth tarsomere asetose ventrally.

The new species is most closely related to P. hubeicus for their similarities on the general body form, pronotal basal foveae, elytral chaetotaxy and the male genitalia, specifically median lobe of aedeagus with longitudinal ridge on ventral surface and the left margin of apical lamella with a faint lamellar denticle. But P. yaotiao sp. nov., is different from P. hubeicus in the following aspects: (1) body size much larger in P. yaotiao sp. nov. ( BL = 7.9–10.0 mm), BL = 6.8–7.8 mm in P. hubeicus ; (2) in P. yaotiao sp. nov., elytral humeral tooth thicker, apex weakly hooked backwards (Fig. 4 A View Figure 4 ); whereas in P. hubeicus , humeral tooth sharper, apex more distinctly hooked backwards (Fig. 4 D View Figure 4 ); (3) fifth tarsomeres without ventral seta in P. yaotiao sp. nov. (Fig. 1 E View Figure 1 ), but with two or three pairs of ventral setae in P. hubeicus (Fig. 1 F View Figure 1 ); (4) in P. yaotiao sp. nov., the apical lamella of aedeagus much longer and narrower, apex with a tooth near apex of the right margin (Fig. 20 C View Figure 20 ); whereas in P. hubeicus , apical lamella of aedeagus shorter and wider, without tooth on right margin (Fig. 18 C View Figure 18 ); (5) ventral surface of median lobe more strongly ridged in P. yaotiao sp. nov. (Fig. 20 B View Figure 20 ) than in P. hubeicus (Fig. 18 B View Figure 18 ).

The chaetotaxy on elytra of the new species is also similar to many species belonging to the maximus group. But P. yaotiao sp. nov. is different from them in the body form more laterally parallel; inner sulcus of pronotal basal fovea usually closer to median line than to lateral margin; male sternites without sexual modification; and apical lamella of aedeagus elongate, with very faint lamellar denticle.

Description.

BL = 7.9–10.0 mm, BW = 3.4–3.8 mm; dorsal surface dark brown to black, appendages brown; elytra with linear microsculpture in both sexes (Fig. 20 E, F View Figure 20 ).

Head slightly thickened, HW / PW = 0.55–0.59; frons without puncture; frontal sulci short and shallow; antennae reaching elytral basal fifth, antennomere 3 without accessory seta (Fig. 1 B View Figure 1 ); eyes large and hemispherical, tempora distinctly swollen behind eyes, the length of tempora a little greater than half length of eyes, eyL / tpL = 1.43–2.00; submentum with one seta on each side.

Pronotum subquadrate, wider than long, PW / PL = 1.16–1.24, widest near apical third, PBW / PW = 0.83–0.85. Anterior margin concaved at middle, distinctly narrower than posterior margin, PAW / PBW = 0.73–0.75; anterior angles broadly rounded, weakly projecting; lateral margins arched along apical third, slightly narrowed on basal two-thirds and nearly straight to posterior angles, posterior angles nearly right-angled, usually with a thick obtuse denticle but slightly projecting out. Basal foveae (Fig. 4 A View Figure 4 ) with distinct fine punctures along inner sulcus; inner sulci shallow and straight, with faintly defined boundary; outer sulci shallower and very short, less than one-third length of inner one, ending at a distance before posterior margin; a basal sulcus present between base of inner sulcus and posterior seta, usually shallowly incised with fine punctures; intersulcate area flat or weakly convex, usually with a few punctures on posterior half; area between lateral margin and outer sulcus flat; lateral channels relatively wide, at least with distinct fine punctures behind middle. Pronotal disc usually without wrinkles aside median line; median line shallow.

Elytra oblong and flat, lateral sides nearly parallel, BW / EL = 0.64–0.68. Elytral basal border nearly straight, slightly curved anteriorly near shoulder, forming a distinct obtuse angle with lateral margin, humeral tooth thick, apex weakly hooked backwards; striae without punctures; parascutellar striole joined to apical portion of stria 1, angular base of stria 1 usually absent or very short (Fig. 4 A View Figure 4 ). Parascutellar pore present; elytral interval 3 with two setigerous pores, both adjacent to stria 2, the anterior setigerous pore positioned near middle of elytra, the posterior one near apical fourth; umbilical pore series on ninth interval sparse in middle, composed of 15–18 pores (5–6, 2–3, 8–10).

Fifth tarsomeres without seta ventrally (Fig. 1 E View Figure 1 ).

Male sternite without secondary sexual modification, apex of sternite VII evenly rounded.

Median lobe of aedeagus (Fig. 20 A View Figure 20 ) stout; in lateral view, ventral margin bent near basal fifth, nearly straight at middle portion before apical fourth, slightly sinuate and then abruptly bent downwardly at apical fourth; apical orifice relatively small, weakly turned to left side, mainly opened to the dorsal surface of median lobe. Ventral surface with a very sharp and long ridge before apical orifice (Fig. 20 B View Figure 20 ): right ridge absent, only indicated on apical orifice; median ridge large and sharp, half-length of median lobe; left ridge absent. Apical lamella strongly elongate and thin; in dorsal view, apical lamella much longer than basal width ( AL / AW = 1.70–1.80), apex rounded and slightly capitate, shallowly turned to right side with a large tooth near apex of right margin (Fig. 20 C View Figure 20 ); lamellar denticle very small and faint, present near apical third of left margin. Right paramere short, apex triangular-rounded (Fig. 20 D View Figure 20 ).

Endophallus (Fig. 19 C, D View Figure 19 ) bent to ventral side across the left margin of apical lamella, major parts of endophallus located on ventral side of aedeagus; gonopore opened to basal-ventral direction of aedeagus; surface with coarse scales, densest near gonopore; gonoporal piece short and wide, slightly crenulate on its ventral margin. Two distinct lobes recognized: left pre-apical lobe (lp) large, close to ventral surface of apical lamella, decorated with fine scales, apex with a strongly chitinized piece, claw-shaped; left apical lobe (la) small and rounded, close to gonopore, decorated with coarse scales; ventral surface of endophallus pigmented between base of lp and gonopore.

Gonocoxite 2 of female ovipositor small and crescent-shaped (Fig. 5 J View Figure 5 ), obtuse apically, outer margin with two or three ensiform setae slightly smaller in compare to other species, length of the largest ensiform seta ca. 0.03 mm; dorsal margin with one ensiform seta near apical third, ridged between the ensiform seta and apex of gonocoxite 2, one nematiform seta located on the apical seventh of outer surface.

Distribution.

This species is only known from Shennongjia in Hubei and is distributed at mid-altitudes of 1500–1700 m.

Etymology.

The scientific name of the new species is derived from Qu Yuan’s work “ Shan Gui ”: 既含睇兮又宜笑 [Ji Han Di Xi You Yi Xiao], 子慕予兮善窈窕 [Zi Mu Yu Xi Shan Yao Tiao]. This couplet can be translated as: Looking affectionately and smiling charmingly, you love me for my graceful posture. Yaotiao (窈窕) is a term used to describe the graceful figure of Shangui (Mountain Spirit). As a specific name, yaotiao depicts the elegant appearance of the new species. The name is treated as a noun in apposition.