Xistra hainanensis Deng, 2022

Zhang, Rong-Jiao, Deng, Wei-An, Li, Jie-Juan & Lin, Li-Liang, 2022, Pygmy grasshoppers of the genus Xistra Bolívar, 1887 (Orthoptera: Tetrigidae: Metrodorinae), Zootaxa 5162 (2), pp. 183-197 : 187-189

1. Xistra hainanensis Deng , sp. nov.

( Figures 2–3 )

Note: Xistra hainanensis Deng was proposed in Wei-An Deng (2016) Taxonomic study of Tetrigoidea from China. Huazhong Agricultural University, PhD Dissertation, 114 p, but this PhD Dissertation has not been officially published. This dissertation does not meet the criteria of availability according to art.8.1.of the International Code of the Zoological Nomenclature; hence, Xistra hainanensis Deng, 2016 is invalidly described. Herein, this taxon is redescribed in accordance with the rules of the ICZN ( ICZN 1999: Art. 8.1).

Description. Female. Body moderate, slender, body surface smooth and interspersed with granules.

Head. Head and eyes distinctly exserted above pronotal surface ( Fig. 2a ). Vertex narrow, in dorsal view, width of vertex between eyes 0.6–0.7 times width of compound eye ( Fig. 2c ); a little narrower in front; anterior margin of fastigium narrowly rounded and not surpassing anterior margin of eye; median carina visible anteriorly; lateral margins turned backward and reaching upper margin of eye; vertex uneven with paired fossulae. In lateral view, frontal costa straight and not visible between eyes ( Fig. 2d ), protruded anteriorly and broadly rounded between antennal grooves. In frontal view, vertex with V-shaped concavity, bottom of which reaching one- third of upper inner margins of eyes ( Fig. 2e ); lateral margins reaching the level of upper margin of eyes; frontal costa bifurcated above lateral ocelli, longitudinal furrow divergent between antennae, width of longitudinal furrow of frontal ridge very narrower than antennal groove diameter ( Fig. 2e ). Antennae short, filiform, antennal grooves inserted below inferior margins of compound eyes ( Fig. 2d ), 15-segmented, the 10th and 11th segment are the longest, about 5–6 times longer than its width. Eyes globose, lateral (paired) ocelli located in slightly below the middle of compound eye height.

Thorax. Pronotal surface smooth and interspersed with dense granules ( Fig. 2b ). In dorsal view, anterior margin of pronotum truncate; lateral carinae of prozona parallel; median carina entire; obtuse humeral angles; with a pair of inconspicuous interhumeral carinae; hind pronotal process narrow and long cone-shaped, reaching two-thirds of hind tibia. In profile, median carina of pronotum straight. Lateral lobes of pronotum turning outwardly, posterior angles directed distinctly transversely and apex truncate. Posterior margins of lateral lobes of pronotum with ventral sinus and tegminal (upper) sinus. Tegmina long, ovate, apex rounded. Hind wings reaching apex of hind pronotal process.

Legs. Fore and middle femora slightly compressed and margins finely serrated, dorsal margins slightly undulated and ventral margins distinctly undulated ( Fig. 3a–b ); middle femur wider than visible part of tegmen in width. Hind femora robust and short, 3.5 times as long as wide; margins finely serrated ( Fig. 3c ); antegenicular denticles and genicular denticles acute. Outer side of hind tibia with 6–7 spines, inner side with 3–4 spines ( Fig. 3d ). First segment of posterior tarsi equal to third in length, three pulvilli of first segment of posterior tarsi equal in length, apices of all pulvilli obtuse ( Fig. 3e ).

Abdomen. Ovipositor narrow and long, length of upper valvulae 5.0 times its width, upper and lower valvulae with slender saw-like teeth. Length of subgenital plate nearly equal to its width, posterior margin of subgenital plate triangular projecting ( Fig. 3f ).

Coloration. Body dark brown. Frons dark brown. Hind wings black. Hind femur brown and lower outer side black. Hind tibia black, with a light ring in the base. Sternites of thorax and abdomen black, subgenital plate dark brown.

Male. Unknown.

Measurements (mm). Length of body: ♀ 9.1–9.4; length of pronotum: ♀ 11.5–11.7; length of hind femur: ♀ 5.6–5.8.

Type material. Holotype: ♀, China, Hainan prov., Ledong ( Jianfengling Mountain ), 18°43ʹ38ʹʹ N, 108°54ʹ38ʹʹ E, 600 m alt., 7 August 1983, collected by Ge-Qiu Liang, CLSGNU . Paratypes. 1♀, same data, CLSGNU .

Diagnosis. This new species is similar to Xistra lochengensis (Zheng, 2005) from which it differs in lateral margins of vertex reaching the level of upper margin of eyes (lateral margins of vertex slightly exerted above upper margin of eyes in X. lochengensis ); frontal costa straight between lateral ocelli (frontal costa concave between lateral ocelli in X. lochengensis ); in profile, upper margin of pronotum straight (in profile, upper margin of pronotum undulating in X. lochengensis ); middle femur wider than visible part of tegmen in width (middle femur equal to visible part of tegmen in width in X. lochengensis ). It is also similar to Xistra brachynota Li, Deng & Zheng, 2014 but differs from the latter by width of each eye 1.5 times wider than width of vertex (width of each eye 2.0 times wider than width of vertex in X. brachynota ); width of longitudinal furrow of frontal ridge very narrower than antennal groove diameter (width of longitudinal furrow of frontal ridge equal to antennal groove diameter in X. brachynota ); dorsal and ventral margins of fore and middle femora undulated (dorsal and ventral margins of fore and middle femora straight in X. brachynota ).

Etymology. The new species was named after the type locality, Hainan Island, China; adjective.

Distribution. P. R. CHINA: Hainan.

Figures

FIGURE 2A–E. Xistra hainanensis Deng, sp. nov., holotype female. A—body, lateral view; B—the same, dorsal view; C— head and anterior part of pronotum, dorsal view; D—head and anterior part of pronotum, lateral view; E—head, frontal view.

FIGURE 3A–H. Xistra hainanensis Deng, sp. nov., holotype female. A—right fore femur, lateral view; B—right mid femur, lateral view; C—right hind femur, lateral view; D—right hind tibia, lateral view; E—right posterior tarsus, lateral view; F—subgenital plate of female, ventral view.