Caconemobius dibrachiatus Ma and Zhang

Ma, Libin, Zhang, Tao & Qi, Tao, 2015, First record of cricket genus Caconemobius (Grylloidea: Nemobiinae) from China with description of a new species, Zootaxa 3914 (5), pp. 585-590 : 587-588

Caconemobius dibrachiatus Ma and Zhang sp. nov.

( Figs. 3 A–I)

Type materials. Holotype. Male, China: Guangdong, Shenzhen, Yangmeikeng, Sept. 29 2014, coll. Zhang Tao ( SNNU). Paratypes. China: 4 males and 4 females, data same to holotype.

Measurements. BL 7.60±0.62, HW 2.39±0.16, PL 1.73±0.12, PW 2.55±0.16, MTL 3.33±0.42, HFL 5.85±0.64, HTL 4.76±0.54, CL 4.48±0.67, OL 5.65±0.27

Etymology. The specific epithet “ dibrachiatus ” refers to the ectoparamere armed with bifurcate apex.

Diagnosis. Body color light, ornamented with dark and light patterns. Lateral ocelli absent. Inner sub-apical spurs on hind tibiae always single and varied. Weakly ossified portion between epiphallic lateral well-ossified portions trapezoid-like. Proximal margin of epiphallus bisinuate with small rounded notch. Ectoparamere equipped with apex bifurcate and fine.

Description. Male. Body large for a Nemobiinae species. Head light coloured and smooth. Along with rostrum lateral margin armed with three setae respectively. Palpi and antennae with less short hair. Head slightly narrower than pronotum. Occiput convex. Vertex inclined and somewhat flattened. Rostrum convex, narrower than antennal scape. Antennal scape transverse wider, shield-like. Eyes nearly triangle-like, with arc-shaped top margin and acute bottom. Face (between rostrum and rostrum suture) slightly convex and broad. Rostrum suture nearly straight. Basal portion of labrum ladder-shaped, gradually constricting toward tip, and narrowed, not covering maxilla. Labrum oval, shield-shaped, with median portions broad, somewhat square and slightly convex, with rounded lateral and bottom margins. Maxillary palpi rather long and horn-shaped with swollen apex, end section conspicuously longer than the third and almost equal to the total length of remaining ones ( Fig. 3 H). Labrum palpi short, end section obviously longer than remaining ones. Ocelli undeveloped, lateral ocelli absent, median ocellus very small, located at the top of rostrum, transverse oval, and just a pit.

Pronotum laterally broad ( Figs. 3 A, B), obviously wider than head; anterior margin slightly sinuate, posterior margin concave as broad arc, without lateral edge, portions between disc and lateral lobe rounded, bottom of lateral lobes could be viewed from dorsum. Blade-shaped pattern shaped as inward inclined line. Median groove inconspicuous and short. Setae located at anterior and posterior margin but absent at median portion. Lateral lobes vertically short, with almost straight bottom margin. Of lateral lobes, anterior and posterior corner rounded, but hind portion wider than the anterior. Wings absent.

Legs rather long, hind femur almost equal to length of body ( Figs. 3 A, B). Legs slightly pubescent. Fore tibiae without acoustical apparatus. Fore and median femur armed with several short spines, distributed irregularly. Second tarsus rather short, the first and third long and almost equal to each other. Fore and median tibiae armed with two apical spurs. Hind tibiae armed with one inner (always at least one, sometimes two and rarely three) and three outer sub-apical spurs. Inner apical spurs longer than the outer. The top and median inner apical spurs somewhat pinniform, the top longer than the median, and the bottom rather short. Outer apical spurs rather short, the median longest and the top shortest. Under tarsus armed with several regular spurs. Claw simple, equipped with a soft, thick and curved hair respectively.

Abdomen slightly pubescent. supra-anal plate simple. Cercus swollen at base and thin along most portions, armed with thin, soft and long hairs, and also possessing sheet-like hairs ( Figs. 3 G, I). Subgenital plate simple, cuculiform, with acute and rounded tip margin.

Genitalia. Epiphallus cuculiform ( Fig. 3 D). Epiphallus possessing weakly sclerotised portion which varies after drying. Sclerotised portions of epiphallus armed with trapezoidal distal margin and bisinuate proximal margin (median notch small and rounded) ( Fig. 3 C). Ectoparamere armed with bifurcated apical apex and thick proximal portion with notch at tip (lateral portions acute respectively) ( Fig. 3 E). Ectoparamere equipped with weakly ossified portions inside ( Fig. 3 E).

Coloration. Body colored grey and ornamented with brown patterns (sometimes more dark and ornamented with light color, but kept in same patterns). Ovipositor colored reddish brown with dark brown lateral median line ( Fig. 3 G).

Female. Similar to male ( Fig. 3 B). Ovipositor straight and long, somewhat longer than abdomen. Apex acute, with large top portion and small and sheet-like bottom portion ( Fig. 3 G).

Remarks. Genitalia of this genus equipped with several portions weakly ossified which would vary when fresh and dried. The features of ossified portions of genitalia are considerable. Epiphallic ossified portion of the base and lateral, and outside of ectoparamere are identifying features. In the new species, epiphallic proximal margin bisinuate with almost half rounded notch ( Fig. 3 C); distal margin of its ossified portion trapezoid-like and ectoparamere armed with bifurcate tip of the proximal and the distal ( Figs. 3 C, E). This species is similar to those distributed in Japan and Korea ( Ichikawa et al., 2000; Kim & Kim, 2010; Oshiro, 1986, 1990a, 1990b). But genitalia characters and body size mentioned above easily distinguish the new species from them.

Figures

FIGURE 3. Caconemobius dibrachiatus sp. nov. (A – I). Body (A, B), A male, B female; Genitalia (C – F), C dorsal viewed, D lateral viewed, E ventral viewed, F caudal viewed; Ovipositor (G); Maxillary palpi (H); Cercus (I).