Sichuana curvicercata Gu, Zheng & Yue, 2023

Gu, Jun-Jie, Zheng, Chengjie, Jiang, Su-Rong & Yue, Yanli, 2023, Phylogeny of genus Sichuana Shen & Yin, 2020 (Orthoptera, Tettigoniidae, Tettigoniinae) with four new species from Sichuan, China, Deutsche Entomologische Zeitschrift 70 (2), pp. 337-355 : 337

Sichuana curvicercata Gu, Zheng & Yue sp. nov.

Material examined.

Holotype: ♂, Yonghong village , Dawei town , Xiaojin County, Ngawa Tibetan and Qiang Autonomous Prefecture, Sichuan Province, China (30°58'6"N, 102°38'16"E, alt., ca. 2800 m), coll. Cheng-Jie Zhengand Yuan Wei, VIII-2022 . Paratypes: 10♂ 1♀, same data as in holotype (Fig. 5 ) .

Diagnosis.

Differs from all other Sichuana species by male tenth abdominal tergite without projections at posterior margin (Fig. 6F ); male cercus gradually curved ventrally with apex pointing dorsally (Fig. 6E, F, H ), inner tooth thick and nearly straight, suddenly sharp and incurved at apex (Fig. 6E ); female tenth abdominal tergite with a wide trapezoidal projection at posterior margin (Fig. 6G ).

Etymology.

The specific epithet is derived from a combination of the Latin ' curvi ' meaning curved and ‘cercus’, describing the male cerci curved ventrally with the apex pointing dorsally. Chinese name: 弯尾川螽.

Measurements

(mm). Body (head to tip of abdomen): 25.36-26.77♂, 27.28♀; pronotum: 6.98-7.26♂, 7.44♀; tegmen: 11.70-12.42♂, 7.08♀; mirror of right tegmen (from fore to hind): 3.88-3.96♂; hind wing: 4.39-4.62♂, 4.79♀; protibia: 6.24-7.23♂, 7.6♀; profemur: 6.45-6.86♂, 7.28♀; mesotibia: 7.24-7.72♂, 9.32♀; mesofemur: 6.26-7.10♂, 8.16♀; metatibia: 16.33-17.19♂, 19.92♀; metafemur: 17.56-17.8♂; 20.96♀; ovipositor: 17.64.

Description.

Male. Body size medium. Frons flat, slightly oblique. Frontal fastigium and clypeofrontal sulcus black. Face light-colored. Occiput convex. Vertical fastigium broad, slightly wider than scape. Median ocellus visible. Compound eyes broadly round and bulging outwards, surrounded by black coloration that extends backward to form a black band. Filiform antennae inserted at the inner side of the compound eyes, scapus robust, much thicker than pedicel, flagellum taper toward the apex, covered with short setae (Fig. 6A-D ).

Pronotum saddle-shaped, smooth, nearly equal to profemur in length. Disc of prozona with a broadly obtuse concavity in the middle of each side, anterior margin of pronotum slightly concave and posterior margin blunt, median carina faintly indicated in prozona, absent in metazona, lateral carina distinct in metazona, faintly indicated in prozona. Lateral lobe of pronotal length greater than depth, with a light-colored stripe along the lateral margin, sometimes not obvious, humeral sinus obvious (Fig. 6A-D ). Prosternum with a pair of small cone-shaped spines (Fig. 8E ). Mesosternum with a pair of triangular lobes, nearly equal in width to height. Metasternum with a pair of rounded triangular lobes, width distinctly greater than height (Fig. 8E ). Thoracic auditory spiracle elongated and elliptical, partially covered by lateral lobe of pronotum.

Tegmen approximately equal to or slightly shorter than twice length of pronotum, with clear longitudinal and cross veins. Tegmen folded downward along M+CuA, dorsal field flat, with a transverse lacuna in the middle. Tegmen almost the same width with disc of metazona from basic until middle, and then gradually narrowing in dorsal view. Lateral field of tegmen slightly broadened (Fig. 6I ). ScA weak and short, very close to anterior margin, ending at or before middle of anterior margin. ScP strong, with 5-7 branches. R without distinct dichotomy. M+CuA separated into M and CuA after intersection of handle and M+CuA, slightly after middle of tegmen. M separated into MA and MP after origin of handle but the position of their separation is unstable (Fig. 7A-F ). Stridulatory file with about 18 teeth (Fig. 8G ). Mirror on right tegmina pentagonal, length greater than width (Fig. 7B, D, F ). Hind wing rudimentary.

Legs. Prothoracic leg: genicular lobes armed with 1-2 internal spinules and externally unarmed. Dorsal side of procoxa with a long spine. Profemur with 2-4 internal black spinules ventrally; protibia with a slit-like auditory tympanum on both sides; protibia with 0-3 external spurs dorsally, with 4-5 spurs on each side ventrally; protibia with an external apical spur dorsally and with a pair of apical spurs ventrally. Mesothoracic leg: genicular lobes armed with 0-2 spinules on each side. Mesofemur with 2-4 external black spinules and 0-2 internal black spinules ventrally; mesotibia with 2-4 external spurs and 3-4 internal spurs dorsally, with 5-6 spurs on each side ventrally; mesotibia with an internal apical spur ventrally and a pair of apical spurs dorsally. Metathoracic leg: genicular lobes unarmed; metafemur with sparse black spinules on each side ventrally; metatibia with a row of spines of different sizes on each side dorsally, with a row of sparse tiny spurs on each side ventrally, progressively denser toward apex; metatibia with a pair of apical spurs dorsally and two pairs ventrally, one of which is distinctly larger.

