Sichuana magnicerca Gu, Zheng & Yue sp. nov.
Material examined.
Holotype: ♂, Zagunao town, Li County, Ngawa Tibetan and Qiang Autonomous Prefecture, Sichuan Province, China, (31°27'33"N, 103°10'52"E, alt., ca. 2000 m), coll. Cheng-Jie Zheng and Yuan Wei, VIII-2022 . Paratypes: 8♂ 11♀, same data as in holotype .
Diagnosis.
Differs from all other Sichuana species by notch of male tenth abdominal tergite U-shaped; large and long male cercus beyond subgenital plate (Fig. 12F, H), inner tooth small, inserted in the most basal part of cercus (Fig. 12E); notch of female tenth abdominal tergite V-shaped (Fig. 12G). The related species S. cryptospina Shen & Yin, 2020 with a pair of projections covering the inner tooth at male tenth abdominal tergite, male cercus at an obtuse angle, and broader lateral field of male tegmen, thus being similar to S. magnicerca sp. nov. (Fig. 12).
Etymology.
The specific epithet is derived from a combination of the Latin ' magnus ' meaning huge and ' cercus ', to describe its male cerci, large and longer than the subgenital plate. Chinese name: 巨钩川螽 .
Measurements
(mm). Body (head to tip of abdomen): 30.78-33.02♂, 35.1-37.34♀; pronotum: 8.16-9.04♂, 8.82-9.7♀; tegmen: 15.84-17.57♂, 8.14-8.92♀; mirror of right tegmen (from fore to hind): 4.39-4.64♂; hind wing: 8.23-8.39♂, 5.28-5.78♀; protibia: 8.12-9.14♂, 9.5-10.58♀; profemur: 7.68-8.34♂, 8.04-8.98♀; mesotibia: 9.42-10.12♂, 10.52-11.74♀; mesofemur: 8.44-9.39♂, 9.1-10.18♀; metatibia: 22.24-24.43♂, 24.36-27.76♀; metafemur: 23.02-24.88♂; 24.48-27.54♀; ovipositor: 21.48-24.39.
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 extending backward to form a band. Filiform antennae inserted at inner sides of the compound eyes, scapus robust, much thicker than pedicel, flagellum tapering toward apex, covered with short setae (Fig. 12A-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. 12A-D). Prosternum with a pair of cone-shaped spines (Fig. 14). 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. 14E). Thoracic auditory spiracle elongated and elliptical, partially covered by lateral lobe of pronotum.
Tegmen approximately equal to or slightly shorter than twice the length of pronotum, with clear longitudinal and cross veins. Tegmen folded downwards along M+CuA, the dorsal field flat, with a transverse lacuna in middle. Tegmen almost same width as disc of metazona from base to middle, and then gradually narrowing in dorsal view. Lateral field of tegmen distinctly broadened (Fig. 12I). ScA weak, very close to anterior margin, ending at or before middle of anterior margin. ScP strong, with 5-6 branches. R usually forked to RA and RP after middle of tegmen, in a few examples very distally (for example, Fig. 13D). M+CuA forked to M and CuA before origin of handle. M usually very close to RP (Fig. 13A, C, D), or fused with RP then separateing immediately (Fig. 13B). Stridulatory file with about 33 teeth (Fig. 14G). Mirror on right tegmen pentagonal, length greater than width (Fig. 13B, D). Hind wing rudimentary.
Legs. Prothoracic leg: genicular lobes armed with 1-2 internal spinules, unarmed externally. Dorsal surface of procoxa with a long spine; profemur with 3-5 internal black spinules ventrally; protibia with a slit-like auditory tympanum on both sides; protibia with 2-4 external spurs dorsally, with 5 spurs on each side ventrally; protibia with an external apical spur dorsally and a pair of apical spurs ventrally. Mesothoracic leg: genicular lobes armed with 1-2 spinules on each side; mesofemur with 2-3 external black spinules and 0-2 internal black spinules ventrally; mesotibia with 2-3 external spurs and 3-5 internal spurs dorsally, with 5 spurs on each side ventrally; mesotibia with an internal apical spur dorsally and a pair of apical spurs ventrally. 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 the apex; metatibia with a pair of apical spurs dorsally, with two pairs of apical spurs ventrally, one pair of which distinctly larger than the other.
Apical area of the tenth abdominal tergite with a slight pileous lacuna covered with many tiny granular protrusions. Posterior margin of tenth abdominal tergite with U-shaped notch in middle, sides of notch which form a pair of round blunt projections (Fig. 12E, F). Cercus large and long, extending beyond subgenital plate, conical and pileous, strongly incurved after middle, apex acute and slightly upturned. With a small, hook-like and incurved inner tooth at basal-most part of the cercus, tapering and curving from base to apex, invisible in lateral view (Fig. 12E, F, H). Subgenital plate length greater than width, with lateral carinae, middle part of posterior margin with a deep notch, width of notch varying among individuals; stylus slender and longer than notch (Fig. 14A-C). Epiproct triangular. Titillator L-shaped, with only one row of denticles, gradually getting larger from base to apex on apical portion (Fig. 14F).
Female. Similar to male, but body slightly larger. Tegmen shorter than pronotum, extending to the third abdominal tergum (Fig, 12B, D). Hindwing micropterous, longer than half of pronotum. Cercus conical and pileous. Tenth abdominal tergite depressed downward in middle, and with a V-shaped notch at middle of posterior margin, its sides forming a pair of round blunt projections (Fig. 12G). Subgenital plate nearly trapezoid, nearly equal in width to length, middle of posterior margin with a wide notch (Fig. 14D). Ovipositor slightly shorter than metafemur, slightly decurved distally (Fig. 12B, D).
Remarks.
S. magnicerca sp. nov. is similar to S. cryptospina Shen & Yin, 2020, but differs distinctly by: male cerci large and long, extending beyond subgenital plate, while those of S. cryptospina are relatively shorter and smaller, not extending beyond subgenital plate; the inner tooth is small and placed at the basal-most part of the cerci, while that of S. cryptospina is relatively larger and longer, and is placed at the sub-basal area of the cerci (Fig. 12E, F, H); the apical portion of the titillator of S. magnicerca sp. nov. has only 1 row of denticles that are aligned vertically, while that of S. cryptospina has 1-2 rows that are aligned diagonally (Fig. 14F); and the female tenth abdominal tergite is depressed downward in the middle and has a V-shaped notch, while that of S. cryptospina has a U-shaped notch (Fig. 12G).
S. magnicerca sp. nov. differs from S. feicui He, 2020, S. planicercata sp. nov., S. longilamina sp. nov. and S. curvicercata sp. nov. by its large and long male cerci, which extend beyond the subgenital plate. Furthermore, S. magnicerca sp. nov. differs from S. planicercata sp. nov. and S. curvicercata sp. nov. by: tenth abdominal tergite with a pair of round blunt projections on posterior margin; in male tegmina M+CuA branching to M and CuA before origin of handle; and lateral field of male tegmina distinctly broadened. It differs from S. feicui by its male cerci strongly incurved after middle. It differs from S. longilamina sp. nov. by male subgenital plate not extended beyond cerci, and male cerci incurved at an obtuse angle. These four species also differ from S. magnicerca sp. nov. in shape of the inner teeth, denticles on the titillators, morphology of female tenth abdominal tergite, shape of stridulatory file, and the number of stridulatory teeth.