Tachycines (Gymnaeta) pentagona, 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 : 151-153

Tachycines (Gymnaeta) pentagona sp. nov.

( Figs. 1 , 2 )

Description. Male. Body medium size ( Figs. 1A–C ). Vertex of head divided into two conical tubercles, bases of the well-developed tubercles not drawn together, obtusely rounded apices separated ( Fig. 1D ). Eyes normal, not reduced ( Fig. 1D ). Anterior margin of pronotum straight, posterior margin protruding caudad, ventral margin arcshaped; posterior margin of mesonotum protruding caudad; posterior margin of metanotum protruding caudad.

Legs long and slender. Coxae with small medial projections. Fore femur about 2.5 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 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 31–38 inner spines and 37–41 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. 1E ). Hind metatarsus keeled beneath.

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

Female. General appearance similar to that of male ( Figs. 2A–C ). Ovipositor shorter than the half of hind femur; base of ovipositor broad, narrowing to apex; apex pointed and slightly curved upwards; almost indistinct denticles on ventral edge of distal part of inferior valves ( Fig. 2D ). Subgenital plate with 3 nearly pentagonal lobes, median lobe rather large and paired lateral lobes small ( Fig. 2E ).

Coloration. Body yellowish brown, mottled with dark brown blotches. The two conical tubercles of vertex dark brown. Face with 2 light brown longitudinal stripes under eyes. Legs with light brown annular stripes.

Material examined. Holotype: 1♂, Qinglong Cave, Yongan Town , Fenggang County, Zunyi City , Guizhou Province, 16.XI.2019, coll. Bing Li & Xueli Feng. Paratypes: 7♀, same data as the holotype . Other specimens: 2♂, 4♀, Shui Cave, Yongan Town , Fenggang County, Zunyi City , Guizhou Province, 6.X.2019, coll. Bing Li ; 1♀, Shang Cave, Xihe Town , Meitan County, Zunyi City , Guizhou Province, 15.XI.2019, coll. Bing Li & Xueli Feng ; 1♀, Shi- rong Cave, Xihe Town , Meitan County, Zunyi City , Guizhou Province, 16.XI.2019, coll. Bing Li & Xueli Feng.

Measurements (mm). Body: ♂ 12.22–12.58, ♀ 10.78–12.74; pronotum: ♂ 4.62–4.63, ♀ 3.54–4.08; fore femur: ♂ 11.44–12.75, ♀ 9.48–9.76; hind femur: ♂ 22.57–24.27, ♀ 18.43–19.67; ovipositor: ♀ 8.90–9.82.

Distribution. China (Guizhou).

Discussion. This new species is similar to T. (G.) wuyishanicus (Zhang & Liu, 2009) in the shape of the epiphallus of male genitalia and the shape of the median lobe of female subgenital plate, but can be distinguished from the latter by several morphological characteristics. First, the lateral sclerites of male genitalia of T. (G.) pentagona sp. nov. are more developed than those in T. (G.) wuyishanicus (Zhang & Liu, 2009) . Second, the shape of the lateral lobes of female subgenital plate is different between these two species. Third, the number of spines on the hind tibiae of this new species is lower than that in T. (G.) wuyishanicus (Zhang & Liu, 2009) .

Etymology. The name of the new species refers to the shape of the 3 lobes of the subgenital plate.

Figures

FIGURE 1. Tachycines (Gymnaeta) pentagona 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, dorsal view; F. genitalia, dorsal view; G. genitalia, ventral view.

FIGURE 2. Tachycines (Gymnaeta) pentagona sp. nov. (female). A. habitus, dorsal view; B. habitus, lateral view; C. habitus, ventral view; D. ovipositor, lateral view; E. subgenital plate, ventral view.