Duolandrevus (Eulandrevus) unguiculatus Ma, Gorochov & Zhang, 2015

Zheng, Yanna & Ma, Libin, 2021, Taxonomy of the genus Duolandrevus Kirby, 1906 (Orthoptera: Gryllidae; Landrevinae) from China with a new species of the subgenus Eulandrevus Gorochov, 1988, Zootaxa 4942 (2), pp. 252-268 : 258-259

Duolandrevus (Eulandrevus) unguiculatus Ma, Gorochov & Zhang, 2015

( Fig 3 , 5 )

Duolandrevus (Eulandrevus) unguiculatus Ma , et al., 2015: 446; Liu, et al., 2015: 598; Gorochov, 2016: 52; 2017: 228; Zhang, et al., 2017: 314; Chen, et al., 2019: 553–562

Examined materials. 1 male. China: Yunnan, Mengla, Wangtianshu , Aug. 6, 2017, coll. Ren, Guodong, Hou, Wenjun and Li, Yalin ( MHBU) .

Measurements (mm). Male: BL 17.50; HL 3.64; HW 4.06; PL 2.53; PW 4.00; FWL 5.99; HFL 9.96; HTL 6.67.

Description. Male: Body sized small for this genus. Head smooth and light, almost as wide as pronotum. Vertex broad and flattened, weakly inclined. Frontal rostrum slightly convex in frontal view, slightly wider in dorsal view, and somewhat wider than antennal scape. Face transversely broad, area of antennal socket and area of lower side of eye distinctly depressed, between two areas ridged; cheek shiny and plump. Median ocellus small and transversely ovoid; lateral ocelli large and rounded. Clypeus extremely small, distal narrowed portion short. Labrum rhombus-like, with angle lateral margins and concave apically. End section of maxillary palpi longer than the third; end section of labial palpi longer than remainder sections, depressed and widened.

Pronotum widened and depressed, about 1.7 times as long as wide; anterior margin concave and arch-like, posterior margin straight. Middle of both lateral edges slightly convex. Hind wings aplasia, small (reaching posterior margin of metanotal gland) and entirely covered by forewings. Tegmina reaching middle of the fifth abdominal tergite. Oblique veins five, the latter three veins basally connected, converging at the base of diagonal vein. Chord veins three, basally connected, converging on CuA veins. Mirror conspicuous, large, about 1.8 times wider than length and as long as base field. Apical field armed with reticulated veins. Lateral field bearing four branches of Sc vein.

Both inner and outer tympanum oval-like and inner slightly larger than outer one. Hind tibiae equipped with spines on the half of proximal portion and spurs on distal part (numbered 4:4). And with five apical spurs, of them, the inner apical numbering three, and the ventral one shortest and remainder ones nearly equal to each other; as a whole, outer apical spurs longer than the inner ones. First tarsus of hind leg armed with two spines and an apical spur inside and outside respectively. Super-anal plate simple, trapezoidal. Subgenital plate acute.

Genitalia ( Fig. 5 ): Genitalia tapering distally in dorsal view. Middle lobes of epiphallus quite long, apical part bifurcate with claw-like tip. Lateral lobes of epiphallus about 2/3 length of middle lobe; its tip not bifurcate. Epiphallus ventrally possessing a lateral projection, about 1/3 length of middle lobe. Ectoparameres acute, about 2/3 length of epiphallic middle lobe.

Coloration: Body brown. Tegmina surfaces yellowish-brown. Femur light brown.

Female unknown.

Remark. Male genitalia of this species are somewhat similar to those of Duolandrevus (Eulandrevus) sonorus , but in Duolandrevus (Eulandrevus) unguiculatus , middle lobes of epiphallus are much longer than in Duolandrevus (Eulandrevus) sonorus and in all the other known species of this subgenus. Most literature record this species as not having hind wings ( Chen et al., 2019; Gorochov, 2016, 2017; Liu et al., 2015; Ma, Gorochov, & Zhang, 2015; Zhang et al., 2017a). After observing some specimens, we discovered it bears hind wings. However, these wings are very undeveloped, rather small (reaching posterior margin of metanotal gland.) and entirely covered by forewings.

Figures

FIGURE 3. Bodies of Duolandrevus (Eulandrevus) axinus and Duolandrevus (Eulandrevus) unguiculatus. A. D. (E.) axinus. B. D. (E.) unguiculatus. Scale bar: 10 mm.

FIGURE 5. Genitalia of Duolandrevus (Eulandrevus) unguiculatus. A. dorsal viewed; B. lateral viewed; C. ventral viewed.