The apical area of the tenth abdominal tergite with a wide and pileous lacuna in the middle, covered with many tiny granular protrusions. The tenth abdominal tergite with a wide and shallow notch in the middle of the posterior margin (Fig. 6F ). Cercus conical and pileous, strongly incurved at middle; cercus curved ventrally after the middle, with the apex pointing dorsally. With a thick and nearly straight inner tooth at the base of the cercus, almost the same thickness overall, its apex abruptly thin and incurved; inner tooth slightly above the top of cercus in lateral view (Fig. 6E, F, H ). Subgenital plate length greater than width, with lateral carinae, middle part of posterior margin with a deep notch, width of notch varies; stylus slender and longer than notch (Fig. 8A-C ). Epiproct triangular. Titillator L-shaped, with 5-6 rows of dense denticles or more, gradually decreasing from base to apex on apical portion (Fig. 8F ).

Female. Generally similar to male, but body slightly larger. Tegmen shorter than pronotum, extending to the third abdominal tergum (Fig. 6B, D ). Hindwing micropterous, longer than half of pronotum. Cercus conical and pileous. The posterior margin of tenth abdominal tergite with a wide trapezoidal projection (Fig. 6G ). Subgenital plate nearly trapezoid, width nearly equal to length, middle of posterior margin with a wide notch (Fig. 8D ). Ovipositor slightly shorter than metafemur, slightly decurved distally (Fig. 6B, D ).

Remarks.

S. curvicercata sp. nov. is similar to S. planicercata sp. nov., but is distinct by: male cerci gradually curved ventrally with the apex pointing dorsally, while those of S. planicercata sp. nov. do not bend ventrally or dorsally; the inner tooth is nearly straight and almost fo same thickness overall and is suddenly sharp and incurved at apex, while that of S. planicercata sp. nov. is tapering and curving from base to apex and is far above the top of the cerci in lateral view; the posterior margin of the male tenth abdominal tergite only with a wide and shallow notch in the middle of the posterior margin, while that of S. planicercata sp. nov. has a pair of very short and inconspicuous projections (Figs 2E, F , 6E, F ); denticles on the apical portion of titillator of S. planicercata sp. nov. are fewer and sparser than those of S. curvicercata sp. nov. and are relatively larger (Figs 4F , 8F ); S. curvicercata sp. nov. with slightly fewer stridulatory teeth than S. planicercata sp. nov., and the spacing of the teeth of S. curvicercata sp. nov. is slightly wider than that of S. planicercata sp. nov. (Figs 4G , 8G ); female tenth abdominal tergite with a wide trapezoidal projection at the posterior margin, while that of S. planicercata sp. nov. have a wide rounded deep lacuna in the middle (Figs 2G , 6G ).

S. curvicercata sp. nov. differs from S. feicui He, 2020 and S. cryptospina Shen & Yin, 2020 by: the lateral field of the male tegmina is slightly broadened; in male tegmina, M+CuA separate to M and CuA after the origin of the handle; the posterior margin of the male tenth abdominal tergite is without projections; male cerci are curved ventrally with the apex pointing dorsally. Furthermore, S. curvicercata sp. nov. differs from S. feicui by its male cerci strongly incurved at the middle. These two species also differ from S. curvicercata sp. nov. in the shape of the inner teeth, the denticles on the titillator, the morphology of the female tenth abdominal tergite, the shape of the stridulatory file, and the number of stridulatory teeth.

Figures

Figure 2. A-D. Body of Sichuana planicercata sp. nov. A, B. Male holotype; C, D. Female paratype; A, C. Dorsal view; B, D. Lateral view; E. Male terminal abdomen with artificially unfurled cerci in dorsal view for showing inner tooth; F. Male terminal abdomen in dorsal view; G. Female terminal abdomen in dorsal view; H. Male terminal abdomen in lateral view; I. Male left tegmen in lateral view.

Figure 4. Sichuana planicercata sp. nov. A-C. Male subgenital plate; D. Female subgenital plate; E. Thorax in ventral view; F. Titillator; G. Stridulatory file on underside of male left tegmen.

Figure 5. Sichuana curvicercata sp. nov. A. Adult female; B-D. Adult male.

Figure 6. A-D. Body of Sichuana curvicercata sp. nov. A, B. Male holotype; C, D. Female paratype; A, C. Dorsal view; B, D. Lateral view; E. Male terminal abdomen with artificially unfurled cerci in dorsal view for showing inner tooth; F. Male terminal abdomen in dorsal view; G. Female terminal abdomen in dorsal view; H. Male terminal abdomen in lateral view; I. Male left tegmen in lateral view.

Figure 7. A-F. Tegmina of Sichuana curvicercata sp. nov. in dorsal view. A, C, E. Left tegmina; B, D, F. Right tegmina.

Figure 8. Sichuana curvicercata sp. nov. A-C. Male subgenital plate; D. Female subgenital plate; E. Thorax in ventral view; F. Titillator; G. Stridulatory file on underside of male left tegmen.