Tachycines (Gymnaeta) gracilentus Zhu & Shi, 2026, sp. nov.

Tachycines (Gymnaeta) gracilentus sp. nov. urn:lsid:zoobank.org:act: 5AA44ED5-BE37-4D2A-B3F2-8DBEFB849B28 Figs 2E–F, 3, 5 Diagnosis The new species is similar to Tachycines (Gymnaeta) nulliscleritus Zhu, Chen & Shi, 2020 in the shape of the male genitalia, but it can be distinguished by the length distinctly shorter than the height, the dorso-median lobe with a lateral sclerite and the apical area of the dorso-median lobe with two pairs of lobes (Fig. 2E–F). By contrast, T. (G.) nulliscleritus is slightly shorter than high, the dorso-median lobe without a lateral sclerite and the apical area of the dorso-median lobe has a pair of lobes (Zhu et al. 2020: 91, fig. 16m). The subgenital plate of the female is trapezoid, the middle of the posterior margin slightly protruded (Fig. 5G), whereas in T. (G.) nulliscleritus, the subgenital plate is triangular. Etymology The name of the new species derives from the gracile lateral sclerite of the dorso-median lobe of the male genitalia. Material examined Holotype CHINA • ♂; Chongqing, Wuxi, Lanying; 31°24′51″ N, 109°55′47″ E; 2067 m a.s.l.; 17 Aug. 2022; Q.D. Zhu leg.; JXAUM. Paratypes CHINA • 1 ♂, 5 ♀♀; same data as for holotype; JXAUM. Other material CHINA • 1 ♂, 4 ♀♀; Chongqing, Wuxi, Lanying; 31°24′19″ N, 109°53′33″ E; 1816 m a.s.l.; 16 Aug. 2022; Q.D. Zhu leg.; JXAUM • 1 ♂; Chongqing, Wuxi, Shuangyang; 31°28′29″ N, 109°52′40″ E; 1289 m a.s.l.; 14 Aug. 2022; Q.D. Zhu leg.; JXAUM. Description BODY. Smaller than in other congeneric species. HEAD. Fastigium verticis with two tubercles, short, apices obtusely rounded, pointing forwards. Eyes ovoid, protruding forwards; median ocellus oval, located between antennal sockets, lateral ocelli circular, situated on lateral surface of basal rostral tubercles. Apical segment of maxillary palp obviously longer than subapical one, apex globular. THORAX. Pronotum broad, anterior margin of disc straight, posterior margin arcuate; lateral lobe longer than high, ventral margin arc-shaped. Mesonotum and metanotum short, posterior margin of mesonotum arcuate, posterior margin of metanotum straight. Fore coxa with one small spine; femur unarmed on ventral surface, internal genicular lobe unarmed, external genicular lobe with one long spine; tibia with one outer spine on ventral surface, apex with one outer spine on dorsal surface and a pair of spines on ventral surface with one small spine in between. Middle femur unarmed on ventral surface, internal and external genicular lobes with one long spine, respectively; tibia with zero to one outer spine on ventral surface, apex with a pair of dorsal spines and a pair of ventral spines with one small spine in between. Hind femur unarmed on ventral surface, internal genicular lobe with one small spine, external genicular lobe unarmed; tibia with 49–51 inner spines and 49–53 outer spines on dorsal surface, subapex with a pair of dorsal spines, apex with a pair of dorsal spines and two pairs of ventral spines, intero-dorsal spine clearly shorter than hind basitarsus; hind basitarsus with one dorsal spine. MALE ABDOMEN. Posterior margins of all abdominal tergites straight. Epiproct tongue-shaped, paraproct triangular in lateral view. Cercus long, conical, apex acute. Genitalia with dorsal sclerite, quadrilateral, length distinctly shorter than height, basal area slightly broad, anterior margin slightly concave, then slightly narrower, nearly parallel on both sides, posterior margin with concavity, dorso-median lobe with lateral sclerite, gracile, kidney-shaped, located on both sides of base of dorso-median lobe, apical area with two pairs of lobes, dorso-lateral lobe slightly longer than dorso-median lobe, ventro-lateral lobe cylindrical, shorter than dorso-lateral lobe, ventro-median lobe short, with concavity. Subgenital plate transverse and broad, posterior margin straight. FEMALE ABDOMEN. Ovipositor slightly curved upwards, dorsal margin smooth, apical areas of ventral margin denticulate. Subgenital plate trapezoid, the middle of posterior margin slightly protruded. COLORATION. Body uniformly light brown. Measurements (mm) Body length: ♂: 12.10–12.32, ♀: 11.60–12.74; length of pronotum: ♂: 3.42–3.48, ♀: 3.46–4.00; length of fore femur: ♂: 7.52–8.24, ♀: 7.14–8.24; length of hind femur: ♂: 12.74–14.70, ♀: 15.00–15.60; length of hind tibia: ♂: 14.22–15.70, ♀: 16.48–16.68; length of hind basitarsus: ♂: 2.22–3.06, ♀: 3.24–3.58; length of ovipositor: 7.26–8.54. Distribution China (Chongqing).