Tachycines (Gymnaeta) microtuberculatus, 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 : 589-591

Tachycines (Gymnaeta) microtuberculatus sp. nov.

( Figs. 7 , 8 )

Description. Male. Body small-sized ( Figs. 7A–C ). Vertex of head divided into two conical tubercles, bases and apices of the tubercles separated, and the tubercles obviously reduced ( Fig. 7D ). Eyes slightly reduced ( Fig. 7D ).

Thorax. Anterior margin of pronotum straight, posterior margin protruding backwards, ventral margin arc-shaped ( Fig. 7E ); 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 2.2 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 32–36 inner spines and 28–39 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. 7F ). Hind metatarsus keeled beneath.

Abdomen. Abdominal sternites with rather short ventral projections. Epiphallus of male genitalia “H”-shaped; median lobe of genitalia with 1 pair of apical lobules, divided by a notch; dorsal lateral lobes shorter than ventral lateral lobes ( Figs. 7G, H ).

Female. General appearance similar to that of male ( Figs. 8A–C ). Ovipositor longer than half the length of hind femur, base broad, narrowing to apex; apex pointed and slightly curved upwards bearing almost indistinct denticles on ventral edge of distal part of inferior valves ( Fig. 8D ). Subgenital plate nearly triangular and with a projection in the middle part of fore margin ( Fig. 8E ).

Coloration. Body yellowish-brown. Head light brown with reddish-brown tubercles. Eyes black. Hind femora with light brown stripes laterally.

Material examined. Holotype: 1♂, Bike Cave, Zhexiang Town , Zhenfeng County, Qianxinan Buyi Miao Autonomous Prefecture , Guizhou Province, 25.VIII.2020, coll. Changqing Luo, Shihui Huang & Xueli Feng. Paratypes: 16♂, 5♀, same data as the holotype . Other specimens: 47♂, 24♀, Anjia Cave , Zhexiang Town , Zhenfeng County, Qianxinan Buyi Miao Autonomous Prefecture , Guizhou Province, 25.VIII.2020, coll. Changqing Luo, Shihui Huang & Xueli Feng.

Measurements (mm). Body: ♂ 14.14–14.82, ♀ 11.88–12.76; pronotum: ♂ 4.80–5.32, ♀ 5.00–5.32; fore femur: ♂ 11.28–12.10, ♀ 10.44–11.04; hind femur: ♂ 20.10–22.22, ♀ 17.92–21.28; ovipositor: ♀ 10.44–10.82.

Distribution. China (Guizhou).

Discussion. The new species is similar to T. (G.) femoratus (Zhang & Liu, 2009) in the shape of the epiphallus of male genitalia, but can be distinguished from the latter by several morphological features. First, the body coloration of T. (G.) microtuberculatus sp. nov. is uniform yellowish-brown, but in T. (G.) femoratus , the body coloration is yellowish-brown mottled with dark brown blotches. In addition, the number of spines on the hind tibiae of this new species is lower than that in T. (G.) femoratus (both inner and outer margins with 57–65 spines).

Etymology. The name of the new species refers to the very small tubercles of head.

Figures

FIGURE 7. Tachycines (Gymnaeta) microtuberculatus 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 8. Tachycines (Gymnaeta) microtuberculatus sp. nov. (female). A. habitus, dorsal view; B. habitus, lateral view; C. habitus, ventral view; D. ovipositor, lateral view; E. subgenital plate, ventral view.