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

Lin, Chun, Huang, Shihui & Luo, Changqing, 2023, Description of five new species of the subgenus Tachycines (Gymnaeta) (Rhaphidophoridae: Aemodogryllinae: Aemodogryllini) from caves in Guizhou, China, Zootaxa 5389 (5), pp. 582-596 : 593-595

Tachycines (Gymnaeta) conicus sp. nov.

( Figs. 11 , 12 )

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

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

Female. General appearance similar to that of male ( Figs. 12A–C ), 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 ). Subgenital plate nearly rounded with fore margin projecting apically ( Fig. 12E ).

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 ; 12E ). 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.

Figures

FIGURE 4. The shape of female subgenital plates of four Tachycines (Gymnaeta) species. A. subgenital plate of T. (G.) chenhui, after Rampini et al. (2008); B. subgenital plate of T. (G.) cavernus, after Jiao et al. (2008); C. subgenital plate of T. (G.) zorzini, after Rampini et al. (2008); D. subgenital plate of T. (G.) lalinus, after Feng et al. (2019).

FIGURE 11. Tachycines (Gymnaeta) conicus sp. nov. (male). A. habitus, dorsal view; B. habitus, lateral view; C. habitus, ventral view; D. head, frontal view; E. pronotum, dorsal view; F. hind tarsus, lateral view; G. genitalia, dorsal view; H. genitalia, ventral view.

FIGURE 12. Tachycines (Gymnaeta) conicus sp. nov. (female). A. habitus, dorsal view; B. habitus, lateral view; C. habitus, ventral view; D. ovipositor, lateral view; E. subgenital plate, ventral view.