Drabescus shillongensis Rao

Viraktamath, C. A., Webb, M. D. & Yeshwanth, H. M., 2022, Review of the leafhopper genus Drabescus Stål (Hemiptera: Cicadellidae: Deltocephalinae) in the Indian subcontinent with description of one new species, Zootaxa 5128 (2), pp. 225-247 : 239-246

Drabescus shillongensis Rao

Figs 2 EFL, 3I, 5G, 12A–H.

Drabescus shillongensis Rao 1989: 65 , figs 28–34; Zhang & Webb 1996: 25, figs 392–396, 532.

Brown with white markings. Head with fore margin yellowish white extending laterally on to eyes, margined dorsally and ventrally with dark brown border. Eyes greyish brown. Face across eyes, entire frontoclypeus and clypellus black, lateral area adjacent to inner margins of eye, lateral margins of frontal suture, inner areas of lora reddish brown; genae and lora bright lemon yellow. Antennae more or less ochraceous. Pronotum with anterior border white with anterior narrow dark brown margin, sublateral area white with lateral area dark brown, lateral carinae white; disc brown spotted with white. Exposed mesonotum brown, lateral borders and apex whitish, lateral most margin dark brown. Forewing hyaline tinged with brown, apex of clavus spotted with brown, appendix and apical cells darker; veins and wing margins dark brown spotted with white. Legs ochraceous with bases of setae on hind tibiae and some segments of tarsi darker.

Crown angularly produced medially, longer medially than next to eyes, slightly more than 4× longer than median length, transition to face angular with fore margin rimmed. Pronotum about 2× as wide as long. Forewing with claval veins not approximate at midlength. Fore tibiae not dilated.

Male genitalia. Pygofer gradually narrowed posteriorly with ventral spine-like process arising from ventral margin at apex exceeding pygofer apex, dorsoposterior angle conically rounded, dorsal margin concave, about 1.5× as long as height at base in lateral view. Valve with posterior margin convex, about 2.8× as long as wide at base. Subgenital plate broad in basal 0.2 and then narrowed distally, 3× as long as wide at base. Style with well-developed subapical lobe, apophysis straight, finger-like, transversely striate. Connective with stem rectangular, about as long as arms. Aedeagus with well-developed dorsal apodeme, about 0.6× as long as shaft; aedeagal shaft directed dorsally, tubular, slightly narrowed distally, with pair of thin curved basal processes about half as long as shaft strongly convergent in distal half, gonopore subapical on ventral surface.

Female pregenital segment. Sternite VII transverse and quadrangular, with posterior margin medially strongly produced into distally narrowed well-sclerotized lobe, sternite about 3× as wide as long medially excluding median projection and about 1.25× as wide as median length including median projection.

Measurements. Male 7.3 mm long, 2.7 mm wide across eyes and 2.4 mm wide across posterolateral angles of pronotum.

Material examined. INDIA: Meghalaya: HOLOTYPE ♂, Shillong, 6.xi.1981, C. A. Viraktamath ( UASB); 1♀, same data as holotype, (head mutilated) ( UASB).

Remarks. This species was described from a single specimen (holotype) with the following data: “Shillong, 6.xi.1981, C.A. Viraktamath, Coll.”. The type was examined and its aedeagus figured by Zhang & Webb (1996, figs 393, 396). Among the species of Drabescus known from the Indian subcontinent, the male can easily be distinguished by its elongate slender tubular aedeagal shaft with basal processes about half as long as the shaft and strongly distally convergent. The female can be recognised by the strongly medially produced narrow lobe about as long as or longer than the length of sternite VII excluding the median lobe. A female specimen has the head damaged and hence was not measured.

Figures

FIGURES 2 A–L. Species of Drabescus from Indian subcontinent. Habitus, dorsal and lateral views (A–F) and female sternite VII (G–L). A–B, D. nervosopunctatus Signoret; C–D, D. nigrofacialis (Distant); E–F, D. shillongensis Rao; G, D. angulatus Signoret; H, D. kempi Pruthi; I, D. limbaticeps Signoret; J, D. nervosopunctatus Signoret; K, D. nigrofacialis (Distant); L, D. shillongensis Rao.