Tachycines ( Gymnaeta ) conicus, Lin & Huang & Luo, 2023

Tachycines ( Gymnaeta) conicus sp. nov.

( Figs. 11 View FIGURE 11 , 12 View FIGURE 12 )

Description. Male. Body small-sized ( Figs. 11A–C View FIGURE 11 ). Vertex of head divided into two conical tubercles, bases and apices of the tubercles separated ( Fig. 11D View FIGURE 11 ). Eyes normal, not reduced ( Fig. 11D View FIGURE 11 ).

Thorax. Anterior margin of pronotum straight, posterior margin protruding backward, ventral margin arc-shaped ( Fig. 11E View FIGURE 11 ); posterior margin of mesonotum protruding backwards; posterior margin of metanotum straight.

Legs. All legs long and slender; coxae with small medial projections. Fore femur about 2.7 times longer than the pronotum, ventrally unarmed, internal genicular lobe with 1 small spine, external genicular lobe with 1 long spine; fore tibia ventrally with 1 inner spine and 2 outer spines, apex with 1 small outer spine on dorsal surface and 1 pair of long spines on ventral surface, between the paired ventral spines with 1 small spine. Middle femur ventrally unarmed, internal and external genicular lobes with 1 long spine respectively; middle tibia ventrally with 1 inner spine and 1 outer spine, apex with 1 pair of dorsal spines and 1 pair of ventral spines, between the paired ventral spines with 1 small spine. Hind femur ventrally unarmed; hind tibia dorsally with 34–38 inner spines and 36–41 outer spines, arrange in groups, ventral and dorsal surface with a pair of small sub-apical spines respectively, apex with 1 pair of long dorsal spines and 1 pair of long ventral spines; the longest dorso-apical spine not exceeding the dorso-apical spine of hind metatarsus ( Fig. 11F View FIGURE 11 ). Hind metatarsus keeled beneath.

Abdomen. Abdominal sternites with distinct cone-like ventral projections. Epiphallus of male genitalia “H”- shaped, the upper end shallowly notched, the lower end deeply notched; median lobe of genitalia with 1 pair of apical lobules, divided by a notch; ventral lateral lobes slightly longer than dorsal ones ( Figs. 11G, H View FIGURE 11 ).

Female. General appearance similar to that of male ( Figs. 12A–C View FIGURE 12 ), but fore tibia ventrally with 1 inner spine and 1 outer spine. Ovipositor about half the length of hind femur; base of ovipositor broad, narrowing to apex, apex pointed and slightly curved upwards; nearly indistinct denticles on ventral edge of distal part of inferior valves ( Fig. 12D View FIGURE 12 ). Subgenital plate nearly rounded with fore margin projecting apically ( Fig. 12E View FIGURE 12 ).

Coloration. Body dark brown. Eyes black. Hind femora with brown stripes laterally.

Material examined. Holotype: 1♂, Anjia Cave, Zhexiang Town , Zhenfeng County, Qianxinan Buyi Miao Autonomous Prefecture , Guizhou Province, 25.VIII.2020, coll. Changqing Luo, Shihui Huang & Xueli Feng. Paratypes: 27♂, 10♀, same data as the holotype .

Measurements (mm). Body: ♂ 12.51–15.68, ♀ 14.45–14.59; pronotum: ♂ 4.91–5.06, ♀ 4.44–4.53; fore femur: ♂ 13.83–13.84, ♀ 12.03–12.21; hind femur: ♂ 21.92–22.57, ♀ 20.88–20.93; ovipositor: ♀ 9.58–9.90.

Distribution. China ( Guizhou).

Discussion. The new species is similar to T. ( G.) lalinus Feng, Huang & Luo, 2019 , but can be separated from the latter by several morphological features. Firstly, the shape of the female subgenital plate is different between these two species ( Figs. 4D View FIGURE 4 ; 12E View FIGURE 12 ). Secondly, the number of spines on the hind tibiae of this new species is lower than that in T. ( G.) lalinus (50–61 inner and 50–59 outer spines).

Etymology. The name of the new species refers to the cone-like ventral projections of abdominal sternites.