Tachycines (Gymnaeta) dentatus, Li & Feng & Luo, 2021

Li, Bing, Feng, Xueli & Luo, Changqing, 2021, Four new species of the subgenus Tachycines (Gymnaeta) (Rhaphidophoridae Aemodogryllinae: Aemodogryllini) from caves in northern Guizhou, China, Zootaxa 4991 (1), pp. 150-160 : 155-157

Tachycines (Gymnaeta) dentatus sp. nov.

( Figs. 5 , 6 )

Description. Male. Body medium size ( Figs. 5A–C ). Vertex of head divided into two conical tubercles, bases of the well-developed tubercles drawn together, obtusely rounded apices separated ( Fig. 5D ). Eyes normal, not reduced ( Fig. 5D ). Anterior margin of pronotum straight, posterior margin protruding caudad, ventral margin arc-shaped; posterior margin of mesonotum protruding caudad; posterior margin of metanotum straight.

Legs long and slender. Coxae with small medial projections. Fore femur about 2.3 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 tibiae ventrally unarmed, 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 31–38 inner spines and 34–39 outer spines, arrange in groups, ventral and dorsal surface with a pair of small subapical 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. 5E ). Hind metatarsus keeled beneath.

Abdominal sternites with short ventral projections. Epiphallus of male genitalia in the shape of a “tooth”; median lobe of genitalia with 1 pair of apical lobules, divided by a visible notch; lateral sclerites developed; dorsal and ventral pairs of lateral lobes almost equal in length ( Figs. 5F, G ).

Female. General appearance similar to that of male ( Figs. 6A–C ). Ovipositor shorter than half of hind femur; base of ovipositor broad, narrowing to apex; apex pointed and slightly curved upwards; small denticles on ventral edge of distal part of inferior valves ( Fig. 6D ). Subgenital plate with 3 lobes; the median lobe nearly pentagonal, large, and the apex blunt; the paired lateral lobes nearly triangular, small, and the apex pointed ( Fig. 6E ).

Coloration. Body dark brown. Face with 2 light longitudinal stripes. Legs light brown with brown stripes.

Material examined. Holotype: 1♂, Shirong Cave, Xihe Town , Meitan County, Zunyi City , Guizhou Province, 16.XI.2019, coll. Bing Li & Xueli Feng. Paratypes: 6♂, 7♀, same data as the holotype . Other specimens: 1♂, 1♀, Shui Cave, Yongan Town , Fenggang County, Zunyi City , Guizhou Province, 6.X.2019, coll. Bing Li ; 2♀, 1♂ Yinx- ing Cave, Yongan Town , Fenggang County, Zunyi City , Guizhou Province, 6.X.2019, coll. Bing Li ; 2♂, 2♀, Youcai Cave, Xihe Town , Meitan County, Zunyi City , Guizhou Province, 14.XI.2019, coll. Bing Li & Xueli Feng ; 2♀, Xiao Cave, Yongan Town , Fenggang County, Zunyi City , Guizhou Province, 16.XI.2019, coll. Bing Li & Xueli Feng.

Measurements (mm). Body: ♂ 12.23–15.43, ♀ 13.10–14.20; pronotum: ♂ 4.58–6.32, ♀ 3.92–4.54; fore femur: ♂ 10.65–12.68, ♀ 9.88–11.61; hind femur: ♂ 18.46–24.32, ♀ 18.64–19.50; ovipositor: ♀ 8.99–9.14.

Distribution. China (Guizhou).

Discussion. This new species is similar to the above two new species, but can be distinguished from T. (G.) plumiopedella sp. nov. by its lower number of spines on the hind tibiae and the shape of the epiphallus of male genitalia, and distinguished from T. (G.) pentagona sp. nov. by the coloration of the body and shape of the epiphallus of male genitalia.

Etymology. The name of the new species refers to the shape of the epiphallus of male genitalia.

Figures

FIGURE 5. Tachycines (Gymnaeta) dentatus sp. nov. (male). A. habitus, dorsal view; B. habitus, lateral view; C. habitus, ventral view; D. vertex of head, showing conical tubercles; E. hind tarsus, lateral view; F. genitalia, dorsal view; G. genitalia, ventral view.

FIGURE 6. Tachycines (Gymnaeta) dentatus sp. nov. (female). A. habitus, dorsal view; B. habitus, lateral view; C. habitus, ventral view; D. ovipositor, lateral view; E. subgenital plate, ventral view.